Bi-metal metallurgically-bonded seamless steel pipe

Composite pipe is a kind of engineering pipeline that develops rapidly in past decade abroad. It has wide varieties and functions.

Currently, bimetal composite pipes/tubes from domestic and oversea plants are mostly produced by mechanical methods (explosion forming, tube hydro forming, drawing, rolling etc.). Metal on both inside and outside layer is simply mechanical bonded. There are macroscopic gaps between two layers and could not meet the requirement of high-end users.

Metallurgical bonding bi-metal composite pipe/tube is the combination of primary industry material and high technology of metallurgical process. It realized the metallurgical bonding of multiple material and base material through the typical hot extrusion or hot extrusion and cold forming process, so as to obtain a high quality composite pipe. Meanwhile, as the pipe forming process is extrusion and the extrusion process is a three-direction compressive stress state, the difference of mechanical performance in vertical and horizontal direction is slight and the quality of pipe is excellent.

The metallurgical bi-metal composite tube&pipe is widely used in environment with high temperature and high pressure, strong corrosion, high wear and tear and other severe working conditions. For example, petroleum, chemical, refinery, gas, boiler, power plant, mining machinery, ship, vehicles and so on.

Superior performance

1. Inside and outside layer is metallurgical bonding, there is high bonding strength between base and multiple layers which is more than 300 MPa under normal conditions.
2. Cladding material could enhance strength and toughness of chosen base material and realize mechanical complementary.
3. Difference grades of base material enable the composite pipe to obtain different mechanical properties.
4. With different cladding materials chosen, the composite pipe could obtain characters such as high temperature resistant, high pressure resistant, severe environment resistant, wear resistant and so on, so as to extend the lifetime of composite pipe.
5. Even when there is cracking on the pipe because of chloride stress corrosion, the cracking will be stopped when it goes to the base material, as the good corrosion resistance of pipe interface could guarantee the safety of pipe.
6. The pipe obtains good ductility and big interface bonding strength. This makes it possible to reprocess the pipe freely, such as turning, cutting, tapping, heating, heating bending, pushing tee, reducing and so on.  

Please refer to below the photo of a turned part from a metallurgical composite pipe, the two layers remain solid concrete without any gap and cracking after turning process. This is what mechanical composite pipes could not achieve!

1. As it is metallurgical bonding between internal and external layers of the composite pipe, the pipe will be solid and enable the welding difficulty of pipe no difference with single metal pipe.

Metallurgical Bi-metal Composite Seamless Pipe available at Huaan International and the application: