How To Use A Plate Bevelling Machine

    Here is a professional guide about how to use a manual feed plate beveller aka plate bevelling machine and it’s setting up, tool change, cleaning, and maintenance.

    This is a step by step complete guide on how to use plate beveling machines. In brief, this article covers the following points,

            Components of the SKF 25 plate beveling machine

            Safety measure before setting up the plate beveller

            Checking the workpiece

            Setting the milling head of the plate beveller

            Setting the chamfer width plate beveller

            Mounting the rollers of the plate beveller

            Milling with the plate beveller

            Using the plate beveller

            Tool change of the bevelling machine

            Cleaning of the bevelling machine
        
            Maintainance of the bevelling machine

            Safety measure before setting up the plate beveller

             The beveling machine may only be operated in a horizontal position. Secure the workpiece.

             Checking the properties of the workpiece. 

             The surface of the workpiece must meet the following require- ments. The surface must be smooth and may not have any burn points, slag, welding joints or similar.  Before beginning with milling, remove surface unevenness. 

                 Setting the milling head
                                
                 Place the machine onto the upper side (power connecting cable ).  Release the locking mechanism (2) on both sides of the machine. Set the desired milling angle. The milling angle can be viewed on the scale (1). Tighten the locking mechanism (2) on both sides of the machine.

            Setting the chamfer width

            Place the machine onto the upper side (power connecting cable ). Release the locking mechanism (1). Set the desired chamfer angle by turning the adjusting screw (3). The chamfer width can be viewed on the scale (2). Tighten the locking mechanism (1).

    Mounting the guide roller for milling plates

      Mount the plate (3) according to the illustration. Fix the guide rollers (2) in the borehole (1) with the washer and nut.

        What is Pipe Beveling? How to Bevel a Pipe?
    
        Pipe beveling is an angle forming between the edge of the end of a pipe or tube. When the pipe end is formed with a certain degree of an angle, it is called a bevel end or beveled end. Pipe beveling is an essential step in the welding preparation process of pipe joining. The quality of the beveled pipe directly affects the quality of the welding, so that proper pipe preparation ensures the best possible weld joint. Other than welding, beveling can also be used for deburring the cut pipe ends for aesthetic and safety reasons.

        There are several pipe end preparation methods for welding. In this article, the types and pros, and cons of pipe beveling machine will be discussed.

            What is correct, beveling, or bevelling?

            Both beveling and bevelling are correct. 'Pipe bevelling' is the English UK spelling and 'pipe beveling' is the English US. Also, the wording pipe chamfering, pipe end working, pipe end preparation, and pipe prepping are other common terms for this application method.

            Beveling vs. Chamfering: What is the difference?
        
            Pipe chamfering is technically a type of pipe beveling. Both terms refer to an edge forming between two faces of a pipe or tube. However, the main difference between pipe chamfering and pipe beveling is that a chamfer is an edge that connects two faces at a 45 degrees angle, whereas the bevel's slope can be any angle except 45 or 90 degrees.

            How to Bevel a Pipe?

            There are various ways to bevel a pipe. Using a portable or stationary beveling machines, doing it by a hand grinder, or by a plasma or torch cutter.

            The hand grinding method of pipe beveling is the cheapest and the most dangerous method compared to using a pipe beveling machine. It is time-consuming, and a skilled operator is required to perform a bevel on a pipe by a hand grinder. Moreover, it is nearly impossible to keep the bevel quality the same for each pipe operation while creating a lot of mess.

            Using a torch or plasma cutter is another type of pipe end preparation machine. It provides faster results compared to a hand grinder, however; it also has some drawbacks. The flat land at the end of the pipe needs to prepared by hand, which is not a safe process. Yet again, the command produced will be inconsistent.
        
        
            Also, this pipe beveling method cannot be used on all materials, which would affect your flexibility in production.
        
            A portable beveling machine comes in different configurations and is notably safer than the previous two methods. The biggest advantage of these portable machines is that they are portable so that it's time-efficient since the user can take the machine to the pipe. They are convenient to use for maintenance work, or on a construction site. However, they are inadequate to meet high production requirements.

            Stationary beveling machines provide the most options and flexibility for pipe beveling. Almost all kinds of pipe bevel shapescan be created with different combinations of tools. They are designed to meet high production requirements in a safe working environment. Also, stationary pipe beveling machines are easy to integrate with automated production lines, so that the operator does not even have to be on the machine all the time. There are various benefits of stationary beveling machines such as; standard carbide cutting inserts are inexpensive to replace when needed, easy to set up and requires low maintenance, ensures the lowest cost and fastest cycle time per bevel, provides safe working environment without creating a mess, offers a broad range of machining options and can machine several pipe or tube materials, and does not require a skilled operator. Last but not least, stationary pipe beveling machines ensure constant pipe bevel quality that directly affects the quality of pipe welding.

            The pipe cutting machine developed in this study is a portable device used to cut a steel pipe. The machine, which is attached to the steel pipe by magnetic force, is moving around the pip e using four wheels. It also works for straight cutting of a steel plate. For the higher precision and labor time reduction, the automation of a pipe-cutting process is needed. However, it is not easily achieved because of vibrations and the loss of track. It is also found that the problems of the automation arise from the coupling of the functional requirements for the pipe-cutting machine. So, it is very difficult io solve the problems by a conventional design method. 

            Manufacturers of all types of industrial products go to great lengths when promoting the features and benefits of their products on their websites. But many fall short of offering any real guidance on how to choose the right machine for each individual customer’s needs. So, to help out, we’re pleased to offer guidance to people wanting to know more about flange facing products. Included are answers to some of the commonest questions our technical sales team encounter.

            SECTION 1: BEGINNER BASICS

            If you’re new to flange facing. Here are answers to some of the more fundamental questions;

            Why is there a need for flange facing machines?

            Although flanges are mass-produced with machined surfaces, damage to the flange surface during transit and installation can occur. This results in scratches and dents to the sealing surface. Damage like this puts the integrity of the joint at risk – with potentially disastrous consequences. Even after pipelines have become operational, a joint’s integrity can be compromised by corrosion inside the joint. When this happens, the flange often needs to be replaced and can be removed using a split frame/clamshell cutter.

            What are the main industries using flange facing machines?

            These include petrochemical and pharmaceutical production plants, oil wells, pipelines and power generation plants.

            How do flange facers work?

            They work in a similar way to a gramophone player, with the cutting tool traveling in a spiral path across the face of the flange. This surface finish is commonly specified for flanges in the oil and gas industries, with the gasket material being compressed to fill the spiral groove. A flange with a spiral grooved finish is less liable to leakage, as any gas or liquid is forced to travel in the long spiral path rather than across the flange face.

            How are they powered?

            Pneumatic is the standard method, but hydraulic versions can be provided as an option on many machines in the range.

            How do I know if the flange surface needs machining?

            We recommend you read our previous blog article which includes a section covering what ASME states as acceptable flange damage.

            SECTION 2: APPLICATIONS FOR A FLANGE FACING MACHINE

            Raised Face Flanges, Heat Exchanger Flanges, Techlok Flanges, Recessed Gaskets & Spigots, Weld Preps, Hub Profiles, RTJ Flanges, Lens Ring Joints, SPO Compact Flanges, Swivel Ring Flanges.

            Note: to carry out some of the above applications you will need additional options and accessories.

            What options and accessories are available?

            Optional components for widening the usage of the flange facing machine include:
          
            Compact flange machining kit to convert your existing flange facer. Alternatively you can specify a dedicated compact flange facing machine at the time of order.

                    Journal/end shaft turning kit

                    Heat exchanger mounting kit

                    Heat exchanger back facing kit

                    Lens ring machining kit

                    Orbital milling kit, replacing the single point tool post with a milling head.

                    Hydraulic conversion kit – to convert a pneumatic machine to hydraulic drive.

            Can a flange facing machine work in a subsea environment?

            Yes, however it will need to be a hydraulically powered.

            SECTION 3: CHOOSING A FLANGE FACING MACHINE

            What size machine do I need?

            There are many different sized flange facing machines available, for example smaller machines can be used on flanges from 2” up to 12” and the larger machines covers sizes from 45” up to 120”. Additionally, the MM1080ie is a unique design which can be mounted internally or externally and used to machine flanges from 0” all the way up to 157” diameter.

             Pipe Cutting and Beveling Machine

            This user pipe cutting and beveling machine is used for cutting and blanking of offshore wind power jackets. The jacket has been in the ocean for a long time, and the environmental conditions such as wind, waves, currents and ice are very harsh, so the manufacturing quality requirements are very strict. As the scale of wind power jackets tends to be larger, the corresponding pipe diameters and wall thicknesses of the pipes, ties, and columns have also increased. During the processing process, the pipe end intersecting lines have various mouth shapes, and the cutting difficulty and accuracy are also increasing. High, ordinary manual cutting methods can no longer meet the requirements. Aiming at the shortcomings of manual processing methods such as low production efficiency, high labor intensity, and poor product quality, the Kasirui technical team has developed a large pipe diameter intersecting wire cutting machine equipment to solve the problem of difficult cutting of large pipe diameter pipes!

            What is pipe beveling?

                Pipe beveling is the process where an angle is formed between the edge of the end of a pipe or tube and a plane perpendicular to the surface. A standard pipe bevel angle for welding is 37.5 degrees. Other angles and special forms such as J-Bevels can also be produced on the ends of pipe or tube using automatic pipe bevelling machines.

            Why bevel a pipe?

                Bevelling of pipe or tubing is most commonly used to prepare the ends for welding. It can also be used for deburring the cut ends for safety and aesthetic reasons.

            Why we need to automized pipe bevelling?

                ? Save time – stationary pipe cutting and beveling machine is many times faster than other methods such as hand grinding, flame cutting, hand held bevelers, or loading into a lathe.
? No more dirty operations such as hand grinding or torching.
? Consistent accurate pipe bevels each time, will face the end of the pipe square and bevel or deburr ID as needed.
? Cycle time normally in the 5 to 20 second range depending on size
? Eliminates ergonomic issues from operator handling hand tools
? Safer than hand grinding or torching, all chips are contained within the machine.
? Low operating cost, uses mostly industry standard carbide tooling
? Easily bevels stainless and materials not suitable for torching.
? Special forms such as J-bevels are easily produced.
? Can be operated by a non-skilled operator once setup.

The Benefits and Drawbacks of an Air Suspension System

    he United States developed the air suspension system during World War II specifically for heavy aircraft. The original purpose of air suspension was to save weight with a compact construction. Back then, air suspension systems were also used in other aircraft and some heavy trucks to achieve a self-leveling suspension. This would ultimately result in a vehicle with an axle height independent of the weight of a vehicle's cargo.

    Ultimately, the air suspension system offers several benefits and drawbacks for drivers who rely on larger trucks and vehicles to carry heavy loads.

    What Is an Air Suspension System?

    An air suspension system is a style of vehicle suspension that's powered by an electric pump or compressor that pumps air into flexible bellows that are typically made out of a textile-reinforced type of rubber. Additionally, Pro Car Mechanics describes air suspension as a replacement to the leaf suspension or coil spring system with airbags composed of polyurethane and rubber. A compressor inflates the bags to a certain pressure in order to behave like springs. Air suspension also differs from hydropneumatic suspension because it uses pressurized air instead of pressurized liquid.

    What's the Purpose of an Air Suspension System?

    In most cases, air suspension is used to achieve a smooth and constant driving quality, but in some instances, sports suspensions feature an air suspension system too. Similarly, air suspension replaces a conventional steel spring suspension in heavier vehicle applications, like trucks, tractor-trailers, passenger buses, and even passenger trains. Air suspension has also become popular in low-riding trucks like this gorgeous 1982 Dodge D200 Camper Special.

    What Is Electronically Controlled Air Suspension?

    According to the company now known as Dunlop Systems and Components, at the start of the 1990s, Dunlop developed and installed the Electronic Controlled Air Suspension (ECAS) system on the 1993 Range Rover Classic and again on the Range Rover P38A. The United Kingdom-based company developed the ECAS to include several key features:

    Vulcanized, heavy-duty rubber air springs at each of the vehicle's wheels

    An air compressor in the vehicle's trunk or under the hood of the vehicle

    A storage tank for compressed air, which allows you to store air at around an average of 150 PSI

    Valve blocks which direct air to the four springs from the storage reservoir through a set of solenoids, valves, and o-rings

    ECAS computer that communicates between the vehicle's main computer to calculate where to direct air pressure

    Air pipes connecting from the storage tank to the air springs that channel the flow of air throughout the suspension system

    A desiccant-filled drier canister to keep the internal recesses of the system dry

    The electronically controlled air suspension also features height sensors that are based on sensing resistance in contact with the terrain on all four of the vehicle's corners to provide height reference for all corners. Additionally, further advancements are beginning to feature some Electronic Control Units (ECUs) that are able to fit under the vehicle's floorboard, making air suspension more widely featured in everyday driving.

    The Benefits and Drawbacks of Air Suspension Systems

    According to Future Marketing Insights, the total value of the air suspension market at the end of 2017 was around $4.3 million. So whether it's a manual or electronic air suspension system, the benefits can greatly improve the ride of the vehicle. Take a look of some of the benefits of air suspension:

    More driver comfort due to the reduction in noise, harshness, and vibration on the road that can cause driver discomfort and fatigue

    Less wear and tear on the suspension system due to reduced harshness and vibration of heavy-duty driving

    Trailers last longer with air suspension because the system components don't take on as much vibration

    Front air suspenions reduce the tendency of short wheelbase trucks to bounce over rougher roads and terrain when the vehicle is empty

    Air suspension improves the ride height based on the load weight and a vehicle's speed

    Higher corner speeds due to air suspension being better suited to the surface of the road

    Air suspension increases the transport capabilities of trucks and trailers by providing a better grip that levels the entire suspension. An air suspension system can also be adjusted for feel, so drivers can choose between a softer feel for highway cruising or a harder ride for improved handling on more demanding roads.

    In the case of hauling heavy loads, air suspension offers more consistency and keeps all wheels even. The air suspension system keeps trucks level from side to side, especially in cases where cargo is difficult to level. This results in reduced body roll when turning corners and curves.

    Even with the benefits of an air suspension system, Driving Tests New Zealand suggests several drawbacks. Some of these disadvantages that so and so reports include:

    The initial costs of purchasing and installing an air suspension system — air suspension can also sometimes reach three times the cost in repairs as a leaf suspension system over 10 years' time

    Fuel overheads for running compressors for occasionally pumping air to the correct pressure

    Fuel efficiency can suffer from the heavier weight of rear air suspensions over the weight of leaf suspension

    An air suspension system's vulnerability to air leaks can result in malfunctions

    Some of the drawbacks of air suspension systems are because of some of the mechanical issues they can be vulnerable to. Several of the common issues with air suspension systems that can require repair include:

    Rust or moisture damage from the inside that can lead to the air struts or bags to malfunction

    Failure of the air suspension tubing connecting the air struts or bags to the air system

    Air fitting failure resulting from initial fitting or infrequent use

    Compressor burn out due to air leaks in the springs or air struts from the compressor constantly engaging to maintain the proper air pressure

    Even with these common mechanical problems, the benefits can far outweigh the drawbacks.

    Understanding Compressors

    Compressors are mechanical devices used to increase pressure in a variety of compressible fluids, or gases, the most common of these being air. Compressors are used throughout industry to provide shop or instrument air; to power air tools, paint sprayers, and abrasive blast equipment; to phase shift refrigerants for air conditioning and refrigeration; to propel gas through pipelines; etc. As with pumps, compressors are divided into centrifugal (or dynamic or kinetic) and positive-displacement types; but where pumps are predominately represented by centrifugal varieties, compressors are more often of the positive- displacement type. They can range in size from the fits-in-a-glovebox unit that inflates tires to the giant reciprocating or turbocompressor machines found in pipeline service. Positive-displacement compressors can be further broken out into reciprocating types, where the piston style predominates, and rotary types such as the helical screw and rotary vane.

    In this guide, we will use both of the terms compressors and air compressors to refer mainly to air compressors, and in a few specialized cases will speak to more specific gases for which compressors are used.

    Types of Air Compressor

    Compressors may be characterized in several different ways, but are commonly divided into types based on the functional method used to generate the compressed air or gas. In the sections below, we outline and present the common compressor types. The types covered include:

            Piston

            Diaphragm

            Helical Screw

            Sliding vane

            Scroll

            Rotary Lobe

            Centrifugal

            Axial

    Due to the nature of the compressor designs, a market also exists for the rebuilding of air compressors, and reconditioned air compressors may be available as an option over a newly purchased compressor.

    Piston Compressors

    Piston compressors, or reciprocating compressors, rely on the reciprocating action of one or more pistons to compress gas within a cylinder (or cylinders) and discharge it through valving into high pressure receiving tanks. In many instances, the tank and compressor are mounted in a common frame or skid as a so-called packaged unit. While the major application of piston compressors is providing compressed air as an energy source, piston compressors are also used by pipeline operators for natural gas transmission. Piston compressors are generally selected on the pressure required (psi) and the flow rate (scfm). A typical plant-air system provides compressed air in the 90-110 psi range, with volumes anywhere from 30 to 2500 cfm; these ranges are generally attainable through commercial, off-the-shelf units. Plant-air systems can be sized around a single unit or can be based on multiple smaller units which are spaced throughout the plant.

    To achieve higher air pressures than can be provided by a single stage compressor, two-stage units are available. Compressed air entering the second stage normally passes through an intercooler beforehand to eliminate some of the heat generated during the first-stage cycle.

    Speaking of heat, many piston compressors are designed to operate within a duty cycle, rather than continuously. Such cycles allow heat generated during the operation to dissipate, in many instances, through air-cooled fins.

    Piston compressors are available as both oil-lubricated and oil-free designs. For some applications which require oil-free air of the highest quality, other designs are better suited.

    Diaphragm Compressors

    A somewhat specialized reciprocating design, the diaphragm compressor uses a motor-mounted concentric that oscillates a flexible disc which alternately expands and contracts the volume of the compression chamber. Much like a diaphragm pump, the drive is sealed from the process fluid by the flexible disc, and thus there is no possibility of lubricant coming into contact with any gas. Diaphragm air compressors are relatively low capacity machines that have applications where very clean air is required, as in many laboratory and medical settings.

        Helical Screw Compressors
    
        Helical-screw compressors are rotary compressor machines known for their capacity to operate on 100% duty cycle, making them good choices for trailerable applications such as construction or road building. Using geared, meshing male and female rotors, these units pull gas in at the drive end, compress it as the rotors form a cell and the gas travels their length axially, and discharge the compressed gas through a discharge port on the non-drive end of the compressor casing. The rotary screw compressor action makes it quieter than a reciprocating compressor owing to reduced vibration. Another advantage of the screw compressor over piston types is the discharge air is free of pulsations. These units can be oil- or water- lubricated, or they can be designed to make oil-free air. These designs can meet the demands of critical oil-free service.

PA Speaker Buying Guide

    How to Choose PA Speakers
        
            Achieving consistently high-quality live sound can be a challenge. Your choice of PA speakers can determine whether you’re mixing to make something good sound great or struggling to solve sound-reinforcement problems. There are three basic categories of PA systems: 
        
            Personal PAs 
        
            Medium-sized PAs
        
            Full-scale PAs
        
            Personal PAs consist of single speakers or mini speaker arrays, which serve as both main speakers and monitors. Medium-sized PAs consist of a pair of stand-mounted speakers on either side of the stage plus simple monitor wedges. Full-scale PA systems involve multi-speaker line arrays and complex monitoring systems.

            We’ve created this Sweetwater Buying Guide to provide you with the information you’ll need when you’re ready to invest in new PA speakers. Since there’s so much more to consider than what we can possibly cover here, give your Sales Engineer a call at (800) 222-4700 after checking out this guide. They can help you choose the best PA speakers for your situation.

    How Much Power Do I Need?

    At Sweetwater, we’re often asked how much power is required for a PA system. But the real question is “How loud do you need it to be?” as your power requirements will vary according to your situation. Are you performing low-volume acoustic folk or high-volume progressive metal? A classical presentation or an EDM performance? The size of the venue is also important, as is the number of people attending (human bodies make terrific sound absorbers). A medium-sized venue (250–500 people) may require 2,000 watts or as much as 20,000 watts, based on these factors.

    So, is it all about wattage? Not necessarily. After all, more power doesn’t necessarily mean more output. While a speaker’s wattage definitely affects its volume, its maximum SPL (Sound Pressure Level) is a better indicator of how loud the speaker can go. Understanding a speaker’s coverage angle is also important. A powerful speaker with a narrow coverage angle will reach fewer people than a less powerful one with a broader coverage angle. It’s also vital that you consider the speaker’s sensitivity, which is a measurement of its ability to effectively convert power into sound. In a nutshell, sensitivity refers to the SPL that a speaker can produce from a 1-watt signal at a distance of 1 meter. This sensitivity spec measures “efficiency” and is a strong indicator of a speaker’s loudness, which is why a less efficient 1,000-watt speaker isn’t necessarily louder than an efficient 500-watt speaker. In fact, a 500-watt speaker with a sensitivity of 98dB will actually be the same volume as a 1,000-watt speaker with a sensitivity of 95dB.

    soundbar

A TV or home theater speaker system in a single cabinet. Soundbar speakers are designed for apartments or venues where discrete speakers are not desired throughout the room. Self powered, soundbars often support a wireless subwoofer for maximum bass response, which can be conveniently located anywhere in the room. In the more sophisticated systems, "virtual surround sound" is produced by psychoacoustic effects that adjust the timing and volume of the various speakers. Some units bounce the sound off side and back walls, which can be effective in small rooms, while others do not rely on precise placement.

    The Soundbase

    A soundbase is a soundbar that is deeper and flat so the TV stand can be placed on it. See home theater, home theater speakers and home theater in a box.

    Why Ceiling Speakers Are Good (Worth It) For Surround Sound

    While I was remodeling my home theater, I decided to take a look at ceiling speakers to increase my surround sound, but I found they were going to take a lot of work. This got me wondering whether ceiling speakers were worth the hassle.

    So, are ceiling speakers any good?

    Ceiling speakers make a great addition to a home theater, particularly if you’re looking for a more immersive sound experience. They need to be specifically designed for ceilings, but they make an excellent addition to a surround sound setup.

    When Are Ceiling Speakers A Good Addition?

    It’s fair to say that not everyone’s home theater will benefit from ceiling speakers. After all, if you’ve only got a small room dedicated to your home theater, you might already have enough speakers.

    Also, if you live in a rented property, you might not be able to carry out the work necessary to install them. These are some of the situations when you’ll probably see the most benefit from ceiling speakers:

    1. They’re less messy

    Sure, speakers aren’t usually considered ugly, but many people prefer to minimize clutter as much as possible.

    If you’re building a home theater, you’ll inevitably have cables running everywhere, and so at least mounting your speakers in the ceiling means you have a few less cables to worry about.

    2. They’re a good way of completing a surround sound system

    You’ve already got a set of “normal” speakers (think bookshelf speakers or monitors) then you might not want to go out and buy a new surround sound system.

    Ceiling speakers are a potentially easier way of completing this, as you can mount them behind your seating area and use them as the rear channels.

    3. They allow you to be more flexible with your layout

    If you choose to mount your speakers in the ceiling, then you won’t have to worry as much about positioning your furniture around floor speakers.

    Not only will this mean fewer cables, but if you get swiveling ceiling speakers, then you’ll have plenty of hkmenspa over where to put your furniture.

    4. They give you a more immersive experience

    Surround sound is all about immersion, so why not get the most out of your home theater? Cinemas use ceiling speakers for the same reason, so it makes sense to splash out on some if you can.

    Woofers

    A woofer is a speaker that is sized and constructed so that it can reproduce low and mid-range frequencies. Woofers do most of the work in reproducing the frequencies you hear, such as voices, most musical instruments, and sound effects.

    Depending on the size of the enclosure, a woofer can be as small as 4 inches in diameter or as large as 15 inches. Woofers with 6.5-inch to 8-inch diameters are common in floor standing speakers. Woofers with diameters in the 4-inch and 5-inch range are common in bookshelf speakers.

    Tweeters

    A tweeter is a specially designed speaker that is smaller than a woofer. It only reproduces audio frequencies above a certain threshold, including, in some cases, sounds that human ears cannot hear but only sense.

    Because high-frequencies are highly directional, tweeters disperse high-frequency sounds into the room so that the sounds are heard accurately. If the dispersion is too narrow, the listener has a limited amount of listening position options. If the dispersion is too wide, the sense of direction of where the sound is coming from is lost.

    These are the different types of tweeters:

            Cone: A smaller version of a standard speaker.

            Dome: The voice coil is attached to a dome that is made of fabric or a compatible metal.

            Piezo: Instead of a voice coil and cone or dome, an electrical connection is applied to a piezoelectric crystal, which in turn vibrates a diaphragm.

            Ribbon: Instead of a traditional diaphragm, a magnetic force is applied to a thin ribbon to create sound.

            Electrostatic: A thin diaphragm is suspended between two metal screens. The screens react to an electrical signal in such a way that the screens become out-of-phase. This alternately attracts and repels the suspended diaphragm, creating the needed vibration to create sound.

    Mid-Range Speakers

    A speaker enclosure may incorporate a woofer and tweeter to cover the entire frequency range. However, some speaker makers add a third speaker that further separates the low-range and mid-range frequencies. This is referred to as a mid-range speaker.

    There are many ways to add new life to your music in the car, but new speakers offers one of the fastest and most cost-effective ways to upgrade your sound. We have what you need, whether you just want to replace your factory speakers or if you plan to install an amplifier and need speakers that can handle a lot of power.

    Shopping for car speakers can be confusing, so we try to make the process as straightforward as possible. Watch the video below for an overview on how to shop for new car speakers.

    Crutchfield makes it easy to shop for car speakers

    The first thing you'll need to do is use our vehicle selector to tell us what you drive. We'll ask a few questions and then show you the best options for your vehicle.

    The Crutchfield car speaker recommender

    Once you've told us what you drive, you'll find the car speaker recommender at the top of the car speakers category page.

    The recommender is a great tool that could land you the perfect set of speakers in minutes.

    How many car speakers do I need?

    There's no standard for the number of car speakers that are factory-installed in a vehicle. In fact, they seem to get more numerous every year as car makers introduce premium factory sound systems with perks like noise cancellation and simulated engine noise. But for this article, we'll stick to the basics.

    When replacing front and rear speakers, a good goal is to have a voice-matched system. That means having the same brand and series of speakers in the front and rear. If you're on a budget, that doesn't have to happen all at once. Focus on your front speakers first. When you're ready, update the rear with speakers from the same speaker series (or at least, the same brand) for consistent sound characteristics.

    Speakers for the front of your vehicle

    Some vehicles only have two speakers in the front, one per door. They use a full-range design. Other vehicles feature four speakers in the front, two per side. This is typically woofers in the door and a tweeter either higher up in the door or in the corner pillar or dash.

    Many vehicles also have a center dash speaker, which typically handles vehicle essentials like door chimes and navigation prompts, in addition to playing music. Many people opt to leave the original speaker in this spot.

    Speakers for the rear of your vehicle

    Rear door speakers, rear deck speakers, and tailgate speakers are often full-range, although components have become increasingly popular. Rear speakers provide sound to backseat passengers and "rear fill" for the front row. Rear speakers generally don't make a significant contribution to the sound experience in the front seats. As a result they can be less important to drivers who don't have passengers very often or to sound enthusiasts who don't want any interference with their front soundstage.

    What size speakers should I buy?

    It's easy to feel overwhelmed by a long list of car speakers, all with different sizes. The good news is you don't have to sweat speaker size too much once you've told us what vehicle you're shopping for and whether you're shopping for front or rear speakers (or both).

    Sometimes you'll have a choice of a couple speaker sizes for a given location. In that case our rule of thumb is, "the bigger the better." So, given the choice between a 5-1/4" using a bracket or a 6"x9", we'll usually say go with the 6"x9" for more oomph.

    The finer points of fitting car speakers

    When looking at speaker fit, we're not just talking about the diameter of the speaker opening. We're also considering the allowable depth of that opening, sufficient room for the tweeter in front of the speaker, and several other factors. You can learn more about the details in our article about understanding speaker sizes. If speaker brackets are required to install your speakers, we'll include them.

    Full-range vs. components — what type of speakers should I get?

    Aftermarket car speakers can be divided into two main categories: full-range speakers and component speaker systems. Let's take a look at each.

    Full-range speakers

    Full-range speakers contain all the speaker elements in one basket. In their simplest form, they consist of a woofer for the lows, and a tweeter mounted onto the woofer to produce the highs. Some models will have additional drivers, like a midrange and/or supertweeter – these are referred to as "3-way" or "4-way" speakers.

Choosing a High-Resolution Graphic Design Monitor

    A graphic monitor is one of the most important pieces of hardware a design professional can buy. Look for the right technical specifications, including color accuracy, screen size, panel type, resolution, and more.

Use our guide below to streamline the process of buying a professional graphic design monitor. Or see how ViewSonic put it all together into making professional monitors. 

    Those new to graphic design may not place picking a graphic design monitor at the top of their priority list, but it might be the difference between success and failure. Graphic design is all about creating designs that leave lasting impressions and communicate a message to the viewer. In essence, it creates a bridge between the designer and the viewer.

    If you’re a graphic designer, then you know the ins and outs of the world of graphic design and the significance that presentation plays. Getting positive reviews on any form of graphic design work is all about how the design is visually presented. 

    What Are Graphic Design Monitors, and What Are They Good For

    Would you design graphics with your shades on? Probably not. Portraying the wrong colors on-screen is exactly why having the wrong monitor can be perilous to your work. As such, obtaining a high-resolution graphic design monitor is one of the best ways you can ensure that your work will stand out visually. Needless to say, this is one investment you definitely want to make for the sake of your career path as a graphic designer. 

    The Drawbacks of Graphic Design Monitors

    Before getting into the areas you should be looking into prior to purchasing an ideal graphic design monitor, let’s consider the drawbacks. 

    Oftentimes, when it comes to purchasing electronics, customers are duped into purchasing products with unnecessary features. Of course, avoidance of this issue is easier said than done. That said, it’s understandable. In today’s well-marketed and materialistic world, it is easy to find yourself wrongly swayed. Though, if you read up on graphic design monitors, the following factors should help keep your decision-making on the level. 

            Design
Don’t ever select a monitor simply because it looks cooler than the others. A monitor that is very slim may look attractive, but that’s pretty much as far as it goes. The graphic drawing pen monitor’s internal specifications are what determines how well it will perform, not the exterior. As they say, “don’t judge a book by its cover”, so too, don’t judge a monitor solely on its looks. 

            Bloated qualities
Built-in speakers, a good range of USB ports, and a proper TV Tuner shouldn’t distract you from considering a monitor’s internal setup. Even though these are great features for a monitor to possess, they do not guarantee an overall high-quality product. 

            Response time
If you are a certified graphic designer, as opposed to a professional gamer, response time shouldn’t really matter. Basically, the response time determines the time delay when a rapid action takes place on the screen. For gamers, as many actions are taking place on-screen within short periods of time, a good response time ensures the gamer’s ability to play at the proper speed, without lags on screen.

    What to Look for in Potential Graphic Design Monitors

    Serious graphic designers want a display that not only brings an optimal level of performance but also includes a high resolution. In today’s world of wireless connections, a good display is properly wired with the newest routes for connectivity. After all, the world runs on the ability to remain connected and linked. When it comes to purchasing the right monitor, a serious graphic designer knows that there’s more to it than simple numbers. That’s part of what makes ViewSonic’s VP line of monitors so attractive. 

    As with all other technology, purchasing a monitor requires you to do some background reading. While there are quite a few selections out there, unless you know the exact specifications, you might end up purchasing an LCD that doesn’t present your work with justice. 

    The following provides you with a list of things you want to consider before finalizing any monitor purchases.

A graphics drawing tablet used for sketching new images or tracing old ones. Also called a "graphic tablet," the user contacts the surface of the device with a wired or wireless pen or puck. Often mistakenly called a mouse, the puck is officially the "tablet cursor."
For sketching, either the pen or puck is used. For tracing, the puck is preferred because its crosshairs, visible through a clear glass lens, lets you precisely pinpoint ends and corners of detailed drawings.
Most tablets allow parts of the tablet surface to be customized into buttons that can be tapped to select menus and functions in the application.
Digitizer Mode and Mouse Mode
Tablets typically support two modes of operation. "Digitizer mode" creates a one-for-one correspondence between tablet and screen. Wherever the tablet is touched, the screen is drawn in the exact same location. In contrast, "mouse mode" moves the screen pointer (cursor) relative to any starting position on the tablet surface, just like an ordinary computer mouse.
The Output Is X-Y Coordinates
When drawing or tracing on the tablet, a series of x-y coordinates (vector graphics) are created, either as a continuous stream of coordinates, or as end points. See pen tablet, tablet PC and touchscreen.

    What Are All-In-One Personal Computers?

    All in one Pc is like conventional desktop computer systems in terms of features and functionality. The only difference between an all-in-one vs. a desktop PC is the number of components. While desktops are comprised of the computer case plus a separate monitor, all-in-ones combine the display and the computer into one package. This consolidation gives the all-in-one computer system a smaller profile than a desktop computer system.

    What Are All-In-One PCs?

    The earliest form of computer displays used large cathode-ray tubes. Because of the size of the displays, computer systems were comprised of three key components: the monitor, the computer case, and the input devices.

    As the size of the monitors decreased and the computer market consolidated into IBM-compatible and Apple-compatible product lines, computer companies started to integrate the computer case into the monitor to create all-in-one designs. These first all-in-one computer systems were still large and cost more than a standard desktop setup.

    The most successful of the all-in-one personal computers was the Apple iMac. The original design used the cathode-ray monitor with the computer boards and components integrated below the tube.

    With the advent of LCD monitors for displays and mobile parts getting smaller and more powerful, the size of the all-in-one computer system has decreased dramatically. Now, the computer components can be easily integrated behind the LCD panel or into the base of the display.

    All-In-One vs. Desktop PCs

    Buying a desktop offers several advantages over purchasing an all-in-one PC. Many all-in-one PCs feature processors (CPUs), drives, memory (RAM), and other components designed for laptops. Such architecture makes the all-in-one compact, but they also hinder the overall performance of the system. Typically, these laptop components will not perform as well as a desktop benchmark.

    Another challenge with all-in-one computers is the lack of upgrade options. While most desktop computer cases can be opened to install and replace components, all-in-one systems feature a closed design. This design approach typically limits the systems to having only their memory upgraded.

    With the rise of high-speed external peripheral connectors such as USB 3.0 and Thunderbolt, internal upgrade options are not as critical as they once were, but they still make a difference for some components such as the graphics processor.

    All-In-Ones vs. Laptops

    The all-in-one is smaller than a desktop, but it still is tethered to a desktop space. Laptops, conversely, move between locations and supply power through their battery packs. This portability makes them more flexible than the all-in-one.

    Because many all-in-one PCs use all the same components as laptops, the performance levels are mostly identical between the two types of computers. The only advantage that an all-in-one PC might hold is the size of the screen. While all in one drawing Pc generally come with screen sizes between 20 and 27 inches, laptops are still generally restricted to 17-inch and smaller displays.

    All-in-one systems used to be less expensive than laptops, but with technological advancements, the tables are now almost turned. You'll find many laptop computers for less than $500 while the typical all-in-one system now costs roughly $750 or more.

    How Wacom Tablets Work

    Let's get our definitions straight here, folks: Unlike the iPad, the Kindle Fire or the Nook, online teaching graphic tablet is not your average tablet PCs. Nor do they strive to be -- they're graphics tablets (also called pen tablets), devices generally used in the graphic design industry or by digital artists that allow a person to draw by hand, capturing an image or graphic in digital form. The information is displayed on the monitor of a connected PC or Mac.

    Sounds a little complicated, but imagine this: You're working at your computer when the fancy strikes you to doodle a picture of a cartoon chicken eating broccoli. (Doodles don't have to make sense.) You use the pen and paper next to you. After sitting there for a day or so, it's absent-mindedly put in the trash, only to decompose slowly in a landfill, your artistic genius never recognized.

    Unacceptable. Wacom tablets, which comprise many different models that we'll detail in this article, are designed so you can digitally doodle straight into your computer (among far more important tasks). Basically, they're the technological mating of a computer mouse with a pencil and a computer monitor with a college-ruled notebook.

    Not a perfect analogy. But graphic designers, artists, illustrators and many other hobbyists and professionals need a device that allows their hand-drawn work to be digitized or their digital image to be manipulated with an old-fashioned hand. The technology powering Wacom tablets provides a few advantages over click-and-point navigation. The pen, or stylus, that comes with the tablets can communicate much more effectively. Its pressure-sensitive system will let you determine things like how thick or thin a line should be, and it can instantly capture handwritten notations. The tablet communicates with the pen, plotting its location in microseconds as it makes your adjustments on screen.

    Graphic designers could benefit from the ease of turning concepts into digital reality. A photographer might like to be able to manipulate an image by hand more carefully. And pretty much everyone thinks it's cool to have their hand-written notes or doodles appear on their computer in the time it takes to put pen to paper.

    Unlike an iPad-like tablet, Wacom offers several different lines and models. Let's first take a look at the technology and hardware that's common to all of the tablets to grasp exactly how a Wacom tablet functions.

    We really have to start with the pen; Wacom refers to the pen's system as Penabled Technology. Sure, it looks like a regular pen but inside lurks a digital chip, a modulator and a transmitter. All of those components work in a complicated manner, but we can break it down: The tip of the pen tells the tablet what to do. And it's done with magnets! Well, not exactly. The sensor board of the tablet has a magnetic field, and the pen produces its own magnetic field -- and energy -- from it. (That's why no batteries or power adapter is needed.)

    The magnetic field emanating from the pen is recognized by the sensor board. From that, it can track the pen's location, pressure and speed. The sensor board itself is made up of a lot of little antenna coils, but it also has a control board that monitors the coils to determine where the current is (i.e., where the pen is). And that's what tells your computer that you want to add a moustache to the picture of your sister that you're photoshopping. Wacom calls this patented technology EMR, or electromagnetic resonance technology.

    It's a little different if an LCD screen is used, which is the case with the Cintiq line of tablets. In that case, backlighting or a component that gives off its own field could disrupt the pen's magnetic field. As such, all metal or problem parts must be tightly shielded to block out the field. The metal frame around the LCD screen -- which undoubtedly affects magnetic fields -- is accounted for in the control board, which recognizes a "weak" signal from the pen and corrects it so it follows a predictive course.

What Your Sunglasses Say About You

    Sunglasses are a real character builder. Or at least they play a large roll in the character that you play to others. They’re front and center and they can literally change the shape of your face. So before you buy your next pair of shades, think about what you might be saying to the world.

    With that said, here are some popular sunglass shapes along with what what they might be saying about your style.

    Sunglasses are one of the world's most ubiquitous fashion accessory, but also play an important part in protecting our eyes from harmful UV rays. The earliest known use of glasses to protect eyes from the sun was the Inuit use of “sun goggles” to shield their eyes from the blinding glare of light reflected off the snow. These were made from carved driftwood, bone, walrus ivory, or caribou antler that formed a strip worn across the eye area, with thin slits that the wearer could see through. The goggles were cut so that they fit tightly to the face, and often soot or gunpowder was rubbed on the outside to absorb the light and further cut down on glare. The use of these goggles dates back to around 2,000 years ago, and as a bonus, even improved the wearers vision as the narrow slits helped focus eyesight.

    unglasses protect your eyes from harmful ultraviolet (UV) rays, reduce eyestrain in bright conditions and protect you from flying debris and other hazards. Finding the right pair is key to your comfort, whether you’re driving to work or climbing a mountain.

    All acetate sunglasses offered at REI block 100% of ultraviolet light. UV protection information should be printed on the hangtag or price sticker of any sunglasses you buy, no matter where you buy them. If it isn't, find a different pair.

            Types of Sunglasses
       
            Casual sunglasses: Best for everyday use and basic recreational activities, casual sunglasses do an excellent job of shading your eyes from the sun while you drive to work and walk through town. Casual sunglasses are typically not designed to handle the intensity of action sports.

            Sport sunglasses: Designed for activities such as running, hiking and biking, sport sunglasses offer light weight and an excellent fit for fast-paced adventures. High-end frame and lens materials are more impact-resistant and flexible than casual sunglasses. Sport sunglasses also typically feature grippy nose pads and temple ends, a feature that helps keep the frames in place even when you're sweating. Some sport sunglasses include interchangeable lenses so you can make adjustments for different light conditions.

            Glacier glasses: Glacier glasses are special sunglasses designed specifically to protect your eyes from the intense light at high altitudes and sunlight reflecting off snow. They often feature wrap-around extensions to block light from entering at the sides.

            Sunglass Lens Features
        
            Polarized lenses: Polarized lenses substantially reduce glare. Polarization is a great feature if you enjoy water sports or are especially sensitive to glare.

            In some instances, polarized lenses react with the tints in windshields, creating blind spots and diminishing the visibility of LCD readouts. If this occurs, consider mirrored lenses as a glare-reducing alternative.

            Photochromic lenses: Photochromic lenses automatically adjust to changing light intensities and conditions. These lenses actually get darker on bright days, and lighter when conditions get darker.

            A couple of caveats: The photochromic process takes longer to work in cold conditions, and it doesn't work at all when driving a car because UVB rays do not penetrate your windshield.

            Interchangeable lenses: Some sunglass styles come with interchangeable (removable) lenses of different colors. These multi-lens systems allow you to tailor your eye protection to your activities and conditions. Consider this option if you need reliable performance in a wide variety of situations.

    The benefits of metal sunglasses

    If you prefer to keep it lightweight and classic, you can’t go wrong with sunglasses with metal frames.

    Metal frames are usually relatively thin, making them a great lightweight sunglasses option for everyday wear. Metal is also durable and resists corrosion. Metal frames also usually are outfitted with nose pads to help keep your sunglasses in place and prevent slippage (for a more comfortable fit). 

    Metal-frame sunglasses are typically made of aluminum, nickel, titanium or stainless steel, and come in a variety of styles, from iconic aviators to classic round frames. 

    When shopping for higher-end metal-frame sunglasses, consider aluminum and titanium. They’re both flexible, strong and corrosion resistant. Titanium sunglasses also are hypoallergenic, making titanium a great choice for those with skin sensitivities and allergies. 

    Metal sunglasses made from beryllium and stainless steel are also popular choices, due to their strength and resistance to corrosion. In fact, beryllium is especially appropriate for those who spend a lot of time in or around salt water and other abrasive environments.

    Do you play sports or wear performance sunglasses? Look for metal sunglasses made with monel or flexon. Both are exceptionally malleable, and flexon will return to its original shape after twisting or bending. 

    Note that metal sunglasses may not work for lenses that require a strong prescription. Due to their thinner frame construction, metal frames may be unable to accommodat

    WHAT IS TR90?

    TR-90 Sunglasses has been manufactured using TR90, an incredible new material that you’re sure to love. So what is TR90?

    TR90 was produced through Swiss technology as a thermoplastic material that is incredibly durable, flexible, and lightweight. Glasses made with TR90 are extremely comfortable because they have a flexible quality. Since they are flexible, they can bend under pressure and contour your face comfortably.

    This flexibility also makes TR90 glasses resilient to damage. Because the material is pliable, they are far less likely to break or bend from impact. If you’re guilty of constantly dropping your glasses, fear not! TR90 frames can prevail!

    Finally, and most remarkable of all, TR90 glasses are supremely lightweight! Even the boldest, biggest styles don’t feel bulky when made with TR90. The thermoplastic material has a barely-there feel that you truly have to wear to believe.

    How Your Glasses Can Become Your Main Accessory

    PC or CP sunglasses, although they are a necessity to some, don’t have to be a boring accessory to be stuck with. In 2020, we have seen a rise in popularity of amazing new glasses of all shapes and sizes. Don’t just stick with your old tired eyewear because you’re used to it; your glasses are the most noticeable accessory on your body, and they are the first thing people will see when they look at you. So, why not treat yourself to some cool, fresh glasses to revamp your look? Here is a short guide to help you along the way.

    Before Choosing Glasses

    It is so important to go for regular check-ups with your local eye doctor to see if anything needs changing in your prescription or if you have any eye health problems that need checking. You should go for an appointment at least every two years as not only could straining your eyes make your vision worse, it could be causing health problems like headaches and migraines too. If you have existing health problems with your eyes, you may have to visit slightly more regularly depending on the advice from your eye doctor.

    Good Quality Frames

    When looking for your next pair of glasses, it is so important to make sure you are getting some high-quality specs. Don’t be tricked by the price tag, as some extremely cheap glasses may not be very good quality and may break after a short time of having them. So, it is better to spend a little more to ensure you are getting the best quality you could possibly get. Sites like artofoptiks.com are experts in eyecare, and a great example of a supplier of high-quality glasses. There are so many on trend styles to choose from, so don’t limit yourself to basic frames.

    On Trend Eyewear Styles

    Transparent eyewear is definitely on the rise. Round shaped frames with transparent edging are such great alternatives if you just don’t like the idea of having a frame color to match your clothes with all the time. On the other hand, slightly tinted transparent frames are now becoming more and more popular, as they are like a slightly upgraded version of the clear version, with not so much color poking through, but just enough to give them a quirky edge.

    Geometric glasses are another alternative option shape wise. If you’re bored of the classic round shape, maybe give these a try as they almost imitate the rounded shape but with a slight edge. You can get all manner of geometric shaped glasses including square, hexagonal and even octagonal.

    Glasses a new fashion essential?

    Judging from the plethora of eye-catching eyewear that’s been getting face time over the last few years — be it on the European ready-to-wear runways or in the adjoining office cubicle — it’s clear that glasses have gone from nerd necessity to chic accessory.

    It’s a shift reflected in the current look-at-me trends — retro, vintage-inspired frames, chunky tortoise shells and geometric shapes that attract rather than deflect attention — and reinforced by the laundry list of fashion-focused brands with a presence in the eyewear arena. These include high-end European luxury labels like Prada, Giorgio Armani and Dolce & Gabbana as well as American contemporary brands Brooks Brothers, Tory Burch, Tiffany & Co. and Sperry Top-Sider, which aims to translate the brand’s footwear DNA into a line of licensed sunglass and ophthalmic frames due to hit the market next year.

    While it might seem logical to blame the deteriorating eyesight of the aging baby boomer population or the ever-increasing computer- and smartphone-induced strain on our collective eyeballs, consumer behavior statistics don’t show a jump in the number of people who need prescriptions. What they do show, however, is an increase in the number of people who wear glasses without prescription lenses — presumably to look cool.

    Dorothy Parker famously observed, “Men seldom make passes at girls who wear glasses.” How did we go from that image to bespectacled bombshells? How did eyewear go from the disguise that turns Superman into his milquetoast alter-ego to an individual expression of signature style?

    Some in the eyewear industry point to the traditional pop-culture petri dishes of Hollywood celebrity and fashion runways. “Maybe they’re seeing more celebrities” wearing glasses, said Larry Leight, co-founder and creative director of boutique brand Oliver Peoples. “And there are more … fashion magazines and runway shows where designers are accessorizing their shows with ophthalmic glasses — the kind that aren’t sunglasses — with either clear lenses or only slightly tinted colored lenses.”

    Milena Cavicchioli, vice president of marketing for Luxottica Group — the Milan-based eyewear company that owns Ray-Ban, Oakley and Oliver Peoples, among others, and which also makes eyewear and sunglasses under license for some 20 fashion labels — points to the recent Hollywood award show season as evidence. “Think of Meryl Streep on Oscar night,” Cavicchioli said. “She was wearing beautiful frames. And she’s not the only one. Jennifer Garner and Demi Moore are two I often see in clippings. When people are looking at [celebrities like] them to see what the latest trends are, them wearing frames is a huge support and endorsement.”

    She said there have also been other factors at work over the last half decade, including fashion designers’ approach to eyewear both in the frames that bear their names and in the styled looks that hit the runways during fashion week.

    “The [optical] collections themselves are becoming more elaborate,” she said. “There are some [styles] that are like jewelry pieces, that make a big fashion statement — like Prada’s Baroque frame, for example. The collections are being treated in a more fashion-forward way.”

    Fashion designers have realized just how powerful a brand extension eyewear can be, especially in comparison to some other offshoots. “It’s difficult for a brand to be visible with a fragrance because you’re the only one who knows what you’re wearing,” she explained. “But when you wear a pair of blue light glasses or optical frames, the brand itself gets exposure in the most prominent way because this is something you wear on your face. It’s not like a wallet that you put in your bag. I would say that it is as powerful as a [designer hand]bag as a brand statement, as brand exposure.”

    Not just a powerful statement, but an economical one too, points out David Rose, vice president of design and manufacturing at Costa Mesa-based Salt Optics. “A few years back, before the economy took a hit, people would spend a lot more money on their bags and their shoes,” Rose said. “But now eyewear is an accessible way to have a quality accessory.” Rose also said that switching out the spectacles provides a quick and easy way to create a whole new vibe. “It’s like getting a haircut — going from [having] long hair to buzzing your head — it really changes your overall look.”

    It’s not just the designers who’ve seen the value of cultivating the eyewear-as-fashion-accessory notion. Cavicchioli said that over the last five years Luxottica has increased its advertising in fashion magazines and worked to get its brands noticed by influencers and trendsetters. “We’re using the category to make a statement as well,” she said.

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Trenpro Technology: quality standard for switch plugs and sockets

    Trenpro Technology: quality standard for switch plugs and sockets

    What is the quality judging standard of switch plug and socket? Switch socket is used to deal with electricity, so it has a great relationship with the safety of power consumption environment. If you buy a poor quality switch socket, it is easy to cause electric shock and fire. Look at the quality of American standard switches and sockets. First look at the appearance, the appearance should be smooth, and the material should be uniform. Look at which material is used and whether advanced plastics are used. Good quality switch sockets usually use PC because the material has some flame retardancy, insulation and impact resistance, and it is not easy to change color.

    The quality of the switch plug and socket does not mean that the service life is long, so in addition to the quality, it also depends on the frequency of its use. The frequency of the use of switch sockets is standard, the national standard is 40000 times, some brands just conform to the national standards, some brands exceed the national standards, like the bull's switch sockets can be used 80000 times, is two times the national standard. That is to say, the service life of the same quality switch socket is different.

    Electrical strength: when the metal panel American 1 gang 2 way switch is disconnected, an electrical attachment with a nominal voltage of more than 130V should be applied with a sinusoidal frequency of 50HZ2000V for 1 minutes and no scintillation breakdown may occur. Electrical accessories with rated voltage above 130V specified in the socket shall be applied sine wave frequency North 50HZ2000V voltage for 1 minutes. No flashover breakdown will occur.

    What kind of switch socket is good when the quality and life span are quite good? It must be a high price ratio. Some people have always thought that the expensive is good, so the concept of consumption is wrong. The quality of the product is not rare, therefore, to buy the price is reasonable, in the quality, life and style of the same situation, the price can be considered.

    Guangdong Trenpro Technology Co., Ltd. is a manufacturer specializing in R & D, production and sales of XLR Carnon socket, Carnon plug, microphone socket, audio and video socket, mainly engaged in electronic components, automotive electrical appliances from new products to production and assembly to finished products.

    The current work is to conduct a design review on a multipurpose power socket for home application with the latest state of art features. Reviews are done in the areas of standard and codings, material selections, universal adapters, sensors and lighting technology. The standards for fabrication of BS 546 and BS 1363 plugs and sockets are essential for safety purposes. Together with selection of suitable material in production of plug and sockets, the occurrence of accidents can be averted. The invention of universal adapters was first coined by Rumble in year 1982 marks an evolution in the history of plugs and sockets. The main focus was to cater the different plug fixtures in various countries. Coupled to this, review works on the various types of sensors and lighting technologies is provided since it could be fused to the universal plug adapters for various applications. This paper then go on in proposing future works which could open new research pathways among worldwide researchers.

    Light is an important element in human’s daily activities as it provides brightness in the dark. There are varieties of light source that are being adopted in today daily life such as fire, halogen lamp, fluorescent lamp and light emitting diode (LED) lamp. LED has been chosen as one of the most common lighting systems due to the advantage in energy saving, better luminous and it can be used for a longer period of time. Sensors is also focused in current lighting technology. Sensors will act as a residential 1 gang 1 way 16a light switch for Homes and only be functioned as it detects the gesture related to its specification such as motion or darkness. The usage of sensor in lighting system will further improve the efficiency of the system and provides an alternatives for energy saving. 

    The review works will start with a brief overview on the standards and codings implemented, followed by the types of material used on the development of universal adapters and their applications. On the other hand, different types of sensors and lighting technology will be discussed in this work. Last but not least, proposed future works will be presented which could help to open new research pathways in the future.

    Standards are the regulations developed by International Standards Organizations (ISO). These standards act as the benchmark to be referred and used worldwide. Standards are documented to overcome differences among standards and technical regulations developed independently and separately by each nation or national standard organization. Codings is a set of rules that specify the standards that need to be followed to fabricate an object mentioned under the standard and codings.

    Plugs and wall sockets are the electrical components that connect together to allow the flow of electricity and thus complete the circuit. Plug and sockets are invented in Britain in the beginning of 1880s and designed to have only 2 pins at that time. The official standards then come in when the idea of interchangeable compatible devices were proposed. BS 1363 is the British standards that is used in United Kingdom and mostly the Commonwealth countries. It is a type of single-phase AC power plugs and sockets that can support a voltage up to 250V and a variety of ampere such as 2A, 5A, 13A and 15A.

    By referring to 13 A plugs, socket-outlets, adaptors and connection units, there are standards that need to be follow strictly in order to produce a marketable wall sockets with inspection on safety purposes. The sockets shall have marking the necessary information on the parts where it can be read and will not be easily spoiled. 

    There are specific safety requirements to be followed for BS 1363 wall adaptor. These can be divided according to 3 types of sockets which are 5A 3-round-pin adaptor, 12A 3-rectangulat-pin adaptor and 15A 3-round-pin adaptor.

    5A 3-round-pin adaptors are referred to BS 546 as international standard. To design and manufacture BS 546, it must have protection from fuse-link conforming to BS 1362 together. Only an allowable current of not exceeding 5A is permitted for the operation of this adaptor. A 5A adaptor with not more than three 5A sockets protected by one 5A main fuse-link confirming to BS 646 or BS 1362 is permitted (International Organization for Standardization [ISO], 2007).

    For 12A 3-rectangular-pin adaptor, the fabricating and designing process should be based on the BS 1363 Part 3 standard. The 13A adaptor that has one or two sockets for 13A plugs conforming to BS 1363 Part 1 need not be fused. For multiway 13A adaptor that has more than two sockets for 13A plug conforming to BS 1363 Part 1, it should have a 13A fuse-link conforming to BS 1363 as protection. For multiway 13A adaptor that has one socket for 12A plug and another socket for 5A plug conforming to both BS 1363 Part 1 and BS 546, respectively, an appropriate fuse-link complying with BS 546 and BS 1362 should be used to protect the outgoing circuits through 5A sockets (ISO, 2007).

    While 15A 3-round-pin adaptor is manufactured and designed to BS 546 standard. A 15A adaptor is protected by fuse-link matching to BS 1362. Table 2 shows the number ratings and the current ratings of the socket configuration of 15A adaptor (ISO, 2007).

    The safety features of BS 1363 adaptor or wall socket is further enhanced with the usage of safety shutters. The safety shutters is used as such that when a plug is withdrawn from it, the white American power electrical double wall socket  contacts or the socket holes which carry current supply will be automatically closed. The shutters should be operated by mating the earth pin to the earth hole. The shutter for a particular socket aperture should not be able to closed the shutter for another socket aperture independently (ISO, 2007).

    Figure 3 illustrates the standard dimension used in fabricating a BS 1362 type wall socket (Saudi Standards, Metrology and Quality Org [SASO], 2010). The dimension of the sockets must be strictly followed to ensure that the plug will fit firmly to the socket when using it to avoid accidents to be happened.

    In Malaysia, the fabrication and manufacturing of wall sockets must follow the information booklet of Approval of Electrical Equipment (Electricity Regulation 1994).This regulation is established by Energy Commission Malaysia under the Energy Commission Act 2001 [Act 610]. Under this regulation, a socket outlet is described as an electrical device that is fixed at a point at which wiring terminates. It provides a detachable connection with the pins of a plug and it has two or three contacts with a maximum current rating of 15A. Table 3 shows the standard codes of wall socket used in Malaysia.

    The abbreviation of MS in Table 3 refers to Malaysia Standard, IEC refers to International Electrotechnical Commission and BS refers to British Standard. By ensuing the procedure of these standards, the respective vendor can apply for certification of approval for electrical equipment with SIRIM Berhard. Upon obtaining the certifications, the vendors’ product is labelled as approved regulated electrical equipment and can be sold in Malaysia’s market.

    Material selection is important in the fabrication works of a power socket. This is to ensure that the socket produced is durable and safe for its user. The main components of power socket are made up of plastics and brass. Plastics are used as the casing and inner structure for the socket. Brass is used as connectors to hold the plug pin to allow the flow of electricity to the electrical appliances.

    Plastics can be divided into two type of categories which are synthetic or semi-synthetic organic compounds and this type of plastics are mostly derived from petrochemical. It is made by building up from simple chemical substances. To ensure the plastics bonding are tougher, safer, and cleaner, polymers that build up plastics are added with complex blend of materials known as “additives” (Talbot, 1941). These include biodegradable plasticisers, flame retardants, and heat stabilizers. The grade of plastics used in socket manufacturing is mainly thermoplastics or thermosetting polymers. Thermoplastics are plastics that will not undergo physical or chemical change in their composition upon heated (Gilleo, 2004). Thermosetting polymers, on the other hand can melt and take shape only once. They remains in solid once they have solidified. There are few common plastics grade that are used in fabricating power socket.

    Phenolic is one of the plastics used in manufacturing process. It act as a good electrical insulators and able to withstand resistance against water, acid and most solvents. It has low thermal conductivity and rigid at room temperature. The normal operating temperature limit for phenolic molding is 150°C, but grades are available which will operate at up to 200°C for limited periods. These properties allow it to be used in electric appliances industry (Black, 2010). There are two main production methods. One reacts phenol and formaldehyde directly to produce a thermosetting network polymer, while the other restricts the formaldehyde to produce a prepolymer known as novolac which can be molded and then cured with the addition of more formaldehyde and heat (Gardziella, Pilato, & Knop, 2000; Hesse, 2004).

    Melamine formaldehyde, or melamine is another type of plastics that is used due to its strong and glossy properties. Melamine shows good resistance to heat, chemicals, moisture, electricity and scratching which makes it to have excellent molding properties in producing power sockets and plugs (Black, 2010). Melamine formaldehyde was discovered by William F. Talbot and patent was applied on 12 December 1936 (Talbot, 1941).

    Another type of plastics that is widely used is polyimide. Thermosetting polyimide is one of the highest performing engineering plastics, with superior performance in applications under severe conditions. The properties of polyimide materials include:

    high temperature resistance that have operating temperature of 315°C,

    high wear resistance,

    low thermal expansion,

    good thermal and electrical insulation,

    relatively easy to machine,

    With this properties, thermosetting polyimides are used in various types of manufacturing industries including automotive, electrical appliances, aircraft and aerospace (Black, 2010). These materials tend to be insoluble and have high softening temperatures, arising from charge-transfer interactions between the planar subunits (Liaw et al., 2012).

    Brass is the material used as the electrical conductor inside the wall socket. Brass is a material that is made of copper and zinc. Copper-zinc solid solution alloy or brass retains good corrosion resistance and formability of copper but are relatively stronger (Fungal & Brody, 1996). Brass is used widely in the socket manufacturing due to its properties and it is a cheaper material compare to gold. Brass is generally soft which means that it can be machined without the use of cutting fluid, though there are exceptions to this (Faraday, 1832). Brass is used in situations where it is important that sparks are not struck, for example use as a fittings and tools that near flammable or explosive materials. CL 15000 99.85Cu-0.15Zr or zirconium-copper is one of the brass used in fabrication process. It has elastic modulus of 129 GPa and fatigue strength of 180 MPa. The density of CL 15000 is 8.89 g/cm3 and it has a liquidus temperature of 1080°C. The electrical conductivity of 93% IACS at 20°C. CL 15000 can withstand a temperature up to 1080°C before it melts 93% IACS shows that it is a good electrical conductor. Another similar brass or copper alloy, CL 15100 shows a similar properties as in CL 15000. This alloy is called ZHC copper and the elastic modulus is slightly smaller (121 GPa), the density is larger (8.94 g/cm3) and the liquidus temperature is the same at 1080°C. However, CL 15100 is a better conductor of electricity with 95% IACS if it is annealed and 90% if it is rolled with volumetric at 20°C (Fungal & Brody, 1996).

    The material used for doing the conductors inside wall socket but be able to withstand overheating. If the holders are getting hotter relative to time, there will be a risk of fire. The heating comes from the current which is drawn by the appliance and the resistance of the conductor. The plug pin will be inserted to or removed from the socket when using it. If the material wears too much, the holder may not be able to hold the plug pins firmly. Besides, the material used must be in low cost to keep the material and processing costs down.

    The material used to fabricate an electrical wall socket is crucial in safety purposes. Failure of the material used may possess danger like electrical sparking. Types of plastics used must be a good electrical insulator to avoid the electricity to be channelled into area other than the socket holes that fit in electrical plug. Types of brass used must have good ductility to ensure that the holder of the socket will always mate with the plug pin tightly and allow electricity to flows through efficiently.

    By selecting the right material in fabrication, problems like electrical sparking can be avoided. Electric sparking is an abrupt electrical discharge that occurs when a sufficiently high electric field creates an ionized, electrically conductive channel through a normally insulating medium, often air or other gases or gas mixtures. Faraday described this phenomenon as “beautiful flash of light attending the discharge of common electricity (Faraday, 1832). By rapid transitioning of electric field from a non-conducting to a conductive stats, it will produce a brief emission of light and a sharp crack or snapping sound.

    Fire is one of the major disasters around the world and electrical fire is the leading type of fire in terms of occurrence rate. An analysis is done in China and the leading type of fault resulting in major electrical fires is short circuit (43.89%) while the second leading fault is loose contact accounting for 8.89%. The second type of faulty is more difficult to discover as it is always covered by some illusions including short circuits. A study to such fires also known as sparking was conducted by Zi-Bo, Man, Chang-Zheng, and Ming (2011). First, two different types of loose contact fault, contact area reduction and contact vibrations are simulated tested and the temperature and some electrical parameters of contact resistance are tabulated during the testing. With this results, the characteristic identification criterion for loose contact is proposed (Zi-Bo et al., 2011).

    In the experiment, plugs and American style single 3 pin socket of rated current 10A are used under conditions of reduction and contact areas and contact vibrations. External heating temperature of 100°C, 200°C, 300°C, 400°C, 500°C, 600°C and 700°C are used to determine the characteristic law of samples. Apparently the plastics insulations of shells are melted and deformed while the metal parts are carbonized but there is no sign of melting and deformation. From the analysis results, it can be concluded that under fault over a small contact area, the plug’s terminal could reach a temperature of 300–400°C and the contact area between plug and socket can reach a temperature of 200–300°C. The major problem in sparking is after melting and carbonizing of insulation material of wall socket, secondary fault including combustion and short circuit may happen directly (Techakittiroj, 2008).

    The inductance of the wall sockets will result in creating sparks. When the outlet is unplugged, the inductance in the distributed system resists the change in the current. The path for the current has to be created and it is only active when the socket is unplugged. The rising voltage appears mainly at the outlet terminal and the major concern is to reduce the voltage at the socket. By reducing the voltage, the electrical sparks on the contact surface can be eliminated and this improves the socket lifetime. A capacitor is used to absorb energy from the inductance where the voltage will be regulated by the capacitor. By combining a capacitor with an inductor will result an oscillation at the voltage terminal and prolongs the durations of high voltage at the terminal. A resistor is used to damp the oscillation (Techakittiroj, 2008). Figure 4 shows the PSpice circuit for analysing a socket outlet.