The drill rig is designed to take core samples from the seabed at 3000m 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 subsea 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 iglidur® X from igus® was ultimately chosen.
British Geological Survey