6 Major Processing Technologies for Seamless Steel Pipes for Structures

Seamless steel pipes are widely used in structural applications due to their strength and reliability. Here are six major processing technologies utilized in the production of seamless steel pipes:

Piercing Process:

This is the initial step in making seamless pipes where a solid steel billet is heated and then pierced to create a hollow tube. High-temperature furnaces are often used to heat the billets before they are placed in a piercer mill.

Pilgering:

After piercing, the hollow tube is elongated and reduced in diameter using a pilger mill. This involves a series of passes through a series of rollers and dies, which helps in achieving the desired dimensions and improved mechanical properties.

Rotary Piercing:

An advanced version of the piercing process, rotary piercing uses a roll-type piercer that rotates the billet as it is being pierced. This method improves the efficiency of the process and can produce pipes with better dimensional accuracy.

Cold Drawing:

Cold drawing is a process where the seamless pipe is pulled through a die at room temperature, allowing for fine-tuning of the dimensions and enhancement of mechanical properties such as strength and hardness.

Heat Treatment:

After forming, the seamless pipes often undergo heat treatment processes like annealing or normalizing. This is done to relieve internal stresses, improve toughness, and achieve desired mechanical properties.

Finishing Processes:

This includes processes such as hydrostatic testing, ultrasonic testing, and surface treatment (like pickling or coating) to ensure the pipes meet quality standards and are free from defects.

These technologies collectively ensure the production of high-quality seamless steel pipes suitable for structural applications, providing strength, durability, and reliability.