SCIENCE AND TECHNOLOGY ENGLIAH FOR MECHANICAL ENGINEERING (F1/F2)=B2/B1 6.6 where F=load (b) and b= life(revolutions). Values of k range between 3 and 4(3 for ball bearings; 3.3 for most roller and needle bearings). Note that for k-3, doubling the load means reducing the life in revolutions by a factor of 8 The relation between B (life in revolutions) and H (life in hours), is as follows B=H×rpm×60 6.7SCIENCE AND TECHNOLOGY ENGLISH FOR MECHANICAL ENGINEERING (F1 /F2 ) k = B2 /B1 6.6 where F= load (lb) and B= life (revolutions). Values of k range between 3 and 4 (3 for ball bearings; 3.3 for most roller and needle bearings). Note that for k=3, doubling the load means reducing the life in revolutions by a factor of 8. The relation between B (life in revolutions) and H (life in hours), is as follows: B = H × rpm × 60 6.7