Lehigh JHD Manual

CATALOG: JHD-93
JHD CYLINDERS
INSTALLATION & OPERATING INSTRUCTIONS
REMEMBER . . . .
WHEN PERFORMANCE COUNTS
SPECIFY LEHIGH
LEHIGH FLUID POWER, INC.
1413 ROUTE 179
LAMBERTVILLE, NJ 08530
www.lehighfluidpower.com
609-397-3487 • FAX# 609-397-0932 ISSUE DATE 1993
800-257-9515 REVISED 7/05
SHOP ONLINE at www.airlinehyd.com
800-999-7378

JHD CYLINDERS
INSTALLATION AND OPERATING INSTRUCTIONS
LEHIGH FLUID POWER, INC.
1413 Route 179, Lambertville, NJ 08530
TEL: 800-257-9515
609-397-3487 FAX: 609-397-0932
www.lehighfluidpower.com
TABLE OF CONTENTS
.......................................................................................................................................Page
A. Installation ………………………………………………………………….. 1
B. Trouble Shooting …………………………………………………………… 1 & 2
1. Jerky Action ……………………………………………………………… 1
2. Air Leakage ….………………………………………………………….. 1 & 2
a. Loss of Power or No Power ..………………………………………… 1 & 2
b. Evident Leak at Rod Seal …..………………………………………… 2
c. Leak between the Cylinder Tube and End Caps (Heads) …………….. 2
2. Loud Metallic Impact Noise ………………………………………….… 2
C. General Rebuild Instructions ………………………………………………. 3 & 4
1. General Guidelines ………………………………………………………. 3
2. Piston & Rod Assembly w/Miracalube®Lubrication System ……………. 3
3. Final Assembly ………………………………………………………….. 4
D. “ED” Lock Screw - Cylinder Option ……………………………………….. 4
E. Caution Section ………..…………………………………………….………. 5
List of Typical Repair Kit Contents …………………………………………….. 6
Component Torque Chart ……………………………………………………….. 6
Figures 1, 2 and 3 ………………………………………………………………… 7 thru 9
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A. INSTALLATION: (Follow All Safety Lockout/Tagout Procedures)
The cylinder is shipped from the factory with the MIRACALUBE self-lubrication
system (filled at the factory at the time of assembly). It is not necessary to add
grease or other lubrication to the unit prior to installation.
The cylinder is shipped with protective caps in the ports. Do not remove these
caps until the piping is ready for installation. If the cylinder has been in storage
for an extended time, it is advisable to exercise the cylinder; i.e., flex the internal
seals by stroking the piston before installation. Insure the air line used is equipped
with suitable filters, pressure control and a water trap.
Alignment of the piston rod with the work is necessary for the cylinder to operate
satisfactorily and insure long seal and rod bearing life. Be sure all mounting
surfaces are clean, smooth, flat and in alignment. Before finish piping of the
cylinder, stroke the cylinder using the air line to check the mounting arrangement
for misalignment or binding of attached mechanisms. The piston rod should
extend and retract without any unsteady or jerky motion.
If the cylinder is equipped with cushions, adjust the cushion screws to produce the
desired effect for the load, speed and air line pressure to which the cylinders will
be subjected under normal operating conditions.
B. TROUBLE SHOOTING:
1. JERKY ACTION:
Check for misalignment. Look for a bent or scored piston rod. The rod
bushing may be damaged. Check the cylinder tube for dents or bumps.
Confirm that the air cylinder supply pressure and volume are adequate to
operate the cylinder under normal conditions.
2. AIR LEAKAGE:
a. Loss of Power or No Power:
1. Check the air pressure at the machine. Then check the operating
pressure at the control valve for the cylinder and check the line
pressure at the cylinder port(s).
2. Apply air pressure to one port of the cylinder and check for
escaping air from the opposite port or the exhaust port of the control
valve.
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Next attach a small hose with adaptors to the open cylinder port.
Immerse the end of the hose in water, leak detection fluid or soapy
water to simplify this test.
Excessive bubble stream coming from the hose indicates worn or
damaged piston seals or damaged cylinder tube. Both should be
replaced in order for the cylinder to develop full power.
b. Evident Leak at Rod Seal:
The rod bushing assembly may be replaced without disassembly of the
cylinder. Loosen and remove the “ED” (for rod bushing) locking screw if
present. Use a close fitting wrench to remove the rod bushing assembly
from the cylinder by turning counter-clockwise (Figures 2 and 3).
Check the rod seal condition and replace as required. The rod seal is found
at the bottom of the now visible counterbore (Figure 3).
c. Leak between the Cylinder Tube and End Caps (Heads):
Tighten the tie rods to the torque specified in the table on page 6. Be sure
the Open and Closed Heads are properly squared to each other. Check for
the cylinder tube being seated in the tube groove in the face of each head
(Figure 3).
3. LOUD METALLIC IMPACT NOISE—Reference Figure 3:
Check the cushion adjustment. To increase the cushioning effect turn the
cushion screw clockwise (facing the screw driver slot in the cushion screw). If
adjusting the cushion screw does not correct the problem, replacement of the
cushion seal may be required. However, confirm the pressure settings and
operation of externally mounted shock absorbers on the equipment prior to the
replacement of the cushion seal.
When replacing the cushion seal, check the piston for impact damage. If the
piston, piston rod, or rod end shows damage, check the mechanism adjustment
instructions in the machine manual before returning the cylinder to operation.
The cushion seals look like rod and piston seals except the outer body of the
seal is VERY stiff. The outside edge may appear abraded or “sanded.” This is
a sizing process that improves the fit of the seal body in the cavity in the tube
groove side of the head (Figure 3).
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- 3 -
C. GENERAL REBUILD INSTRUCTIONS:
1. GENERAL GUIDELINES:
Remove the cylinder from the equipment and disassemble on a bench or other
clean flat surface.
All necessary parts for the rebuild are contained in the Cylinder Repair Kit for
the specific cylinder used in this equipment.
Clean and inspect all metal parts, particularly the piston rod for wear,
scratches or pitting. Replace the rod if its condition would damage the rod
bushing or seals.
Inspect the piston to piston rod assembly. The piston must be secure on the
piston rod, and the piston nut must be tight. If not, or if there is a question of
the secureness of the assembly, then proceed to the CAUTION SECTION
before continuing with the repair.
2. PISTON & ROD ASSEMBLY w/MIRACALUBE®LUBRICATION
SYSTEM—Reference Figure 1:
On 1.00" to 8.00" bores, apply a thin bead of sealant to the bottom tube
grooves in the Open and Closed Heads. Use either Permatex Form-a-Gasket®
#2 or Locktite® #2 Gasket/Sealant. On 10.00" bore and up, use tube "O"
Rings supplied with kit.
Carefully remove the old piston seals so as not to scratch, nick or burr the lip
or groove of the piston, and gently stretch the new piston seals into the piston
grooves. Be sure that the flat sides of the seals are positioned towards the
center of the piston (Figure 1).
Place the piston and rod assembly in a horizontal position. Remove the
Wicking (Braided Material) and either remove with a sharp hooked scribe or
push all four (4) existing porous plugs into the reservoir. Using the pre-filled
syringe provided, attach the fill nozzle to the syringe with a gentle twisting
motion. Pump about 1/5 of the syringe full into each hole.
Replace the porous plugs with the new plugs provided (some kits may have
one piece of plug material, divide this into four (4) equal lengths). Carefully
press these plug sections fully into the holes. Trim flush, if required with the
bottom of the wicking groove.
Replace the wicking with the new wicking provided being sure the wicking is
stretched tightly. Press the wicking fully into the groove, entirely around the
piston. Trim the excess as necessary with a very sharp knife or side cutters to
form a flush joint.
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Using the remaining lubricant in the syringe, lubricate the seals, wicking and
“mouth” of the tube to ease reassembly.
3. FINAL ASSEMBLY:
Place the Closed Head (Cap End or Back Cover) on a flat surface with the
tube grooved side up. Position the tube in the tube groove lubricated end up.
Carefully, slip the piston and rod assembly into the tube. Be sure that the seal
lips enter the tube without wrinkling, tearing or pinching.
Slide the Open Head (Rod End or Front Cover) over the piston rod being sure
that the tube grooved side is down. Seat the tube in the tube groove (Figure 3).
Slip the rod seal(s) carefully over the rod threads, down the rod and into the
counterbore in the Open Head. Be sure that the seal lips face the head (Figure
2).
Screw the bearing cartridge into the front flange (about 2-1/2 turns). Slide the
bearing cartridge/flange assembly down the rod with the integral seal facing
upwards (this is the rod scraper). Position the flange on the Open Head such
that the “ED” Lock Screw, if present, is properly positioned relative to the
port in the Open Head (Figure 3).
Check the position of the port in the Closed Head relative to the port position
in the Open Head. Insert the tie rods and just snug the tie rod nuts.
Lay the cylinder down on a smooth flat surface, with the mounting points of
the cylinder supported and square the Open Head to the Closed Head. Re-snug
the tie rods as necessary.
Turn the bearing cartridge in until just bottoming on the Open Head which
pre-loads the bearing cartridge threads and tighten to 1-2 foot pounds of
torque.
Alternately (cross-pattern style) tighten the tie rod nuts in even 1/3 steps to the
torque listed in the following table. Confirm the head alignment after each
torque step set. To prevent tie rod rotation during torquing, hold the tie rods
with locking pliers within ½ inch of the respective head.
D. “ED” LOCK SCREW – CYLINDER OPTION:
Reference Figure 3
Tighten the “ED” Lock Screw by gently bottoming the lock screw on the bearing
cartridge (6-8 inch pounds torque). The amount of backing off required can be
confirmed by checking how easily the piston rod assembly moves in and out
(after the rod is clear of the internal cushions).
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E. CAUTION SECTION:
Reference Figures 1, 2 and 3
If the piston to piston rod connection has been loosened, both the piston and
piston rod must be cleaned, degreased, and reassembled prior to using the Repair
Kit.
The carefully cleaned piston and piston rod are assembled using LOCTITE
LOCQUIC PRIMER N®per package directions and LOCTITE REMOVABLE
THREAD LOCKER #242®(BLUE) per package directions.
Remember to install the Cushion Boss "O" Ring and Cushion Boss, as applicable,
and the Piston Rod "O" Ring prior to applying the LOCTITE®products. Do not
allow the LOCTITE®products to come in contact with the "O" Ring(s).
The piston nut is torqued per the following table and the threads staked.
ANY DEVIATION FROM THE LOCTITE®PRODUCT INSTRUCTIONS,
ASSEMBLY PROCEDURE OR CONTAMINATION MAY CAUSE
CATASTROPHIC FAILURE, EQUIPMENT DAMAGE, AND/OR PERSONAL
INJURY.
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- 6 -
LIST OF TYPICAL REPAIR KIT CONTENTS
Repair kits containing all dynamic and static seals are available for all cylinders.
These kits contain:
1 – Piston Rod Bearing Cartridge which includes:
Rod Bearing, Threaded housing, Rod Scraper &
Miracalube Lubrication System
2 – Piston Seals
1 – Piston Rod Seal Set
2 – Piston “O” Ring (use the same as removed “O” Ring)
2 – Wicking Set includes: Porous Plugs, Braided Wicking
1 – Syringe of Miracalube & Insertion Tip (Nozzle)
2 – Cushion Seals (use as required)
2 – Cushion Screw “O” Rings (use as required)
1 set – Cushion Boss and Piston “O” Rings (use as required)
2 – Tube “O” Rings (Supplied in Kits 10.00 Bore & Up)
COMPONENT TORQUE CHART
Bore Piston Rod Tie Rod Piston Nut &
Size Diameter Torque Piston Torque
1-1/2 5/8 & 1 7 Foot Pounds 30 Foot Pounds
2 5/8 & 1 12 Foot Pounds 30 Foot Pounds
2-1/2 5/8 & 1 12 Foot Pounds 30 Foot Pounds
3-1/4 1 & 1-3/8 28 Foot Pounds 140 Foot Pounds
4 1 & 1-3/8 28 Foot Pounds 140 Foot Pounds
5 1 & 1-3/8 50 Foot Pounds 140 Foot Pounds
6 1-3/8 & 2 50 Foot Pounds 290 Foot Pounds
8 1-3/8 & 2 68 Foot Pounds 290 Foot Pounds
10 1-3/4 & 2 130 Foot Pounds 360 Foot Pounds
12 2 & 2-1/2 130 Foot Pounds 360 Foot Pounds
14 2-1/2 & 3 200 Foot Pounds 420 Foot Pounds
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SHOP ONLINE at www.airlinehyd.com
800-999-7378

SHOP ONLINE at www.airlinehyd.com
800-999-7378

SHOP ONLINE at www.airlinehyd.com
800-999-7378

LEHIGH FLUID POWER, INC.
1413 ROUTE 179 • LAMBERTVILLE, NJ 08530
609-397-3487 • FAX# 609-397-0932
www.lehighfluidpower.com
For Toll Free Technical Support Call:
800-257-9515
SHOP ONLINE at www.airlinehyd.com
800-999-7378
Table of contents