Riser clamp torque

Old 08-22-20, 05:41 AM
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Riser clamp torque

I have a few holes developing in a my 70 year old cast stack.

I will cut out a section and replace it with PVC but will need to install a riser clamp above the cut.

How tight should the bolts on the riser clamp be to secure the pipe but not risk cracking the old cast?

thank you,
Old 08-22-20, 11:47 PM
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I don't know if there's a setting for a torque wrench. I make them tight. If the riser clamp damages the cast, it's ready for replacement anyway. I don't mean to sound flippant but that's the best I can do.
Old 08-23-20, 06:14 AM
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This is a Fernco style fitting?

Make sure the joint is clean, lightly torque you can always add more torque if needed!
Old 08-23-20, 05:20 PM
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Thanks Steve,


No, a Fernco is 60 ft/pd, I can not find one manufacture that states a recommended torque for the bolts, so I guess Steve is right, just tighten until it "feels right"........and the pipe doesn't slip!
Old 08-24-20, 10:14 AM
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I did find a torque spec for one brand of riser clamps. For 4", it has a torque spec of 46lbs.

If possible, see if you can a riser clamp on a fitting above too just below a hub. It's obviously not always possible, but ensures that nothing will slip!

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