Steel Ring
A steel ring or flange back ring is a steel ring that is placed behind a flange to ensure a proper connection and seal between the flange and the pipe or fitting.Uses of steel rings
These types of rings are very common in polyethylene (HDPE) or PVC pipes, because these pipes themselves do not have the strength of the metal to withstand the pressure of the flange bolts. Therefore, the ring behind the metal flange is used to evenly distribute the mechanical forces of the bolts.
It is usually used to connect polymer pipes to cast iron valves and fittings. Also, in places where there are no facilities for welding polyethylene pipes, the pipes are equipped with rings and flanges before installation and are easily installed on site.
Ring and flange components
Usually, during installation, a gasket or lytic washer is placed between the flanges and the assembly is connected and secured with appropriate bolts and nuts.
Ring material
Usually made of steel, which in special cases is made resistant to environmental conditions by hot-dip galvanizing.
| DN | Pipe Outside (mm) | Code | D (mm) | K (mm) | d2 mm) | Bolting | |
| Number | Size | ||||||
| 20 | 25 | R15S02 | 105 | 75 | 14 | 4 | M12 |
| 25 | 32 | R15503 | 115 | 85 | 14 | 4 | M12 |
| 32 | 40 | R15504 | 140 | 100 | 18 | 4 | M16 |
| 40 | 50 | R15505 | 150 | 110 | 18 | 4 | M16 |
| 50 | 63 | R15S06 | 165 | 125 | 18 | 4 | M16 |
| 65 | 75 | R15507 | 185 | 145 | 18 | 8 | M16 |
| 80 | 90 | R15508 | 200 | 160 | 18 | 8 | M16 |
| 100 | 110 | R15509 | 220 | 180 | 18 | 8 | M16 |
| 100 | 125 | RI5510 | 220 | 180 | 18 | 8 | M16 |
| 125 | 140 | RI5S11 | 250 | 210 | 18 | 8 | M16 |
| 150 | 160 | RI5S12 | 285 | 240 | 22 | 8 | M20 |
| 150 | 180 | R15S13 | 285 | 240 | 22 | 8 | M20 |
| 200 | 200 | RI5S14 | 340 | 295 | 22 | 12 | M20 |
| 200 | 225 | RI5S15 | 340 | 295 | 22 | 12 | M20 |
| 250 | 250 | RI5S16 | 405 | 355 | 26 | 12 | M24 |
| 250 | 280 | RI5S17 | 405 | 355 | 26 | 12 | M24 |
| 300 | 315 | RI5S18 | 460 | 410 | 26 | 12 | M24 |
| 350 | 355 | RI5S19 | 520 | 470 | 26 | 16 | M24 |
| 400 | 400 | R15520 | 580 | 525 | 30 | 16 | M27 |
| 450 | 450 | RI5S21 | 640 | 585 | 30 | 20 | M27 |
| 500 | 500 | R15S22 | 715 | 650 | 33 | 20 | M30 |
| 600 | 630 | RI5S24 | 840 | 770 | 36 | 20 | M33 |
Note: Thickness according to customer order
