Cylinder and Ram Assembly. - TM-55-1730-208-130006

TM 55-1730-208.-13

1-8. Hose.

c. Safety Relief Valve (No. 2). The safety relief

valve is self-contained and is also located in the

The hose connects at the discharge port of the

submerged end of the pump. This safety relief valve

pump assembly and inlet port of the cylinder and ram

provides an additional safety feature, its function is to

assembly. The flexible hose is provided to transfer

bypass hydraulic fluid to the reservoir when excessive

hydraulic fluid, under pressure (2235 psi), during raising

pressure is encountered inside the cylinder and ram

operations and to return hydraulic fluid during lowering

assembly.

A sudden load increase or thermal

operations.

expansion of the hydraulic fluid will cause the safety

relief valve to open.

1-9. Foot Assemblies.

d. Intake and Discharge Valves. The intake and

discharge valves consist of two balls and two springs

Each foot assembly consists of a caster, caster

assembled in tandem in the pump passage between the

mount, and caster arm assembly. The three foot

intake port and pump cylinder. The intake valve is the

assemblies mount on the leg, or leg extension, of the

first valve in the pump passage and permits hydraulic

tripod assembly for ease of movement and to prevent

fluid to be drawn from the reservoir into the pump

the hydraulic jack from shifting.

cylinder. The discharge valve is the second valve in the

pump passage and permits hydraulic fluid, under

1-10. Tripod Assembly,

pressure (2235 psi), to pass from the pump cylinder to

the cylinder and ram assembly.

The tripod assembly is the mounting base for the

cylinder and ram assembly.

The tripod assembly

e. Release

Assembly

and

Associated

consists of three tubular legs, four sets of three leg

Components. The release assembly and associated

extensions, five sets of six braces, six brace links, and

components are located near the pump mounting flange

one tension bar. By adding or removing leg extension,

at the right-hand side of the pump handle socket. The

the hydraulic jack may be assembled to any one of five

release assembly controls the raising and lowering of

basic closed heights configurations.

the cylinder and ram assembly ram.

1-11. Identification.

1-7. Cylinder and Ram Assembly.

The identification nameplate is located between

The cylinder and ram assembly consists basically

two attachment lugs at the top of the cylinder and ram

of an outer cylinder and inner ram with extension screw.

assembly. The assembly decal is centered on the

The cylinder mounts on the tripod assembly to form the

cylinder of the cylinder and ram assembly. A capacity

upper part of the hydraulic jack. The ram contains one

decal is located on the side of the pump assembly. '-'he

longitudinal and one spiral groove extending from the

instruction decal is located on the top of the pump

top of the ram to the top of the upper bearing ring. The

assembly near the air vent.

ram is guided during raising and lowering operations by

(See figure 1-2,)

a key in the ram upper bearing. A ram lock nut

assembly rotates downward on the spiral groove of the

1-12. Leading Particulars.

ram as the ram is being raised. The ram lock nut

assembly is provided to afford protection to personnel

Refer to table 1-1 for leading particulars.

and equipment in event of hydraulic failure or slipping of

load. An 18-inch extension screw is housed inside the

1-13. Differences in Models.

ram and may be manually raised to take up clearance

between closed height of the hydraulic jack and

This manual covers only the hydraulic jack, part

airplane.

number 50J25178 (type B6). No known differences

exist for the design covered by this manual.

WARNING

Do not extend extension screw

1-14. Painting Requirements.

more than 18 inches.

Paint tripod assembly in accordance with TM 55-

1500-204-25 / I.

1-3