Dutch crane rental company and rigging manufacturer Peinemann had lots of experience with replacing heat exchangers. For 30 years, it has sold hundreds of pullers, which use hydraulic cylinders and a special balancing mechanism to swap out heat exchangers. But once the heat exchanger is out, it still needs to be lifted on to a flat bed truck for transport.
Heat exchangers are seriously awkward loads. First, they are long (up to 8m (24ft)) and heavy (sometimes more than 20t). Second, since they are made of a bundle of pipes welded together, their exterior cannot bear their own weight. If a rigger wrapped a normal chain or wire rope sling around the exterior, the sling would cut into the load, bending or crushing the exterior pipes and metal flanges.
“When something is damaged, Peinemann always gets the blame,” says Leo Mizelmoe, Peinemann crane director. “The main reason we developed this was because the bundles are not designed in a way that they can be hoisted easily-with shackles and a spreader beam above-in a way that does not damage the tubes, the baffle plates and the tie rods.
“There are certain API and KEMA norms for building heat exchangers that were developed 30-40 years ago, and nobody is willing to change these norms. I visit engineering companies, and they say, ‘If the client doesn’t ask for it, we will not change it.’ The clients say, ‘It is not our work to do this, the engineering companies have to do it.’ There is a possibility that nobody will change those norms.
“Now, if we use the bundle lifter, there is no chance to damage someone else’s property. This solves the situation from our side – this is something that is in our hands. Changing the API and KEMA norms, that is not in our hands.”
The bundle lifter has a lifting capacity of 30t, and can lift bundles with diameters ranging from 300mm-1850mm, and lengths up to 8m.
The device looks like a pair of snow shovels turned toward each other. The grab opens each snow shovel and reaches down underneath the heat exchanger, nestling it on a 3.6m-long steel bed.
A total of six hydraulic cylinders open and close the lifter’s four arms. At the top, two cylinders push the grips apart; one knuckle-mounted cylinder mounted on each arm extend to squeeze the grips together. The upper clamps work independently from the lower clamps.
A two-cylinder Hatz diesel engine powers a Danfoss hydraulic pump, which circulates oil at a pressure of 190 bar (2,800 PSI) to operate the cylinders. Holding valves prevent a fall in case the pump fails. The unit itself weighs 4.5t.
A spokesman said that the unit has not been tested on a bundle of loose steel rods. Also, diesel fumes would prevent the unit being used inside. But the firm says that it can customise the lifters or do bespoke design work.
The company has made six pieces and sold three (the price: EUR 82,500 (USD 128,000)). The other three remain in its rental fleet.