Painter's Ring Inside Water Tank

[Tank Man]

I have a request for a painter's ring inside a water tank water tank for a municipality. A specification has not been provided and I cannot find information on painter's rings, dimensions, mounting, etc. Miller/Honeywell has a painter's trolley (part#9059-1) that requires a 1 1/2" diameter rail (ring) mounted inside the tank. However, their manual provides no information concerning the throat dimensions of the trolley so that the rail supports can be designed. I have contacted Honeywell's support who seems to be totally oblivious to the need for a drawing that clearly depicts the throat dimensions. Does anyone have a drawing of a painter's rail/and support inside a tank that could be forwarded? We would modify the design to fit our needs and perform our own calculations based on the design. If another technical source is available, please let me know. I appreciate the help!

 

[JStephen]

Internal painter's rails were common in the olden days, not so much anymore.
Numerous small trolleys are available with nominal capacity and geometry adequate for the usage, but most of them say "Not for lifting people". It may be in the sales literature, or you might have to hunt through the instructions, but it is still usually there.
There are one or two fall-protection units with similar disclaimers, they are for fall-protection, not for lifting people.
Note that this probably relates to insurance and liability, not to the physical design or strength of the units.
The ones we were able to locate had 300 lb capacity (I see yours says 400 lb), but the intent was to use them for one end of a pickboard with multiple people, so that's not enough capacity to be useful.
If there is a painter's rail in a tank, it is necessary to inspect it prior to use, and then necessary to paint the rail itself. And most painters that do tanks are geared up to do so whether that rail is there or not. So putting one in may actually be a detriment to future work rather than a benefit.
On the rails we've done in the past, I think we've used flat bar, beams rolled the easy way, and round bar or pipe, depending on the specification and/or the trolley requirements, with supports as needed. On rafter-type roofs, typically a support every rafter.
If possible, confirm trolley type with the people that will actually be using it, also confirm spacing from the shell.
Roof couplings may be more practical, although less convenient to actually use.