STOP/SYSTEM™ for higher pressures
Stop system is manufactured in pressure series PN 5, PN 12 and PN 24 bar as standard and equipment for pressure series PN 40 and PN 80 has been prepared.
For STOP/SYSTEM™ employment for smaller dimensions and lower pressure series, manual control is used, for higher pressure series (from PN 24) hydraulic control is necessary. Also drilling equipment for higher pressure series has already hydraulic drive.
Weld on sleeves for pressure series up to PN 24 are available as weld on sockets, for higher pressure series, split sleeves are used because of security reasons.
When working on a high-pressure system, it is often possible to reduce operating pressure to lower values: e.g. from PN 25 bar → PN 5 bar or from PN 40 → PN 5 bar and carry out maintenance work using a device with operating pressure PN 5 bar, but steel adapting piece tested for PN 25 bar or double sleeve tested for PN 40 bar must be used. After completion of the work, the pressure is again increased on PN 25 or PN 40. Similarly, it can be done with higher pressures, e.g. PN 80 is lowered to PN 25.