CRCC鈥檚 biggest TBM main bearing yet has a diameter of 8.61 metres (Image: CRCC)

Chinese construction company China Railway Construction Corporation (CRCC) claims to have produced the world鈥檚 biggest main bearing for a tunnel boring machine (TBM).

The bearing has a diameter of 8.61 metres, making it as tall as a three-storey building.

CRCC said it could be used to drive super-large-diameter TBMs of 18m in diameter and withstand over 10,000 tonnes of load.

It claimed that production of the bearing meant that China could stake its claim to be a world leader in the field of extra-large diameter main bearings.

In a statement, the company said, 鈥淐RCC鈥檚 project team has finally overcome manufacturing difficulties through hundreds of experiments with various processes and materials, enabling the bearing to have a long service life and high manufacturing precision.鈥�