Plastic Injection Molding Design and Manufacturing
Molded Urethane Parts Manufacturing
Urethane may be molded into virtually any shape, size and geometry.
Urethane is an excellent material which exhibits high
abrasion resistance and typically outperforms rubber,
plastic or metal in friction and impact environments.
Urethane exhibits has very good chemical resistance to most
solvents, chemicals, aliphatic based oils, and greases.
Selected Urethane formulations have excellent dimensional
stability over a broad range of temperatures and pressures.
Urethanes are also resistance to compression and tension
set . Selected Urethane compounds have very good
electrical properties , such as dielectric strength,
dielectric constant, and resistivity. Urethane is commonly
used as a insulating material.
Molded Urethane Parts
Classic mold design or plastic injection molding rules apply as urethane exhibits similar mold-ability properties. See Plastic Injection Molding.
The following are common custom molded urethane products:
urethane facilitates high impact, chemical, service abrasion
absorbing pads, bumpers and similar parts
Urethane (Ethyl carbamate) is a substance first prepared in the nineteenth century. Structurally it is an ester of carbamic acid, i. e., ethyl carbamate. Urethane itself is: (NH2-COOC2H5) and is not a component of polyurethanes.
Urethane is not acutely toxic to humans, as shown by its use as a medicine. Acute toxicity studies show that the lowest fatal dose in rats, mice, and rabbits equals 1.2 grams/kg. or more. When urethane was used medicinally, about 50 percent of the patients exhibited nausea and vomiting, and long time use led to gastroenteric hemorrhages (USEPA 1979). The compound has almost no odor and a cooling, saline, bitter taste.
Studies with rats, mice, and hamsters has shown that urethane will cause cancer when it is administered orally, injected, or applied to the skin, but no adequate studies of urethane-caused cancer in humans has been reported (IARC,1974). The International Agency for Research on Cancer has stated that urethane can be “reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity in experimental animals.” This evaluation has led to the following US regulatory actions:
NESHAP: Listed as a Hazardous Air Pollutant (HAP)
Comprehensive Environmental Response, Compensation, and Liability Act: Reportable Quantity (RQ) = 100 lb
Emergency Planning and Community Right-To-Know Act, EPA’s Toxics Release Inventory: A listed substance subject to RCRA reporting requirements
RCRA Listed Hazardous Waste: substance - U238