Life and surface decarburization of spiral steel welded pipe is a definite link, if the rear surface decarbonization, spiral strength and wear resistance will reduce the direct impact on the spiral of life. If the carbon layer on the spiral steel welded pipe is not clean, the spiral surface layer hardness and wear resistance will be reduced accordingly, and the hardening process, because of the change in volume caused by the outer surface of the workpiece the formation of cracks.
How to prevent the spiral of decarbonization, here is the answer:
Solving the problem of surface decarbonization, mainly to be treated for the heat treatment process, because oxidation and decarbonization and the spiral are at the same time, so in the process of heat treatment, we should try to keep coils and air contact, This improves the decarburization phenomenon.
Resulting in spiral surface decarbonization media primarily oxygen, water vapor, carbon dioxide, and other oxidizing gases, when these gases and heated spiral contact can cause oxidation and decarbonization spiral, therefore, controlling the furnace and carbon dioxide carbon monoxide ratio is also very important.
In fact, added to the spiral forging furnace protective gas nitrogen is very effective, nitrogen can dispel some of the oxidizing gas, reducing the spiral of decarbonization phenomenon.