Vacuum Pressure Impregnation
Vacuum Pressure Impregnation
Vacuum Pressure Impregnation (VPI) is a process in which a wound resin-poor winding is completely submerged in a resin. Through a combination of dry and wet vacuum and pressure cycles, the resin is absorbed into the semi-porous insulation to result in a completed winding that is theoretically void free. The VPI process is also used in low voltage machines for winding integrity and heat transfer improvement. M&C uses the VPI process throughout its product and service range, from LV to HV.
M&C use three VPI insulation systems ensuring the correct insulation system for the specific motor and application:
- Thixotropic for low-voltage windings
- Dobeckan for DC windings
- EpoVolt for high & medium voltage AC motors & generator windings
Advantages of using the VPI system are as follows:
- Protection against excessive movement of conductors
- Improved heat transfer from conductor to core and thermal endurance
- Seals insulation against destructive environments
- Provides a composite dielectric structure
- Excellent electrical properties
- Homogeneous void-free insulation system
- Improved thermal conductivity
- Good bond strength
Cost effective and faster processing time than the resin-rich insulation system
