Material Grade Reference

ASTM A234 WPB

Carbon steel butt-weld fittings. A234 WPB is the default carbon steel grade for butt-weld fittings — elbows, tees, reducers, caps — in general process, utility and structural piping. It is by a wide margin the most-ordered fitting grade worldwide, which is why it is the one most often held in stock rather than made to order.

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Cross-system equivalents

Cross-system grades are nearest counterparts, not drop-in substitutes. Chemistry and mechanical envelopes overlap but are not identical — where a design code names a grade, order that grade. Final selection should be confirmed by your project engineer against the governing code.

Standard systemGrade designation
ASME / ASTMA234 WPB
EN / DINP235GH (1.0345)
JISSTPT370 / PT370
GOSTСт20
GB20#

Where this grade belongs

Where it does not

The failures we see most often are not bad material — they are the right material in the wrong service.

What we supply in ASTM A234 WPB

Forms: Elbows (45° / 90° / 180°, LR & SR), equal and reducing tees, crosses, concentric and eccentric reducers, caps

Size range: DN15 – DN1200 (1/2" – 48"), Sch 10 through Sch 160 / XXS

Documentation available

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Frequently asked

What is the EN equivalent of A234 WPB?

P235GH (material number 1.0345) is the counterpart most commonly referenced. The two overlap in chemistry and strength but are governed by different standards — where your design code names one, order that one.

Is A234 WPB suitable for low temperature?

Not as standard. A234 WPB has no impact-test requirement. For service below roughly −29 °C, A420 WPL6 is the low-temperature counterpart, impact tested at −46 °C.

What pipe and flange grades pair with A234 WPB?

A106 Gr.B or A53 Gr.B pipe and A105 forged flanges are the conventional matching grades in an all-carbon-steel line.

Related grades

Full cross-reference across all families: Technical Guide § 2 — Material Grade Equivalents. Pressure class and schedule conversion: § 3 — Pressure Ratings & Pipe Schedules.