Fluidized bed technology consists of a tank or chamber with a porous plate at the bottom. The powder coating is placed in the tank, where it is agitated both by vibration and by air blowing through the openings in the porous bottom. The agitated powder fi lls the volume of the tank, into which is dipped a heated part. The part being coated is heated to a temperature approximately 100 ° F (about 56 ° C) higher than the fusion temperature of the powder coating. Parts as large as light poles can be coated by this method. The coating thickness is controlled by the residence time of the part in the tank.
(Weldon D.G., Failure analysis of paints and coatings, p. 128)
Dry Pressing
The moisture content of the starting clay in dry pressing is typically below 5%. Binders are usually added to the dry powder mix to provide sufficient strength in the pressed part for subsequent handling. Lubricants are also added to prevent die sticking during pressing and ejection. Because dry clay has no plasticity and is very abrasive, there are differences in die design and operating procedures, compared to semi-dry pressing. The dies must be made of hardened tool steel or cemented tungsten carbide to reduce wear. Since dry clay will not flow during pressing, the geometry of the part must be relatively simple, and the amount and distribution of starting powder in the die cavity must be right. No flash is formed in dry pressing, and no drying shrinkage occurs, so drying time is eliminated and good accuracy can be achieved in the dimensions of the final product. The process sequence in dry pressing is similar to semi-dry pressing. Typical products include bathroom tile, electrical insulators, and refractory brick.
(Groover M. P., Fundamentals of modern manufacturing: Materials, processes and systems 3rd edition, p. 368)
Ergonomics
Human factors engineering, or ergonomics,* as it is sometimes called, developed as a result of the experience in the use of highly sophisticated equipment in World War II. The ultimate potentialities of complex instruments of war could not be realized because the human operators lacked the necessary capabilities and endurance required to operate them. This discipline now has been extended to many areas. It is used extensively in the aircraft and aerospace industry and in many other industries to achieve more effective integration of humans and machines.
(Kutz M., Mechanical engineers' handbook 3rd edition: Manufacturing and management, p. 658)
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