Do the inner and outer plastic-coated steel pipes need to be anti-corrosion and oiled

if the interior and exterior are fully coated with plastic, no anti-corrosion oiling is required. if the interior is plastic-coated and the outside of the pipe is only used for insulation, no anti-corrosion oiling is required. if the interior is plastic-coated and the outside of the pipe is directly exposed, anti-corrosion oiling is required.

the inner and outer plastic-coated steel pipes are made of polyethylene (pe) resin, ethylene-acrylic acid copolymer (eaa), epoxy (ep) powder, non-toxic polymer, etc. steel-plastic composite pipes are made of organic materials such as propylene (pp) or non-toxic polyvinyl chloride (pvc). pollution, fouling, low strength of plastic pipes, poor fire protection performance, and other shortcomings, the design life can reach 50 years.

the disadvantage is that bending is not allowed during installation, and during thermal processing and electric welding cutting, the cutting surface should be painted with non-toxic room temperature curing glue provided by the manufacturer to repair the damaged part.