The bi-metal composite pipe is a seamless steel pipe with an inner layer and a stainless steel pipe with a thinner wall thickness, and a carbon steel pipe or a low-alloy steel pipe such as a galvanized steel pipe or a welded pipe of the outer layer, which are strongly combined by a spinning composite process. A pipe is also a new type of more rational pipeline upgrade product.

It retains the characteristics and advantages of two different materials. It has excellent corrosion resistance of stainless steel, high mechanical strength and compression resistance, superior comprehensive performance and low construction cost. It is suitable for high requirements on conveying pipelines.

Medium. The inner liner serves as a corrosion-resistant effect, mostly stainless steel. Generally, different corrosion-resistant alloys can be selected according to the chemical composition of the transport medium. The wall thickness can be 0.3-4mm depending on the service life and welding process requirements.

The outer base pipe is responsible for the rigid support of the pressure and the pipeline, and generally selects the carbon steel pipe with different diameters and wall thickness according to the flow and pressure requirements of the conveying medium. The diameter can be from φ20-φ1020mm and the wall thickness can be from 2.5-50mm.The combination of the two materials retains the advantages and complements the deficiencies, and the traditionally mature installation method and process of galvanized steel pipes are also convenient, safe and reliable to use.