Thick-Walled Seamless Pipe

• ​Introduction

Thick-walled steel pipes refers to a steel pipe with a large ratio of wall thickness to outer diameter (wall thickness coefficient). They exhibit high strength, pressure resistance, and stable comprehensive performance, making them suitable for industries such as petroleum, chemical engineering, and machinery manufacturing.

• ​Main Functions

High Pressure Resistance: High strength and reliability, suitable for extreme working conditions; Corrosion Resistance: Alloy and stainless steel variants withstand acidic, alkaline, and high-temperature conditions，Carbon steel pipe corrosion resistance can be improved through surface treatments (such as galvanizing and plastic coating); Flexible Processing:：Good processability, supporting welding, cutting, bending, and other processes.

• ​Tubing Standards

In the American standard system (e.g., ASME B36.10/B36.19), seamless steel pipes with a wall thickness schedule of Sch 80 or higher are generally referred to as “thick-walled pipes”. In the ISO, European (e.g., EN 10216), and Chinese (e.g., GB/T 17395) standard systems define thick-walled seamless pipes as those with an outer diameter to wall thickness ratio (OD/WT) ≤ 20.

• ​Material  

Seamless thick-walled steel pipes can be processed from various materials, and the specific materials can be determined through negotiation.

• ​Manufacturing Process ​

Hot Rolling ​； Cold drawn/Rolling ​； Heat treatment: According to the performance requirements of the steel pipe, conduct heat treatment on the rolled steel pipe, such as normalizing, tempering, quenching, etc., to eliminate the residual stress inside the steel pipe and improve its strength, toughness, hardness, and other properties. Inspection: Conduct a comprehensive inspection on the finished steel pipe, including the inspection of dimensional accuracy, appearance quality, mechanical properties, chemical composition, etc., to ensure that the steel pipe meets the relevant standards and customer requirements.