UK-based hydraulic gantry systems provider LGH Megalift worked with engineering contractor LES Engineering of Grimsby in the UK on the installation of a “receiver hopper” weighing 16.5t. The installation took place at the premises of Knauf Drywall, a UK-based German company that manufactures gypsum and plasterboard products.

“Limited access was the main problem as the receiver hopper had to be installed to project between the first and second floor, standing on 7m long legs,” according to LGH Megalift’s Bob Hamilton. “The hopper itself, with the lid attached, was too high to fit between floors, and using a crane would have meant removing the roof which would obviously have proved costly and time consuming,” he adds.

Following an engineering study, LGH Megalift installed its Minilift system, which is said to have offered a viable alternative to a mobile crane because of its small size, unit weight, and lifting capacity.

The Minilift system comprises four cylinders and two 7m beams. The cylinders are 1.9m at closed height, and can extend hydraulically to 4.9m. These were placed under four LGH Megalift-designed “knee” braces, which were attached to the hopper. The Minilift extended, lifting the hopper through the hole, where it was temporarily blocked into position. Before this could be carried out, the “lid” had to be removed from the hopper to enable the unit to be positioned between the floors.

This process was then repeated with the “knee” braces fixed at a lower level on the hopper, to raise the unit to the required height of 7m; at which point the support legs were attached to the hopper.

The “lid”, which had been lifted through the hole with chain blocks before the hopper installation, was then refitted.

Working in restricted access

In another contract that also meant working in restricted access, LGH Megalift supplied a lifting solution for Dolgarrog Aluminium in North Wales when it expanded its aluminium aerospace production facilities. Three tanks and a furnace had to be installed, the heaviest of which was 40t. The four units had to be configured in a straight line within a 2.5m pit used as part of a heat treatment process.

The second problem was the installation of the furnace, which was the largest of the four units, and had to be sited at the far end of the pit. However, because of a delay in its manufacture it was the last unit delivered to the site.

“Restricted access, due to the close proximity of the building’s roof support columns, meant that it was impossible for vehicles to offload all the units in the main building,” explains LGH Megalift’s Hamilton. In the first phase of its engineering study, LGH Megalift devised and supplied a solution that involved using two jacking systems.

One would be used to offload the units into an adjacent building, overcoming the access problem, and the second to manoeuvre the units into position in the pit.

A 4400 type Megalift jacking system was erected around the pit, comprising two 20m track lengths running down either side. The jacks were connected with 10m beams, enabling them to span the 8m-wide pit. A second 4100 Megalift system was erected in an adjacent building to offload the units from the transport. A skate system was used to pull them through the wall and position them under the larger Megalift using tirfors.

LGH Megalift completed the second phase of its engineering study, and devised a solution to overcome the late arrival of the furnace. The two smaller tanks that were already on site were installed in position in the pit first. The completed furnace was then delivered to the site, offloaded from the transport using a mobile crane, and placed on skates. The smaller Megalift, in conjunction with the mobile crane, had to be used to manoeuvre the furnace in position under the 4400 Megalift, to be installed in the pit.

The 4400 system was fitted with four 15t chain blocks to overcome the problem of restricted headroom.