SPIDERS EASE PRESSURE OF CHRISTMAS PREPARATIONS

04 December 2009

Spider machines team up to ensure Christmas light spectacular is ready for Mariah switch-on at Westfield London shopping centre. A spider crane and spiderlifts have solved ground pressure and narrow access constraints in the installation of a unique Christmas light display at one of London’s most prestigious shopping centres.

Lighting specialist, The Lite Fantastic, has installed a stunning cascade of 700,000 LED lights around columns to the towering 32m high atrium at Westfield London shopping centre, Shepherd’s Bush. The first of its scale and design to be attempted in the UK, the dazzling festive display was completed at night during a tight 3 week schedule. Global singing superstar, Mariah Carey, delighted Westfield London shoppers when she dropped in to perform the official switch-on during her recent UK promotional tour.

Technically complex and logistically demanding, installation of this spectacular lightshow relied on a unique pairing of ‘spider’ engineering. A 19.5m UNIC URW-706 mini spider crane, on hire from equipment specialist, Coppard Plant Hire, was used to hoist two Teupen spiderlifts to first floor level (level 50) to work in the difficult atrium space. Teupen spiderlift rental specialist, The Spiderlift Company Ltd, supplied the two tracked spiderlifts, both Leo 23GTs with 23m working height (w/h). They also supplied a Leo 30T with 30m w/h to supplement access working off the ground floor (level 40).

Floor loadings

Loadings from the 3 tonnes spiderlifts and 6 tonnes lift capacity UNIC crane were submitted for approval by Westfield London’s structural engineers to ensure they met the Centre’s criteria.

The Leo 23GT platforms generate a low surface load of < 1.8 kN/m², in set-up and travel model, which comes well within the 5 kN/m²surface load limit typically required in shopping centres.

Chris Connolly, director of The Lite Fantastic, said: "The lights for Westfield London are a one-off, bespoke installation, and were very difficult in terms of health and safety and working in a very new, high specification mall. Lights are usually hung from point to point but this involved wrapping nets around the arms and main columns of the atrium ‘tree’ supports at heights up to 32m."

The Centre had initially considered rope access using abseilers to install it, but it looked impossible in the atrium space. After seeing Teupen’s spiderlift capability, Chris Connolly realised there was a safer and more efficient solution to the problem.

The 700,000 LED unit display is made up of 144 individual nets, measuring 8m by 1m and weighing around 12kg each, and draws 88Kw of power with length of supports of 32m.

"We could get access to virtually any part of level 50 using the combination of two Leo machines on the balcony and the larger unit working from below," he said. "The Leo 23 also has a compact footprint allowing us to slim the machine set-up for access to one particular tree column on a narrow part of the balcony."

The platforms have an unusual combination of a lower telescoping and upper articulated boom, as well as a fly jib. This offered efficient speed and manoeuvrability in weaving around the splayed supports extending from the columns to fix the nets.

Chris Connolly commented: "We were working intensive shifts between 10pm and 8am, so it is always an advantage to use equipment that makes the job less frustrating and less tiring for the operator. Platform set-ups take time and can tire operators, but we only needed to set up the Leos three times for each tree column where other lifts would probably have taken four or five."

Other key features of Teupen spiderlifts include narrow widths, low weight, low surface loads and ground bearing pressure, plus cushioned load-dispersing tracks and stabiliser feet which are all non-marking. Leos also offer failsafe and dynamic staging ability on all types of ground conditions – including levelling on slopes and straddling seats or steps. Very responsive and simple controls allow fine and effortless adjustment in the air, vital when working close to high value glazing and architectural finishes.

These capabilities make them especially suited to the sensitivities of interior floor loadings and high value environments found in shopping centres, churches and heritage buildings.

More on the Teupen spiderlifts

Chris Connolly of The Lite Fantastic said: "The Leos are very reliable, very manoeuvrable and very easy for operators to use. They give excellent, responsive fine control over machine positioning, and the control box layout is very logical, straightforward and user-friendly. Even the Leo 23 has the sensitivity of control you would usually only expect from a bigger machine."

He added: "We have an outstanding IPAF qualified instructor, Joe Ennis of Access All Areas Ltd, who was able to train up eight of our guys to use them very quickly and successfully."

UNIC mini crane

The UNIC URW-706 is the largest mini spider crane in its class, with narrow 1600mm access width, low ground pressure and point loads, as well as a big capacity-to-weight ratio. This made it the only feasible solution for lifting the spider platforms up to atrium level.

Coppard’s crane & glass handling manager, John Wilding, said: "The key issues for us were the tight entry width to the job and the ground pressure limitations with the floor being over a basement car park. Once we had surveyed the site together with Spiderlift personnel, we were confident that the URW-706 met all criteria."

He continued: "We set the crane at the right radius and angle to raise the spiderlift, then simply rotated to clear the glazed panels on the balcony. Coppard Plant Hire supervised the lift from start through to completion and it took just over an hour to lift the two platforms safely onto the atrium floor."

The URW-706 has a 6 tonne capacity at 3m and a hook height of 19.5m, and is the highest capacity mini-spider crane in the UNIC range. A big beast in terms of mini cranes, at just 1600mm wide it is still narrow enough to gain access through a standard double doorway. For added lifting flexibility, the 706 also features an optional 3.1m long stowable fly jib, together with an optional searcher hook. Maximum working radius is 18.6m and maximum boom length is 19.2m, and mains electric powering comes as an option.

Service support

Pressures on lighting contractors to complete major Christmas installations on time and on budget are immense. The Lite Fantastic had limited time to get machines in, carry out the work and make way for other contractors to complete their tasks ready for the Christmas switch-on.

"Running over the lighting schedule by even a day was not an option," stressed Chris Connolly. "If this had happened due to breakdown or poor service, it would have cost another three weeks hire as we would have had to leave the machines on site."

He added: "It was extremely reassuring to be dealing with a Spiderlift Company director on such a critical and pressurised contract. We had a direct line of communication with Andy and his team who gave us a prompt response on any query, and extremely fast support on site from a service engineer on an issue early on in the project."

Spiderlift Company MD, Andy Bray, visited Westfield London well in advance of the job to survey and advise Chris on the application. He also met with Joby Coppard, Coppard’s plant manager, to discuss and resolve the technical tie-up between the Teupen spiderlifts and the UNIC mini crane.

Andy Bray said: "Although the recent job at Westfield London was particularly challenging, the work which Teupens typically take on is often technically demanding. They will involve heights, locations and floor loadings that are beyond the scope of conventional lifts. The applications are often unknown territory for FM clients and their contractors, making it all the more important to hold their hand with high levels of service including technical consultation and site back-up."

Andy made a further visit to attend the craning of the platforms, advising on any issues as they arose during the lift. He was on hand to give guidance on chain positions on the machines and to help oversee the safety of the operation.

Chris Connolly said: "Working with Andy and the Spiderlift Company has been nothing less than excellent in every respect, including the platforms, price structure, service and all-round professionalism. In my role, I have a very limited time to spend sourcing and organising equipment so it is only worth dealing with people who are reliable and efficient. It makes a big difference to my time management and cost-effectiveness."

Fit-out contractors used Teupen Leo spiderlifts for electrical, H&V and other interior work during construction of the £1.7 billion mall. The centre itself regularly hires machines from The Spiderlift Company for maintenance and other ‘at height’ tasks.