Bimetallic pipe---mechanical combination

The main production processes of mechanical compounding include hydraulic compounding, cold drawing compounding, underwater deflagration compounding and cold rolling compounding.

Forming is based on the elastic-plastic characteristics of metal materials, that means, the elastic deformation range of outer base pipe (generally carbon steel seamless pipe) and the low yield strength of inner liner pipe (generally stainless steel pipe) are used. Under the external force, the inner tube is continuously deformed plastically, and the outer tube is always kept within the elastic deformation range. When the external force is removed, the outer tube shrinks elastically, and the inner tube cannot shrink due to the plastic deformation，which causes the outer surface of the inner tube to be strongly embedded in the inner surface of the outer tube.

Finally, the inner and outer pipes are in the state of interference fit, forming a close mechanical combination.




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