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In Service Inspection of Wind Turbine Bolts

Project Code: 35601

Start date and planned duration: August 2023, 5 months


  • We will have robustly demonstrated that it is possible to monitor to bolt loosening using acousto-ultrasonics
  • A test bed will have been manufactured to test a variety of bolt types, this can be used for future bolt tests
  • Have the opportunity to demonstrate a new method to customers to generate sales

Project Outline

During installation of an offshore wind turbine, upwards of 1000 bolts are used to secure both the tower section and various other component sections in place. On operational wind turbines, approximately 10% of bolts at key bolted connections are checked annually to monitor for loss of tension. This is a very costly process in terms of both asset downtime and labour.

This project will investigate the use of cost effective piezo-ceramic sensors using a pitch-catch method, to be used to detect variation in force in the bolts. These sensors can be left in-situ to perform regular inspections on a bolt in order to detect any drop in propagation, which would indicate loosening of the bolt. 

Industry Sectors

- Renewable Energy





Oil and Gas

Benefits to Industry

Application of this method to an in-service wind turbine will remove the need for manual testing of the bolts. This will not only lead to a direct saving in person-hours but also increase efficiency and profit by reduction in downtime.


For more information please email: