NSH Vacuum Insulating Oil Purifier, use for purification and treatment of insulating oils, oil filling and drying of electrical equipment, such as transformers. This series is able to purify trace water, gas and particulate matters effectively. It is divided into three models for different practical usage: â?¢VF: Single-stage Vacuum Transformer Oil Purifier â?¢VFD: Double-stage Vacuum Transformer Oil Purifier â?¢VFD-R: Double-stage Vacuum oil Purification and Regeneration Plant VFD-A: Advanced Full-automatic Vacuum Insulation Oil Purifier Tailored: Tailored Vacuum Oil Solutions