Pneumatic control developer Midland-ACS has come up with a dual-function device which it claimed could save equipment from damage in the event of a pressure regulator failure.
Called OPD Stemsaver, it combines a pressure regulator with an over-pressure device, and is designed to prevent the full air line pressure hitting downstream devices should the regulator fail - many pneumatic devices can be badly damaged by excessive pressure, said Derek Clure, the company's UK sales manager. He cited the example of an incident two years ago on a North Sea oil rig, where an actuator's cover blew off, causing thousands of pounds-worth of damage and downtime.
OPD Stemsaver was developed by Midland-ACS, which is part of ITT Flow Control, in response to a request from that North Sea oil producer. Clure said that the producer has so far deployed 93 of the units, and plans to fit more.
He added that in pneumatic control systems, the pressure regulator is typically a key potential failure point. He said that if Stemsaver's primary regulator fails, the secondary device - which uses a different technology and is set for a slightly higher pressure - activates either to limit downstream pressure or release it to the atmosphere.
He said that the device's advantages over fitting a second regulator included a predictable shut-down to enable repairs to be done, plus its ability to alert operations management to the problem.