Resin-impregnated transformer bushings are connected to oil-insulated power transformers and operate with the following environmental media:

Outdoor (transformer outdoor bushing) Cable junction box-oil (transformer oil bushing) SF6 switchgears (transformer gas bushing) All bushings have a condenser grading and are availble with differenct insulations of the active part: RIP – Resin Impregnated Paper RIS – Resin Impregnated Synthetics RIG – Resin Impregnated Fiberglas

Already in 1960 HSP started the serial production of RIP bushings and has proven the technical benefits of this technology since more than 50 years.

Trench and HSP dry type bushings are known all around the world for their reliable product design and quality. To support the market trend to RIP and RIS bushings, HSP and Trench have largely extended their production capacities in the recent years and reworked their internal processes. The target is to ensure a high delivery performance with very competitve lead times. This makes the Trench & HSP Group a preferred partner for Transformer OEMs, Transformer service providers and of course end customers worldwide.

IP TRANS­FORMER BUSH­INGS RIP transformer bushings are oil-free transformer bushings with a solid active part made of resin-impregnated paper and a condenser control. The air side housing is available in a porcelain version or as a silicone composite material. This bushing with dry filling is designed for rated voltages of up to 1200 kV and rated currents up to 6000 A.

RIS TRANS­FORMER BUSH­INGS RIS transformer bushings from HSP are oil-free and at the same time paper-free transformer bushing with a solid active part made of resin-impregnated synthetic and a condenser control. The air side housing is a silicone composite insulator. This bushing with dry filling is designed for rated voltages of 24 to 245 kV and rated currents up to 2000 A.

A particular advantage is higher resistance against humidity. Among other things this allows easier storage.

For more information please visit the HSP Homepage.

RIG TRANS­FORMER BUSH­INGS Typical applications for High Current RIG transformer bushings are step-up transformers (GSU).

Trench High Current bushings CFPT are available from 24 kV to 36 kV with a current rating up to 31.500 A according to IEC 60137.

The performing technology of Resin Impregnated Fiberglas provides high temperature withstand (Class F insulation 155 °C). There is no current limitation when the bushing is operated under temperature up to 70 °C in a bus-duct and transformer oil temperature of 90 °C.

The design of the High Current bushing facilitates the interchangeability with the existing units. They are available with porcelain or composite insulator on air side with the same dimensions.