ASTM A182 F11, F22, F304, F316 (Alloy and Stainless Flange) Specification
ASTM A182 standard specification is for forged and rolled alloy and stainless steel pipe flanges, fittings, valves and parts for high temperature service.
Common grades of alloy steel is Grade F5, F9, F11, F22, stainless steel F304/L and F316/L.
Standard Scope
The standard applies to forged low alloy steel and stainless steel pipe parts for use in pressure systems. These include flanges, fittings, valves and similar parts that meet specified size or size standards.
It includes several grades of low carbon alloy steel and ferritic, martensitic, austenitic and ferritic-austenitic stainless steels. Selection should be based on design and application requirements.
When additional tests or inspections are required, supplementary requirements may be specified by the purchaser in the order.
Common Grades
| Category | Grades |
|---|---|
| Alloy Grade | ASTM A182 F5, F9, F91, F92, F11, F12, F21, F22 |
| Stainless Steel Grade | ASTM A182 F304, F304L, F316, F316L |
Alloy Flange: ASTM A182 F11, F22 — the most commonly used alloy steel grades.
Stainless Steel Flange: ASTM A182 F316 — widely used for weld neck, slip-on, blind, and socket weld flanges.
Available sizes up to 48 inch OD with pressure classes from 150# to 2500#.
Units
This specification is expressed in inch-pounds and SI units.
Manufacture Types
For Low Alloy Ferritic Steels
- Open hearth furnaces
- Electric furnaces
- Basic oxygen process (with optional degassing and refining)
For Stainless Steel
- Electric furnace (with optional refining)
- Vacuum furnace
- Remelting processes such as vacuum or electroslag remelting
Discard material shall be removed sufficiently to eliminate shrinkage defects and segregation.
Chemical Composition
Chemical heat analysis shall be performed in accordance with the required composition limits.
Grades containing lead, selenium, or other machinability-enhancing elements shall not be used.
Elements exceeding specified limits for the corresponding grade are not permitted.
Except for nitrogen in stainless steel, unspecified elements shall not be present in amounts that meet the requirements of another grade.

