Alloy Steel Pipes for Low-Temperature Service

• ​Introduction

Alloy Steel Pipes for Low – Temperature Service are specifically designed to operate in low – temperature environments. They are mainly used in industries such as oil and gas, petrochemicals, and refrigeration, where fluids need to be transported or stored at low temperatures. These pipes are made of special alloy steel materials, which can maintain good mechanical properties and structural integrity in extremely cold conditions, ensuring the safe and efficient transportation of fluids.

• ​Main Functions

Transport fluids in low – temperature environments: They are capable of transporting various fluids, such as liquefied natural gas (LNG) and other fuels, in extremely cold regions, meeting the transportation needs of different industries at low temperatures.

Ensure safety and reliability: With enhanced ductility, high impact resistance, and excellent weldability, these pipes can withstand stretching, deformation, and sudden impacts in cold environments, preventing accidents caused by brittle fractures and ensuring the safe operation of the pipeline system.

Maintain long – term performance: Even under continuous exposure to extreme cold, they can maintain their structural integrity, have low maintenance requirements, and provide long – term reliable service for low – temperature engineering projects.

• ​Tubing Standards

ASTM A333 ； EN 10216-4 ； GB/T 18984 .

• ​Material & Performance

Grade 3, Grade 6, Grade 7, Grade 8; 09Mn2VDG, 06Ni3MoDG, 06Ni9DG; 11MnNi5 – 3, 13MnNi6 – 3, X10Ni9;

They have enhanced ductility and can withstand tension and deformation in low-temperature environments. With high impact resistance, they can significantly resist sudden impacts in low-temperature applications and prevent brittle fracture. In addition, they also have excellent weldability and corrosion resistance.

• ​Manufacturing Process

Raw Material Preparation：High-purity alloy steel billets are selected and inspected for chemical composition and impurities.

Hot Rolling：The billet is heated and rolled into a hollow tube via a piercing mill, or extruded to form the initial pipe shape.

Heat Treatment： Normalizing：Improves microstructure and mechanical properties. Tempering：Reduces internal stress and enhances toughness.

Cold Drawing/Expanding (Optional)：Fine-tunes dimensions and surface finish for precise applications.

Non-Destructive Testing (NDT)：Ultrasonic testing (UT), eddy current testing (ET), and hydrostatic pressure testing are conducted to ensure freedom from defects.

Surface Treatment：Deburring, coating, and marking for identification and protection.

• Specifications