When the bearing is in operation, the rotating part of the bearing carries fresh oil in to the pad area. Fluid pressure causes the pad to tilt slightly, building a wedge of pressurised fluid between the shoe and the other bearing surface. The pad tilt adaptively changes with bearing load and speed. Various design details ensure continued replenishment of the oil to avoid overheating and pad damage. Tilting pad bearings are used in a wide variety of heavy-duty rotating equipment, including in hydroelectric plants to support turbines and generators weighing hundreds of tons. They are also used in very heavy machinery, such as submarine propeller shafts.
The great merits of tilting-pad bearings for marine applications were recognised as far back as 1913. The first English ship to be fitted out with the bearing was the cross-channel steamboat the Paris, but many naval vessels were similarly equipped during the First World War. The practical results were spectacular - the troublesome thrust block became dramatically smaller and lighter, significantly more efficient, and remarkably free from maintenance troubles. It was estimated that the Royal Navy saved coal to a value of £500,000 in 1918 alone as a result of fitting tilting-pad bearings. These bearings are widely used today in heavy-duty rotational equipment. If you have any queries regarding the availability of tilting-pad bearings here in South Africa, please feel free to contact Technoslide on +27 (0) 11 605 2434. We are always ready to advise and assist you.