ASTM A312 TP347H Pipe | ASTM A312 TP347 Seamless Stainless Steel Pipe

ASTM A312 TP347H pipes and ASTM A312 TP347 seamless stainless steel pipes are niobium-stabilized austenitic stainless steel pipes designed for high-temperature, high-pressure, and corrosive service environments.

Manufactured according to ASTM A312, these stainless steel pipes provide excellent resistance to intergranular corrosion, oxidation, and creep deformation, making them suitable for long-term service under elevated temperatures.

TP347 and TP347H stainless steel pipes are widely used in:

• Oil refineries

• Petrochemical plants

• Power generation facilities

• Heat exchangers and boilers

• High-temperature process piping systems

We are a professional exporter and supplier of ASTM A312 TP347H seamless stainless steel pipe, SA312 TP347H pipe, and ASTM A312 TP347 stainless steel pipe.

What Is ASTM A312

ASTM A312 is the standard specification covering seamless, welded, and heavily cold-worked austenitic stainless steel pipes intended for high-temperature and general corrosive service.

This standard specifies requirements for:

• Chemical composition

• Mechanical properties

• Heat treatment

• Dimensional tolerances

• Testing and inspection procedures

Material Grades: TP347 and TP347H Stainless Steel

ASTM A312 TP347

TP347 is a niobium-stabilized (Nb) austenitic stainless steel that prevents chromium carbide precipitation during welding or exposure to high temperatures. This stabilization significantly improves resistance to intergranular corrosion.

Main characteristics:

• Excellent corrosion resistance

• Good weldability

• High oxidation resistance

• Suitable for elevated temperature service

ASTM A312 TP347H

TP347H is the high-carbon version of TP347 stainless steel, designed to enhance creep strength and high-temperature performance.

TP347H stainless steel pipes are commonly used in:

• Boilers

• Heat exchangers

• Petrochemical processing equipment

• Automotive and aircraft exhaust systems

• High-temperature chemical processing plants

By adding niobium (Nb) as a stabilizing element, TP347H improves structural stability and resistance to carbide precipitation during high-temperature operation.

This material performs best in sustained operating temperatures between:

800°F – 1500°F (427°C – 816°C)

TP347H is also an excellent choice for heavy welded components that cannot be re-annealed after welding.

ASTM A312 TP347 / TP347H Pipe Specifications

Standard
ASTM A312

Grades
TP347 / TP347H

Manufacturing Types

• Seamless pipe

• Straight seam welded pipe

• Heavily cold-worked welded pipe

Size Range

Outer Diameter: 10.3 – 762 mm
Wall Thickness: 1 – 50 mm

Length

• Random length

• Fixed length

Delivery Condition

• Solution annealed

• Pickled

• Passivated

Packaging

• Bundles

• Plywood cases

• Export seaworthy packing

Equivalent Material Standards

Chemical Composition of ASTM A312 TP347H (%)

Heat Treatment Requirements

Testing and Inspection

To ensure quality and compliance with ASTM A312 standards, the following tests are conducted:

• Flattening test

• Flaring test

• Hardness test

• Hydrostatic test

• Eddy current testing (ET)

• Ultrasonic testing (UT)

Optional inspections include:

• PMI (Positive Material Identification)

• Spectro chemical analysis

• Mechanical properties testing

• Radiographic testing for welded pipes

• Straightness testing

• Roughness testing

• Intergranular corrosion testing

• Impact testing

• Grain size determination

Surface Condition

Pipes can be supplied with the following surface finishes:

• Pickled

• Passivated

• Shot blasted

• Black phosphated

Example Order

ASTM A312 TP347H
14 inch stainless steel seamless pipe
Schedule 140
Length: 6000 mm