Users of Superbolt/Supernuts 2

[newc]

Anyone have superbolt's supernuts on their applications and had difficulty removing them? Anyone consider using hydraulic nuts as an alternative?

 

[unclesyd]

We have used SuperBolts, SuperStuds, and SuperNuts beginning with the SuperNuts since the mid 80's. We had one incidence that I'm aware of where there was problem on a 2" SuperNuts where the removal instructions weren't followed. In discussions I’ve had with fellow users this is the main problem with the Supers, that is they have to be unloaded using the prescribed procedure.
One other problem I heard of that some people want to over torque the jack screws based on their intuition of the prescribed torque not being enough.

 

[smckennz]

We have used superbolts for joining girth gears on ball mills. No hassles; good things. But a little slow to tension and release.
For bolted connections that we need to break in a hurry, we use overlength studs and a hydraulic stud tensioner. It grips the stud end threads and stretches it; then the nut is run down by hand.
Hydraulic nuts look expensive,and the seals would be a worry. But I am sure they have their niche.

Cheers

Steve

 

[dfurey]

Hi, We have used superbolts for our C&E marine boilers currently used on the big deck Amphibs (LHA/LHD only on two ships). The waterdrum has a large dia. enclosure plate that is used to remove the Desuperheater for maintenance. The process to remove and install the door normally takes two shift and a torque multiplier (a real pain in the ass). The use of superbolts reduced this to just several hours, this saved maintenace dollars and decreased down time. There is a set prcedure to use when you plan to remove the bolt. The manufacturer recommends that a penitrating oil be srpayed on the fastener while still hot/warm, this will prevent damage to the small jack bolts when removed. Additionaly they recommend an anti-seize compound suitable for very high loads be used when installing. I can tell you first hand, if you do not keep the superbolts clean and dry (rust free) you will end up cutting them off.