ASTM A335 P5 / UNS K41545 / 15Х5М Seamless Alloy Steel Pipe for High-Temperature Service

1. Product Introduction & Standard Specifications

This product is ASTM A335 P5 Seamless Alloy Steel Pipe, a seamless ferritic alloy-steel pipe specifically engineered for high-temperature service. It conforms to the Standard Specification for Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service (ASTM A335/A335M).

Pipes manufactured to this standard are designed to be suitable for bending, flanging, forming operations, and fusion welding. The ASTM A335/A335M standard covers several grades of ferritic (low and intermediate-alloy) steels containing up to and including 10% chromium. The specification is internationally recognized, with the latest version published in 2024.

• Standard: ASTM A335/A335M

• Grade: P5

• UNS Designation: K41545

• Russian Analog: GOST 550-2020 15Cr5Mo

• Manufacturing Process: Seamless

2. Material & Key Characteristics

ASTM A335 P5 pipe is a chromium-molybdenum (Cr-Mo) alloy steel. Its primary alloying elements provide a balance of high-temperature strength, resistance to oxidation (scaling), and improved corrosion resistance compared to carbon steels.

This material is defined as a ferritic steel, which provides good structural stability under prolonged exposure to high heat. It is a preferred choice for pressure-containing parts in elevated temperature environments due to its creep strength—the ability to resist deformation under stress at high temperatures over long periods.

3. Chemical Composition & Mechanical Properties

The following tables summarize the key technical specifications for ASTM A335 Grade P5 (UNS K41545).

Chemical Composition (Weight %)

Room Temperature Mechanical Properties

4. Typical Applications

ASTM A335 P5 seamless pipes are critical components in industries where equipment operates under high pressure and temperature. Their main application is in the construction of power generation and process industry piping systems.

• Power Generation: High-pressure boiler systems, including superheaters and reheaters, where steam temperatures can reach 450°C to 650°C.

• Petrochemical Industry: Refinery piping, heater tubes, and transfer lines for processing hydrocarbons at elevated temperatures.

• Oil & Gas: Pipelines and components in services requiring resistance to high-temperature corrosion.

• General High-Temperature Service: Any piping system requiring reliable performance in a sustained high-temperature environment.