Tri State Hydraulics




Assembly drawing shall be provided.
A. Dimensions, mounting characteristics, and specifications shall be clearly identified.
B. Arrangement of components shall be shown on sectioned drawings.
a. Catalogue illustrations shall be applicable.
C. Components shall be clearly identified.

2. Parts lists describing components shall be provided.
A. Components shall be clearly identified.
B. Components shall be traceable to respective drawing & catalogue illustrations.

3. Name plates shall be provided.
A. The following information shall be permanently indicated:
a. Manufacturer's name & address
b. Model number
c. Serial number
d. Bore & Stroke

4. Cylinders shall be proof tested at the factory.

5. Ports shall be plugged for shipping.


1. Cylinders shall be securely anchored according to mounting characteristics.

2. Cylinders shall be properly aligned with operating mechanisms.
A. Side loads shall be avoided.
B. Piston rods shall not rotate in non-rotating cylinders.

3. Extreme care shall be exercised to protect mounting surfaces, threaded connections, and exposed piston rod from damage.

4. Piping shall be as direct as possible.
A. Avoid sharp bends & fittings wherever possible.
B. Support piping to prevent vibration.
C. Port connections shall be accessible for maintenance.

5. Cleanliness is extremely important.All piping & system components shall be cleaned & flushed before connecting cylinder.
A. Protect cylinders from contamination by filters, strainers, and magnets that limit particle size to 25 micron or less.

6. Exercise all possible caution when beginning initial operating of cylinders.
A. Begin with slow speeds, low pressures, and “work up” to operating levels.


1. Servicing will be necessary periodically,
A. Dynamic seals are subject to wear.

2. Failure of dynamic piston rod seals will be noted by excessive leakage.
A. A “wet” condition is normal.

3. Failure of dynamic piston rod seals will be noted by excessive leakage.
A. Piston seals can be checked by applying pressure & disconnecting port at opposite end.
a. Elastomer type seals should not bypass.
b. Metallic sealing rings will bypass. Six (6)oz./min. is not uncommon for large bore cylinders.

4. Other components subject to wear are rod bushings, packing glands, and cushion rings.
A. Installation should be checked for adverse load conditions if components show excessive wear.
a. Clearances between piston rod, rod bushing, and packing gland allow a sliding fit.
b. Cushion rings are custom-fitted for a slip.

5. Dynamic piston rod seals can be replaced without dismounting cylinder.
A. Disconnect piston rod end & "clear."
B. Remove packing gland screws.
C. Remove packing gland.
a. Use mallet or prying tool to loosen & disengage.
D. Remove sealing rings.
a. Exercise care to avoid scratching, nicking, or otherwise damaging sealing ring bore & piston rod.
E. Thoroughly clean seal housing bore.
a. Check rod bushing & piston rod for excessive wear or other damage.
b. If either rod bushing or piston rod is defective, dismount cylinder for repair.
F. New sealing rings are installed by slipping them over rod end.
a. Install soft sealing rings first (inboard).
b. Install hard sealing rings last (outboard).
c. Exercise care to install rings with sealing lips toward pressure.
d. Grease rings & housing bore to facilitate assembly. Use only grease compatible with system fluid.
G. Refit packing gland with new rod wiper before replacing.
a. Rod wiper is retained in packing gland with retaining ring.
b. Rod wiper can be replaced with packing gland assembled; however, it is more easily accomplished with packing gland removed.
H. Reassemble packing gland & securely tighten screws.
a. Packing gland shall be tight against housing.
b. Measure clearance & shim accordingly.
c. Excessive pressure by packing gland on sealing rings will cause rapid wear.
d. Failure to securely tighten screws will result in packing gland failure.

6. Cushion valves are replaced with new units when found defective.
A. Cushion valves are adjusted at factory.
B. Cushion valves can be readjusted to suit operating requirements.
a. Loosen locknut & turn adjusting screw with an allen wrench to suit.
b. Locknut shall be securely tightened after adjusting. Hold adjusting screw when tightening locknut.

7. Cylinders shall be dismounted for servicing or repair work other than replacing piston rod seals & rod wiper or cushion valves.
A. Servicing repair work shall be performed only in a recognized maintenance area.
B. Maintenance area shall be properly equipped to perform work.

8. Removing or replacing piston rod assembly.
A. Exercise care to maintain piston rod in alignment with axis of cylinder to prevent "scoring" body.
B. Metal piston sealing rings will require compression to allow assembly.
a. Wrap wire around sealing rings & pull ends tight to compress ring for assembly.

9. Body & piston rod shall be carefully inspected when dismantled.
A. Body I.D. & piston rod O.D. surfaces shall be 16 RMS or better.
B. Both body I.D. & piston rod O.D. surfaces subject to dynamic sealing shall be free of tool marks, scratches, pits, nicks, or other defects.
C. Do not use defective components.

10. Static seals shall be replaced when disturbed by dismantling.
A. Static seals are easily "pinched & cut" during assembly.
a. Exercise care to avoid damage.
B. Static seal back-up rings shall be installed outboard with static seal toward pressure.

11. There is no set procedure used to dismantle or assemble cylinders.
A. Size, shape, weight, and other variations of componentswill dictate handling.
B. It is important that reasonable care be taken to avoid damaging components.
C. Cleanliness shall be observed at all times.


1. Spare parts & replacement parts shall be ordered from respective parts lists.
A. The cylinder Model Number, Serial Number, Part Number, and Description shall be provided for each parts order.
a. No parts can be furnished unless Model Number & Serial Number are clearly defined.
B. Spare part kits are available for most cylinders.
a. Kits include all packing & seals necessary to refurbish cylinders.