the equivalent torque in the crane

please can tell me the formulae by what i can calculate the equivalent torque in order to calculate afterward equivalent capacity and make a choice for an adequate motor,
and that in the case of crane.
thank you in advance.

 

[quark]

Possibly it is the weight of the item to be lifted multiplied by the height of the crane from the ground in corresponding units.

Regards,

 

[quark]

Oops! Iam wrong. Take the diameter of the drum.