Chemoil Advance Technology supplies Change Over Valves from recognized manufacturers for applications requiring controlled switching between two pressure relief or safety devices. These valves are commonly used in systems where one relief valve can be placed in service while the alternate valve is isolated for inspection, maintenance, testing or servicing, subject to the specific configuration and applicable safety requirements.

A changeover valve provides a controlled connection arrangement between the protected process and two relief devices. The design allows the operating relief device to be serviced or replaced while maintaining the required pressure-protection arrangement through the alternate device, when correctly configured and operated.