AN UPDATE ON THE USE OF RECYLED MATERIALS IN PLASTIC PIPING

摘要

Standards governing the design and materials used in plastic piping systems have been in existence for over 40 years. While many changes have been made to the standards and the manufacturing processes for these products, the single universal requirement across all product types has been the mandate to use virgin or internal rework material sources. This has been changing in recent years, due to federal government procurement guidelines as well as market demand. The specific cases cited in this paper reference poly (vinyl chloride) (PVC) piping systems, where the drivers for the use of recycle materials are federal mandates in some cases, and also a shortage of available virgin resin in the marketplace. The recycle content in the products may be achieved either by segregating the material into a coextruded layer, surrounded by layers of virgin materials, or by blending the recycle material with virgin and using it throughout the product. A history of the standards revision process and current activities is presented, along with sampling and testing schemes used to ensure the finished products will perform at or above the levels required of virgin materials.