Lifting equipment manufacturer Modulift teamed up with Siemens Heat Transfer Technology (Siemens HTT) to design bespoke rigs for lifting modules each weighing approximately 200 tonnes.
The two vertical Benson-type heat recovery steam generators (HRSGs) first needed to be lifted aboard a vessel in South Korea for transportation to Thailand.
Modulift sent two rigs, one for loading and a second for discharging, to South Korea and Thailand respectively. Each rig comprised of eight 34-tonne capacity MOD 34 beams in addition to slings, shackles, tie-plates, and other rigging gear.
Dennis de Jong, supply manager for Siemens HTT, said that the HRSG modules are the largest the company has ever constructed. This presented a rigging challenge given the dimensions involved, principally because slings would have needed to be rigged at an acute angle from an existing lifting beam to connect to the load’s pick points.
The solution was based on utilising the existing beam, beneath which eight 3.25 m-long standard spreader beams were rigged at a 90 degree angle to the larger beam. This widened the below-the-hook system.
“The result was a mix of the old and the new with an existing beam rigged above the new beams beneath. The use of wire rope slings was also carefully planned to ensure maximum safety and efficiency,” said de Jong.
Chris Schwab, account executive at Modulift, added: “Siemens wanted to utilise the same pick points so we were steered towards the eight-beam solution; we added another layer to the rig. Above each beam, a sling was rigged at either end at a 55 degree angle to a tie-plate, with an 18-tonne safe working limit (SWL); between the plates, a 17-tonne SWL tie grommet sling provided stability and attached our rig to their beam.”
The HRSGs will be installed at the 1,300 MW South Bangkok phase one combined-cycle power plant, located 20 km south of Bangkok.