Example calculations for single-row ball slewing ring

1. Capacity of slewing ring:

2. Loading calculation:

3. Safety factor calculation:

Example calculation for 3-row-roller slewing ring bearing

1. Capacity of slewing ring:

2. Loading calculation:

3. Safety factor calculation:

Table of slewing ring factors (fs)

Light duty Not often at full capacity, slewing steadily,with little force. Material fetching machinery, truck-crane, non-port use wheel-crane. 1.00~1.15
Medium duty Not often at full capacity, slewing fast, with some force. tower-crane, boad crane, ped-rail-crane 1.15~1.30
Heavy duty Often at full capacity, slewing faster, with greater force grab-bucket-crane, port-use crane, single bucket excavator, Container crane 1.30~1.45
Types Features Examples fs
Extremely heavy duty Always at full capacity, slewing much faster with much greater force, or extreme external environment. bucket wheel excavator,tunnel borer, metallurgy crane, offshore platform crane 1.45~1.70