Quote Originally Posted by tonyfoale View Post
The 1.5 - 2 ton is at the end of the boom. The actuation is way back from that and so through leverage you need several times 1.5 - 2 ton at the actuator to get 1.5 - 2 ton at the hook. Using a 3000 lbf actuator may give you a useful tool but it will not give you 3000 lbf where it matters.
A one good thing about linear actuators/ screw jacks, is that they are oil-leak free. I have 3 oil leaking hydraulic jacks on my repair shelf. There are screw jacks with a capacity of up to 200 ton, and travel length of 3.5 meter/ 138 inch. Screw jacks are often custom-made to meet specific application needs.