ASME SA335 refers to P91 steel under the American ASME standard, also known as P91 martensitic heat-resistant steel or 91 steel.

ASME SA335 refers to P91 steel under the American ASME standard, also known as P91 martensitic heat-resistant steel or 91 steel. This is a seamless ferritic alloy steel used in high-temperature and high-pressure environments and is often used as a material for high-temperature and high-pressure pipes and components. During the manufacturing process of P91 steel, there are specific requirements for the content of other elements, and its mechanical properties, such as flattening tests, also need to meet specific standards. In addition, the surface quality of P91 steel also has certain requirements, such as all burrs must be removed, the pipe end must be smooth and burr-free, etc.

The chemical composition of ASME SA335 mainly includes carbon (C), silicon (Si), manganese (Mn), phosphorus (P), sulfur (S), chromium (Cr), molybdenum (Mo), tungsten (W), vanadium (V) ), niobium (Nb) and nitrogen (N) and other elements. The content and proportion of these elements are carefully formulated to ensure that ASME SA335 steel pipes have excellent high-temperature strength and creep properties, as well as good corrosion resistance and oxidation resistance. Among them, chromium (Cr) is an important alloy element that can improve the corrosion resistance and oxidation resistance of steel pipes; molybdenum (Mo) and tungsten (W) help enhance the high-temperature strength and creep performance of steel pipes; and vanadium ( Elements such as V) and niobium (Nb) can refine the grains and improve the strength and toughness of steel pipes.

The production method of ASME SA335 is mainly hot rolling. ASME SA335 seamless steel pipes also need to go through a series of complex process steps during the production process, including capillary preparation, pickling review, tool selection, annealing treatment and pickling to ensure that the quality and performance of the steel pipes meet standard requirements.

The characteristics of ASME SA335 are mainly reflected in the following aspects:

1. High strength and corrosion resistance: It has excellent strength and corrosion resistance, which makes it widely used in environments such as high-pressure boilers that need to withstand high temperatures and pressures.

2. Good thermal conductivity and fatigue resistance: It has good fatigue resistance, which helps ensure the safety and stability of the equipment.

3. High high temperature strength and creep strength: ASME SA335 seamless steel pipe can withstand high temperature and high pressure working conditions, mainly due to its excellent high temperature strength and creep strength.

4. Excellent anti-wear performance: It can effectively resist the erosion and wear of fluid media, reducing pipeline wear and maintenance workload.

5. Good welding performance: It facilitates welding processing and ensures the connection quality and reliability of the pipeline system.

ASME SA335 has a wide range of applications, mainly covering the fields of petroleum, chemical industry, electric power and boilers. In the petroleum and chemical industry, ASME SA335 seamless steel pipes are used to manufacture various reactors, heat exchangers, separators and other equipment, which need to withstand high temperatures, high pressures and corrosive media. In the fields of electric power and boilers, this kind of steel pipe is widely used in the manufacture of superheaters, reheaters, economizers and other equipment, which have strict requirements for high temperature and high pressure resistance.