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Dollies are used to carry bulky loads and components which can be packed in such a way that moving from place to another is relatively easy. To lift a unit from ground level to the upper floor of a building a builder’s hoist could be used with the permission of the contractor. The mass and size of the unit would have to be considered to decide on the suitability of the hoist for the equipment being moved. A block and tackle (Chain block) is often used to lift items of equipment to a position that is elevated on a building or as a means of moving the item on pipe rollers across a flat surface. To be able to lift an item of equipment the block and tackle must be suitably rated for the mass (Safe Working Load, SWL) and the attachment point above where the lift is to take place is secure. The mechanical advantage will have to be such that one or two persons can provide the necessary power to lift the load and hold it in position. The load must be secured in a sling arrangement that is suited to the size and shape of the load.

Attie, I have covered the planning stages and some of the basic methods of rigging in this issue. In the next issue I will go into more detail with regards to the practical use of chains, slings, hooks, wire ropes, SWL, tags and trifors to name a few as well as additional methods used. REFERENCES: Special thanks to: References ACRA SANS 10296 Occupation health and safety for construction Occupation health and safety act and regulations 85 of 1993 3rd Addition OHS Act MerSETA TG/FG Thanks to all for writing in with interesting questions. I try to answer questions that are of common interest to people in industry. Looking forward to hearing from you – Grant Laidlaw

BLOCK AND TACKLE

Coffing blocks are similar to chain blocks but used when space is limited.

Basic guidlins for rigging  
Basic guidlins for rigging  

We, at our company put in some big air-conditioning equipment. Sometimes we are asked to do some rigging. I see you are giving lots of advic...

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