Gallery - SGR Gantry Cranes Assembly
To lift the 140 Tonnes Bridge Girders, this work is undertaked by mamoth cranes which can lift up to 80 tonnes. The gantry cranes move along rails and are mainly used to hoists loads at the site.
Gantry cranes are a type of crane built atop a gantry, which is a structure used to straddle an object or workspace. They are also called portal cranes, the "portal" being the empty space straddled by the gantry. The terms gantry crane and overhead crane (or bridge crane) are often used interchangeably, as both types of crane straddle their workload.
The usual distinction drawn between the two is that with gantry cranes, the entire structure (including gantry) is usually wheeled (often on rails). By contrast, the supporting structure of an overhead crane is fixed in location, often in the form of the walls or ceiling of a building, to which is attached a movable hoist running overhead along a rail or beam (which may itself move)
The gantry cranes at Section 7 serve the propose of lifting the heavy T-Beam girders and also steel rods during production. Their movement is limited to only back and forth are are controlled by an operator, whose chamber is on the gantry itself. Moving on railway steel the gantry cranes are of two types depending on the maximum load to be hoisted.
The following gallery shows some basic steps how these gantry cranes are installed on site. To note, they arrive as parts on flat bed trucks and are then installed.
Going by the Skills Transfer program for the Standard Gauge Railway, assembly of the above gantry cranes started out by apprenticeship and by the time the 18 cranes where installed, most of the work was done by the locals who had gained the knowledge.