Impregnation installation


The main components of an impregnation installation are:

  • One or more tanks to stock resins or varnishes before and after impregnation
  • A horizontal or vertical autoclave in which impregnation will be carried out. A de-pressurisation phase is always used to allow the varnish to penetrate the part without trapping air bubbles. The latter usually allows the varnish to be transferred by pressure difference with the tank. Depending on the models, a pressurisation phase can also be provided to allow the varnish or resin to better penetrate all the gaps or porous materials
  • A vacuum pump to create the vacuum in the autoclave and/or tank
  • Possible pipes and/or pumps to manage the transfers of resin during the different phases
  • A filter to purify the resin or varnish on its return to the storage tank


Our product line is based on two families:

  • Sans-titre-2Single block products on which the autoclave is located just over the tank. This type of impregnation is especially adapted to small capacities. It is remarkably compact (a tank/autoclave unit plus a separate vacuum pump) and very easy to operate since the transfer from the tank to the autoclave occurs via the pressure difference generated by the vacuum pump, and the discharge to the tank uses gravity because the tank is under the autoclave
  • Sans-titre-3Products with separate tanks more suited to large installations. Depending on the configurations (possibility of locating the tank and the autoclave) varnish transfers can be achieved by pressure difference (vacuum applied inside the autoclave on the way in and in the tank on the return), using a pump, or even using gravity.

These two product families can carry out impregnation in a vacuum only, or in a vacuum and then under pressure. The latter process, which is fully automated, has many advantages:

  • Better resin penetration into all the gaps and into the heart of porous materials
  • A wider choice of high viscosity resin and varnish (solvent-free or single-component product)
  • Better heat exchange in the conductors
  • Significant reduction in local hot spots
  • More compact insulation

The vacuum/pressure line can be proposed in a standard model from 0.5 mbars to 7 bars (beyond these values please contact us)

These products can be customised to your requirements using a wide range of options such as (list not exhaustive):

  • Vertical or horizontal autoclave
  • Doors on hinges or an arm with manual or automatic opening
  • Storage tank under vacuum
  • Handling system for products to be impregnated (including a trolley for large diameter horizontal autoclaves installed in a pit)
  • Warming or cooling (using a cooling unit) of the tank with a double heat insulated wall to keep the varnish at a constant temperature
  • Heat exchanger to bring the resin to temperature when transferring it to the autoclave.
  • Mixer/beater on the tank to mix the varnish and keep its composition consistent (twin-component) and at the correct temperature (recommended option combined with the tank heating or cooling options). Special manufacture for vacuum tanks
  • Autoclave heating with a double heat insulated wall and a thermal oil warmer
  • Increased filtering (200µm) of the varnish transfer line to the autoclave in addition to the strainer fitted on all models on the varnish return line to the tank
  • Condenser before a vacuum pump with a cooling unit to protect the pump from varnish vapours when necessary (vacuum distillation phenomenon possible with certain varnishes that have a low vapour pressure)
  • Stronger vacuum using a multi-stage pump system, …

Thanks to our experience of impregnation we can develop all types of derived or complementary installations to meet your needs:

  • Impregnation of motors, alternators, transformers, magnetic circuits, fuses, electronic components, …
  • Impregnation of porous materials (wood, polyurethane foams, metal alloys, …)
  • Impregnation using varnishes, resins, mineral oils, silicone-based products, water based mixtures, liquid carbons, etc. (on condition that they have a compatible vapour pressure curve)
  • Drying of parts upstream (atmospheric or vacuum)
  • Downstream centrifuging
  • Upstream/downstream weighing to find out the quantity of absorbed resin
  • Measurement of impregnation product density
  • Automatic end of cycle cleaning and multi impregnation product management