Introduction
Class B is a grey cast iron grade covered by ASTM A126. Typical family applications include pump bodies, valve bodies and covers.
| Field | Value |
|---|---|
| Designation | Class B |
| Material Type | Cast Iron |
| Sub Type | Grey Cast Iron |
| Product Form | casting |
Manufacturing Process
Sand Casting
Shell Molding Casting
Lost Foam Casting
Equivalent Materials
N/A
Similar Materials
N/A
Reference Standards
| Standard | Standard Title | Edition | Specification | Identifier |
|---|---|---|---|---|
| ASTM A126 | Standard Specification for Gray Iron Castings for Valves, Flanges, and Pipe Fittings | 04 | Class B | — |
Related Casting Products
Physical Properties
N/A
Chemical Composition
| Element | ASTM A126Edition 04 |
|---|---|
| P | ≤ 0.75 % |
| S | ≤ 0.15 % |
Heat Treatment
ASTM A126–04
N/A
Mechanical Properties
Core Mechanical Properties
ASTM A126 — 04 · Table 1 — Normative
| Property | base requirements |
|---|---|
| Tensile Strength | ≥ 31 ksi |
Notes
- one tension test per lot; A126 test bar unless §13.1 alternative
Welding Conditions
N/A
Applications
Grey cast iron ASTM A126 Class B is typically used for valve pressure-retaining parts, pipe fittings, and flanges. Other cast components used in this material family include pump bodies, valve bodies and covers. Typical settings include water, heating and industrial piping systems. Finished-component pressure, temperature and fluid limits remain separate from the material grade and its standard-specific restrictions.
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Email Us for a QuoteLast Updated: November 6, 2026