Reader ghb624 found a few of these bolts in a storm-water drainage channel. At the time he wasn’t familiar with them but was intrigued by their shape and construction. After a bit of searching on some forums he came upon what sounds like their probable function.
Those are restraining bolts for ductile iron water main installation.
The fittings have a flange drilled for bolts. The plain pipe end has
a field installed flange (the brand show is called a Mega-lug) the
field installed flange has teeth which bite into the plain end of the
pipe. The bolt heads on these teeth shear off when the proper torque
The T-bolt looking things in the original post clamp the factory
flange on the fitting to the Mega-lug. The whole point is to resist
inertial forces from “blowing off” the fittings/hydrants/valves, etc.
Sounds good to us — after all, ghb624 found these in an area where such bolts might logically wind up. You just never know what you’ll run into slogging through a drainage ditch.
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