Beginner's Guide to Manufacturing

Thermoforming Overview

Wed, 10 May 2006 22:41:28 +0000

Working in a manufacturing facility, you make all kinds of goods from various materials. These materials could be in the form of plastic or metal. It depends on the process, what products are required, the machines used, and what it is in demand. Irregardless of the need, the fact remains, everything has to go through a process. With metal the process is extrusion, but with plastic, the process is thermoforming. In order to perform thermoforming, you need to know the molecular structure of plastic and use equipment that adheres to the guidelines that have been established by the thermoforming industry. In order for the process to be successful there has to be certain elements in place. These elements fall into two categories:

• Materials: If the plastic that is used is bad, this could have an undesired affect on the final outcome. There are many types of plastic material available. When you deal with these materials, you have to be careful with them, that the material does not fall into one of these areas:
o Recycled plastic – Using recycled plastic has disadvantages. The recycled plastic has been shrunk to a certain point that there is not much left. However, using this type of plastic will not cause problems when using thermoforming. The thickness may be affected slightly, but not much else.
o Inconsistent materials – Another problem that can occur when working with plastic is inconsistent materials. This happens when the plastic ordered for production does not always have the same consistency and texture. In other words, the characteristics have been changed somewhat to keep it from being the same. This does not happen often but does occur every now and then.
o Specific thermoplastics – There are some plastics that are used for only certain manufacturing processes. These plastics are used to make certain plastic parts. When you purchase plastic materials, make sure you don’t get the wrong type for what you are doing.
• Lab Procedures: This second category is just as important because it emphasizes the way plastics are created and processed. This involves using the right machines and having trained people on those machines. If any procedure is not monitored carefully, mistakes can happen. Once a mistake happens, this can have an affect on the whole process. Therefore proper lab procedures must be followed. Here are some ways to ensure procedures are followed correctly:
o Quantify procedures – The best way to make sure that all procedures are followed correctly and consistently would be to document every step, by performing test analysis and finding what works best. After this is accomplished, write documentation based on these procedures. This should minimize any problems that could occur.
o Human intervention – Besides machinery, another reason procedures can fail is the lack of skills by the employees. If employees aren’t fully trained they can make mistakes which can cost the company big time.
o Temperature – Temperature is also a problematic occurrence that must be controlled. If the plastic being made is not put into the right temperature condition, the plastic will not harden or form correctly. Therefore, temperature is important.

What is Thermoforming?

Wed, 10 May 2006 22:42:43 +0000

Thermoforming can be described as a process where a thermoplastic sheet is formed into a three-dimensional shape. This is done by clamping the sheet into a frame, heating it in such a way to make it soft and pliable, then applying different amounts of pressure to mold the sheet into the shape of the die that is housed beneath the frame. If this pressure is applied by using a vacuum instead, it is called vacuum forming. Other methods of thermoforming include:

• Air pressure: This is where air pressure is applied to help preform the sheet can get it ready for the vacuum process.
• Mechanical pressure: This is where mechanical pressure is applied to a plug where it preforms the sheet (just like when using air pressure). The only difference is that the process is done by mechanical methods not by air pressure.
• Drape forming: This is the sheet is softened and lowered to drape over the high points of a make mold before the vacuum is used.
• Plug-and-ring: This is where a plug is used as the male mold and a ring matching the outside contour of the finished article is used.
• Ridge forming: This is where the plug is replaced with a skeleton frame and the whole process is done with this frame in place.

All these processes above do one thing – it uses thermoforming technology and procedures to get the plastic formed in the mold it is required.

Virtual Thermoforming - Going Virtual in a High-Tech World

Wed, 10 May 2006 22:43:41 +0000

Thermoforming is a process involving a machine where it alters plastics so they can be shaped into molds of various sizes and shapes that are used by different industries. The only problem with this method is if mistakes occur, the whole process has to be repeated again until the plastic is molded correctly. This can waste money and time. Two factors a business just can’t afford to lose. So what can be done to provide better resources and much better output? By using virtual reality thermoforming to ensure the process works correctly the first time.

Virtual thermoforming uses process simulation to evaluate a process to see whether it is feasible or not. Virtual thermoforming can detect if the manufacturer is using the right mold, material, and processing set up correctly. Because if the whole process of thermoforming is not done correctly, any part that is made could spell failure. Therefore, using simulation can help to make a plastic part better.

Unfortunately, in manufacturing today, there really is no time for failures. Because of this trial and error is out of the question. A process has to work the first time.

Simulation works by using a CAD model of a part or mold. The CAD model is downloaded into the simulation package. Or, if there is a programmer involved, the simulation can be built from scratch using simulation software. After the program is downloaded, the simulation program prompts the user to enter data into the screen. This data represents the behavior of the material. The user also enters the set up parameters including heater zone settings, sheet movement, plug assist, draw boxes, and cooling rate of mold. After all the data is entered into the program, the simulation package goes to work and provides a readout of what will happen were the process be done on a real machine.

Virtual thermoforming is catching on with many manufacturers. As the technology gets better, more companies will jump on the bandwagon.

Thermoforming Processing Troubleshooting

Wed, 10 May 2006 22:44:41 +0000

Thermoforming can produce plastic parts that work well with certain industries. However, just as with any other manufacturing process, mistakes and errors do occur that result in defective parts or materials. When this happens a solution has to be drawn to eliminate the problem so the whole operation performs without a hitch.

There are many things to look at when trying to resolve problems with defective plastics. This list is large, but only the most important problems and possible solutions are provided below:

• Incomplete forming: Another of things could cause this problem. For example, the temperature of the sheet could be too cold. Also, there could be insufficient vacuum. Another factor is a cold clamp frame or excessive draw. To resolve this you need to check for a non-functioning oven heater. Or you need to increase heating time. You can always increase the heater temperature. This will ensure the plastic is chilled to the right temperature. If this doesn’t work, replace the heater. You can also check for vacuum leaks or holes in the hoses.
• Sheet pulling out: This can be caused by insufficient clamp area, or force, or uneven heating. The best way to resolve this is to increase clamp area and force. You can also check the heater in the clamp frame area to make sure it is working correctly.
• Bubbles, blisters, or pits: This can be caused by the sheet getting too hot or there is too much moisture. The best way to resolve this is by protecting the sheet with moisture barrier wrap, or by storing the sheet in low humidity environments. Or you can preheat the sheet.
• Plug Sticking: If you are using a plug in your process and it sticks too much, this could be the result of the plug getting too hot. If this is the case, reduce the plug temperature, or use mold release agent or lubricant. You can always cover the plug with wool felt or cotton.
• Part Cracking: After your part has been made, you take it out and notice it has cracked; this could be the result of high internal stresses or improve part design. The best way to avoid this is to increase sheet forming temperature. This will help make the part quicker. You can also increase the radii.

Ultrasonic Cleaning Overview

Wed, 10 May 2006 22:45:43 +0000

One important aspect of manufacturing is making the product to be sold to customers. Every minute the machines are cranking away, producing what hopefully will turn into profits for the company. There could be ten to hundreds of machines running in a small space in the factory at any given time. All of these machines have one thing in common – they all get dirty. Pieces of metal or plastic can stick to parts of the machine at various locations in the machine. These pieces of material could accumulate to the point where damage could occur with the machine. How can this be avoided? By using a process referred to as ultrasonic cleaning. Ultrasonic cleaning is very helpful because it removes all the pieces of metal and other contaminants that could affect the performance of the machine. If you run a manufacturing facility and you don’t have ultrasonic cleaning at your place of business, you are risking damage to your machines or early wear that could have been avoided. If you are considering getting an ultrasonic cleaning system there are some factors to consider. These factors are:

• Ultrasonic power: In case you are not aware of this term, it means the amount of work that is done in any given time. For instance, ultrasonic power could be the time it takes to clean a machine effectively. This means making sure all debris is out of the machine and it is clean. Manufacturers of ultrasonic cleaning equipment may rate the power of their machines based on several criteria including peak power, RNS power, average power, ultrasonic power, cleaning power, and maybe even input power.
• Operating frequency: This factor cannot be overlooked. This is because the frequency of the machine affects the power of the machine. Some machines work at high frequencies while others work at low frequencies. Some even work in a mid-range of both. Another consideration regarding frequency is the amount of noise the machine makes. It the frequency is high, the noise level is non-existent. But if the frequency is low, the noise level can be unbearable.
• Cleaning solution: Here is another factor that must be considered. This is no doubt the most important one of all. Why? Because the solution has to be made of certain chemicals that it will do the job of cleaning the toughest areas and spots of the machine. The fluid has to have a high surface tension meaning it has more power to clean. Of course, the fluid also needs to have a low surface tension so as to go after smaller cavities. Therefore, the solution must have a balance of chemicals that can do both at the same time. Also, the chemicals must have the ability to hold debris in place as the fluid catches them. The last thing to consider about cleaning solutions is safety. The fluid must be safe enough to use in an industrial setting but will not hurt the person using it. This means the solution should not contain ammonia. Also, do not use phosphates. This harms the environment. And one that thing is it must be able to work well with water, or it is just wasteful.

What is Ultrasonic Cleaning and What is it used for?

Wed, 10 May 2006 22:47:20 +0000

For those of you who have never used it or heard about it, ultrasonic cleaning involves using high-frequency sound waves to remove contaminants from parts that have been immersed in a special cleaning solution. These contaminants can be anything including dirt, oil, grease, polish, mold release agents, and more. As for what type of materials ultrasonic cleaning can clean includes metals, glass, ceramics, and more.

Some applications of ultrasonic cleaning will depend on the industry and what has to be cleaned. This may be removing chips and cutting oils from cutting and machining operations. Other uses may be removing buffing or polishing compounds before plating begins. You can use ultrasonic cleaning to remove tough contaminants, but not harm the substrate. You can use it to clean the hardest to reach area.

How Does Ultrasonic Cleaning Work?

Wed, 10 May 2006 22:48:17 +0000

The whole process of ultrasonic cleaning is truly a blessing to manufacturers because no harsh chemicals are used to damage machines, their employees, and the environment. So when they have something to clean, they use ultrasonic cleaning to do it. So just how does ultrasonic cleaning work? Here are stages of how it works:

• Process: There is a process called cavitation. This is micron-size bubbles that form and grow due to alternating positive and negative pressure waves in a solution. What happens is the bubbles are subjected to these alternating pressure waves and grow until they reach a certain size. At this time there is a large amount of energy stored in the bubble itself. The temperature inside the bubble can reach very high with pressure readings of 500 atm. At this point the bubble implodes. When it does it is forced into the surface at speeds of up to 400 km/hr. At the point of impact, the bubble releases contaminants that are stuck to the substrate. Because the bubble is so small it can reach into the smallest of crevices and remove trapped debris, dust, and dirt easily and effectively.
• Ultrasound generation: In order for the positive and negative pressure waves to be produced, a mechanical vibrating device is needed. Many manufacturers who build ultrasonic cleaning systems use a diaphragm that is attached to high-frequency transducers. The transducers vibrate at a corresponding frequency that was caused by the high-frequency electronic generator source. This caused the diaphragm to vibrate at an amplified state. This amplified vibration is what causes the positive and negative pressure waves to occur. When this vibration occurs through water, these pressure waves create the cavitation process.

How is Ultrasonic Cleaning Machines Made to Work?

Wed, 10 May 2006 22:49:12 +0000

Now you know how the machine works, it would be a great idea to know what allows the machine to do what it does best. What does the machine use to get the job done? Here is some information about what makes the machine do what it does.

• Equipment: The main component that allows the machine to work is the bank of ultrasonic transducers that are mounted on a radiating diaphragm, an electrical generator, and a tank that is filled with the cleaning solution. The most important component of all these is the transducer. This is what generates the high-frequency mechanical energy. There are two transducers on the market that can be used – piezoelectric and magnetostrictive. They both have the same objective but perform differently.
o Piezoelectric transducers- These are made up of many components. There is usually a ceramic crystal that is sandwiched between two strips of tin. At the time voltage is sent across the strips, there is a displacement in the crystal. This is known as the piezoelectric effect. Of course, when you mount these transducers to a diaphragm, this displacement causes the diaphragm to move, which in turn creates a pressure wave that goes the solution that is in the tank. Unfortunately, these types of transducers have problems, one of which is that piezoelectric units deteriorate over time. Another reason is the transducer is mounted to the tank by epoxy adhesive which does give after a while. When it does the epoxy bond loosens causing the transducer to fall off.
o Magnetostrictive transducer – This type is known for its ruggedness and durability. These transducers are made of nickel laminations that are attached tightly together with an electrical coil that is placed over the nickel stack. At the time current flows through the coil a magnetic field is created. At this time the stack vibrates at the frequency of the current flow. The nickel stack is brazed onto the resonating diaphragm. This creates a solid metallic joint that never loosens.
• Ultrasonic generator: The ultrasonic generator converts the electrical frequency of 60 Hz into high frequencies of 20 to 80 KHz. Most systems today use what is called autofollow circuitry. This is where the generator matches the mechanical load with an equivalent electrical load, thereby providing optimum output at all times in the tank.
• Ultrasonic tanks: These are usually rectangular and are just about any size. You will usually find a transducer at the bottom or sides of the tank. A tank normally has a thickness of 11 to 14 gauge.
• The solution: This is a solvent is usually some kind of water-based detergent. Water alone is a good solvent because it is nontoxic, nonflammable, and environmentally friendly. But not all contaminates will come off with water. Therefore a detergent type solution is added to support better cleaning.

Contract Manufacturing

Tue, 01 Aug 2006 19:01:51 +0000

Contract Manufacturing Overview

The Process of Contract Manufacturing

Advantages and Disadvantages of Contract Manufacturing

Industries that Use Contract Manufacturing

Electronic Assembly

Tue, 01 Aug 2006 19:09:18 +0000

Electronic Assembly Overview

What is Electronic Assembly?

Setting Up an Electronics Assembly Factory

Where to Get Equipment and Parts

Precision Machining

Tue, 01 Aug 2006 19:11:31 +0000

Precision Machining Overview

What is referred to as Precision Machining?

What Kind of Machines are Used for Precision Machining?

Where to Get Machines for Precision Machining?

Heat Treating

Tue, 01 Aug 2006 19:20:49 +0000

Heat Treating Overview

What is Heat Treatment and How Is It Done?

What are the Processes Involved in Heat Treating

What types of Metals are Heat Treatable?

What is recycling?

Thu, 12 Oct 2006 17:37:27 +0000

Recycling is a process in which certain consumed materials can be reused to prevent the consumption of new materials, thus helping improve the environment. The process also eliminates waste, as some of the items which would normally be thrown away in the garbage can be recycled and put to good use. This is the universal symbol for recycling:

If you see this symbol on any product, it means that product is recyclable. Some of the most commonly recycled materials are paper, plastic, glass, aluminum and steel.

Recycling is usually pressed by the government especially during difficult financial times and times of war. The biggest worldwide push came during World War II, when every country involved in the war pressed its citizens to begin recycling, especially focusing on aluminum. Organizations like the Boy Scouts of America and many others began conscientious efforts to assist the country in its war by recycling all they could. Countries involved in the war which didn't have access to a plethora of natural resources, like Japan and some others, continued these strong recycling efforts even after the war concluded. As the 1970s arrived, the United States had another strong recycling push because of the rise in energy costs.

Several events during the 1980s were instrumental in increasing public interest in recycling and environmental assistance. In 1981, a city in Canada called Kitchener, Ontario, began a blue box recycling program. Households were given a blue box in which to discard glass, cardboard, aluminum, paper, and steel. In the last 25 years, the program has grown to the point that over 90% of households in Ontario utilize it, collectively recycling over 660,000 tons of waste each year. Ontario's program has inspired many other countries to follow suit, and now 40 million households from one side of the world to the other are using the blue box program or some variation of it.

In 1987, a barge containing 6 million pounds of garbage left New York and headed for Morehead City, North Carolina, to drop off its trash. While the barge, called the Mobro 4000, was en route, officials in Morehead City caught wind of a rumor that there some dangerous medical waste was among the trash on the boat, and they decided to reject its landing. The Mobro continued down the coast in search of a place it could unload it waste, eventually being denied access to both Mexico and Belize, as well. Finally, out of options, the barge returned to New York, and, after a pithy legal battle, the trash was incinerated. A bit of a media circus followed the long story of the Mobro, and Americans were somewhat fooled into thinking the country was short of landfill space (it wasn't really then, although it somewhat is now). This fear led Americans to become more interested in recycling and other environmentally safe programs.

Just two years after the Mobro fiasco, another event caused a recycling revival. A city in California called Berkeley banned the use of Polystyrene for the packaging of McDonald's sandwiches. This caused an uproar among the leaders at Dow Chemical, the world's leading Polystyrene manufacturer. These leaders decided to initiate major efforts to prove that plastics were recyclable. Just ten years later, nearly 1700 companies in the United States were involved in recycling plastics. It would be an understatement to say that the Berkeley officials' decision was instrumental in the discovery of the recyclability of post consumer plastics.

Why should I recycle?

Thu, 12 Oct 2006 17:38:12 +0000

Many of the products we use day in and day out are not biodegradable (meaning they will not safely eliminate themselves over time), so they take up valuable landfill space or must be incinerated, both of which are bad for the environment. Recycling creates a safer alternative, allowing some of these products to be reused for the same or similar purposes. Glass, plastic, and aluminum have almost limitless lifespan and can be used multiple times without ever losing quality. Paper, on the other hand, can be recycled, but it will lose some of its usefulness. The reason for this is that as fibers are recycled, they are shortened, causing them to not be as useful in higher quality products. Paper should certainly still be recycled, though.

Another possible incentive for recycling, albeit a greedier one, is financial gain. Many states (California, Oregon, Hawaii, Connecticut, Vermont, Delaware, Maine, Massachusetts, Michigan, New York and Iowa) offer a small refund on beverage containers (both bottles and cans) to give people more incentive to recycle. The refund in Michigan is ten cents per container, while it is five cents in all the other states. Many have had grand plans of taking a trip to Michigan with a vehicle full of bottles and cans to get the lucrative ten cent deposit, including the characters Kramer and Newman in the renowned television show Seinfeld. In a two part episode entitled "The Bottle Deposit," the two quirky characters use one of Newman's mail trucks to make the journey, which of course is foiled by numerous mishaps along the way. With gas prices today hovering around three dollars per gallon, it would be difficult to imagine anyone who doesn't live in Michigan having a good enough reason to take their recycling there.

A variation of recycling is simply called reuse. In recycling, the good material is reduced to raw material to make a new good material (for example, the glass bottle is crushed up and made into new glass). In reuse, the bottle would simply be refilled. (Don't worry, there is an intense method of proper cleaning in place anywhere bottles are refilled and reused.) This method of recycling is especially popular in many European countries, where as many as 98% of bottles are refillable.

How can I start recycling?

Thu, 12 Oct 2006 17:38:36 +0000

If you live in one of the states which offers a deposit, you will need to take your items to a recycling center (you can find one on the Internet or in the yellow pages). Sometimes department stores such as Wal-Mart will offer machines in which you place your items and a receipt is printed for you, which you then take to the customer service desk, where they give you your money.

If you don't live in one of these states, find out from your neighbors if they recycle, and ask them how to get started. Many cities will give residents a recycling bin which they can fill with recyclable materials and put out on the curb with your garbage. A separate truck will pick up these items and take them to the local recycling center. Remember, if you're having trouble deciding whether an item may be recyclable, look for the symbol pictured above somewhere on the item or the label...If you see that symbol, toss it in the recycling bin!

If you live in a state which doesn't yet offer recycling to its residents, it is time for you to act. Begin by writing your city officials (if you live in a neighborhood with an association, you may want to start there) and requesting that they provide the residents of your city with a bin in order to dispose of recyclable materials. As you approach your local officials, tell them it's an issue of three "E's": economics, efficiency, and environment. If it's not already at the top of their priority list, it should be well on its way there. As most cities and states already offer recycling, your best course of action may be to talk to your neighbors about whether they recycle. In 2002, only 16% of households in America were recycling the things they could, a number which is far too low.

Be proactive! Recycle everything you can, and talk to your friends, family, and neighbors about doing the same!