Silo rigging installation
Reef Rigging undertook a project to move 2 silos at Fairfield Dairy in Howick West recently. The project had its challenges, but these were overcome and the silos were successfully moved
- Project scope:
Due to demand for their product, Fairfield Dairy intends to increase its yoghurt processing facility by changing out the capacities of the raw milk silos and yoghurt buffer tanks by more than 2.5 times.
- Installation:
Site installation took place:
- externally to exchange 2 x 30 000L silos for 2 x 80 000L incoming new raw milk silos;
- and internally at the Howick West processing facility via the roof opening to access and move the larger yoghurt buffer tanks in the Production area out by crane and insert the replacements.
- Lifting resources and equipment:
The first part of the project took one day to safely offload the 2 x 80 000L silos from incoming transporters to ground using two crane trucks. This was accomplished in tandem operation so as not to flex the spine of each tank, whereafter the silos were put into a temporary lay down area on cradles.
Given the weather variables of wind and rain, a suitable forecast of at least one continuous sunny day was selected. This would be used to remove and rehabilitate the roof sheeting and insulation, and complete the internal tank change out. Likewise, two sunny days were required for the external change out of the raw milk silo installations with the modifications to their walkways and ladders.
Large mobile cranes (of 150t and 55t rated capacity) were the only lifting resources specified to safely meet the extended horizontal radius, height and weight requirements of the tanks working over the roof.
Moreover, the challenge was working in conjunction with other pipefitter and roofing specialist contractors due to the time constraints of the assignment.
- Obstacles:
Because we were working at height elevation, wind velocity of less than 7m per second and a combination of seasonal rain would have resulted in immediate suspension of lifting activities at substantial project cost.
Further complications arose when incoming milk deliveries required space and time for discharge into adjacent raw milk silos, mindful that we were working in an operational 24/7/365 fresh product factory environment.
- Overcoming obstacles:
There were a few tasks that needed seeing to in order to enable us to overcome the mentioned obstacles:
- Reliance on accurate hourly weather forecasts from multiple sources.
- Rescheduling of incoming milk deliveries from dairy farms.
- Positioning rigger banksmen at strategic elevated points with 2-way radios to guide the trajectory and lift path of the tanks by the rigger supervisor and crane operator.
- Ensure the crane hook is directly over the tanks with loads hanging 100% vertically.
- Ensure that the tanks and silos remain safely clear of the boom during the crane up process, and are safely controlled and guided between adjacent structures throughout the lifting path with 18m taglines.
- Project timeline:
The project timeline was 4 days altogether.
If you are needing someone experienced to help you with your project and want to take a look at the work we have done, feel free to visit our website.
You can also contact Chris on +27 (0) 82 659 3315 or admin@metalprojects.co.za.