Longitudinal Submerged Arc Welded (LSAW) steel pipes are often used in various industrial applications, and heat treatment can be an important step in their production process to improve their mechanical properties and ensure proper performance. Heat treatment processes for LSAW steel pipes usually include operations such as normalizing, tensioning and quenching and tempering. This article is a general overview of these heat treatment processes.
Normalization:
Objective: Objective: This process is aimed at enhancing the mechanical properties of steel by refining its grain structure.
Process: The steel pipe is heated above its critical transformation temperature and then cooled in the air. This process helps to achieve a uniform grain size that improves the overall mechanical properties of the pipe.
Stress Relieving:
The aim of this procedure is to decrease the residual stresses within the steel and enhance dimensional stability.
Process: Process: The steel tube is heated to a temperature below its critical range, held at that temperature for a specific period, and then slowly cooled. This process aims to alleviate any internal stresses induced during manufacturing, such as welding.
Quenching and Tempering:
Aim: To achieve a balance between hardness and toughness.
Quenching: The steel pipe is heated to a critical temperature and then quickly cooled, often by immersing it in water, oil or other quenching media. This produces a hard and brittle structure.
Tempering:
The previously quenched steel is then reheated to a lower temperature and held for a specific period of time. This process imparts toughness to the steel by allowing controlled reformation of the crystalline structure.
It should be noted that the heat treatment process and parameters can vary depending on the steel’s composition, intended use, and relevant standards or specifications.
Before implementing any heat treatment process, it is imperative to thoroughly scrutinise the material properties, welding techniques, and other pertinent factors to decide on the most appropriate heat treatment regimen for the specific application. Furthermore, stringent quality control measures must be in place to guarantee the precise and systematic application of the heat treatment.
Bestar Steel Co., Ltd is leading manufacture of LSAW steel pipes in China. For any further request, please contact: sales@bestar-pipe.com.
Post time: Nov-07-2023