Home > Stainless Steel Pipes & Tubes>TP347LN Stainless Steel Pipes & Tubes

TP347LN Stainless Steel Pipes & Tubes


Material Description

UNS S34751

Chemical Composition, %


C

Mn

P

S

Si

Cr

Ni

N

Nb

.005-.020

2.0

.045

.03

1.0

17.0-19.0

9.0-12.0

.06-.10

.2-.5


TP347LN is an austenitic, niobium-stabilized stainless chromium-nickel steel with an extremely low carbon content for use at temperatures up to 850°C (1560°F).


Corrosion Resistance

TP347LN has with some limitations (nitric acid) the same resistance as the unstabilised steel TP304, i.e. the material has good resistance in:

● Organic acids at moderate temperatures

● Salt solutions, e.g. sulphates, sulphides and sulphites

● Caustic environments at moderate temperatures


TP347LN is generally used at temperatures above 500 °C (930 °F), however, where wet corrosion is not relevant.

The stabilisation with niobium gives TP347LN good resistance to intergranular corrosion.

The steel may be sensitive to pitting and crevice corrosion even in solutions of relatively low chloride content.


Application

● Cooling tubes in ammonia converters, because of its good resistance to nitrogen absorption and good corrosion resistance.

● With its good hot-strength, and good resistance to hydrogen sulphide and intergranular corrosion, TP347LN is a suitable material for furnace tubes in refineries.

● Furnace tubing used in vinyl chloride production is another example of applications in which this steel is often used.


Seamless Tube Information

Specification: ASTM A-213 / ASME SA-213, ASTM A312 / ASME SA312

Outside Diameter: 6.0-406 mm (1/4’’ – 16’’)

Wall Thickness: 0.5-35 mm (0.0196’’ – 1.378’’)

Length: Max.33000 mm (the maximum length is for the scope of special diameters and walls)

Other sizes are on the request