148 Section 3 Installation Copyright Goodheart-Willcox Co., Inc. Goodheart-Willcox Publisher Figure 10-14. Rigid metal conduit is threaded so that it can be attached to fittings and couplings. RMC RM RM RM C C C nipples ni ni ni pp pp le le e e s Conduiitdno Co Co Co Co Co Co Co o nd nd nd nd nd nd ui ui ui ui ui u u u t t t t bodiess bo bo b b b di di d d d es es es es es es es e Bushings Bu Bu sh sh h h h in n g g Locknuts Lo Lo ck k ck nu nu ts ts s Preformed Pr r P P ef o o m bends b nd s s Coupliingnl Co Co C C Co up li ng n PROCEDURE Threading d i n RMC with a Hand n d Threader 1. Clamp C l the conduit int n to a pipe vise. See Figure 10-15. . 2. 2 Place an appropriately pr sized pipe reamer m er inside the end d of the conduit. 3. Rotate the re r ea mer until all the burrs rr s a ar e removed from fr the inside of the co c on duit. 4. Remove ve any burrs from the outside ou ts of the condu d ui t with a fi le. fi (Continued) 5. Mount a threading d in die inside the head of a hand nd threader (manual pipe pe threader), , fo f ol lowing the manufacturer’s u instructions.t io 6. Add c cu tting oil to the end of f the th conduit to eas a se the cutting and prevent e tool wear. 7. Place P the threading die e s sq uarely on the end of the conduit. 8. Rotate the hand threader th while pressing its head toward the h e conduit. 9. The die will engage e the conduit and beg e gi n n cutting the h e threads. 10. Stop pushing pu the head and continue nu e rotating a ti the hand threader. Add d cutting cu oil to to the conduit after every few ew ro r ot ations. 11. . When the end of the conduit du t is i even with the back of the threader die, e sto st op the rotations. 12. Reverse the direction on of o f the hand threader to remove it from m the th conduit. 13. Clean off the threa th e ad s with a rag and ff remove the e conduit c on from the vise. CODE ALERT RMC Bushings Section 344.46 requires that bushings be used where a rigid metal conduit enters a box, fit- ting, or other enclosure to protect the wire from abrasion unless the design of the box, fitting, or enclosure is designed to provide such protection.