Distribution transformer

Instrument/distribution transformers or insulation bushings

Ensuring defect-free transformer insulation is vital and Leybold has the ideal vacuum solutions for it.

Production of instrument/distribution transformers or insulation bushings

Instrument or distribution transformers, as well as insulation bushings are essential components to ensure safe and efficient transfer of electrical power between the high-power networks and external circuits.

Understanding transformer insulations

Transformers contain a lot of insulation material, typically made from paper. They are filled with oil or impregnated by resins. Bushings consist of a sintered ceramic body, combined with a metal core and are typically filled up with insulation oil. From raw material preparation, forming to casting, vacuum technology is deployed for drying and degassing, to remove humidity to prevent electrical breakdown and to remove air bubbles and voids ensuring that the insulation is uniform and free from defects to secure highest reliability. Drying processes under vacuum ensure a low-enough residual humidity level to prevent electrical short-cuts.

Producers often need to follow exact pressure regimes during the cycle to ensure the required product quality. Leybold provides control systems which could exactly follow the requested pressure vs. time profiles.


Pressure vs. time process cycle

Pressure vs. time process cycle

What we recommend

During the vacuum processes, water vapor, particles or resin vapor could enter and condense inside the vacuum system, which needs to be prepared for this. For this reason, more and more users decide to use our dry screw pumps of the VARODRY, DRYVAC or SCREWLINE families combined with Roots blowers of the RUVAC WH and WSU families to ensure trouble-free operation. For lower utilized production lines also our SOGEVAC family of oil-sealed rotary-vane-pumps are a good alternative.

High voltage transformer with electrical insulation bushing

High voltage transformer with electrical insulation bushing

Contact Leybold

Let's talk

We focus on customer proximity. Contact us for all your questions.