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SERD Solved Customers Problem

Our customer had to replace Bushings at a 36kV-Transformer. These Bushings of resin bonded paper type have been aging during more than 25 years. Leaking irreparably, they could no longer be qualified as safe and were irreparable untight.
The primary outlet conductor of the Transformer with the Bushing head piece was fixed and connected by hard-soldering.
In case of exchange these Bushings first the state of insulating oil must be slightly reduced below the transformer cover, however still the windings must remain oil immersed.
In spite of all precautions while re-soldering the conductors, there is a certain risk implicit,that the conductors do not correctly fit to the new Bushing. In this case the repair action gets very time consuming and cost-intensive. Besides, the on-site soldering bears the considerable risk of damag at the Transformer, especially in the case that parts fall into the vessel.

Standard Bushings for an exchange without the risky re-soldering were not available.

SERD solved the problem. A modern Bushing with silicon insulator of type SERD STC was the problem oriented solution. This Bushing can be used for exchanges of old units without the need of a modification of the conductor fixation.  After reassembling the defect Bushings, the conductor can be attached directly to the new SERD-Bushing. Our customer was fully convinced of the save solution of a risk-freen exchange. The slightly higher cost for the new Bushing is easily compensated by the considerably decreased cost of the exchange operation.
This is only one example of the typical customer orientation and the flexibility of SERD!

Left:
The old Bushing  with Porcelain insulator, to be replaced.

Right:
New SERD Bushing Type STC with silicon-insulator.

The exchange proved, that the conductor fits perfectly ensuring an unproblematic installation. As a result the connection with the Transfoer remainded unchanged.