If the screw chiller shows poor oil return, it is a very troublesome event. Individually, the reason for the poor oil return of the screw chiller is mainly because the gas mixture of lubricating oil and refrigerant appears during the operation process. scene.
Industrial chillers are used in the cooling of plastic processing machinery forming molds, which can greatly improve the surface finish of plastic products, reduce surface marks and internal stress of plastic products, make the products do not shrink or deform, facilitate the demolding of plastic products, and accelerate product shaping, thereby Greatly improve the production efficiency of plastic molding machines.
Specifically, during the operation of the refrigeration system, the mutual miscibility of the refrigerant and the refrigerator lubricating oil will cause the lubricating oil in the refrigeration compressor to operate randomly and the refrigerant will be discharged into the condenser in the form of mist and droplets.
If the performance of the oil separator is not good or the system design is not good, it will cause poor performance and poor oil return of the system.
Of course, the premise is that you don’t have to get fake oil.
What are the effects of poor oil return from screw chillers?
The screw chiller shows poor oil return, which will cause a large amount of lubricating oil to stay in the evaporator pipe. When the oil film increases by 0.1mm, it will directly affect the cooling of the system.
On the other hand, the machine runs short of oil and needs to make up for the lubricating oil all the time.
This will cause the lubricating oil in the system to accumulate more and more, causing vicious reincarnation, increasing the operating cost, and the stability of the landing operation.
In some cases, the circulation of oil and gas mixtures below 1% of the refrigerant gas flow rate is allowed in the system.
How to solve the problem of poor oil return of the screw chiller?
There are two ways to return the oil to the compressor, one is to return the oil from the oil separator, and the other is to return the oil from the air return pipe.
Industrial water chillers are used in the cooling of plastic processing machinery forming molds, which can greatly improve the surface finish of plastic products, reduce surface marks and internal stress of plastic products, make the products do not shrink or deform, facilitate the demolding of plastic products, and accelerate product shaping, thereby Greatly improve the production efficiency of plastic molding machines.
The oil separator is installed on the exhaust pipe of the compressor, and each can separate 50-95% of the oil. The oil return is good, the speed is fast, and the amount of oil entering the system pipeline is greatly reduced, thereby effectively extending the operation without oil return. Time.
It’s not uncommon for cold storage refrigeration systems with extremely long pipelines, full-liquid ice-making systems and freeze-drying equipment with very low temperatures to return oil for ten minutes or even ten minutes after starting up.
A poorly designed system will cause the compressor to stop when the oil pressure is too low.
The high-efficiency oil separator of the refrigeration system can greatly extend the running time of the compressor without oil return, so that the compressor can survive the crisis of no oil return after the machine is turned on. stage.
Refrigeration equipment is used in CNC machine tools, coordinate boring machines, grinders, machining centers, modular machine tools, as well as various types of precision machine tool spindle lubrication and hydraulic system transmission medium cooling.
It can accurately control the oil temperature, effectively reduce the thermal deformation of the machine tool, and improve the machine tool. The machining accuracy.
The lubricating oil that has not been separated will enter the system and flow with the refrigerant in the tube to form an oil cycle.
After the lubricating oil enters the evaporator, on the one hand, due to low temperature and low solubility, a part of the lubricating oil is separated from the refrigerant; on the other hand, the temperature is low and the viscosity is large, and the separated lubricating oil easily adheres to the inner wall of the pipe and flows more difficult.
The lower the evaporation temperature, the harder the oil return. This requires that the design and construction of the evaporation pipeline and the return pipeline must be conducive to oil return.
The common practice is to adopt a drop-type pipeline design and ensure a larger air flow velocity.