Commercially available shaft anti-rotation/lock device 1

[geesamand]

I have some gear-driven machinery where the customer will only perform maintenance when the unit is unable to rotate. The impeller end of this machinery cannot be taken out of the process flow and so it tends to rotate in either direction after de-powering it. Is there a proven product that could be installed to mechanically lock the equipment from rotating during maintenance work? I think I prefer something with spline engagement, cross-key, cross-pin, etc instead of a friction brake.

I have some access to a section of this shaft along its length and/or connect to one end. Shaft size is 2" to 5" diameter.

 

[dvd]

Certainly made several for lockout purposes over the years. I recall working out a vernier-type circular arrangement that would allow pinning over a range of shaft positions.

I am aware of this product by Welker -

http://www.welkerproducts.com/pdf/DS3_CATALOG_rev10-17-17.pdf

They would probably work with you on a custom arrangement.

B- or C- sprocket with pinning holes bored in the plate would be a quick commercial part adaptation. Ringfeder-type shaft locking device would allow installation on a shaft without adding keyway. You would need to fabricate a fixed clevis type of bracket for the locking pin to react to. Of course, a good design would interface with a proximity switch that indicated the lockout pin was safely removed prior to restart.

 

[geesamand]

I like that Welker design - but I suspect my customer won't want to invest in the actuated operation.

I had considered how one might form a safe interlock against energizing the motor against the stop device. Aside from making it large, bright, and obvious, I can make sure it will withstand motor startup torque.

 

[MintJulep]

A sprocket on the shaft and a roller chain anchored to "ground" would do the job.

Applying it to a shaft that "might move" poses some hazards.

Your customer's safety department needs to be involved in this design.

 

[EdStainless]

We had a manual version of one like the Welker, it used a lever to insert and retract the pin.
Ours had switches at both ends, positive lock and full release. They were ties into the motor controls.
In fact ours also had provision for a padlock to lock it in place.

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P.E. Metallurgy

 

[geesamand]

We will need to interface with the customer's safety team. It is their prerogative to work on machinery while the process side remains in motion, and this expectation appeared long after we designed and sold the equipment.

Right now I'm trying to see what is practical on the mechanical side. I will have some opportunity to off-load responsibility (or request specifics) as it relates to ensuring a safe lock-out-tag-out system, etc.