Pressure relief valves "T" type are used to evacuate any overpressure found in the oil tanks. They operate in case the pressure increases in an accidental and uncontrolled way creating the danger of explosion of the same tanks. Their main characteristic is to operate in a very short period of time (few thousandths of a second) by evacuating the pressure increase that has taken place. These valves are widely used in the metal tanks of oil-cooled electric transformers. In fact a sudden and violent short-circuit generates instantaneously an enormous volume of gas which, if not readily discharged towards the exterior, could cause the explosion of the transformer itself. The application of one or more valves and the choice of the proper diameter must be made by taking into consideration the oil volume contained in the transformer. Please contact our Sales Department in case you need further information and/or catalogues.
Types
Valve "T" type with protection cover and electric switch for applications in power transformers. They are manufactured in four sizes: 50-80-125-200 mm (oil volume diameter).
Valve "VG" type without electric switch for applications in distribution transformers. They are manufactured in two sizes 25-50 mm (oil volume diameter).
New duct for safety devices
The protection of the environment is one of the main aim which has to be pursued by any industry. In order to do this Comem has developed a new duct for safety devices type"T", i.e. 50, 80 and 125, which allows to collect the oil drained from the valve following to an internal overpressure of the transformer. The perfect hydraulic tightness of the system guarantees that not any drop of oil is dispersed in the environment, but carried through a pipe (on demand) and then collected in a tank (not supplied). The oil duct is made in stainless steel plate not painted and it is solely supplied along with the safety device. Detailed assembling instructions are supplied with the equipment. See the video of the working test attached.
New safety valve type M
Always environmental focused, Comem extended the range of pressure relief devices with the new valve type M. This valve is equipped with a new cover with duct that guarantees a better collection of drained oil and a greater protection of electrical switches. Get in touch with our Sales Dept. to have further information
