Skidding a 1760t module

17 July 2019


Fagioli was contracted for the weighing, load out and load in operation of a 1,760t manifold module in Kazakhstan.

One of the tasks Fagioli was contracted to perform was the weighing of the module, which was 80m long, 8.7m wide and 11m high.

To execute the weighing operation Fagioli used 18 300t-capacity hydraulic jacks and eighteen calibrated load cells—14 of 200t capacity and four of 300t capacity. A hydraulic power pack unit (HPPU) with synchronous lifting system was also used. A suitable number of readings were recorded and CoGs were calculated.

After this process, the company proceeded with the skidding operation. The length of skid tracks was about 106m. The pulling system consisted of two L450 strand jacks, with minimum safe working load of 418t. Each strand jack was equipped with 27 strands with a safe working load of 15t each for a total capacity of 810t.

Other elements of the pulling system included: power pack unit, strand jack support and pulling connections.

Fagioli strand jacks move structures in a series of increments roughly equivalent to the stroke of the hydraulic jack (approximately 450mm). For the purpose of pulling operations the jack piston is simply extended and retracted in sequence. The wedge gripping mechanisms automatically lock onto the strand cable and pull it through the jack as the piston extends, and then lock it in its new position as the piston retracts to reset.

Releasing the cable is slightly more complicated, requiring secondary hydraulic systems incorporated in the gripping mechanisms to override their automatic operation. This allows the jacks to be opened without pulling during resetting and allows the cable to pass through the lower grips when actually releasing the cable.

The strand jacks managed to pull the module onto dedicated skid tracks and eventually onto the barge. Once loaded, the barge moved to an artificial island where the module was skidded by Fagioli strand jacks onto the land. Ballast and engineering operation for the load in action were executed under Fagioli engineering division responsibility.

Skidding the 1,760t manifold module
A close up of the strands during load out
Looking along the skid tracks to the module during load in
Weighing the module with climbing jacks and load cells