The drill rig is designed to take core samples from the seabed at 9,843 ft water depth. It is a scientific instrument used in very sensitive environmental areas. For this reason, plastic self-lubricating bearings were selected to eliminate the possible contamination associated with grease in normal bearings. A folding leg system had to be designed and built to take the 5 tonne drill load and also be unaffected by extremes of pressure when used in sub-sea conditions. In addition to this, it also had to be unaffected by low temperatures. The third requirement was a material that would not have cathode effects on the main drill frame in a highly hostile environment. After looking into a number of different solutions, plastic bearings where selected due to the long service life and low environmental impact they offered. There were a number of different grades considered, but iglide® T500 from igus® was ultimately chosen.
British Geological Survey