Before the bushing is pressed into the housing:as the outside diameter of the bushing is bigger than the inside diameter of the housing,strong pressure can be available in the housing. And also this kind of fixing can assure the roundness of the bushing and make the bushing well fixed, voiding abrasion caused by sliding of the bushing in the housing.The interference can be calculated by the following formula:

Min interference       Min OD of the bushing-Max ID of the housing

Min interference       Max OD of the bushing-Min ID of the housing