ASTM A193 B7M Slip-On Flanges
The ASTM A193 B7M Slip-On Flange (SOF) is a common pipe forging component characterized by a bore slightly larger than the outside diameter of the pipe. This design allows the flange to easily slip over the pipe before welding, facilitating simple alignment and assembly. Unlike weld neck flanges, the SOF is secured by two fillet welds—one on the inside and one on the outside—providing adequate strength but typically used in lower-pressure applications than Weld Neck Flanges. Zeron Fasteners manufactures these flanges using the B7M equivalent alloy steel grade. The critical feature is the material's controlled maximum hardness (the 'M' designation), which is vital for providing enhanced resistance to chloride stress corrosion cracking (SCC). This makes the B7M Slip-On Flange suitable for high-temperature service in the petrochemical, chemical, and power generation industries where SCC resistance and compliance with sour service standards (like NACE MR0175) are mandatory.
Related Products
ASTM A193 B7M Slip-On Flanges Chemical Composition
| Element | Composition (% by Mass) |
|---|---|
| Carbon (C) | 0.38 - 0.48 |
| Manganese (Mn) | 0.75 - 1.00 |
| Phosphorus (P) | ≤ 0.035 |
| Sulfur (S) | ≤ 0.040 |
| Silicon (Si) | 0.15 - 0.35 |
| Chromium (Cr) | 0.80 - 1.10 |
| Molybdenum (Mo) | 0.15 - 0.25 |
ASTM A193 B7M Slip-On Flanges Mechanical Properties
| Property | Minimum Requirement (Equivalent Grade B7M) |
|---|---|
| Tensile Strength, min | 100 ksi (690 MPa) |
| Yield Strength, min | 80 ksi (550 MPa) |
| Elongation in 2 in. (50 mm), min | 16% |
| Reduction of Area, min | 50% |
| Hardness, max (Brinell) | 235 HBW |
| Hardness, max (Rockwell) | 22 HRC |