The strand jack lifting technique originates
The strand jack lifting technique originates from the concrete post tensioning principle. A strand jack can be considered a linear winch. In a strand jack, a bundle of steel cables or strands are guided through a hydraulic cylinder; above and below the cylinder are anchor systems with wedges that grip the strand bundle. By stroking the cylinder in and out while the grips are engaged in the anchors, a lifting or lowering movement is achieved.
The motion of the cylinders is driven by hydraulic power packs. They can be electric or diesel powered. Our sophisticated SCC software program synchronizes the motion of the strand jacks and adjusts the motion to the loads per lifting point.
Enerpac strand jacks are available with two types of strand: a standard strand of 15,7mm and compact strand of 18mm. The 15,7mm strand can work with a dynamic load of 110kN. The 18mm strand can work with a dynamic load of 155kN. The number and type of strands used in a jack determine the safe working load of a jack. For lifting applications Enerpac strand jacks are calculated with a 2,5 safety factor against breaking load to working load.