Surface infiltration process for seamless steel pipe piercing plug

Abstract

The invention relates to a surface infiltration process for a seamless steel pipe piercing plug. The surface infiltration process is characterized in that the treatment process comprises the following steps of annealing treatment, boronizing treatment, quenching treatment and tempering treatment; and by changing the parameters of a product in the quenching and tempering processes, by the adoption of air cooling at 1,060 DEG C, substrate tempered troostite after low-temperature tempering and martensite, the structure becomes wee, a boronized layer is further diffused, the thickness of an infiltrated layer is increased as the boron concentration of the infiltrated layer changes, the brittleness is improved, the measurement hardness is improved remarkably, and the service life of the piercing plug can be prolonged.

Description

technical field [0001] The invention relates to the technical field of seamless steel pipes, in particular to a process for infiltrating the surface of a seamless steel pipe perforated plug. Background technique [0002] The main mold used in the production of hot-rolled seamless steel pipes is also the main wearing part. Since the plugs work under the conditions of high temperature, high pressure and rapid cooling and heat, and are subjected to mechanical fatigue and thermal fatigue, the main failure mode of most plugs is cracking due to insufficient thermal strength and thermal fatigue performance, and the nose is not satisfied. production needs. In the GCr15 steel seamless steel pipe, the average life of the plug is 50 pieces. Due to the limitations of the heat strength performance and heat treatment quality of the existing plug material, its service life is not high, thus affecting the production efficiency and quality of the steel pipe. [0003] The existing plugs ar...

AI Technical Summary

Problems solved by technology

Due to the limitation of thermal strength performance and heat treatment quality of existing plug materials, its service life is not high, which affects the production efficiency and quality of steel pipes

[0003] The existing plugs are usually made of H13 steel and ductile iron. The main failure mode is that they cannot meet the production requirements due to insufficient thermal strength.

The service life of the pipe-piercing head of the seamless steel pipe made of high-strength materials such as GCr15 steel is particularly prominent. The improvement of the alloy composition of the existing H13 steel requires a large amount of investment, and there are a large number of problems to be solved.