Hydraulic gantries are a safe, efficient way to lift and position heavy loads in applications where traditional cranes will not fit and permanent overhead structures for job cranes are not an option. When used with rail systems, hydraulic gantries also provide a means for moving and placing heavy loads. Hydraulic gantries are a cost effective solution for many lifting and rigging applications.
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 Jack-Up System is a multipoint lifting system. A typical system setup includes four jack-up units positioned under each corner of a load. A four unit setup has a lifting capacity of 2,000 metric tons (500 tons per unit). The lifting frame of a jack-up contains four hydraulic cylinders in each corner which lift and stack steel boxes. A load is lifted in increments as boxes are slid into the system, lifted, and stacked; forming ‘lifting towers’. A Jack-Up System is operated and controlled by a computer control unit. Each unit’s lifting and lowering operations occur simultaneously; the computer control unit’s synchronous technology maintains the balance of the load. The hydraulics power units are embedded within each unit’s lifting frame. Safe lifting heights are dependent on the expected side load.
Self-Propelled Modular Transporters
The Enerpac Self-Propelled Modular Transporter (SPMT) features a minimized height and slim design, which makes it very easy to operate in confined spaces. Each wheel unit has a steering function as well as a lifting cylinder at its disposal. Wheel propulsion is established by wheel drives. The SPMT is operated by the Intelli-Drive Remote Controller. This remote controller can be used both hard wired and wireless (based on radio frequency).
Hydraulic Skidding Systems
Enerpac has applied high-pressure hydraulics to create a line of skidding systems. A skidding system is comprised of a series of skid beams moved by hydraulic push-pull cylinders, traveling over a pre-constructed track. A series of special PTFE-coated pads are placed on the skid tracks to reduce friction. The skid beams are then connected by hoses to a pump. Enerpac Skidding Systems are available in several versions.