Underslung Monorail
Underslung Monorail
(OP)
Anyone ever do a 35 ton underslung monorail? What hardware was used to apply the load to the bottom flange of the S Section (I Section)? We have a client that wants to use such a critter...
Dik
Dik






RE: Underslung Monorail
I have worked on a few 25 Ton service hoists.
Not sure what you mean by "hardware was used to apply the load to the bottom flange.."
Usually its the trolley wheels.
RE: Underslung Monorail
There's a problem with heavy loaded underslung monorails in transferring the load to the bottom flange. I've not been involved with this high a load before, but I recall from earlier work that it was difficult sourcing the equipment to transfer the load to the beam.
Dik
RE: Underslung Monorail
You may consider a under running hoist on double girders.
RE: Underslung Monorail
You may need under running end carriages.
As I said, the best way may be to used two "monorail" beams each with an under-running end carriage and a small bridge spanning carriage to carriage to which the hoist can be mounted.
Essentially you wind up with a stationary inverted bridge crane with an under running trolley.
RE: Underslung Monorail
Assuming you can find a big enough I-section with thick enough flanges, and the beams can be supported and spliced properly for these kinds of trolley wheel loads; maybe consider two 20 ton trolleys on the same beam line, and spaced 2 - 3' apart. They are held together by an underslung trolley beam (parallel to the main I-beam) which is pinned to the two trolleys, and also a pin supports the lifting means (maybe this is just a thick stl. pl., triangular in shape, with high pin holes at the two trolleys, and a lower level pin hole for the lifting means).
You might also look at four Hilman rollers, which would replace the two trolleys and treat the beam flanges a bit more kindly, since they distribute the loads over a number of points and a longer flange length than a single wheel. They could be made to work on a flat flange surface as on a WF beam. Then design your own complete trolley system around these rollers. They will require more longitudinal force to move them down the rail. What does move this system up and down the rail length, straight or curved?
You might also look at 'cam followers' which would mount on trolley side plates, of your own design. These can run on a sloped or flat flange top surface, or run on hardened bar stock attached to the top of the bottom flanges. And, can be designed to apply their load fairly near the beam web.
RE: Underslung Monorail
RE: Underslung Monorail
Can you describe the 'cam followers' a bit more? I'm having difficulty understanding how they function.
I will take a look at Hilman rollers.
thanks, Dik
RE: Underslung Monorail
Google any roller bearing manufacturer (RBC, Timken, SKF, Torrington), and then look for cam followers or cam rollers. Try 'RBC Roller Bearings', click products, then cam followers, and look at their brochure. I found this pretty easily and it shows some of what you need to see and study a bit. Look down at page 40 and beyond for some details and engineering/tech. info. Then ask way. I envision these running in tandem, four on a side, two on each side of the beam on the front trolley, connected to that trolley's side plates (kind of a walking beam). Same for a rear trolley, and connect the two trolleys with a beam (yoke) which holds the lifting device.
What are they doing with this? Is it just a short, straight, move from one work station to another? How is it powered for this linear motion? How are you supporting the trolley beam and how big does it have to be? Flange bending as a supported cantilever off the beam web is the killer, and the flange tips at beam splices are really difficult.
RE: Underslung Monorail
While checking for the current CMAA manual for a much smaller monorail I came across some software that might be of interest. In case you have not seen it, this might be of interest. I tried this out and it is fairly handy.
http://www.ezsdc.com/software1.aspx
Brad
RE: Underslung Monorail
If it comes to that, I work very closely with a company that does custom work of this nature.
RE: Underslung Monorail
Thanks, Brad... I have my own excel sheets for design, but not including flange loads.
Dik
RE: Underslung Monorail
Dik
RE: Underslung Monorail
Give them a ring.
RE: Underslung Monorail
Dik
RE: Underslung Monorail
I suppose anything can be done. Just a matter of how much the customer wants to pay.
Do you mind my asking what the monorail is for?
RE: Underslung Monorail
You may be able to use load distribution by increading number of wheels on the bottom flange to be able to take the load. But increase of the number of wheels will require some space engagement under the trolley beam and restricts the travel in curvatures.
I saw some catalogs almost ten years ago that gives special sections for trolleys with increased flange and web thicknesses. I cannot remember the name right now but the manufacturer was from the North America.
Of course the best is to use two traveling beam for large loads, and loads on the beams as suggested above.
Kind regards,
Ibrahim Demir
RE: Underslung Monorail
Dik
RE: Underslung Monorail
brad