hydraulic cylinder size for b7100 lift

[ohiokubota]

I am trying to figure out about how long the lift cylinder is on a b7100 FEL > i was looking them up new and they say 2x30x1.25 is that closed or all the way open i am not trying to buy a cylinder if it is the wrong one. i was looking at the cylinder on this web page below

https://www.surpluscenter.com/item.asp?UID=2009081820012556&item=9-7476&catname=hydraulic

thanks

 

[J_J]

I am trying to figure out about how long the lift cylinder is on a b7100 FEL > i was looking them up new and they say 2x30x1.25 is that closed or all the way open i am not trying to buy a cylinder if it is the wrong one. i was looking at the cylinder on this web page below

https://www.surpluscenter.com/item.asp?UID=2009081820012556&item=9-7476&catname=hydraulic

thanks

The figures you stated is the bore and stroke. The closed/retracted length is 40 1/4 in, from pin to pin. The extended length would be 70 1/4 in.

 

[Leejohn]

Are you sure your cyls. are 2" bore? That is a lot of cyl for a b7100. You sure don't need them that big. Might start braking things.

 

[jas67]

Are you sure your cyls. are 2" bore? That is a lot of cyl for a b7100. You sure don't need them that big. Might start braking things.

It would be too slow too.
If the OD of the cyliner is 2", the it has a bore of 1.5 or 1.75 depending on wall thickness.

 

[ohiokubota]

well 2 inch is what the dealer said to get and then he told me he didnt know how long the travel to get. so now i am trying to figure it out i think 30 is a lil long for wat i am trying to do. And if 2 inch is to big what sizes should i be looking at because i am going to be building this loader myself at a machine shop

 

[J_J]

I would think a 2 in bore would be fine, as the rod is usually about 1.125 in . As to how long, you have to work out the geometry as to the angle to mount it and what the lift height will be. Maybe you can take some pictures of other tractors with loaders, and get some ideas. You could try and lay out the overall shape in wood, and use nails or screws as the pivot points. If you had a CAD program, and knew how to use it, you can figure out a lot of things with it. The angle that you mount the cylinders, will determine the lift capacity of the loader, taking into account the length of the arms, size of the bucket, etc. Then you have to decide, do you want one or two tilt cylinders.

a 2 in bore, and 1.125 shaft, at 5 GPM, would have an extend speed of 6.1 ipsx30 = 4.9 sec
-----------------------------------------------------retract speed of 9 ipsx30 = 3.3 sec

 

[J_J]

Push force on that cylinder would be 7,854 lbs
pull force---------------------------5,369
push at a 45 degree angle----------5,554
pull--------------------------------3,796

all the above data , figured at 2500 psi, and 5 GPM

 

[ohiokubota]

well i least want it to go over 60 inch over any standard truck bed. and i am only going to run one bucket cylinder i think a 2-24 should work. i was thinking in between 20 and a 24 but not sure. and for the cad program i think he has that at his shop i will half to ask him. i have thought about using wood but i have only 2 days to build this loader at his shop i can only do it on the weekends when there is no one there working. kubota said my tractor should hold 5gpm but no more than that or i will be pushing the tractor hydraulics to its limit.

 

[J_J]

You have to be careful that you do not make the bucket to large, and over load the front axle, and you might make the rear end light, and will always have to have some weight on it. 24 in stroke for the tilt seems long , but it depends how you mount it.

 

[ohiokubota]

the bucket is only be 4 feet long and 16 inch high and a 14 inchs deep. i am sorry i screwed that up i was talking about 20 or 24 inch lift cylinders and probably go with a 12 inch tilt i have a 350lbs weight for the 3 point