| Several types of jacks were on the repair locker hull
allowance. The purpose of the jack was to move extremely heavy
equipment or other objects over relatively short distances.
The hydraulic jack was extremely powerful and could lift ten
tons, much more weight than a block and tackle or chain falls;
however, it could not lift weight very far. In some cases,
additional equipment was required and used in tandem, such as
lift and push or pull jacks with a block and tackle or chain
falls.
Its shape was more conventional than the push and pull screw
jack. It had an 8-inch by 30-pound steel rectangular plate base
and a hydraulic telescopic tube called a ram. The ram was
controlled by hydraulic fluid inside the jack. A lever and
handle at the base of the jack pumped the ram upward, and a
screw on the opposite side, when turned open, released the
pressure and let the ram down. |
