The basic principle of kerosene gas-phase drying equipment is to use kerosene to heat and evaporate under vacuum to become high-temperature kerosene steam, condense when encountering workpieces with lower temperature in the vacuum tank, and release condensation latent heat (about 306.6kj / kg) to heat the body. The condensed kerosene is collected and re transported to the evaporator through the kerosene conveying system for heating and evaporation again. After such cycles for many times, the temperature of the workpiece continues to rise, and the water in it also continues to evaporate into steam, which is pumped away by the vacuum system to achieve the purpose of complete drying.

Process stage of kerosene gas phase drying equipment

① Preparation stage

Put the product in the vacuum tank to vacuum and reduce the pressure to less than 700pa. At the same time, the vacuum tank body is heated and insulated, and the evaporator pre heats the kerosene, so that the kerosene steam outlet temperature of the evaporator gradually rises from 98 ℃ to 130 ℃. The kerosene changes from liquid state to steam state, diffuses in the vacuum tank, and fully exchanges heat with the product.

② Heating stage:

At this time, the vacuum system only needs one maintenance pump to work, and the vacuum degree of the vacuum tank and condensate collection tank is maintained at the vacuum degree specified in the process. The kerosene steam exchanges heat with the transformer, flows to the buffer tank after condensation, and then returns to the evaporator to form a cycle. As the temperature continues to rise, kerosene vapor and water vapor evaporated from insulating materials gradually increase the pressure in the vacuum tank. At this time, the above mixed gas is pumped to the condensation recovery system by the maintenance pump for condensation and separation. The condensed and separated kerosene liquid is then input into the evaporator. The above process continues until the body temperature meets the process requirements, and then it can enter the depressurization stage.

③ Depressurization stage (or low vacuum stage):

Stop transporting kerosene to the evaporator, and continuously draw the mixed gas in the vacuum tank out of the vacuum tank to re evaporate the kerosene remaining in the insulating material for condensation recovery. According to the product capacity and voltage level, the intermediate step-down stage and heating stage can be carried out alternately for several times to achieve the best drying effect.