Butt Welded Lap Stainless Steel Pipe Fittings , JIS B2312 / ANSI B16.9 Steel Flanged Fittings
Fittings and Flange Butt Welded Lap Joint Stub End Stainless Steel Pipe Fitting JIS B2312 / ANSI B16.9
Stub Ends are fittings used in place of welded flanges where rotating back up flanges are desired. They are also called Lap Joints and Vanstone Flared Laps. A rotating back up flange seats itself against the back surface of the Stub End. When bolts are added, the clamping action of the bolts presses the rotating back up flange against the back of the Stub End. The gasket surface of the Stub End then presses against a gasket and another gasket surface providing joints like standard flange joints. The seal is made by the gasket surface of the stub end alone, the flange only provides the clamping pressure on the joint.
Drawing:
Standard: ASME B16.9,MSS SP-43 1/2
Nominal Pipe Size |
Outside Diameter at Bevel |
Length |
Radius of Fillet |
Lap | |
| A | B | ||||
| NPS | D | L | R | G | |
| 1/2 | 21.3 | 51 | 3 | 0.8 | 35 |
| 3/4 | 26.7 | 51 | 3 | 0.8 | 43 |
| 1 | 33.4 | 51 | 3 | 0.8 | 51 |
| 11/4 | 42.2 | 51 | 5 | 0.8 | 64 |
| 11/2 | 48.3 | 51 | 6 | 0.8 | 73 |
| 2 | 60.3 | 64 | 8 | 0.8 | 92 |
| 21/2 | 73 | 64 | 8 | 0.8 | 106 |
| 3 | 88.9 | 64 | 10 | 0.8 | 127 |
| 31/2 | 101.6 | 76 | 10 | 0.8 | 140 |
| 4 | 114.3 | 76 | 11 | 0.8 | 157 |
| 5 | 141.3 | 76 | 11 | 1.6 | 185 |
| 6 | 168.3 | 89 | 13 | 1.6 | 218 |
| 8 | 219.1 | 102 | 13 | 1.6 | 270 |
| 10 | 273 | 127 | 13 | 1.6 | 324 |
| 12 | 323.8 | 152 | 13 | 1.6 | 381 |
| 14 | 355.6 | 152 | 13 | 1.6 | 413 |
| 16 | 406.4 | 152 | 13 | 1.6 | 470 |
| 18 | 457 | 152 | 13 | 1.6 | 533 |
| 20 | 508 | 152 | 13 | 1.6 | 584 |
| 22 | 559 | 152 | 13 | / | 641 |
| 24 | 610 | 152 | 13 | 1.6 | 692 |
Note:
Minimum lap thickness shall not be less than nominal wall thickness.
Contact faces of stub ends shall have a concentric serration or spiral according to the purchaser’s requirements.
These lengths and radius apply for schedule 40s or thinner stainless steeel pipes.
Radius of fillet B is only effective to MSS SP-43 lap joint stub ends.
Application: Petroleum, chemical, machinery, electric power, shipbuilding, papermaking, construction etc.
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.

