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Laboratory Testing
Laboratory tests have been developed to characterize the important physical properties of plastics to help guide design and production. The table below shows the ISO and equivalent ASTM tests which are widely applied to rigid polyurethane foams.

Standard Tests of Rigid Polyurethane Foams
ISO Number	ASTM Number	Physical Properties Measured
844	D 1621	Compressive stress-strain
2581	C 518	Thermal conductivity, Flowmeter
2582	C 177	Thermal conductivity, Hot Plate
5490	D 2856	Closed-cell Content

Rigid Foam Production for Pipe Supports
Rigid polyurethane components are produced by mixing two liquids; polyisocyanates and a mixture of polyol, catalysts, water and/or a blowing agent, pigments and other additives. Companies with experience in blending these chemicals can tailor them to the specific application. When the chemicals are combined under controlled conditions, an exothermic reaction begins and the foam begins to expand. With proper control of conditions the reaction continues to completion and a solid product is obtained.

The primary factors which manufacturers must control are temperature, accurate metering of the liquids, mixing, curing time and freedom from contaminants. Many machines have been developed for manufacturers to use for both control and efficient production. At Piping Technology we use RIM (Reaction Injection Molding) machines which provide excellent mixing, temperature control and metering of the chemicals. Our large inventory of molds give us the ability to provide proper geometry with a minimum of waste, reproducible results and maximum productivity of the workforce. Assembly line techniques can be applied when quantities justify this approach. The cure time before de-molding depends on the size of the component being produced.

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