Cold forming process

Kuzman, K., and Peklenik, J., 1990. Energy evaluation of cold-forming processes, CIRP Annals - Manufacturing Technology, 39 (1), 253-256. 

This is an extension of the cold forming process. It uses thermoformed B-stage thermoset reinforced plastic (RP) skin to improve surface and other characteristics to a cold molded thermoplastic. The mold is closed and the fast, room temperature curing RP plastic system hardens. The finished product has the smooth TP-formed sheet. 

Cold forming processes have been developed using a number of basic ideas, as follows. 

COLD FORMING PROCESS CAPABILITY CHART (RADIAL TOLERANCES ONLY)... 

Fig. 3.29 Comparison of automatic machining and cold forming processes for the manufacture of a plug body.

PROCESS MATERIAL. IMPACT EXTRUSION COLD FORMING COLD EXTRUSION SHEET METALWORK MACHINING POWDER METAL SINTERING... 

Pseudomorphism has less desirable consequences, and usually means are sought to suppress it. If the substrate has been scratched, ground or abrasively polished, or if it has been cold rolled or cold formed, the surface is left in a peculiar state. Cold working reduces the surface grain size, and produces deformed, shattered and partly reoriented metal. It may produce microcrevices between the deformed grains, and, with some processes, non-metallic impurities and oxides are embedded in the surface. The disturbed state of the substrate is copied by a pseudomorphic electrodeposit with several consequences (Fig. 12.7). One is aesthetic it has often been noted that almost invisible abrasion of the substrate develops as more prominent... 

Some ductile plastics, such as PC and ABS, can be fabricated like metals with punching and cold-forming techniques. These processing techniques are analogous to the hardness tests in that a rigid indentor is pressed into a sheet of a less-rigid plastic. 

Steel Carbon steel is the most common, least expensive, and most versatile metal used in industry. It has excellent ductility, permitting many cold-forming operations. Steel is also very weldable. The grades of steel most commonly used in the chemical-process industries have tensile strength in the 345- to 485-MPa (50,000 to... 

Unnilseptium, or bohrium, is artificially produced one atom at a time in particle accelerators. In 1976 Russian scientists at the nuclear research laboratories at Dubna synthesized element 107, which was named unnilseptium by lUPAC. Only a few atoms of element 107 were produced by what is called the cold fusion process wherein atoms of one element are slammed into atoms of a different element and their masses combine to form atoms of a new heavier element. Researchers did this by bombarding bismuth-204 with heavy ions of chromium-54 in a cyclotron. The reaction follows Bi-209 + Cr-54 + neutrons = (fuse to form) Uns-262 + an alpha decay chain. 

Cold-Water Process. The cold-water bitumen separation process has been developed to the point of small-scale continuous pilot plants. The process uses a combination of cold water and solvent. The first step usually involves disintegration of the tar sand charge, which is mixed with water, diluent, and reagents. The diluent may be a petroleum distillate fraction such as kerosene and is added in a ca 1 1 weight ratio to the bitumen in the feed. The pH is maintained at 9-9.5 by addition of wetting agents and ca 0.77 kg of soda ash per ton of tar sand. The effluent is mixed with more water, and in a raked classifier the sand is settled from the bulk of the remaining mixture. The water and oil overflow the classifier and are passed to thickeners, where the oil is concentrated. Clay in the tar sand feed forms emulsions that are hard to break and are wasted with the underflow from the thickeners. 

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