Factors for calculating the preload of a bearing set

Number of bearings	Arrangement	Designation suffix	Factor
			for preload class
			A, B, C and D	L, M and F
3	Back-to-back and tandem	TBT	1,45	1,25
	Face-to-face and tandem	TFT	1,45	1,25
4	Back-to-back and tandem	QBT	1,8	1,45
	Face-to-face and tandem	QFT	1,8	1,45
	Tandem back-to-back	QBC	2	2
	Tandem face-to-face	QFC	2	2

For bearing sets with five bearings, contact the SKF application engineering service.