Vacuum Impregnation Plants / Pressure Impregnation Plants


Vacuum Impregnation Plants and Pressure Impregnation Plants is designed for varnish impregnation to be carried out in following steps and will be generally as per the schematic diagram attached.

  • Pre-heating the jobs in either Impregnation Chamber or in Oven if you have a less time available.
    Evacuation of Impregnation Chamber (after putting the jobs) to make the voids in the jobs clear and drying of jobs for specific time & required temperature / vacuum.
  • Induction of impregnant (Varnish) in the Impregnation Chamber from impregnant Tank to submerge the jobs in it.
  • Pressurize the Impregnation Chamber with dry air or nitrogen to fill the voids with Impregnant.
  • Return the varnish to Impregnant Tank.
  • Cure the jobs either in Impregnation Chamber or in Oven for specific time if time available is less.
The plant will be generally as per the schematic diagram attached herewith and will mainly consist of following major components:


  • Chamber Dimensions: Diameter – Ø --- mm, Height  ---- mm (suitable for jobs)
  • Material of construction: MS plates, bars, structural etc.
  • Working Pressure: 1- 4 kg / cm2 & Vacuum: 0.1 / 1 / 10 / 50 torr
  • Lid Opening: Screw Davit type for quick opening & closing or hydraulic operated automatic
  • Temperature control: With Thermostat or digital TIC
  • Will be provided with: Oil Heating / cooling Jacket, Quick Clamping bolts, Stirrer, Neoprene Gaskets, Sight glass, Illuminating Lamp, Pressure Safety Valve, Vacuum & Pressure gauges etc. as per the varnish specifications.


Material of Construction: M.S. plates, bars, structurals etc
  • Varnish Tank Capacity: 50 - 80% of Impregnation chamber.
  • Will be provided with: Level Indicator, Motorised Stirrer, TIC to indicate and control the varnish temperature, Return Line Filter to prevent entry of impurities carried away from impregnation chamber to storage tank and suitable drain. Silica Gel Breather will also be provided to prevent absorption of atmospheric moisture.


  • Type: Rotary Oil sealed Vacuum Pump or Roots – Rotary combination.
  • Capacity (free air displacement): 50 LPM to 1600 Mᵌ/hr.
  • Ultimate Vacuum with G. B. Closed - 0.005 torr  to 0.0001 torr.
  • Make: Indowoosung, Everest, Doftel or reputed Make
  • Working Vacuum – 0.1 / 1 / 10 / 50 torr
  • Condenser: Water-cooled. (Water cooling system optional)


  • Type: Piston Type
  • Free air displacement: 10 CFM
  • Working Pressure: 4 Kgf/cm2
  • Make: Reputed make
  • In case of low vacuum/pressure impregnation, combined vacuum/pressure pump can be used


Interconnecting pipes: M.S. ERW, B Class or SS in case of resin impregnation.
  • Valves: Piston Type (Vacuum tight with O'rings & Nylon wipers) OR Ball valves with Teflon seals ( manual or tuated )
  • Connections: Flanged type with Neoprene O'rings.
  • Operating Platform: M.S. Fabricated suitable for easy plant operation in case of big plants.


Centralized Control panel for easy and safe operation will be provided along with necessary gauges and controls.