Manufacturing method of 17-4PH steel pipe

Abstract

17-4PH steel pipe manufacturing method includes the following steps: a. thermal processing and pipe blank heat perforating: heating temperature is 1090 ~ 1150 degree C and insulation time is 15 ~ 35 minutes; b. softening heat treatment: temperature is 650 ~ 700 degree C, insulation time is 4~5.5 hours; c. cold-working: cold rolling; d. softening heat treatment: temperature is 650 ~ 700 degree C, insulation time is 4 ~ 5.5 hours; e. acid-washing; f. repeating steps c ~ e cycles rolling until finished product size; g . finished product heat treatment: solid solution treatment 1020 ~ 1050 degree C +15 ~30 minutes, precipitation hardening treatment 450-630DEG C+3.5-4.5 hours, the finished product forms precipitation hardening martensitic structure with high strength and excellent corrosion resistance; h. finished product acid-washing. The invention replaces the original pipe elements art through boring and turning the pipe elements to reaching the required diameter and wall thickness with the technology of cold-working to getting the required diameter and wall thickness after heat perforating, it shortens production cycles, reduces production costs, improves product metal yield rate and increases economic efficiency.

Description

technical field [0001] The invention relates to a production method of pressure processing (pipe-making technology) of stainless steel seamless steel pipes in the metallurgical industry, especially a pipe-making technology of 17-4PH martensitic precipitation-hardening stainless steel pipes. Background technique [0002] Stainless steel seamless steel pipe is a metal product with a wide range of uses. It is often used in the fields of chemical industry, nuclear power, food, aviation and military. (2) Hot processing (extrusion, perforation) + cold processing, the solid tube blank is processed into a blank tube, and the blank tube undergoes subsequent cold processing and finishing processes: head → pickling → lubrication and then cold processing (cold drawing / cold rolling ) and degreasing→heading→heat treatment→straightening→pickling→lubrication→cold drawing (cycle cold processing to finished product specifications, and the quality of the finished product meets the required req...

AI Technical Summary

Problems solved by technology

Disadvantages: The equipment investment of the extrusion machine is large, the tool and mold are quite large, and it is rarely used in China

[0006] 2. Thermal perforation

Disadvantages: poor thermal perforation deformation conditions, poor variety adaptability

Disadvantages: the yield of waste pipe is low, and the yield of different wall thicknesses is 20% to 40%, and the processing cost is high, the cycle is long, and it is not suitable for mass production

[0013] The disadvantages of boring: low yield of raw tubes, 20% to 40% of different wall thicknesses, high processing costs, long cycle, not suitable for mass production

This fully shows that there is a certain degree of difficulty in the cold processing production of 17-4PH steel seamless pipes.

Images