The girder was positioned so the chain hoists could be slid along to a point above a load, used to lift it to the appropriate height, then slid back again to where it would be unloaded and used within the building structure. I suppose buckets and bricks would be obvious materials.
I immediately thought, how are the loads being monitored? And what was to stop someone who has never used a hoist before hooking up a load far too large for that specific piece of lifting equipment?
The more I thought about it the more questions I rose. Is the scaffolding and what was present of the frame of the building designed to take the girder? How was the weight at different points of the beam considered?
I don’t mean for a minute to say that as soon as hoists and other factory lifting equipment is taken into the construction industry it is misused, far from it, but my eyebrows were raised on this occasion.
It got me thinking about the wide range of ways you see hoists used in the construction sector.
Take rigging safety company Signal-Rite, as an example, which developed a way to lift out a concrete form when one end has been covered by cast concrete.
Signal-Rite has designed, built and had approved a rigging system hung from a construction crane for moving concrete forms out from underneath concrete slabs.
The concrete slab poured on top of the form covers about a third of an 80ft (24m)-long form, including all of one end. The slab obstructs access to the natural lifting points on one end.
The Signal-Rite rigging system consists of a 52in (1.3m) spreader bar and four wire rope slings. Two 7/8in (22mm) wire rope slings run from the edges of the spreader bar to each side of the form just beside the slab. Beneath the chain hoist, balanced with 150lb (46kg) of counterweight, two lines attach to the form about 20ft (6m) from the first two points. Two tether lines keep the hoist from rotating.
Another fascinating project was when a staggering 64 chainfalls were used simultaneously to lift a FCCU (fluidized cat cracking unit) air grid during a maintenance project at Sunoco Refinery in Philadelphia, Pennsylvania, US.
US rental firm Industrial Hoist Services (IHS) supplied 64 chainfalls – manufactured by Kito and Nitchi – for the unique project undertaken by St Louis-based Nooter Construction.
FCCU units are used to produce gasoline fuels. Each is made up of a reactor, a regenerator and a piping process system. The total weight of this particular plate air grid assembly was approximately 302,000lbs.
Perhaps you use chain hoists in the construction market. In what interesting applications have you seen them used? I’d be delighted to hear from you.
If you haven’t done so already, please note that the Hoist team now has different email addresses. The usual prefix will be followed by progressivemediagroup.com.
Richard Howes, Editor
rhowes@progressivemediagroup.com
