Installation of the penstocks presented many problems due to the underground conditions particularly the ingress of the water within the vertical shafts.

In order to minimise civil excavation works in the Access gallery and associated tunnels, a system of rotating the penstock sections within their own envelope was developed utilising a turning frame complete with trunnions. A specialised hoisting system was designed to allow the use of a single winch to service both vertical shafts.

Two purpose built welding platforms were fabricated for use within the penstocks with access being gained from the manriding winches.

A further challenge on the project was the installation of the lobsterback sections at the base of the vertical shafts.

Several methods were evaluated using computer graphics with the final system proving very succesful.




To get the project underway some 6,000 tonnes of steel, plant and equipment made the journey of over 2,000 miles by road from Bombay to URI in the foothills of the Himalayas. Delays due to weather conditions and landslides were frequent and it was necesary to anticipate well in advance, the site's requirements for materials and supplies.


Skilled craftsmen were recruited directly by Whessoe in a recruiting campaign across India. Further training was given on site to ensure that high quality fabrication and welding standards were achieved.


As it was not possible to transport pre-fabricated sections to the site location, a fabrication facility was erected on site adjacent to the installation adit on ground built up using tunnel spoil. Foundations were laid and a large fabrication shop was erected.

< URI Hydro-Electric Project in Kashmir for National Hydro Power Corporation/Kvaerner Boving. 5m diameter steel tunnel lining of vertical shafts and high pressure tunnel with associated bifurcation.

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