Chapter 2. OPERATING INSTRUCTIONS - TM-55-1730-213-120003

TM 55-1730-213-12

4. DESCRIPTION.

This manual contains overhaul instructions for the 12-Ton Fixed-Height Tripod Jack Assembly, manufactured by

Sancor, Inc., El Segundo, California, under part number 1214-151.

5. IDENTIFICATION.

The jack is an integral unit consisting of multiple extension ram and plungers, reservoir, hand pump, and three

tripod legs. Each leg is equipped with a spring-loaded caster to provide mobility when the jack is unloaded. As the load

is applied, the casters retract and permit the feet to take the load.

6. DIFFERENCE IN MODELS.

This manual covers only the 12-ton hydraulic tripod jack, P/N 1214-151. No known unit differences exist for the

model covered by this manual.

7. TABULATED DATA.

Working Pressure .................................. 2893 PSI

Manufacturer .........................................Sancor Inc.

Relief Pressure...................................... 3182 PSI

Part Number .........................................1214-151

Hydraulic Fluid

Load capacity ........................................12 tons

Above 28.9 C (-20F). .................... MIL-H-5606

Hydraulic Lift .........................................23 in.

Below 28.9 C (-20 ) 75% .............. MIL-H-5606

Screw Extension. ...................................3 in.

Plus Naptha 25%

Extended Height ...................................40 in.

Reservoir Capacity ................................ 1.7 Gal

Collapsed Height....................................14 in.

Weight Including Oil ............................. 207 lb.

CHAPTER 2

OPERATING INSTRUCTIONS

Section I. CONTROLS

10. VALVE BODY.

8. GENERAL.

The valve (11, figure 3), located at the lower front

This section furnishes the operator or crew with

sufficient information for proper operation of the tripod

side of the pump assembly (8), controls the return flow of

fluid from the cylinder and ram assembly. The valve

hydraulic jack.

must be closed to raise the ram. Opening the valve

allows fluid to flow from the cylinder to the reservoir,

9. FILLER AND VENT ASSEMBLY.

causing the ram to lower.

The air vent assembly (33, figure 2) located in the

11. HANDLE.

top of the reservoir (23) is provided to establish a zero

pressure condition in the reservoir during operation of the

The handle (1, figure 3), is actuated to give the

pump assembly, permitting a free flow of fluid. The air

pump piston the necessary reciprocating action required

vent must be closed when the jack is not in use to prevent

to force fluid into the cylinder and raise the ram.

fluid leakage and contamination of the fluid by dirt and

moisture.

Section II. OPERATION UNDER USUAL CONDITIONS

12. GENERAL.

b. Raising.

These instructions are intended for personnel

responsible for the operation of this equipment. It is

(1) Loosen air vent (33, figure 2) and tighten

essential the operator be able to perform every operation

valve (11, figure 3).

of which the tripod hydraulic jack is capable.

(2) Actuate handle (1) to raise load.

c. Lowering.

13. OPERATING DETAILS

(1) Slowly open valve (11, figure 3) until

a. Positioning. The ground surface under the jack

desired lowering rate of speed is obtained.

shall be level. If the ground is soft, a board shall be

(2) After ram is completely lowered, close air

placed under each foot. The jack shall be placed so that

vent assembly (33, figure 2), valve (11, figure 3), and

a line drawn through the center of two of the feet is

lower extension screw (15, figure 2).

parallel to the fuselage of the airplane or load to be lifted.