Christian Maier’s standard series H and HW rotary joints, available from Novasys Group , have a maximum nominal diameter of 100mm and are designed for transferring water, steam and thermal oil. The HWA, HWB and HWX series of rotary joints are designed for extreme conditions including higher speeds, higher loads and larger diameters.
A modular system of housing flanges and gasket connections enable several connection possibilities, and can be modified to a different combination later. Christian Maier’s standard series H and HW rotary joints’ housings are made of ductile cast iron with the cover and rotor made of chrome steel. The rotors are of 65mm and are above steel featuring sealing face chrome steel. The high temperature-resistant spring is made of stainless steel.
Christian Maier’s standard series H and HW rotary joints feature a sealing ring of compression-loaded wear-resistant graphite carbon. Due to their design, the H and HW rotary joints are shatter-proof under high pressure. The HW series of rotary joints is fitted with metal-impregnated graphite carbon, and is suitable for thermal oil and for higher pressures, temperatures and speeds. The bearing is secured against rotation, and a slide bushing is used as a gap seal for the rotating inner pipe. There is a wear indicator for the sealing ring at the rotor.
Christian Maier’s standard series H and HW rotary joints are easy to repair, maintenance-free and no re-lubrication is required. Connection to rotating pressurised system is by means of:
- Standardised connecting piece with right-hand or left-hand male thread BSP (ISO 228)
- Sealing and centring cone at the end of thread
- Adapter pieces for NPT and other threads are available
- K flange with conical inner ring or quick disconnect
Radial and axial housing connections are available with right hand thread BSP (ISO 228). Adapter pieces are available for NPT and other threads along with flange connections.
According to DIN 4757 safety regulations, sealing in the thread is not allowed when using thermal oil. Christian Maier use flange connections, and the screw thread for fixed inner pipe is always right-handed, even when thread on rotor is left-handed.
Rotation of the housing is prevented by means of an anti-rotation fork on the rotary joint cover, where the locking bolt engages. Christian Maier rotary joints are designed such that the thermal expansion of the roller and wear of the seals and bearing cause an axial displacement of the housing (away from the roller). If this does not occur, the rotary joint does not operate or seal properly.
The HWA, HWB and HWX series of rotary joints have the following features:
- Housings of ductile cast iron. The HWA series of rotary joints is of 100mm and above. It is made of steel in a welded design
- Rotors manufactured of stainless steel 1.4571 (316) or carbide coated carbon steel. All other steel parts in stainless steel
- Metal-impregnated sealing ring is suitable for high pressure
- Housing bearing secured against rotation
- Connection to the rotating pressurised system is by means of a K-flange and conical inner ring (quick disconnect)
Radial and axial housing connections are with right-hand thread to ISO 228. As an option, 32 to 100mm with screw flange and gasket PN 40 DIN 2656, nominal diameter 100 to 300mm with welded flanges PN 40 DIN 2635. For nominal diameter DN 15 to 25mm, metal hoses sealed with a gasket are supplied, as housing flanges would be heavy.According to DIN 4757 safety regulations, sealing in the thread is not allowed when using thermal oil. Rotation of the housing is prevented by means of an anti-rotating fork at the housing, where the locking bolt engages. From nominal diameter of 100mm, the unit weight is partially supported by means of the housing lug.