Steel-lined PTFE pipes are soft and low in strength, and can be used as lining materials in the field of anti-corrosion. Generally speaking, there are two types of lining: coating and sheet. The melt fluidity of steel-lined PTFE pipelines is poor, and the coating must reach a certain thickness to meet the anti-corrosion requirements. The steel pipe lined with tetrafluoroethylene is the most corrosion-resistant pipe material developed after years of research. After years of testing, the tetrafluoroethylene lined steel pipe has the longest service life.