Kobelt 4605 Instruction Manual

Kobelt Manufacturing Co. Ltd.
4605 Hydraulic Servo Cylinder
Owner’s Operation, Installation &
Maintenance Manual
April 2019

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NOTES:
RECORD DATA BEFORE INSTALLATION FOR FUTURE REFERENCE
Model #:
Serial #:
Date of Purchase:
Date of Installation:

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TABLE OF CONTENTS
1Introduction ............................................................................................................ 4
1.1 Contact .................................................................................................................... 4
1.2 Safety....................................................................................................................... 4
2Product Description ................................................................................................. 6
2.1 Technical Data ......................................................................................................... 7
3Operation................................................................................................................ 8
4Installation .............................................................................................................. 9
4.1 Mounting ................................................................................................................. 9
4.2 Hydraulic Installation ............................................................................................. 11
5Commissioning ...................................................................................................... 12
5.1 Hydraulic Fill & Bleed............................................................................................. 12
5.2 Functional Test ...................................................................................................... 12
6Maintenance ......................................................................................................... 13
6.1 Preventative Maintenance .................................................................................... 13
6.2 Recommended Spare Parts.................................................................................... 13
7Troubleshooting .................................................................................................... 14
8Warranty............................................................................................................... 15
9Appendix A: Parts List............................................................................................ 16
9.1 4605-4 and 4605-4S Parts Lists .............................................................................. 16
9.2 4605-6, 4605-6S, 4605-8, 4605-8S Parts Lists ........................................................ 17

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1INTRODUCTION
1.1 CONTACT
Kobelt Manufacturing Co. Ltd.
8238 129th Street
Surrey, British Columbia
Canada, V3W 0A6
Sales Tel:
Fax:
Email:
Website:
[phone]
[phone]
[e-mail]
www.kobelt.com
This document is intended to clearly present comprehensive product data and provide
technical information to assist the end user in design applications. Kobelt reserves the right,
without notice, to change the design, or construction, of any products and to discontinue or
limit distribution of any products. Kobelt also reserves the right to change, or update, without
notice, any technical information contained within this document.
Kobelt recommends that customers visit our website to check for updates to this manual.
Once a product has been selected for use, it should be tested by the user to ensure proper
function in all possible applications. For further instructions, please contact our distributors
or visit our website.
1.2 SAFETY
1.2.1 Safety Alerts
Throughout this manual, the following symbols, and their accompanying explanation, are
used to alert the user to special instructions concerning a service or operation that may be
hazardous if performed incorrectly or carelessly. The associated risk levels are stated below.
This symbol indicates an imminently hazardous situation which, if
not avoided, will result in death or serious injury.
This symbol indicates a potentially hazardous situation which, if not
avoided, could result in death or serious injury.
This symbol indicates a hazardous situation, which if not avoided,
could result in minor or moderate injury.
This symbol informs the reader of events not related to personal
injury but which there is a risk of damage to property or equipment.
This symbol informs the reader of safety-related instructions or
procedures.

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1.2.2 Notice to Installer
Disregarding the following safety measures can result in an accident causing severe injury to
personnel and damage to material assets.
•Only use the product as directed in this manual.
•Never put the product into service if there is evidence of visible damage.
•Never put the product into service before fully completing installation and
commissioning.
•Do not carry out any modifications to the product.
•Only use authentic Kobelt spare parts.
•Observe all local regulations, directives and laws during the installation of this product.
•All installation, commissioning, and maintenance work must only be conducted by
qualified personnel. (For the purpose of this manual, qualified personnel are persons
who are familiar with the assembly, installation, commissioning, and operation of the
product and who have the qualifications necessary for their occupation.)
•Observe all specifications in this manual. If these guidelines are not followed and
damage occurs, the warranty will be voided.
1.2.3 Product Hazards
Hydraulic cylinders can produce large forces which can cause injury
to human body parts and damage to nearby components. Keep
body away from moving parts and pinch points. It is the
responsibility of the owner to ensure that the mechanism that the
cylinder is connected to can handle the loads that the cylinder
produces.
This product is powered by hydraulic fluid. Consumption and
contact with eyes can cause death and blindness. Pressurized fluid
jetting out can cause injuries such as hydraulic septicemia. Prior to
beginning work on this product always ensure:
•Safety glasses are being worn.
•Pressure has been exhausted and the pressure source
has been locked out.
•You are qualified to work on hydraulics.
Additionally, it is highly recommended that a relief valve set to the
maximum pressure of this unit is installed to the pressure line
supplying this unit.
To ensure the product does not get damaged during storage and
installation:
•Store the unit with the cylinder fully retracted.
•Ensure all plugs remain in place until unit is ready to be
connected to hydraulics.

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2PRODUCT DESCRIPTION
Controlled by a “push-pull” control but powered by fluid power, the 4605 hydraulic servo
cylinder allows the user to produce half-a-ton of force with minimal human effort. This
product can be used wherever large forces are needed at fingertip actuation. Possible
applications for this unit include waterjet reversing buckets, controlling CP propeller lever
mechanisms, controlling mechanical gearboxes, and steering systems. The 4605 is available in
4”, 6”, and 8” strokes and in either 1/4-28 UNF or 3/8-24 UNF threads on the valve spool and
is fully compatible with Kobelt’s 2000-series Push-Pull control heads and cables.
The 4605 unit consists of two main subunits, the valve and the cylinder. The operating
principles of the cylinder are very simple; pressurized fluid is directed to either end of the
cylinder causing it to retract or extend and exert a force on whatever it is connected to. The
valve is what is used to control the operation of the cylinder; it takes input from the user via
the spool and directs the pressurized fluid where it needs to go to complete the desired
action (i.e. extend, retract, or stay in the current position). See Figure 1 below for a depiction
of the components.
Figure 1: 4605 Components.
This product comes in a few different configurations allowing for a custom-tailored solution
to your needs. Refer to Table 1 on the following page for a listing of the models available and
their operating parameters.

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2.1 TECHNICAL DATA
Table 1: 4605 Technical Data
Operating outside of the ambient temperature range and above the
maximum pressure can result in failure of the unit and will void the
warranty.
MODEL
4605
KOBELT PART #
4605-4
4605-6
4605-8
4605-4S
4605-6S
4605-8S
STROKE,
CYLINDER
4”
10 cm
6”
15 cm
8”
20 cm
4”
10 cm
6”
15 cm
8”
20 cm
STROKE, SPOOL
VALVE
0.62”
15.8 mm
FORCE OUTPUT,
EXTENSION
1160 lbf
5170 N
FORCE OUTPUT,
RETRACTION
1010 lbf
4490 N
FORCE INPUT
< 5 lbf
< 20 N
MAXIMUM
PRESSURE
500 psi
35 bar
VOLUME
9.8 in3
160 mL
14.6 in3
240 mL
19.4 in3
320 mL
9.8 in3
160 mL
14.6 in3
240 mL
19.4 in3
320 mL
AMBIENT
TEMPRATURE
-40 to 140 °F
-40 to 60 °C
WEIGHT
6.6 lbs
3.0 kg
7.8 lbs
3.5 kg
8.9 lbs
4.1 kg
6.6 lbs
3.0 kg
7.8 lbs
3.5 kg
8.9 lbs
4.1 kg
VALVE SPOOL
THREAD
1/4-28 UNF
3/8-24 UNF

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3OPERATION
Note the ambient temperature and maximum pressure specified in
Table 1: 4605 Technical Data on page 7. Exceeding these values can
cause failure of the unit.
The valve takes input from the user mechanically via the spool. Moving the spool valve causes
the cylinder to move in the opposite direction the spool (see Figure 2). It takes approximately
3.1 lbs [14 N] of input force to overcome spool friction.
Figure 2: Cylinder Movement Given a Spool Input.

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4INSTALLATION
4.1 MOUNTING
See Figure 3 on the next page for the dimensions of the 4605 hydraulic servo cylinder. The
mounting of the 4605 to the mechanism to be controlled should precede the connection of
the unit to a source of hydraulic power if possible; for hydraulic installation instructions and
related safety information refer to section 4.2 Hydraulic Installation.
If the cylinder is connected to a hydraulic power source, ensure that
pressure has been exhausted and the pressure source has been
locked out.
The mounting of the 4605 is done as follows:
1. Remove cotter pins and retaining rings from the clevis pins.
2. Remove the clevis pins from the holes they are in.
3. Align clevis pin holes with mechanism cylinder is to be mounted to. Note that the
axial position of the rod end clevis relative to the piston-rod can be adjusted by
loosening the jam nut and screwing or unscrewing the clevis and retightening the
jam nut.
4. Reinstall clevis pins through both holes.
5. Reinstall cotter pins and retaining rings to clevis pins.
6. Connect the valve to the input mechanism (e.g. a Kobelt Push-Pull control) via the
thread on the spool or by another means. Ensure that the spool’s neutral position
lines up with input device’s neutral position to the best of your ability (see Figure 2
for spool neutral positioning). Secure/tighten the connection.
7. Without system pressurization, ensure unobstructed movement of the system for
the full stroke of the cylinder.
Ensure that the mechanism that the cylinder is attached to can
either accommodate the full stroke of the cylinder or is able to
withstand the full load that the cylinder produces at maximum
pressure; damage and failure of the mechanism can occur if this is
not taken into consideration. Note that due to manufacturing
tolerances, the strokes can vary up to 0.08” (2 mm) over the
nominal value (e.g. a cylinder with a nominal stroke of 4” can have
an actual stroke up to 4.08”).

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Figure 3: 4605 Dimensions in Inches [Millimetres]

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4.2 HYDRAULIC INSTALLATION
Hydraulic fluid can cause harmful health effects or death. Contact
with eyes can cause blindness. Pressurized hydraulic fluid jetting can
cause hydraulic septicemia. Due to the harmful health effects of
hydraulic fluid and the inherent risks of dealing with high pressure
fluids only someone knowledgeable and properly trained in the
installation and maintenance of hydraulic systems should work on
this system. Observe the following instructions:
•Wear safety glasses.
•Prior to working on this product ensure that the pressure
has been exhausted and the pressure source has been
locked out.
•Install a relief valve set to the maximum operating
pressure (500 psi/35 bar) and install it to the line
supplying pressure to the cylinder.
•Clean up any spills.
Note the general recommendation for hydraulic installation:
•Ensure plugs remain in place until the unit is ready for
connection.
•All piping and hoses must be flushed prior to connection.
Failure to do so can result in damaged components and
seals.
•All hoses and pipe must also be plugged or capped until
they are ready for connection.
•Connections to the unit must be able to accommodate
the full-movement of the unit (i.e. hard line is unlikely to
work and flexible hose will most likely be needed).
•Piping must be selected and sized to safely withstand the
pressures to operate the unit in the environment that it
will be operating in.
The 4605 cylinder needs to be connected to a source of hydraulic power to function. Supply
pressure to the spool valve should be connected to the port marked by a “P”. The tank return
line should be connected to the port marked by a “T”. The pressure port and tank port
connections are of the SAE -4 ORB and SAE -6 ORB type, respectively.

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5COMMISSIONING
5.1 HYDRAULIC FILL &BLEED
•Open any valves that are installed to the system.
•Fill the system with an anti-wear petroleum-based fluid appropriate for the service
conditions.
•Allow enough time for the cylinder to fill with oil.
5.2 FUNCTIONAL TEST
It is recommended to carry out as much functional testing as
possible before leaving dock and after the entirety of the installation
has been completed.
Before commencing desired operations with the installed unit(s) functional testing should be
conducted to ensure that the 4605 cylinder and the system it is connected to operate as
expected. While testing of the system is somewhat application dependent (e.g. proper
function for actuating a CP propeller vs a waterjet reversing bucket may be different) some
aspects of it can be common. The following is a general outline of a functional test for a 4605
hydraulic servo cylinder; you might need to tailor it to suit your application.
1. Ensure all cotter pins and retaining rings are installed on the clevises.
2. Ensure clevis jam nut and a valve-spool-to-control-cable connection are tight.
3. Without system pressurization, ensure unobstructed movement of the system for
the full stroke of the cylinder.
4. Set the input to the spool valve (e.g. control cable) to neutral.
5. Power on the hydraulics supplied the 4605. Verify:
oThe cylinder does not move from its current position. If it does adjust
the spool position relative to the input device until cylinder movement
stops.
oThere is no leakage occurring.
6. Provide an input to the spool in either direction. Verify that the cylinder is
retracting/extending as expected (Figure 2, page 8).
7. Provide an input to the spool in the opposite direction of step 6. Verify that the
cylinder is retracting/extending as expected.
8. Go through several different inputs of extend, retract, and neutral and observe if
the cylinder is operating as expected.
9. Check for leakage.

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6MAINTENANCE
6.1 PREVENTATIVE MAINTENANCE
•Monthly
oInspect connections, spool valve, cylinder, and interface between spool valve
and cylinder for leakage.
•Quarterly (4 times a year)
oEnsure clevis jam nut and valve-spool-to-control-cable connection are tight.
•Every year
oLubricate clevis pins.
•Every 5 years
oInspect clevis pins. Scoring or wear greater than 0.01” [0.25 mm] requires
replacement of pin.
6.2 RECOMMENDED SPARE PARTS
Kobelt recommends having one of the repair kits for this product on hand; the part number is
4605-RK.
It is recommended that any required service work on a Kobelt unit
be performed by a factory authorized service representative. Please
contact the nearest Kobelt authorized distributor for assistance.

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7TROUBLESHOOTING
If you encounter problems with the operation of your product, please refer to the following
trouble-shooting guide. In case you are still encountering issues after troubleshooting, please
contact Kobelt directly or one of our dealers in your area for assistance.
Table 2: Solutions to Common Problems.
Problem
(Issue encountered)
Cause
(What it means)
Corrective Action
(What to do)
Leakage
Contamination
Replace oil.
Seal failure
Replace leaking seal. Part number for kit
containing replacement seals is 4605-RK.
Excessive back
pressure
Use larger diameter hose.
Reduce length of hose.
Minimize number of fittings.
Excessive system
pressure
Reduce input pressure.
Install pressure relief valve.
Cylinder drifts
Spool is not
centered at neutral
Adjust connection between spool valve
input device and spool until drifting
stops (e.g. adjust the amount that the
spool thread is engaged into the push-
pull control thread).
Leakage past piston
seal
Replace piston seals. Part number for kit
containing replacement seals is 4605-RK.
Moving the valve spool
requires lots of effort
Excessive back
pressure
Use larger diameter hose.
Reduce length of hose.
Minimize number of fittings.
Cylinder goes in
opposite direction than
specified in Figure 2 on
page 8 for a given spool
input; also, likely to be
accompanied with
difficulty in moving
spool.
Pressure input to
valve and tank
return line have
been mixed up
Ensure that port marked with “P” and
“T” are connected to pressure source
and tank, respectively.

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8WARRANTY
Kobelt Manufacturing Co. Ltd. (“Kobelt”) warrants the Products and Parts manufactured by
Kobelt to be free from defects in workmanship or material and that said products are
designed mechanically and functionally to perform to specifications.
This warranty is effective providing:
•The equipment is used within the intended operating conditions and in accordance with
Kobelt recommendations
•The equipment is installed according to equipment diagrams, specifications and
recommendations which Kobelt has provided
This warranty becomes invalid if the factory supplied serial number has been removed or
altered on the product. This warranty does not cover cosmetic damage or damage caused by
an act of God, accident, misuse, abuse, negligence or modification of any part of the product.
This warranty does not cover damage due to improper operation or maintenance, connection
to inappropriate equipment or attempted repair by anyone other than an authorized Kobelt
representative.
Upon identification of a potential issue or defect with a Kobelt Product or Part, the Warranty
Applicant (“Applicant”) must immediately contact Kobelt and describe the issue in writing, by
letter, fax, email or other electronic conveyance. Kobelt will then assess the cause of the
defect, and determine warranty applicability and appropriate remediation.
If any part is found to be defective, Kobelt will replace said part FOB the Kobelt factory
provided that any such defective part is returned by the Buyer with freight and applicable
forwarding charges prepaid by the Buyer. Kobelt’s sole obligation to the Applicant will be to
repair or replace the defective part with same or similar product, to a maximum value of the
list price of the product or part. The Kobelt warranty does not cover labour charges, travel or
any other associated expenses.
All Products and Parts manufactured by Kobelt, are subject to a warranty against
manufacturer’s defects in materials or workmanship for a period of two (2) years from the
date of purchase.
Kobelt will be responsible for all Products or Parts sold by Kobelt but manufactured by 3rd
party manufacturing companies. However, these products and parts are subject to applicable
3rd party warranties, and may not be the same as the Kobelt warranty.

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9APPENDIX A: PARTS LIST
9.1 4605-4 AND 4605-4S PARTS LISTS
Item
Quantity
Part Number
Description
4605-4
4605-4S
1
1
1
4605-4-SUB
Cylinder subassembly, 4”
2
1
-
4605-SA
Valve subassembly, 1/4"-28 thread
2
-
1
4605-SA-3/8
Valve subassembly, 3/8”-24 thread
3
1
1
4605-0419
Length adaptor, 4” stroke
4
1
1
4605-RK
Repair kit
5
4
4
1023-0110
Washer, 1/4", SS
6
2
2
1002-0816
Screw, socket head, 10-24 X 1”, SS
7
4
4
1001-1016
Screw, hex head, 1/4”-20 X 1”, SS

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9.2 4605-6, 4605-6S, 4605-8, 4605-8S PARTS LISTS
Part numbers and their descriptions are on the next page…

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Item
Quantity
Part
Number
Description
4605-6
4605-6S
4605-8
4605-8S
1
1
1
-
-
4605-6-SUB
Cylinder
subassembly, 6”
stroke
1
-
-
1
1
4605-8-SUB
Cylinder
subassembly, 8”
stroke
2
1
-
1
-
4605-SA
Valve
subassembly,
1/4"-28 thread
2
-
1
-
1
4605-SA-3/8
Valve
subassembly,
3/8”-24 thread
3
1
1
-
-
4605-0619
Length adaptor,
6” stroke
3
-
-
1
1
4605-0819
Length adaptor,
8” stroke
4
1
1
1
1
4605-RK
Repair kit
5
2
2
2
2
1001-1016
Screw, hex head,
1/4"-20 X 1”, SS
6
2
2
2
2
1001-1022
Screw, hex head,
1/4"-20 X 1-3/8”,
SS
7
4
4
4
4
1023-0110
Washer, 1/4", SS
8
4
4
-
-
1002-0880
Screw, socket
head, 10-24 X 3”,
SS
8
-
-
4
4
1002-0880
Screw socket
head, 10-24 X 5”,
SS

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Kobelt Manufacturing Co. Ltd.
8238 129th Street
Surrey, British Columbia,
Canada, V3W 0A6
Sales Tel: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.kobelt.com
Made in Canada / Printed in Canada