Development of polyurethane insulated steel pipe and high density polyethylene plastic. Antioxidants, UV stabilizers, carbon black (or carbon black masterbatch preparation) and other additives are used to promote the production of the outer protective tube and improve the performance of the outer protective tube. The addition of carbon black shall meet the following requirements: density: cubic meter; extraction amount of toluene: less than (mass percentage); Mimi

　　Average particle size of recycled materials: polyurethane insulation pipe can be used for cleaning recycled materials with no more than (quality), but the materials must use their own products. The volume of external protection pipe shall not be less than cubic meter. The content of carbon black shall be (mass percentage), and carbon black shall be evenly distributed in the matrix. The melt flow rate and melt flow rate are the values of the outer casing provided by the casing supplier. The longitudinal shrinkage of the inner wall surface shall be free of cracks, holes, bubbles and other defects. The long-term mechanical properties of the outer protective tube shall meet the requirements of the long-term mechanical properties.

　　The minimum wall thickness of the outer protection pipe shall be the same as the specified outer diameter and wall thickness, and the allowable deviation shall be the same as the specified deviation. When the outer protective tube is welded, the difference of melt flow rate shall not be greater than 2 /.

　　The outer protective tube shall be black, and there shall be no visual barrier on the inner surface and outer surface of polyurethane insulation tube. No bubble, crack, dent, impurity, uneven color and other defects. Both ends of the pipe shall be cut horizontally, perpendicular to the pipe axis, and the angle error shall be less than the degree. The tensile yield strength and elongation at break at any position shall not be less than. The longitudinal shrinkage of outer casing shall not be greater than the longitudinal shrinkage.

　　The above is the relevant content introduced by the small edition of polyurethane insulated steel pipe manufacturer. If you want to know more, please visit the website: https://www.sdhpgy.com