NSH VFD (Oil Purifier, Oil Purification, Oil Filter, Oil Filtering) series is mainly used to improve the properties of insulation oil. It can remove water, gas, particulate matters etc. from the insulating oil effectively and rapidly so as to boost performance of transformers, circuit breakers, mutual inductors, cable and capacitors which has insulation system. VFD oil filter (oil purifier, oil purifying) series is specialized in purifying branded oil, insulating oil of high voltage and super high voltage transformer. Additionally, it is suitable for treating low viscosity lubrication oil. Model VFD oil recycling series utilizes coacervation technology, coalescing technology, separating technology and refined purification technology.