Hooked on you

28 October 2021


You have a crane, you have a hook. What more could you need to lift your load? The answer may be ‘plenty.’ You need to attach the hook to the load but the environment may be too hot or too hazardous for a person to do the attaching. Some loads may have no lugs for the hook to fit into, so you need slings. But slings may rub against the load and damage it. And once the load is off the ground it may spin out of the orientation that you need. Julian Champkin looks at below-the hook attachments that can help.

Lifting is rarely as simple as it seems. The difficulties can start at the hook itself. Attaching the hook to the load usually requires someone to put their hands in the region between the two – with obvious risks. There are solutions. The Gigasense Automatic Safety Hook from Swedish company Gigasense does the job automatically. It hooks up, locks safely, and releases, with no need for anyone to be in the loading or drop zone. Risk of injury is therefore dramatically reduced.

Unlike many specialist attachments it is a completely mechanical device, needing no batteries or power supply. The open/close mechanism operates when the hook rests on the load and settles to an angle of 60 degrees or less. This cannot happen until the rope is slack.

In that position the hook can be maneuvered to the lifting point; when the rope tightens, the hook closes and latches. Once a load is suspended on the hook, the hook will never let it go; it can swing back and forth safely with no fear of accidental release. To release the hook, it must again settle to angle of 60 degrees or less, which cannot happen until the hoist rope is slack and is not under tension.

Because the hook is completely mechanical it can also be used in water and other liquids. “For example it is often used in hot galvanization plants, where fumes make it dangerous to have people nearby to unhook,” says Gigasense marketing director Malin Nordin. “It is used in wastewater and sewerage works for the same reason. In industries where work needs to be done on heavy equipment, for example on aero engines or heavy diesel engines, the Gigasense hook keeps the engine safely hooked in the air while it is being worked on.

“Other applications can be loading and unloading trucks or similar work at height.” The Gigasense Automatic Safety Hook is available in sizes from 2 tonne up to 27 tonne capacity.

FLEXIBLE RIGGING OPTIONS

Spreader beams have long been used to carry long, wide or large loads. They are simple in concept: basically a metal bar with attachment lugs at both ends and one would not have supposed that much in the way of technology or development could be applied to it. One would have supposed wrong.

Modulift, for example, has its modular spreader beams, with components that bolt together to provide whatever length of beam is needed for each particular job.

This summer they added a new product to their portfolio. Their clevis drop link and delta plate attaches to the ends of the beam to carry the load and is designed to replace their standard drop link for certain rigging situations. The different sizes of delta plates are suitable for various bottom shackles which can be installed in the same clevis drop link, which makes the product compatible with a range of shackles and therefore extremely flexible. It quick and easy to assemble on-site, with two smaller size shackles replacing one large lower shackle which you would see in a standard spreader configuration.

“Feedback from site trials have confirmed that the product is really easy to use and saves time rigging up, especially when doing repetitive lifts” says John Baker, Modulift’s commercial director.

Lattice spreader beams, as opposed to solid ones, are suited to longer, lighter loads. Lifting beam manufacturer Britlift has recently brought out a new, larger, size: it is modular, and has a six-tonne working load limit. This, it says, is the largest capacity lattice spreader beam on the market.

It comes in two sizes, the LAT-3 with three-tonne and LAT-6 with six-tonne lifting capacity. It has been designed to lift loads of up to 44 m in length and has 44 lifting connections for attaching anywhere along it.

Britlift says its engineers designed the system with transportation, storage, handling, and self-weight as priorities. Some applications it suggests include lifting roofing sheets, long pipe sections, bundles of tube or bar, sections of rail and even wind turbine blades.

LIFTING MODULAR UNITS

Modular housing - what used to be known as prefabrication - served Britain well in the aftermath of World War Two, when ‘prefabs’ housed families facing the housing shortage from bombing. The technique is again beginning to gain traction in Europe, for both low- and high-rise buildings; speed of construction, affordability, green credentials and lack of reliance on increasingly-scarce skilled labour are just some of the reasons.

Across the Atlantic prefabricated walling units, and, taking it further, the modular house – where entire rooms are manufactured off-site then transported and craned into place - have never gone out of fashion and are standard. Lifting an entire factory-made room – floor, walls and roof - from a truck without damaging it, then positioning it exactly adjacent to the room next door with no gaps, is not simple.

A Canadian company with the appropriate name of Below-The- Hook, however, has come up with ingenious aids specifically designed for the purpose.

Its BTH BX 6PT is a four- or six-point lifting frame kit consisting of seven manually-adjustable spreader bars and four corner connections. It can be assembled into a rectangle of exactly the footprint of the module to be lifted, up to a size of 20 foot x 45 foot (6 metres x 14 metres). In this way the lift at each attachment point of the module can be exactly vertical. This versatility reduces the flex on the boxes.

The company’s patented Autobox BTH BX 18/30-20/34-45 model has added sophistications. It is a ‘folding for shipment’ design which eliminates field assembly. The spreader bars are auto locking into the preselected lengths, and only one rigger is required with the crane doing all the lifting. “This greatly reduces labour costs and reduces risk of injury because very little manual lifting and pulling is required compared to standard types of spreader bars,” says CEO Bernie Sandrowski.

Average set up time for the Autobox frame is ½ to ¾ hour fully rigged, which reduces crane and labor time significantly. An eight-point configuration kit of additional spreader bars is available which allows handling of modular boxes up to 30 foot (9 metres) wide by 76 foot (23 metres) long.

An associated problem when setting modular units next to one another is the clearance needed for the lifting slings. This would normally prevent two room-units being placed actually touching one another. Instead they have to be set as close to each other as possible and then jacked sideways the last few centimetres to close up the gap. Below-the-Hook has a solution. Instead of slings they can supply lifting bands, thin flexible steel strips each 50 foot (15 metres) long by 2 inches (5 cm) wide, and each about the thickness of a saw-blade. For that reason they provide near zero clearance requirements. “Therefore you are no longer notching the sill plates or the tops of modules to accommodate removal of the sling,” says Sandrowski. “Also units can be set side by side tight and no further sliding of the units is required. The bands are cut and left in place, or they can be cut on one side and the crane pulls them out as the rigging is lifted up.” Each band is a one time use only, though it is recyclable. Custom lengths can be provided; and, like all Below- The-Hook lifting products, they are built to or exceed ASME BTH-1- 2011 standards.

LOAD ORIENTATION DEVICES

We wrote a couple of years ago (November 2019) about two new Australian inventions, both of them designed to eliminate the rotation of loads. Aligning, say, a cladding panel against a tower block has to be done accurately, and such a load spinning in the wind suspended high above ground from the hook of a tower crane is nobody’s idea of efficiency or safety.

On construction sites worldwide alignment up till now has been done by using rigging ropes, ‘taglines’, trailed from the suspended load and held – dangerously and often with difficulty - by workers on the ground or – more dangerously still - by workers high on the building trying to get hold of and control the load as the crane operator gets it as close to them as he dares.

With the new devices, neither taglines nor an expensive, and scarce, ground force are needed. The load can keep the desired alignment throughout the lift no matter what wind forces act on it. It is controlled by a suitably-placed observer with a remote control.

The Australian devices, from Roborigger and from Verton, work on different but related principles. When we last wrote, both companies were recent startups, at the introduction stages of their technologies. Since then, both have made strides both in development and in worldwide acceptance and sales.

Roborigger is based in Perth. The first use of its product was on the new Western Australia Museum, also in Perth, in 2018. Since then numerous units have been operating around Australia, including on Melbourne’s Australia 108 tower, which houses the highest residences in the Southern Hemisphere. The company has shipped units to Singapore, Dubai, Germany and elsewhere, and oil and gas operators are also using it.

The Roborigger unit hangs from the crane hook and the load in turn hangs from it. It contains a vertical flywheel with fan blades attached; a lithium-ion battery rotates the flywheel-fan assembly, and as managing director Derick Markwell puts it, conservation of angular momentum sorts out the rest. “If you accelerate the flywheel anti-clockwise, then the load hung beneath it will rotate clockwise. As well as that, the fan blades give a continuous torque.”

So if wind forces, or rope torque, start to rotate the load clockwise, then accelerating the flywheel also clockwise will tend to spin the load anti-clockwise; get the speed right, and the load will not rotate at all.

New technology in development for Roborigger includes a voice-operated control system and a novel data capture system that allows all load movements by Roboriggers anywhere in the world to be automatically captured recorded and made accessible on the web.

In July this year the company expanded by opening a new manufacturing plant in Wangara to the north of Perth. The facility will allow it to scale its manufacturing operations to meet demand that has arisen in Europe, Japan and other markets.

Also in July came the announcement of an agent, JOTO Sangyo Co. Ltd, to represent them in Japan, and a cooperation agreement with JOTO and Sumitomo Mitsui Construction Co., one of Japan’s largest construction conglomerates, to use the Roborigger system in its SQRIM fully precast concrete construction method for high rise building.

And in September Roborigger entered into an agency partnership with Ludwig System, a manufacturer of radio-controlled crane hooks based in Germany, who will now lead the development of Roborigger business and operations in Germany, Netherlands, Austria and Switzerland.

“We are now seeing Roborigger deployment picking up speed exponentially. We will have Roborigger working on Sydney and Auckland metro projects, mega projects in Dubai and Abu Dhabi, a shipyard in Germany, building powerlines and handling loads in the northern Australia and loading equipment onto supply boats for offshore drilling,” Markwell said.

Verton, based in Queensland, launched its anti-rotation below-the- hook devices at around the same time. Its product resembles a spreader beam but contains fast-spinning gyroscopes, again battery-powered and remotely controlled. They are modular: several can be joined together to control the required scale of load. Their brands are now the Everest series, for onshore work, and the Columbus series for offshore.

Verton too has been signing worldwide, and prestigiously. In September 2020 international heavy lift specialists Mammoet signed agreements to introduce Verton’s products to its customers; offshore operators Global Gravity have done the same; and Verton’s products have been approved for use within oil giant Shell and have been trialling on several of their sites.

In April this year Verton signed Red Rooster Lifting as its first distributor in the UK. In the US the Crosby Group completed a significant investment in the company in February this year; the two companies will collaborate to accelerate the adoption of the technology. Also in the US Hale Steel has ordered three Everest SpinPod 7.5’s for their construction operations. Hale Steel used Verton’s gyroscopic modules to install massive modular insulated metal wall panels on a project in Little Rock, Arkansas. The panels were 32 feet wide, 60 feet tall and weigh 10 tonnes. Hale Steel used a Verton Everest 6 lifting beam to lift and precisely orientate the concrete panels remotely. Installing eight modular panels for one of the walls would usually take six days, but Hale was able to do it in just three: Verton’s remote control orientation meant that a single worker could direct a 10 tonne panel while standing a safe 35 metres from the load.

In September, Indian pre-cast company Dal-Lago signed up to distribute Verton products across the sub-continent. The company has orders from the UK, Germany, UAE, India, North America, Singapore, Malaysia and South Africa and has signed up three more distributors with a further 14 global distributors in the pipeline. And it has delivered two Everest SpinPod 7.5’s to Danish wind turbine manufacturer MHI Vestas for deployment in the North Sea off the coast of Aberdeen.

Verton is also progressing the proof of concept for its ‘WindMaster’, designed specifically for lifting and orientating wind turbine tower sections, nacelles and blades without the need for taglines. Using Verton’s wind vane and gyroscopic technology for load control is intended to solve critical issues caused by strong winds and unstable working platforms during installation and maintenance on or offshore.

It would seem that orientation devices, from non-existent three years ago, are set to join a host of other below-the-hook attachments to become a standard tool worldwide.

The Autobox from Below-the- Hook in action
Britlift’s lattice spreader beam, illustrated lifting a roof panel
The Autobox from Below-the- Hook in action
The Modulift clevis drop link and delta plate speeds on-site rigging of spreader beams
Verton’s Everest spinpods prevent rotation
The Modulift clevis drop link and delta plate speeds on-site rigging of spreader beams
A Roborigger at work in Japan
Verton’s Everest spinpods prevent rotation
The Gigasense hook latches and releases automatically