Drawings show 42 inch trench with HDPE turning up into primary side of transformer Pad. As Carlon shows 30 X Conduit size radius as min. bending allowed I think factory 90's are required Anyone have experience with this??? Yooperup
Last edited by Yooperup; 07/11/1708:06 AM. Reason: Mistake
As long as the bends do not decrease the ID of the raceway and do not use a radius less than the manufacturer requires you will be OK I am not sure how you would do this without some sort of mandrel tho. This plastic pipe gets pretty droopy if you just route the exhaust from the truck through it
353.24 Bends - How Made. Bends shall be so made that the conduit will not be damaged and the internal diameter of the conduit will not be effectively reduced. Bends shall be permitted to be made manually without auxiliary equipment, and the radius of the curve to the centerline of such bends shall not be less than shown in Table 354.24. For conduits of metric designators 129 and 155 (trade sizes 5 and 6) the allowable radii of bends shall be in accordance with specifications provided by the manufacturer
Pipe, Conduit and Innerduct for Underground Utilities
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They make adapters to put long sweep 90's on which I suggested. The designer told me they do it all the time in 42 inches. But I've found out can't be done. This raceway is for 13.8 HV which in itself requires larger bend for the cable. Just wondered how other have handled something like this. Thanks for your time guys. Always nice to get others input.
As I said earlier the only way I can see this without kinking the raceway is to heat it and bend it around a mandrel. Granted this usually happens with PVC. I looked at the job going on at the end of my street and they are just brute forcing the bends. This is utility work by contractors so I doubt anyone is really inspecting it. The wire was already in the pipe when they make that final turn up. That is not unusual for utility contractors. I watched them running service laterals a while ago and they were threading the wire in the joints of pipe as they went.