A STEEL STRUCTURE FRAMEWORK FOR THE NEW BOILER HOUSE

The erection of the steel structure framework was undertaken for the new boiler house, leaving a section open to crane in the coal-fired 14t steaming new boiler.

Access for the abnormally wide lowbed at 3.5m was restricted. The high concrete plinth posed safety concerns for the riggers and boiler as a result of the plinth height. The 50t boiler had to be jacked and moved into the final resting position.

Due to space constraints on-site with building works, the initial methodology was to hand rig the 50t boiler off the lowbed transporter. This was moved towards the two 560mm high concrete plinths using a special jack ‘n slide hydraulic pack with ram cylinders on railway lines.

On project commencement, Reef Rigging would need to change out 2 x BS2970 461 model stripped JT boilers; 5t steaming 22t dry mass and all accessories; steam, feedwater and blowdown piping modifications at Vuka Commondale Treated Timber in Paulpietersburg by collaboration of Reef Rigging and Boiler Industrial Plant.

How Reef Rigging helped

The project was hampered by persistent rain until an executive decision was made to replace the jacking method and opt for a more expensive but much safer mobile crane method.

This meant that the structural steel project could go ahead, provided it was possible to set up a large 220t mobile crane on the site within rated lifting capacity.

Once carried out, this proved hugely successful when the 220t mobile crane was able to lift the 55t boiler mass over the structure within a 12m horizontal radius.

The outcome

Aside from eliminating the safety concerns, and from a possible 4 days on-site, the entire erection process of the structure was completed in 1 day, and the 50t boiler installation was done in 1 day. This resulted in substantial build savings for the client’s benefit.