Nickel-base alloy clad pipe


Nickel-base alloy 625 is widely used because of its extensive corrosion resistance, excellent superheat resistance and fatigue strength, excellent tensile/creep deformation and fracture strength, and excellent weld ability. It is an excellent material to avoid localized corrosion (pitting and crevice corrosion), high corrosion fatigue strength, high tensile strength and resistance to chloride ion stress corrosion cracking in seawater. It is used for mooring cables, the blades of motorcycle gunboat propeller, submarine-assisted drive motors, rapid disengagement joints of submarine, exhaust pipelines of navy ship, protective jackets for submarine communication cables, submarine sensor controllers, and expansion joints of steam pipeline.

Performance Characteristics

1.       Adhesion strength between layers is more than 210MPa, adhesion rate is 100%
It completely solves the problem of weak adhesion strength of the layers that exits in the ordinary bimetallic clad pipe. The nickel-base alloy clad pipe whose outer material is pressure resistant metal pipe and inner material is 625 nickel-base alloy pipe. Combine these two materials with special processing technology which can not only resist corrosion but also resist high temperature. The adhesion strength between layers of ordinary clad pipe is 0.2MPa, it increases to more than 210MPa, by 1050 times, and adhesion rate is 100%.

2.       Withstand the same as or better pressure than that of seamless steel tube with the same sizes
The outer pipe is used as the backing steel to guarantee the safety of taking pressure. The inner pipe is used as functional part to make it more corrosion resistant. After comparing, nickel-base alloy clad pipe can withstand the same as or better pressure than that of seamless steel tube with the same sizes.

3.       Excellent machining property
The nickel-base alloy clad pipe has the excellent mechanical property, it can undertake all kinds of machining and adopt a variety of connections, such as welding connection, threaded connection.



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