Depending on the size, guidance and bearing, compression springs are at risk of buckling.
When guided by mandrel or sleeve, the spring cannot buckle.
In other cases, it depends on the design of the bearing(EN 13906-1 / 9.14). The spring travel until buckling is referred to as buckling spring travel “sK”.
The following formula is used to calculate the buckling spring travel:
Theoretically, buckling safety is given at “sK /s > 1”.
For more information:
Spring end bearings and buckling limits