Double sphere rubber expansion joint is also called double ball rubber joint, double bellow expansion joint, double sphere flexible connection, twin sphere rubber expansion joint etc. It has two spheres, comparing with single sphere rubber expansion joint, it have bigger installation length, bigger compensation capacity.
Double sphere rubber expansion joint is also consisted of flange, pressurized ring, key frame, inner and outer rubber layer. Rubber material is usually EPDM, flange material is usually carbon steel galvanized, flange standard is usually ANSI 150LB, JIS 10K, DIN PN16 etc. The working pressure is usually PN16, nominal size is usually since from DN25 to DN3000. Working temperature is usually -15~+80 celsius degree. Biggest characteristic is still reduce the vibration and noise of pipeline, protect the pipes and prelong the service life of pipe!
| Size | Pressure | D | D1 | n*d | b | L |
| DN32 | PN16 | 140mm | 100mm | 4*18mm | 14mm | 165mm |
| DN40 | PN16 | 150mm | 110mm | 4*18mm | 16mm | 165mm |
| DN50 | PN16 | 165mm | 125mm | 4*18mm | 18mm | 165mm |
| DN65 | PN16 | 185nm | 145nm | 4*18mm | 18mm | 170mm |
| DN80 | PN16 | 200mm | 160mm | 8*18mm | 20mm | 175mm |
| DN100 | PN16 | 220mm | 180mm | 8*18mm | 20mm | 225mm |
| DN125 | PN16 | 249mm | 210mm | 8*18mm | 21mm | 225mm |
| DN150 | PN16 | 285mm | 240mn | 8*22mm | 22mm | 225mm |
| DN200 | PN16 | 340mm | 295mm | 12*22mm | 24mm | 325mm |
| DN250 | PN16 | 405mn | 355mm | 12*26mm | 26mm | 325mm |
| DN300 | PN16 | 460mm | 410mm | 12*26mm | 26nm | 325mm |
| DN350 | PN16 | 520nm | 470mm | 16*26mm | 28mm | 350mm |
| DN400 | PN16 | 580mm | 525mm | 16*30mm | 30mm | 350mm |
| DN450 | PN16 | 640mm | 585mm | 20*30mm | 32mm | 350mm |
| DN500 | PN16 | 712mm | 650mm | 20*33mm | 36mm | 350mm |
| DN600 | PN16 | 840mm | 770mm | 20*36mm | 40mm | 400mm |
| Working pressure | PN16 |
| Test pressure | PN24 |
| Explosion pressure | PN48 |
| Applicable temperature | -15~+120 celsius degree |
| Applicable media | Air, compressed air, water, sea water, hot water, oil, acid and alkali etc. |
