Week 4 Tutorial - Design of Machine Elements: Bearings and Lubrication

Question 1

A 25 mm (02-series) deep-groove ball bearing carries a combined load of 2 kN radially and 3 kN axially at 1500 rpm. The outer ring rotates, and the load is steady. Determine the rating life in hours.

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Question 2

A 25 mm (02-series) for a single-row, angular-contact ball bearing having 35° contact angle carries a combined load of 2 kN radially and 3 kN axially at 1500 rpm. The outer ring rotates, and the load is steady. Determine the rating life in hours.

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Question 3

Determine the expected rating lives in hours of a 35 mm bore (02- and 03- series) straight cylindrical bearings operating at 2400 rpm. Radial load is 5 kN, with heavy shock, and the outer rings rotate. Calculate the expected rating life of the straight cylindrical bearing if only a 2% probability of failure can be permitted.

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Question 4

Calculate the median lives in hours of a 75 mm bore 02 and 03-series straight cylindrical bearings operating at 2000rpm. Radial load is 25 kN, with light shock, and inner rings rotation