PVC-lined steel pipe manufacturing business

One of our main focuses is on the production of PVC-lined, corrosion resistant steel pipes which are used for water and drainage.


Steel pipe input

After the acceptance, materials including steel pipes and PVC pipes are stored in each stocker. Stockers are divided by kinds and diameters. The steel pipes without primary anti corrosive treatment go through an automatic acid cleaning process with our facility.


Automatic cutting/Automatic PVC pipe insertion

Based on a production plan, materials including steel pipes and PVP pipes are automatically cut and moved out from the stockers. To insert a PVC pipe into a steel pipe, there used to be time loss due to jig change. However, our new facility eliminated the preparation step almost to zero and increased the production efficiency.


Induction heating/Infrared heat lining

Steel pipes are lined by quickly heating the surface of steel pipes with the induction heating (IH) method and conducting the heat to expand PVC pipes. Simultaneously, adhesive coated on the surface of PVC pipes is melted with the heat and the PVC pipe adheres to the inside of the steel pipe. The heating and speed requirements are converted into a program utilizing the accumulated knowledge of our company. Moreover, the ends of pipes later receive heat lining treatment with an infrared heater.


End treatment/Marking/Inspection

Excessive ends of aligned PVC pipes are cut and automatic polishing is applied. After processing end treatment and marking product names and others, the production is completed. Inspectors provide visual inspections to all pipes produced for the outside and inside on an inspection table. Furthermore, various physical property tests are conducted with our company’s testing machine for quality assurance.



Once pipes are produced for the number specified for each kind, they are bundled on a table and moved to storage. Bound products are shipped to meet customers’ requested delivery dates.


Nikken Sangyo product manufacturing processes