Improved tensioners for wind turbine foundation bolting

Paul Boughton

Leading bolt tensioner manufacturer Boltight Ltd is meeting the increased demand for specially designed bolt tensioners for use in the expanding global wind energy market.

Specially designed tools are required to tighten wind turbine base and foundation bolts because the bolts are located very close to the tower structure. There is little room onsite to operate bulky tools and engineers have to get on with the job quickly in often difficult weather conditions.

Boltight's Foundation Bolt tensioners offer a compact solution that is easy-to-use, durable, reliable and low maintenance. The company designed the tools using Finite Element Analysis and 3D solid modeling and carried out extensive field testing to ensure the tensioners are easy-to-operate in confined spaces. The tools are optimised for size, weight and load capacity.

A special feature of the tools is the composite materials used to produce the hydraulic piston seals. These offer easy piston return, exceptional reliability and long-life performance compared to other seal materials. Even after prolonged use the seals remain firm, do not get dislodged and are low maintenance.

Other important features are an overstroke prevention device and a highly visible maximum stroke indicator. Customer options include a spring return, gear driven nut run-down and single or twin connections. Robust yet lightweight, the tools have been designed to perform a minimum of 10,000 pressure cycles.

All tools supplied to the wind industry have to meet exacting requirements, and Boltight's tools have been specifically designed to suit the technical specifications of the most common wind turbines supplied by the leading manufacturers.

Boltight's Foundation Bolt tensioners can be supplied for all the common thread forms including Standard Metric, Standard Imperial, Macalloy, Williams and Dyson.  All of the Boltight tools are CE marked and supplied with a comprehensive health and safety, operating and maintenance manual.  

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