Gb9948 petroleum cracking pipe

Gb9948 petroleum cracking pipe

　　Gb9948 petroleum cracking pipes are mainly used to manufacture high-quality carbon structural steel, alloy structural steel and stainless heat-resistant steel high-pressure seamless pipes for steam boiler pipes with high pressure and above. These boiler pipes work under high temperature and high pressure, and the pipes will also undergo oxidation and corrosion under the action of high-temperature flue gas and steam. Therefore, the steel pipes are required to have high lasting strength High oxidation resistance and good tissue stability.

　　The hardenability of gb9948 petroleum cracking pipe has a great impact on the mechanical properties, but not all mechanical parts must be completely quenched. For example, shaft parts bearing bending and torsional stress and parts with surface heat treatment only need a certain depth of hardening layer to meet the service requirements.

　　The hardenability of gb9948 petroleum cracking tube mainly depends on the critical cooling rate. The smaller the critical cooling rate, the better the hardenability of gb9948 petroleum cracking tube. On the contrary, the hardenability of gb9948 petroleum cracking tube will be reduced. Except Co, most alloying elements can significantly improve the hardenability of steel.

　　It should be noted that hardenability and hardenability are two different concepts and should not be confused. Hardenability refers to the highest hardness obtained after quenching, which mainly depends on the carbon content in martensite. The hardenability of gb9948 petroleum cracking pipe with good hardenability is not necessarily high. For example, compared with low-carbon alloy steel, high-carbon tool steel has high hardenability but low hardenability, while the latter has low hardenability but high hardenability.