The Kra pipe is a thermal winding pipe with a high-density polyethylene structure wall. HDPE winding structure wall pipe is a new type of special-shaped structure wall pipe. It is made through a high-density polyethylene thermal winding molding process. The products are mainly made of high-density polyethylene resin (HDPE) as raw material. The product uses PP or Pe bellows as auxiliary supporting tubes. It is high-density polyethylene large-diameter winding reinforced tubes produced by the thermal winding molding process. It is known as Kra pipe in China because this kind of pipe was originally imported from the German kra company. The official name of the product in China is high-density polyethylene structural wall thermal winding pipe. The national standard is GB/T 19472. 2-2017 B-type structural wall pipe.
The kra pipe can be divided into PR, OP, SQ, and VW series, among which: PR and OP are mainly used as buried drainage pipes. SQ is mainly used to make containers or inspection wells. VW is mainly used for pipe fittings formed by tee, elbow, and secondary processing. PR series is the most widely used in the products, which has a smooth inner surface and abnormal external reinforced structure. The standard length of the pipe is 6 meters. The inner diameter range of the pipe is DN300-DN4000, and the product indicators all meet the requirements of GB/T 19472.2-2017 type B structure wall pipe standard and EN-13476 European standard.
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