A Tricky Trip with Six Transformers
Doing what we do best, we take to the road this time with six transformers, each measuring x6m (L) x4m (W) x5m (H) and weighing 185 Tonnes.
The original scope of work involved utilising climbing jacks to load at Grain Power Station, transporting to port on modular axles and shipment by roro pontoon from Thamesport to Goole Docks. The load would then be transported from Goole Docks using a girder bridge trailer for unloading onto a plinth at Drax Power Station by means of climbing jacks. However, these plans were refused by local authorities due to a damaged bridge en-route to Drax Power Station from the Port of Goole. Our Team were required to investigate other means of delivering the loads such as bridge over bridge, indirect routes, and alternative trailer combinations but each one was refused.
Then, when reviewing aerial photographs of the area we noticed that there was a small jetty on the River Ouse, close to the power station, which could potentially be utilised to deliver the transformers.
The roro jetty, owned by Drax Power Station, was built in the 1970’s to facilitate access for heavy equipment destined for the new build Power Station, but it had not been used for this purpose for over 30 years. As a result the river had silted up and the riverbank overgrown with trees resulting in access for a roro pontoon being impossible without considerable dredging, tree removal and other environmental issues.
The Collett Heavy Lift Team proposed using a mobile crane on the jetty, allowing the load to be lifted from a barge and manoeuvred into place but again hit a stumbling block, the jetty width of 9.7m restricted the size of the crane and working radius. After undertaking structural surveys of the jetty a lifting scheme was proposed and approved which involved a 1000 Tonne mobile crane with a minimum outrigger spread capable of lifting the transformers at the radius required.
The execution of the project evolved throughout the planning stages and the method of shipment changed from roro pontoon to a combination of geared vessel and barge. The local authorities and Collett’s client accepted the new proposal with a revised scope of work. The project now followed the format of loading at Grain Power Station with the use of climbing jacks, SPMT moving on site (both at Grain and Drax), heavy transport to port on conventional modular axles and shipment in one cargo to Hull Docks as Goole was not accessible for geared vessels due to the overall length.
The transformers were then temporarily stored at Hull docks before being lifted onto the barge and transported to Drax jetty one transformer at a time. Due to the size of the jetty Collett had to remove the safety fencing and replace with scaffolding to increase the usable width and allow for the placement of 8m x2.1m load spreading mats. Once in place the loads were lifted from the barge and transported to the Drax Power Station where the transformers were unloaded by jacks onto plinths.
The Collett Team provided full project management and continued to complete structural surveys of the jetty after each transformer lift was completed to ensure maximum safety at all times.
