Characteristics, Applications, and Standard Specifications of 16MnDG Low-Temperature Seamless Steel Pipe

First, Core Characteristics of 16MnDG Low-Temperature Seamless Steel Pipe

1. Excellent Low-Temperature Toughness of 16MnDG Low-Temperature Seamless Steel Pipe

Applicable Temperature Range: -45°C to 195°C. Some grades (such as 09Mn2VDG and 06Ni3MoDG) can operate as low as -70°C to -195°C, meeting the requirements of extremely cold environments.

2. Impact Toughness of 16MnDG Low-Temperature Seamless Steel Pipe: Maintaining high resistance to brittle fracture even at low temperatures, ensuring safe operation of pipeline systems. For example, 16MnDG meets the impact energy standard at -45°C, making it suitable for applications such as cold storage and liquefied natural gas (LNG) storage.

3. Stable Mechanical Properties of 16MnDG Low-Temperature Seamless Steel Pipe: Tensile Strength: 490-665MPa, Yield Strength ≥325MPa, Elongation ≥21%, meeting the pressure-bearing requirements of high-pressure pipelines.

4. Chemical composition control of 16MnDG low-temperature seamless steel pipe: Carbon: 0.12%-0.20%; Silicon: 0.20%-0.55%; Manganese: 1.20%-1.60%; Improve strength and toughness through alloy element ratio. Phosphorus: ≤0.025%; Sulfur: ≤0.025%, strictly limit impurity content to reduce brittleness risk.

5. Process and quality assurance of 16MnDG low-temperature seamless steel pipe

(1) Production method of 16MnDG low-temperature seamless steel pipe: hot rolling, cold drawing, hot expansion, delivery state is normalizing treatment, refining grain structure, improving low-temperature performance.

(2) Surface quality of 16MnDG low-temperature seamless steel pipe: smooth surface, no cracks, pores, and other defects, and reduced stress concentration points.

(3) Dimensional accuracy of 16MnDG low-temperature seamless steel pipe: outer diameter 21mm-762mm, wall thickness 3.0mm-130mm, covering different engineering requirements, and the deviation complies with GB/T18984 standard.

Second, the application fields of 16MnDG low-temperature seamless steel pipe

(1) Petrochemical industry

- Low-temperature oil and gas transportation: used for pipeline systems in cold areas or deep-sea oil and gas fields, such as Arctic liquefied natural gas projects.

- Pressure vessels: manufacturing low-temperature storage tanks, reactors, and other equipment to ensure sealing and durability under extreme temperatures.

(2) Energy field

- LNG storage and transportation: as a key material for LNG receiving stations, storage tanks, and transport ships, it can withstand a low-temperature environment of -162℃.

- Cold storage construction: used for refrigerant transmission pipelines to ensure low-temperature stability in scenarios such as food freezing and medical refrigeration.

(3) Chemical and heat exchange systems

- Low-temperature heat exchangers: used in chemical production to cool or heat low-temperature media, such as ethylene cracking units and air separation equipment. - Laboratory Equipment: Used as fluid transport pipes in cryogenic laboratories at universities and research institutions, they support research in superconductivity, low-temperature physics, and other fields.

Third, Implementation Standards and Certification for 16MnDG Low-Temperature Seamless Steel Pipes

- Domestic Standard: GB/T18984-2016, "Seamless Steel Pipes for Low-Temperature Pipes," specifies requirements for chemical composition, mechanical properties, dimensional deviations, and inspection rules.

- International Standard: ASTM A333 series (Grades 1 to 11), covering the requirements of different cryogenic grades and complementing GB/T18984.

- Type Testing: Products must comply with TSG D7002, "Rules for Type Testing of Pressure Piping Components," and undergo third-party testing and certification to ensure quality traceability.