Pressure testing and pressure equalising across valves demands a high
level of control. This has been achieved by WOMA (GB) with the development
of a range of Pressure Test Units.
The unit features a variable displacement swish plate hydraulic pump
connected to a suitably sized Zone 1electric motor. The high pressure
pump is in turn driven by a hydraulic motor. Speed control and thus
flow control is achieved by varying the swash angle on the hydraulic
pump.
In order to fill the vessel the hydraulic pump is brought up to 'maximum
swash' which in turn operates the high pressure pump and full speed
and flow. Pressure and flow can be monitored by integral flow and
pressure gauges. As the target pressure is neared the swash angle
can be reduced and therefore the rate of fill and pressure rise reduced.
Once the target pressure is reached the swash is fully backed off
and the flow to the vessel stops. An integral check valve maintains
the desired system pressure.
WOMA 8
East Portway, Portway Industrial Estate, Andover, Hampshire,
SP10 3LU, UK
