Our Insulating Oil Filters are designed for the efficient treatment of insulating oil used in transformers, switchgears, substations and switching stations. These filters perform filtration, dehydration and degassification in medium vaccum environment. The plants are available with capacities varying from 255, 600, 1200 and 2400 litres per hour and are available either as semi mobile or fully mobile units.
Our Insulating Oil Filter Plants are designed for continious trouble free operation and are suitable for out door use under all types of climatic conditions.
The fully mobile plant is mounted on wheeled trailer chassis with leaf springs and pneumatic tyres for easy movement on motorable roads. Towing gear is also provided. Three or four screw jacks are provided for proper levelling of the equipment and to take the load of tyres.
Preliminary Magnetic Strainer:
It is a coarse filter. It filters particles upto 40 microns. The strainer can be removed easily for cleaning without dismanting the pipe lines.
A temperature of 70 degree C has to be attained by the dirty ( incoming ) oil to obtain maximum operating effeciency. This is achieved in the heater unit which has heater made with TKKD Nichrome wire. These heaters are thermostatically controlled and are equally distributed into banks usings baffle plates to avoid localised heating of the oil. These heaters have a long life and can be replaced without having to drain the oil.
The filter chamber consists of a number of edge type filter packs which are over compressed using springs. These paper packs are made of specially treated paper discs. The oil being filtered passes from OUT to IN through the minute interstices formed between the filter paper discs leaving all the solid impurities on the outside edge. Cleaning these filter packs is easy and is achieved quickly by passing compressed air through the filter packs in the reverse flow direction. The impurutues are drained through the drain valve.
Dehydration and degassification of the oil takes place in this chamber. Here the insulating oil surface area is incresed and simultaneously vaccum is applied.
This chamber is designed such that the spray of oil is uniform. This ensures maximum exposure of oil to the vaccum. An illuminating sight glass is provided for observing the oil falling clearly.
Inlet and Outlet Pumps:
Vaccum tight trouble free high rated gear pumps are used so as to take care of power fluctuations, varying atmospheric conditions and differing positions of the transformers.
A centralised control cabinet having contactors, over load relays, fuses, indicating lamps, etc., is conveniently located for easy operation of the plant.
The electric motor is of Class 'E' insulation with temperature rise as per IS:325. The motor is suitable for AC power supply of 450 Volts + .10%, 3 Phase, 50 Cycles per second. Plants with single phase AC supply can also be made available.
One pair of 10 metres long hoses with end couplings are supplied with the plant.
Interlocking and Safety Controls:
(1) Interlocking between gear pump and heater elements such taht the heater elements cannot be energised unless gear pump is 'ON'.
(2) Thermometer to switch off heater elements when set temperature is reached by the oil.
(3) Built in relief valve to take care of any accidental pressure rise in outlet side of the gear pump.
(4) An external relief valve in the heater vessel to take care of any abnormal pressure rise in the filter vessels.