TM 9-243
TYPES AND USES - Continued
RATCHET LEVER JACKS
A vertical ratchet lever jack has
a rack bar that is raised or
lowered through a ratchet lever.
Some
are
equipped
with a
double socket, one for lowering,
one for raising. Others have
one
socket
and
have
an
automatic lowering feature.
An outrigger ratchet jack is ratchet operated and has an
extra reverse ratchet handle and a base plate.
HYDRAULIC JACKS
A hydraulic jack operates
through pressure applied to
one side of a hydraulic
cylinder which moves the
jack head. These jacks are
automatically
lowered
by
releasing the
pressure. Vertical hydraulic jacks come in a variety of
types, in capacities from 3 to 100 tons, having different
extended heights.
The automotive dolly jack is primarily used to lift
vehicles. It operates through a horizontally mounted
hydraulic cylinder (1) which is manually operated by the
pump handle (2) raising and lowering the saddle (3).
The jack design permits the saddle to remain parallel to
the base through its complete range of motion. The
saddle swivels and the frame is equipped with wheels
and casters for ease of positioning. Dolly Jacks range
from 2 to 20 Ton load capacity and have different lifting
heights.
A push-pull hydraulic jack consists of a pump (1) and
ram (2) connected by a hydraulic or oil
hose (3). These jacks are rated at 3, 7, 20, 30, and 100-
ton capacities and have many different applications
The push -pull hydraulic jacks are furnished with an
assortment of attachments that enable you to perform
countless pushing, pulling, lifting, pressing, bending,
spreading, and clamping operations. The pump is hand
operated. Simply turn the control valve (4) on the side of
the pump clockwise, stroke the hand lever (5) up and
down and the ram will extend. The flexible hydraulic or
oil hose allows you to operated the ram from a safe
distance in any desired position. Ram retracts
automatically
by
turning
the
control
valve
counterclockwise. The attachments can be threaded to
the end of the plunger, to the ram body, or into the ram
base.
Change 3 20-3
