Sprocket and gear sizing coupled to ACME thread

[apMechE]

I need to size a chain and sprockets to pry apart roughly 50 ton. I am looking at using 4 - 2'' ACME screws (2 LH, 2 RH) driven in the center with a high torque hydraulic motor (capable of around 10000 in*lbs) coupled to two sprockets. I also want speed to be fairly controlled through the gear reduction, though limiting the flow rate can help solve that issue. If the driven sprocket could stay under 15'' that would also be ideal. From plugging in my number to a screw calculator found here...

http://www.amesweb.info/Screws/LeadScrewCalculationsAcmeThreads.aspx

My raise Torque is calculated to be around 5150 ft*lbs. Pardon my stupidity, though if the motor is coupled either by one chain or even coupled to one side which is then coupled to the other, it is still a single reduction correct? If the motor is capable of 10000 in*lbs my ratio needed is around 6.2 to 1 correct? How do you size a chain for this torque at low speeds, say 5 RPM? Would you need to step it up to more than a single strand of chain? Would it take double reduction or a potential gear reducer? Any advice/ guidance would be appreciated. Thanks.

 

[dvd]

I recommend not to stand under the load.

 

[tbuelna]

A sketch would be helpful. Based on your description, one potential issue I can see would be getting each pair of jack screws synchronized in both directions of rotation using chain & sprockets to balance the load equally.

 

[apMechE]

Pretty much trying to replicate this concept, though for a wider width paving pan that carries additional weight. Its a self supporting crown mechanism and more or less pries the pan apart raising the center and flexing a 3/8'' plate at the bottom. Kit is roughly 45k lbs, hanging from two points 412'' apart. I can move my moment up about 28'' max.