Q.1) What is the principle of Trickle Varnishing Machine?
Ans.) According to the principle of Impregnation, activated resin is trickled in a thin jet on to the rotating preheated winding. The resin immediately gets heated and its viscosity is reduced. Due to the rotary motion of the winding the resin gets distributed evenly inside the winding without any drain loss. The heated winding accelerates the gelling and curing of the resin.
Q.2) Types of the machines?
Ans.) Basically varnishing machine can be specified in two parts depending on the method of varnishing. One is Trickle Varnishing Machine and other is Vacuum Pressure impregnation plant.
Q.3) Models available in Trickle Varnishing Machine?
Ans.) According to the size of the job to be impregnated and production rate, three models have been established.
Indexing table type varnishing machine
Batch type Horizontal table type varnishing machine
Conveyorised system for varnishing
Q.4) What types of the job can be varnished?
Ans.) Considering all types of the varnishing machine, all winding parts can be varnished such as Stators, Rotors, Coils, Transformer stack windings, small electronics transformers, etc.
Q5.) What are the advantages of this machine?
Ans.) Trickle impregnation process is especially characterized by its low energy cost due to a very short cycle time compared to Dip varnishing or the Vacuum impregnation. Compared to the Dip and bake varnishing method, which uses varnishes containing 50 to 55% solvents and the impregnation cycle of 8 hrs to 24 hrs. Trickle impregnation cycle times are substantially low to the tune of 20 min. to 40 min. Hence it is quite evident that trickle impregnation process offers the most cost economical answer to the impregnation process.
Q.6) Type of Heating Sources?
Ans.) DC power source or Ceramic Infra red heaters.
Oil Filtration Plant :
Q.1) What is working principle?
Ans.) Plants work on heating, filtration and vacuum dehydration & degassing principle.
Q.2) What type of oils can be purified?
Ans.) Both mineral and synthetic insulating oils can be purified. The same can be used for purifying other oils such as hydraulic oil, turbine oil, thermic fluid, cutting oil, etc. with some modifications.
Q.3) Type of plants available?
Ans.) Stationary, Portable mounted on castors, Mobile mounted on trailer plants are available with single and two stage degassing system.
Q.4) Working vacuum of the plant?
Ans.) In case of plants with single stage degassing working vacuum is 3 to 10 torr and in case of plants with two stage degassing system working vacuum is 0.1 to 0.3 torr. Plants with 0.01 torr can be also offered.
Q.5) In how many passes required oil test results will be achieved?
Ans.) In case of single stage plants required oil results will be achieved in three to five passes and in case of two stage plants results will be achieved in one to two passes.
Q.6) Whether transformer oil can be filtered online?
Ans.) Yes, transformer oil can be filtered online but of course at lower load.
Q.7) Advantages of our plants?
Ans.) Low operating cost due to high vacuum filtration with rotary oil sealed pumps, Plants with minimum and easy maintenance, Custom built Plants.