Sluice gate operating force 1

[Dennis59]

Does anyone have an opinion about the "real world" kind of forces involved in operating a sluice gate?
I am familiar with AWWA C560, Appendix A, and I can use that to come up with a number, but what about a 'stuck' sluice gate?
If I have a concrete corbel holding a sluice gate stand and the disc is corroded or jammed, I think the force of the operator could be much higher than AWWA calculates. And if something is going to break, I don't want it to be my concrete corbel...
Would most of you design for the breaking strength of the operator, or would you consider that to be too conservative?

Any thoughts would be appreciated.

p.s. I have seen some sluice gate operators in old wastewater plants where the anchor bolts of the cast iron wall brackets are coming out of the concrete due to ~some~ kind of overload situation (op possibly due to undersized anchors to start with?)

 

[JedClampett]

A very good and misunderstood question.
We design a lot of supports for sluice gates. If you look through the gate manufacturer's literature, there's usually a tab where they match the gate size and maximum head to an operator. Then for each operator there's a force that the operator can develop. Where you get into trouble is when you use the forces from the gate operators without adjusting them. This force is always based on a 40 lb force on the crank. Any operator can push with more than 40 pounds of force and some of those yahoos can really crank them, especially when the gate is jammed. Use a 100 lb force (multiply the force by 2.5). And don't forget that what comes up also goes down. They same force might be used to close the gate, reversing the load.
And by the way, the gate manufacturers will make the same mistake when they design an operator support.

 

[cvg]

give a maintenance guy a pipe or cheater bar and they can literally apply 100's of pounds of force on something designed for hand operation only. I have seen a contractor use a 6 foot cheater bar on a torque wrench with force applied by a backhoe just to tighten the bolts on a 36 inch flanged pipe fitting! When I questioned the safety and sensibility of his method of plumbing - he couldn't figure out what my problem was. I suggested that perhaps, the flanges, bolts or gaskets were not manufactured correctly and needed to be removed and replaced...

Better to be conservative on this design.