The bronze bushes/bushings/sleeves are made by centrifugal casting relating to the speed importantly and two points should be taken into consideration: the speed should ensure the metal liquids to form a cylinder colour and rotate with the shaft; secondly make use of the centrifugal forces to ensure the inside quality to avoid the defectives of  the shrinkage, porocity, inclusion and so on. The materials have tin bronze, aluminium bronze, and special bronze, which need different temperatures