Towering ambition

Cranes are one of the unsung heroes of the construction world. We visited Mantis Cranes on site to find out more.

MANTIS CRANES has manufactured self-erecting cranes in its Donegal factory since 1998. As well as manufacturing cranes, its R & D Department has been working recently on developing a new concept selferecting crane which can be erected in approx 30 minutes from delivery on site, the Mantis TC 25. This crane does not require a low loader trailer to deliver it to the site nor does it require any assistance from other machines such as telescopic forklifts to tow it into position or load ballast weights. If a self-erecting crane or tower crane is not suitable for a project, Mantis also offers mini crawler cranes which are often described as a crane that is small enough to fit inside the building but large enough to do the job.

The company also offers a full complement of crane attachments such as concrete skips, column skips, banana skips, boat skips, self tipping boat skips, rubbish skips, block grabs, fork toes and man baskets from suppliers including Conquip, Eichinger and Boscaro.

Despite having been popular in Europe for many years, self-erecting cranes are still a relative newcomer in the UK sector, but Mantis’ UK sales manager, Brian Owen, is confident of the advantages they bring: “Our cranes are quick and easy to use - we can take the product right to the point of use, and it stays there 24/7,” he says. “Most sites bring in a mobile crane which comes and goes every day – you’ll usually find it de-rigging at about 4pm. On top of that, there are serious space issues with mobile cranes.”

Owen continues: “The cost of one of our cranes for a week is usually same as one or two visits with a mobile, and it’s available round the clock.”

Although the UK construction industry as a whole has been slow to recognise the advantages of self-erecting cranes, the timber frame sector has been ahead of the game, and this sector is probably Mantis’ main customer base. Owen continues:

“On big developments, the main contractor usually sub-contracts to the timber frame contractor with crane costs included. This cost will be based on bringing in a mobile, so if they’re given £20k, we can probably do it for £12k with self erecting, and potentially be finished quicker as it’s there all the time. We’d typically expect to be able to finish a job in about three quarters of the time it would take with a mobile crane. Combine that with timber frame and that’s got to be about as fast as it gets!”

As a final inducement, Owen adds that a self-erecting crane can lift heavier loads by the end of the build as it sits right in place and reaches over the build, with jib length up to 45m. A mobile has to get longer and longer as the building gets bigger.

Mantis doesn’t actually employ operators – usually the contractor will do this themselves. However it does offer a full induction service in controls and required daily checks to those who will be using theequipment on site. Having caught on to the benefits of self-erecting cranes quickly, timber frame companies often have someone on board who is already familiar with the cranes, but Owen laments that this is not the case in the brick and block sector, where training is often seen as an obstacle.

One of Owen’s biggest frustrations is not being to get in at planning stage more often. Indeed, he notes that Mantis rarely even deal directly with the main contractor, and adds: “If we could get in at the outset and talk to everyone that’s going to be using cranes, we could use our self
erecting cranes at all stages from the foundations up. We usually get onward hire at the next stage, but it could all be sorted out at the onset.

“I can only think of one occasion where this has happened, with a steel frame manufacturer, which puts paid to any fears there may be that self-erecting cranes aren’t man enough for groundworks. We’ll just keep plugging away at the big boys and trying to get in earlier. One problem is main contractors often don’t want cranes to be their responsibility. I recently saw a job where we could have put a tower crane onsite which could have reached the whole site and done whole job, but the main contractor didn’t want to. They ended up with three subbies, each hiring in their own mobile crane.”

There’s a lesson in that.