Description
PVC Backing Rings
Description
PVC backing rings are used to convert stub flanges to a full-face flange and are able to rotate independently of the stub.
Care should be taken when selecting PVC stub flanges and backing rings from different suppliers as many manufacturers custom make their own rings.
Flange Sizing
The number and diameter of holes together with the PCD determines the backing ring size and pattern. The PCD (Pitch Circle Diameter) is the measurement from the centre of one bolt hole, across the centre of the backing ring, to the centre of the opposite hole.
The table below details the specification for both imperial and metric PN10/16. We can also supply Table D/E if required.
|
Ring Size |
o.d. mm |
PCD mm |
Bolt Holes |
Bolt Hole Dia mm |
Bolt Dia mm |
| 1/2" / 20mm | 95 | 65 | 4 | 14 | M12 |
| 3/4" / 25mm | 105 | 75 | 4 | 14 | M12 |
| 1" / 32mm | 115 | 85 | 4 | 14 | M12 |
| 1 1/4" / 40mm | 140 | 100 | 4 | 18 | M16 |
| 1 1/2" / 50mm | 150 | 110 | 4 | 18 | M16 |
| 2" / 63mm | 165 | 125 | 4 | 18 | M16 |
| 2 1/2" / 75mm | 185 | 145 | 4 | 18 | M16 |
| 3" / 90mm | 200 | 160 | 8 | 18 | M16 |
| 4" / 110mm | 220 | 180 | 8 | 18 | M16 |
| 6" / 160mm | 285 | 240 | 8 | 22 | M20 |
| 8" / 200mm | 340 | 295 | 12 | 22 | M20 |
| 10" / 250mm | 395 | 355 | 12 | 26 | M24 |