What are the precautions for hot processing of spiral steel pipes? Below is a small editor to take everyone to understand.
If the spiral steel pipe is heated with oil on the surface of the workpiece, the thickness of the oxide scale at the oil-attached part will be different from the thickness and composition of the oxide scale on other parts, and carburization will occur. The carburized part of the base metal under the oxide skin will be severely corroded by acid. The oil droplets sprayed by the heavy oil burner during the initial combustion will have a great influence if it adheres to the workpiece. The fingerprint of the operator may also be affected when it is attached to the workpiece. Therefore, do not touch the stainless steel parts directly with your hands, and do not make the work pieces stained with new oil. Must wear clean gloves to operate. If there is lubricating oil attached to the surface of the workpiece during cold working, it must be fully degreased in trichloroethylene degreasing agent and caustic soda solution, then cleaned with warm water, and then heat treated.
If there is residual oxide scale on the part of the spiral steel pipe before heat treatment, there will be differences in the thickness and composition of the oxide scale after heating, and the surface will be uneven after pickling. Therefore, not only the final heat treatment, but also the intermediate heat treatment and pickling. There is a difference between the oxide scale produced on the stainless steel surface that is directly in contact with the flame of air or oil and the place where it is not in contact. Therefore, it is necessary to prevent the treatment part from directly contacting the flame port during heating.
