The life of Ball screw is determined by the flaking caused by fatigue on the rolling surface.

Please check the approximate lifespan using this expected travel distance graph.

However, if there is a lot of impact or if proper lubrication and maintenance are not performed, the expected travel distance will be significantly reduced.

Expected travel distance (km) = Actual load stroke (m) × frequency of use (times/day) × number of operating days/year × 10^-3 × expected number of years

The graph below is based on L10 life.

L10 life is the lifespan that 90% or more of the total can achieve, expressed in travel distance.

When selecting a jack based on its lifespan, please select the frame number from this graph as follows:

In this graph, the expected required travel distance is 5km and the PM equivalent load is 39.2kN{4tf}.

The intersection of each point is the required jack size, in this case JWB050 or JWH050 type or higher jacks can be selected.

If the load fluctuates significantly during the stroke, calculate the equivalent load using the following formula.