The pressure relief device PRD is set and fixed on customer request within the standard range from 30 kPa up to 50 kPa, in steps of 5 kPa, with a tolerance of -5/+7 kPa. The fixed setting is stamped on the body of the device.
Pressure relief valve PRD – working principle
The working principle of transformer pressure relief device PRD is very simple. If pressure arises inside a transformer and exceeds a pre-set pressure limit, the pressure safety valve PRD opens its valve clap, which is held by a spring and releases the internal pressure until it declines. After decrease of the pressure, the pressure valve clap moves back to its origin position and closes completely. Normally, the pressure relief device valve PRD will be mounted on top of the transformer. Due to internal faults, it is suggested to have such pressure relief valve to protect the transformer and release arising pressure quite suddenly.
Pressure relief device valve PRD available sizes
- Pressure relief device PRD 1″
- Pressure relief device PRD 1 ½”
- Pressure relief device PRD 2″
Pressure valve properties upon request
- Low temperature for up to -60 °C
- Made of seawater resistant aluminum for offshore applications
- With sealing holes





