Why does a crane boom drift downward while LMI shows no overload?
Boom drift with no LMI overload typically indicates hydraulic seal leakage in the boom lift cylinders allowing fluid bypass.
When a crane boom drifts downward despite the Load Moment Indicator (LMI) showing no overload condition, the most common cause is internal hydraulic seal leakage in the boom lift cylinders. This leakage allows hydraulic fluid to bypass from the rod side to the cap side of the cylinder, gradually reducing the hydraulic pressure needed to support the boom's weight and load.
Remember: DRIFT: Deteriorated seals, Rod bypass, Internal leakage, Fluid contamination, Time for cylinder rebuild.
Keywords
Operators: Add your profile to get matched with jobs. Free.