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Support
Sam , the following is a diagram of an expansion joint :
Sam , your planning and layout is very important , and the following points should be considered prior to commencement of work :
• Consider gas , water and electrical lines
• Make sure the customer ’ s requirements have been met
• Make allowances for possible extensions
• Routing should be in accordance with codes of practice
• Mechanical protection may be required
• Place a draw wire into the conduit as work progresses .
• In cold weather , gentle heat can be applied prior to forming bends . Rubbing with hands is often sufficient .
• Conduit should be saddled at ± one-metre intervals .
• To ease conductors through , a light smear of liquid paraffin or French chalk can be used .
• Bends should have a minimum radius of six times the inside diameter of the conduit .
• Correct spring bender size should be used .
• Care should be taken when using PVC conduit for light suspension due to the heat generated by some fittings .
Light and heavy-duty conduit is available in 16mm , 20mm , 25mm , 32mm , 38mm , and 50mm as well as flexible PVC conduit which is also available in multiple sizes .
When marking out , the following procedures should be followed :
• The position of all components should be determined and clearly marked
• Individual conduit runs should be marked out using a plumb line and a spirit level
• Accuracy is very important
High standards can be achieved by :
• Thorough planning
• Attention to detail
• Constant practice
• Pride in your workmanship
Thanks for your question , Sam , and I hope that this helps you with your work with conduit .
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RACA Journal I September 2023 www . refrigerationandaircon . co . za