Underslung Monorail 4

[dik]

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

 

[ToadJones]

That would be a very large 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.

 

[dik]

Thanks TJ...

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

 

[ToadJones]

Yea- I'm not sure you'll find a packaged hoist with a 35 Ton capacity for a monorail.
You may consider a under running hoist on double girders.

 

[ToadJones]

We have had to design similar devices and there are ways to do it.
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.

 

[dhengr]

Dik:

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.

 

[ToadJones]

You may find an under running end carriage that would typically be used on an under running bridge crane to accomplish much of what Dhengr is describing when he says "...They are held together by an underslung trolley beam (parallel to the main I-beam)..."

 

[dik]

dhengr:
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

 

[dhengr]

Dik:

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.

 

[Brad805]

It sounds to me like you may need a custom rail and trolley from someone like Kone.

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

 

[ToadJones]

Dik-
If it comes to that, I work very closely with a company that does custom work of this nature.

 

[dik]

Thanks, Toad... I've forwarded this thread to the project engineer for this component of the work.

Thanks, Brad... I have my own excel sheets for design, but not including flange loads.

Dik

 

[dik]

Toad... do you think 35 tons is 'do able' for an underslung monorail?

Dik

 

[apsix]

Kone CXT hoists are listed for a SWL of 32000 kilograms, which is just on 35 short tons by my calculation.
Give them a ring.

 

[dik]

Thanks,

Dik

 

[ToadJones]

In the traditional sense of a "monorail" it is definitely pushing the envelope.
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?

 

[saplanti]

In case the beam capacity is sufficient, the thickness of the flange and web within the code requirement by using the required number of wheels splitted from each other not to combine their local effects, it can be done.

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

 

[dik]

I'll confirm the use, but, I think it's for moving heavy equipment related to the mining industry.

Dik

 

[Brad805]

If you do get to figure this out be sure to show us what you come up with. I am interested to see the size of flange and trolley to support that weight. These mining guys come up with the neatest problems. We have been involved in lifting devices to fix mining items and things get big.

brad