Welding Neck Flange WN ASTM A182 Gr. F51 8" SCH 40S, 600# NACE MR0175/ ISO 15156

A182 F51 is the grade of duplex stainless steel forgings

The corresponding pipe and plate grades are S31803. In the standards of pipe SA312 and plate SA240, the hardness of S31803 is less than HB293. The so-called duplex stainless steel refers to the ferrite phase and austenite phase in their solid solution structure account for about half, generally less The content of dual-phase steel also needs to reach 30%.

In the case of low C content, the Cr content is 18%~28% and the Ni content is 3%~10%. Some steels also contain alloying elements such as Mo, Cu, Nb, Ti, and N.

This type of steel has the characteristics of austenitic and ferritic stainless steel. Compared with ferrite, it has higher plasticity and toughness, no room temperature brittleness, and has significantly improved intergranular corrosion resistance and welding performance, while maintaining iron. The 475°C brittleness and high thermal conductivity of plain stainless steel are characterized by superplasticity.

Compared with austenitic stainless steel, the strength is high and the resistance to intergranular side food and chloride stress corrosion is significantly improved. Duplex stainless steel has excellent pitting corrosion resistance and is also a nickel-saving stainless steel. It is mainly used in the production of acid oil and gas wells.

Products range:

Difference between butt welding flange with neck and flat welding flange with neck

First, the welding form is different: the welding form of the flanged pipe with a neck is a fillet weld, and the welding weld form of the necked butt welding flange and the pipe is a circular weld;

1: Different materials: The flange material with neck flat welding is processed with thick ordinary steel plates as required, while the flange material with neck butt welding is mainly made of forged steel parts.

2: The nominal pressure is different: the nominal pressure of the neck-welded flange is 0.6 ~ 4.0MPa, and the nominal pressure of the neck-welded flange is 1 ~ 25MPa.

Second, the welds with neck butt welding flanges and pipes belong to category B welds, and the welds with neck flat weld flanges and pipe joints belong to category C welds, and the nondestructive testing after welding is different.
3: The neck flat welding flange and the neck butt welding flange cannot be replaced at will. In terms of manufacturing angle, the neck flat welding flange (SLIPON for short) is large, small in weight, and low in cost. In addition, butt welded flanges with a nominal diameter greater than 250 mm (WN is short for WELDINGNECK) should also be tested at low cost.