Usage:
 |
To prevent possible personal injury, be sure the engine has been stopped for a minimum of five minutes. Make sure all pressure in the system is released before any lines are disconnected. |
 |
1. Disconnect hose (4) from accumulator (2).
2. Fasten a hoist and tooling (A) to accumulator (2). Remove the bolts and clamps (1) and (3). Remove the accumulator from the machine. The weight of the accumulator is 554 kg (1225 lb).
NOTE: The following steps are for installation of the steering accumulator.
3. Fasten a hoist and tooling (A) to accumulator (2). Put the accumulator in position, and install clamps (1) and (3).
4. Connect hose (4) to the accumulator.
Disassemble & Assemble Steering Accumulator
Start By:
a. remove steering accumulator
1. Remove valve guard (1) and dynaseal (2) from the accumulator.
2. Use a valve core tool to release gas precharge pressure from the accumulator bladder. Remove valve core (3).
3. Detach bladder from gas end plug by unscrewing nut (4).
4. Remove large diameter locknut (5) located externally on the gas end plug.
5. Remove exposed spacer (6).
6. Push the plug assembly complete with bladder into the shell.
7. Remove O-ring (7) and washer (8).
8. Fold and remove anti-extrusion ring (9).
9. Remove plug assembly (10) and bladder (11) from the shell.
10. Repeat Steps 4 through 8 to remove the valve assembly at the other end of the accumulator shell.
Cleaning and Inspection
a. After disassembly, clean all parts with an approved cleaning solution such as Hydrosolv 4165 (8T7570) [available in U.S. and Canada only through the Caterpillar parts system or your nearest Caterpillar dealer in 208L (55 U.S. Gal.) drum.
b. Blow all parts dry with air and place them where they will be free from dirt or other foreign material.
c. Check bladder, O-ring, seal and anti-extrusion ring for deterioration, abrasion marks, cracks, holes or any similar defects. Replace as necessary.
|
To prevent possible personal injury or damage to the bladder, do not overinflate the bladder outside of the shell. |
|
d. New or used bladders must be checked for leakage by inflating to normal size [21 kPa (3 psi) maximum]. Use a soapy solution to check the bladder for leaks. If a leak is detected, the bladder must be replaced with a new bladder. After testing, deflate the bladder immediately.
NOTE: The following steps are for the assembly of the steering accumulator.
11. Pour a liberal amount (up to 10% of volume) of clean hydraulic fluid into the shell to lubricate and cushion the bladder.
12. Remove all air from the bladder and fold lengthwise into a compact roll. Install the valve core to retain this condition.
13. Insert bladder (11) into the shell.
14. Insert gas end plug (10).
15. Fold anti-extrusion ring (9), pass through top opening in shell and place in position internally with steel collar at shell mouth.
16. Replace washer (8) and O-ring (7).
17. Pull up on the bladder to bring the valve stem through the center of the gas end plug.
18. Install spacer (6).
19. Secure with valve stem nut (4) but do not tighten.
20. Secure gas end plug with large locknut (5).
21. Connect hose to pressure regulator on nitrogen cylinder. Use "dry nitrogen" only.
|
Dry nitrogen is the only gas approved for use in the accumulator. Charging the accumulator with oxygen gas will cause explosion. This danger will not happen if nitrogen cylinders with standard CGA (Compressed Gas Association, Inc.) number 580 connections are used. When you order nitrogen gas, be sure that the cylinders are equipped with CGA No. 580 Connections. Do not use color codes or other methods of identification to tell the difference between nitrogen and oxygen cylinders. |
|
22. Install tool (B) on the valve of the accumulator. Connect swivel connector of the hose assembly to the valve extension.
| NOTICE |
|---|
Charging the accumulator too rapidly can cause the bladder to rupture. Set regulator to 69 kPa (10 psi) charge only. |
23. Precharge the bladder slowly to approximately 69 kPa (10 psi) before completely tightening the valve stem nut.
The following chart shows the charging pressure and temperature relationship for the 9600 kPa (1400 psi) accumulator.
24. Continue to inflate the accumulator to 9600 kPa (1400 psi) by slowly opening the pressure regulator valve on the nitrogen cylinder. Close it occasionally to allow needle on the pressure gauge to stabilize. This gives an accurate reading of the precharge pressure. When the correct precharge has been reached, close pressure regulator valve on nitrogen cylinder securely.
25. The bleeder valve can be used to let out any gas pressure in excess of desired precharge.
26. Replace seal (2) and valve guard (1).
- End By:
a. install steering accumulator.