Nutrunner benefit is more than just torque

An automated fastening system developed for the car industry may have spin-off applications for manufacturers of brown and white goods and for other sectors. The TNA1 nutrunner, which tightens nuts and bolts, is believed to be the first in the world to be driven by an AC motor. It is said to have the benefits […]

An automated fastening system developed for the car industry may have spin-off applications for manufacturers of brown and white goods and for other sectors.

The TNA1 nutrunner, which tightens nuts and bolts, is believed to be the first in the world to be driven by an AC motor.

It is said to have the benefits without the disadvantages of either DC motors or pneumatically powered systems.

Advantages include a final torque accurate to within 4%, similar to a DC system and around five times better than a pneumatic system. The maintenance problems associated with DC equipment are avoided.

Energy consumption is said to be 1% of that needed to operate pneumatic tools, while capital cost is around half that of a DC unit.

The TNA1 is designed to be built into special rigs for tasks like wheel assembly.

Computer control of the system ensures that safety-critical components such as wheel nuts are tightened to the correct torque and angular rotation.

The tightening process is shown on a torque curve which highlights problems such as a cross thread.

Developed by Estic in Japan, the TNA1 achieves a maximum torque of 784Nm at a rate of 740rpm. It is available in the UK from Yuasa Warwick Machinery in Warwick.