ACTIVE RING FORCE TRANSDUCER Only 10% of the bolted joints need to be instrumented to obtain a reliable picture of the structural condition of the wind turbine
Ring force transducers are pivotal in wind turbines, owing to their beneficial properties that calculate tension and compression forces, says global leader in pressure, temperature and level measuring technology WIKA Instruments product specialist Busisiwe Zikalala.
When the compression force transducer has a through-hole, it is called a ring force transducer, and these force transducers are used in applications and test facilities when a ring geometry with a big inner diameter is required.
Force transducers are robust and suitable for various installation processes and to detect static forces.
They also offer load monitoring, which is achieved when the tightening torques fall below a specified limit or when it falls off and breaks.
“The force transducer F6804 is manufactured at the WIKA facility in Suzhou, China, and can be used as a force-measuring washer if suitably designed,” she mentions.
Zikalala says the signal from the force washer can be amplified using a cable amplifier, suitable for application in environments from –40 ºC to –80 ºC. The cable amplifier also has an accreditation in full IP67 rating.
The washers, used in bolt connections which connect both pillars of the wind turbine together, can easily be replaced by the F6804 force transducer, as it provides more measuring range, between 0 – 3 kN, and 0 – 450 kN, with a relative linearity error of 2% nominal force (Fnom).
Zikalala adds that the force transducer is also easily installed, owing to its compact design.
Further, the EZE09 cable amplifier, manufactured in Offenbach, Germany is another force transducer that can be used in wind turbines. It is suitable for use in environments of between –40 ºC and
80 ºC, with an IP67 rating protection class.
Zikalala says a full load-monitoring system can also supply valuable data during maximum loads in tough environmental conditions.