Six-sided fastener, internally threaded, used with a bolt to secure objects together.
What the hex nut does on a fire line, and how to specify it.
The hex nut is the internally threaded fastener that locks a bolt or rod in place. In a hanger assembly it is the part that takes up the load from the pipe and transfers it into the anchor. Six flat sides give a wrench a clean bearing, so it can be tightened to a firm, repeatable hold.
The nut has to match the thread of the bolt or rod it is used with, so specify it against the fastener rather than on its own. Pair it with the matching washer so the load is spread when it is tightened, and use the correct count so the clamp does not ride on a single nut.
Carbon steel, electro-galvanized, the same spec as the rest of the fastener line. The finish protects the thread, which is what a nut is made of, in the damp air fire rooms often hold.
Send the line with the rest of the assembly rather than as a single part. State the size against the pipe outside diameter it serves, the finish, and the count. Pair it with the matching threaded rod, nuts, washers and anchors from the same range, and flag whether the design needs the fire-rated, FM/UL marked version, so the support arrives with the pipe instead of chasing it later.
Against the bolt or rod thread it is used with, so the threads match. Add the matching washer and the correct count.
Carbon steel, electro-galvanized.
So the load is spread over a wider bearing surface when the nut is tightened, instead of concentrating on one point.
Selection guides and field notes on fire protection pipe, fittings and supports.
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Read →Send your bill of materials or drawing — we confirm spec, cert and lead time, then ship the full package.
