253ma pipe

The chemical composition of 253ma stainless steel is balanced, makes 253ma pipe has the most appropriate comprehensive performance at 850 ℃ to 1100 ℃ temperature range: high resistance to oxidation, the oxidation of skin temperature as high as 1150 ℃;Extremely high variant variable capacity creep and creep rupture strength;In most of the gas medium has good resistance to high temperature corrosion and scale brush resistant ability;Higher yield strength and tensile strength at high temperature.

253ma pipe also have good formability and weldability, and enough to machinability. Besides element chromium and nickel alloy, 253ma stainless steel also contains a small amount of Rare Earth Metals, Rare Earth Metals, REM), so as to significantly improve its oxidation resistance.Nitrogen added to improve the creep properties and make this be fully austenitic steel.In spite of chromium and nickel content is relatively low, but this kind of stainless steel have many cases with high alloyed steel and nickel base alloy high temperature properties of the same.

253ma material equivalent grades:

253 ma chemical composition(%)

Corrosion Resistance

Although not designed for aqueous corrosion resistance, the high chromium and nitrogen contents give the grade a pitting resistance approximating that of 316. 253ma pipe does however have a high carbon content so is highly susceptible to sensitisation from welding or service exposure.

Heat Resistance

Oxidation - excellent resistance to air, at temperatures up to 1150°C. At high temperatures the steel quickly forms a thin, highly adherent and elastic oxide. This oxide gives good protection even under cyclic conditions.
Carburisation - Under oxidising conditions this grade can perform well, but alloys with higher nickel content are preferred if the atmosphere is reducing.
Sulphidation - good resistance to sulphur-bearing gases in an oxidising atmosphere, even if only traces of oxygen are present. Reducing gases prevent the protective oxide forming.
253ma stainless steel has high strength at elevated temperatures so is often used for structural and pressure-containing applications at temperatures above about 500°C and up to about 900°C. Its strength at these temperatures is higher than that of alternatives such as Grade 310.
253ma pipe will become sensitised in the temperature range of 425-860°C; this is not a problem for high temperature applications, but will result in reduced aqueous corrosion resistance.

Heat Treatment

Solution Treatment (Annealing) - Heat to 1050-1150°C and cool rapidly. It is recommended that the material be solution treated after 10-20% cold work to achieve maximum creep strength in service.
This grade cannot be hardened by thermal treatment.

Steel Making

Ingot Production

Forged Bars

Machinary

 

253ma pipe inspection