Hydraulic Cylinder Testing

TM 5-5420-205-14

cylinder on a horizontal position with ports face up. The

6-3. Hydraulic Cylinder Testing

piston shall be unrestrained and cycled not less than 12

a. General. Following repair, hydraulic cylinders

times to purge system of air.

shall be tested as described below. The tests should be

(2) Insert cylinder in a suitable test frame or fixture

conducted at an ambient air temperature of from plus 40 .

so that piston is restrained from bearing against either

to plus 90 . and a hydraulic fluid temperature of plus

cylinder head.

40 . to plus 150 . at the pump discharge.

(3) Insert a graduated transparent tube of either

NOTE

plastic or glass, and fasten it vertically to the cap-end

Hydraulic oil conforming to MIL-L-10295 shall be

cylinder port in such a manner as to prevent leakage. One

used. and tests conducted in the order specified.

end of the tube shall be open to atmosphere temperature.

b. Curbing. Rotation, and Pinning Cylinders Proof

(4) Apply a 3,000 psi fluid pressure and maintain

Pressure.

this pressure in the cylinder at rod end. Allow fluid

(1) Cycle each cylinder with the piston

bypassing piston to enter and collect in the vertical tube.

unrestrained through not less than five complete cycles to

(5) Measure rise of fluid level during a period of

demonstrate operation, stroke, and adjustment.

not less than three minutes to determine the rate of internal

(2) Place each cylinder in a suitable test frame so

leakage.

that the cylinder piston is restrained from bearing against

(6) Repeat the test on the other side of the

either cylinder head.

cylinder after reversing the pressurized and plugged ports.

(3) Connect the rod-end port and the cap-end port

(7) Internal leakage rate past the piston at 3,500

of cylinder to a common hydraulic line so that both ends of

psi for rotation, curbing, and pinning cylinders shall not

cylinder will be pressurized simultaneously.

exceed three fluid ounces per minute, using MIL-L-10295

(4) Apply a hydraulic proof pressure of 7,000 psi to

hydraulic oil.

cylinder for five minutes.

(8) Leakage in excess of the above rates

(5) Evidence of leakage, damage, or inability to

constitutes failure of this test.

cycle as required, shall constitute failure of this test.

e. Unfolding Cylinder Internal Leakage.

c. Unfolding Cylinder Proof Pressure.

(1) Test each unfolding cylinder as in d above,

(1) Cycle each cylinder with piston unrestrained

except that the rate of leakage shall be measured from one

through not less than five complete cycles to demonstrate

end of the cylinder only.

operation, stroke, and adjustment.

(2) Apply an 8,000 psi pressure at the rod-end

(2) Place each cylinder on a suitable test frame,

port, and permit hydraulic fluid passing the pressurized

so that cylinder piston is restrained from bearing against

piston to collect in a tube inserted in the cap-end port.

either cylinder head.

(3) The rate of internal leakage past the piston at

(3) Connect rod-end port and cap-end port of

8,000 psi shall not exceed 8 fluid ounces

cylinder to a common hydraulic line so that both ends of

per minute, using MIL-L-10295 hydraulic oil.

cylinder will be pressurized simultaneously.

6-4. Fabrication of Hydraulic Lines

(4) Apply hydraulic proof pressure of 12,000 psi to

For fabrication of hydraulic lines using high pressure tubing

cylinder for five minutes.

and fittings, refer to TM 5-5420-204-12, Appendix B, for

(5) Evidence of leakage, damage, or inability

superstructure model nos. 2195-1 and 2195-2; refer to TM

to cycle as required, constitutes failure of this test.

5-5420-210-12, Appendix C, for model nos. 2271 and

d. Curbing, Rotating, and Pinning Cylinders Internal

2272.

Leakage.

(1) Connect each curbing, rotating, and pinning

cylinder to a hydraulic system and place

Section II. ELECTRICAL SYSTEM CABLE ASSEMBLY REPAIR

The intercom cabling starts with a quick-disconnect

6-5. General

coupling at the base of the rotation cylinder on the

The wiring harness of the end bays (model nos. 2195-2 and

transporter deck. The cabling is then routed through a

2271), and interior bays (model nos. 2195-1 and 2272)

flexible metal conduit to the junction box. The junction box

consists of an intercom cable, connectors and mounting

contains a wye connection in interior bay model no. 2195-

hardware as shown in figure 4-17, 4-18(1) and 4-18(2).

1, and a terminal board in interior bay model

6-6