Welding Connection Alloy Stainless Steel Fittings Tee 310S Tee Round Head Code

Welding Connection Alloy Stainless Steel Fittings Tee 310S Tee Round Head Code

1.Introduction

Grade 310 is a medium carbon austenitic stainless steel, for high temperature applications

such as furnace parts and heat treatment equipment. It is used at temperatures up to 1150°C

in continuous service, and 1035°C in intermittent service. Grade 310S is a low carbon version

of grade 310.

2.Chemical compositions(%)

3.Fabrication

Grades 310/310S are forged in the temperature range 975 ~1175°C. Heavy work is

carried out down to 1050°C and a light finish is applied to the bottom of the range.

After forging annealing is recommended to relieve all stresses from the forging

process. The alloys can be readily cold formed by standard methods and equipment.

4.Application

Grade 310/310S is used in fluidised bed combustors, kilns, radiant tubes, tube hangers for

petroleum refining and steam boilers, coal gasifier internal components, lead pots,

thermowells, refractory anchor bolts, burners and combustion chambers, retorts, muffles,

annealing covers, saggers, food processing equipment, cryogenic structures.

5.Properties

These grades contain 25% chromium and 20% nickel, making them highly resistant to

oxidation and corrosion. Grade 310S is a lower carbon version, less prone to embrittlement

and sensitisation in service. The high chromium and medium nickel content make these steels

capable for applications in reducing sulphur atmospheres containing H2S. They are widely

used in moderately carburising atmospheres, as encountered in petrochemical environments.

For more severe carburising atmospheres other heat resisting alloys should be selected.

Grade 310 is not recommended for frequent liquid quenching as it suffers from thermal shock.

The grade is often used in cryogenic applications, due to its toughness and low magnetic

permeability.

In common with other austenitic stainless steels, these grades cannot be hardened by heat

treatment. They can be hardened by cold work, but this is rarely practiced.