California, USA-based crane, rigging and trucking service provider Hill Crane Service used a 500 tonne capacity heavy-track HT500 hydraulic skidding system, made by Canadian skidding systems manufacturer Hydra-Slide, to change out a stacked heat exchanger at an oil refinery in Carson, Los Angeles, USA.
The scope of the work comprised the emergency removal of a 260,000 pound (118 tonne) stacked heat exchanger and its replacement with a new 279,000 pound (127 tonne) unit. In addition to the HT500, Hill Crane Service also used 100 tonne capacity modular support stands and a synchronous hydraulic power unit, both from Hydra-Pac.
The exchanger that was being replaced sat on four-feet-high concrete pedestals. Hill Crane Service used crib stacks and pipe stands to support the slide track at an elevation of four feet. The exchangers were skidded a total distance of 29 feet 10 inches (9 metres).
Challenges during the job included the tight deadline, onsite obstructions, and project delays inherited from other contractors.
The HT500 has a total height of 8” (200 mm) which, according to Hydra-Slide, helps save jacking time and means it is well-suited to use in confined spaces. It is engineered for pushing 500 tonnes and pulling 250 tonnes with a standard double track layout.
Darren Scruggs, senior account manager at Hill Crane Service, said, “The slide system was one of the major components of the heavily engineered concept that we pitched to the refinery. Without removing overhead structure beams, a jack-and-slide solution was the only viable option. We worked closely with Hydra-Slide to put together a robust proposal and upon winning the contract, we placed orders for the necessary equipment, which remains in our fleet.”