GUSMER AR-C User manual

"Teamwork & Communication"
Model AR-C/D
Pour Gun
Operating Manual
4943-1-C/D
April 15, 1999
Issue 2
GUSMER CORPORATION ®
A Subsidiary of Gusmer Machinery Group, Inc.
One Gusmer Drive
Lakewood, New Jersey, USA 08701-8055
Toll Free 1-800-367-4767 (USA & Canada)
Phone: [phone]
Fax: [phone]
Copyright 1999, GUSMER CORPORATION ®
http://www.gusmer.com
NOTICE: This manual contains important information for your GUSMER equipment. Read and retain for future reference.

Model AR-C/D Pour Gun
24943-1-C/D, Issue 2
NOTICE: The equipment described in this technical manual must only be operated or serviced by properly trained
individuals, thoroughly familiar with the operating instructions and limitations of the equipment. For technical service,
call your local distributor. Call: 1-800-FOR-GSMR (1-800-367-4767) for the name and telephone number of your local
distributor.
NOTICE: All statements, information and data given herein are believed to be accurate and reliable but are presented
without guarantee, warranty or responsibility of any kind expressed or implied. Statements or suggestions concerning
possible use of GUSMER equipment are made without representation or warranty that any such use is free of patent
infringement, and are not recommendations to infringe any patent. The user should not assume that all safety measures
are indicated or that other measures may not be required.

Operating Manual Contents
4/15/99 3
CONTENTS
LIST OF FIGURES.....................................................................................................4
LIST OF TABLES ......................................................................................................5
WARRANTY...............................................................................................................6
GENERAL SAFETY INFORMATION.....................................................................7
ACCEPTABLE EQUIPMENT USES...................................................................................7
OPERATIONAL SAFETY PROCEDURES...........................................................................8
GENERAL DESCRIPTION.......................................................................................9
PRINCIPLES OF OPERATION........................................................................................ 10
AUTOMATIC GUN HANDLE........................................................................................ 13
EXTENSIVE MAINTENANCE PROCEDURE ...................................................... 16
GUN SERVICE........................................................................................................... 16
GUN BLOCK COMPONENTS........................................................................................ 19
EQUIPMENT SUPPLIED............................................................................................... 20
DISASSEMBLY AND CLEANING OF GUN ...................................................................... 21
Expanded Assembly Procedures .......................................................................... 28
APPENDIX................................................................................................................33
APPENDIX A (AR POUR GUN DIFFERENCES).............................................................. 33
General............................................................................................................... 33
Mechanical Differences....................................................................................... 33
Electrical Differences.......................................................................................... 33
APPENDIX B (TABLES).............................................................................................. 34
APPENDIX C (CHECK LIST FOR MAINTENANCE PROCEDURES)..................................... 35
Disassembly and cleaning of Gun........................................................................ 35
Assembly of Gun.................................................................................................. 35
INSTRUCTION MANUAL DISCREPANCY REPORT......................................... 37

Model AR-C/D Pour Gun
44943-1-C/D, Issue 2
LIST OF FIGURES
FIGURE 1 VALVING ROD STOP IN THE CLOSED OR "SERVICE" POSITION .................................9
FIGURE 2 COUPLING BLOCK CONFIGURATIONS...............................................................10
FIGURE 3 ROD AND THROAT..........................................................................................10
FIGURE 4 IMPINGEMENT OF CHEMICALS.........................................................................11
FIGURE 5 MIXING PROCESS ..........................................................................................12
FIGURE 6 FONT IMPINGER ............................................................................................12
FIGURE 7 AUTOMATIC GUN HANDLE MAJOR COMPONENTS..............................................13
FIGURE 8 VALVE IN OFF POSITION................................................................................13
FIGURE 9 SUPPLYING PILOT PRESSURE...........................................................................14
FIGURE 10 EXHAUSTING CYLINDER PRESSURE................................................................14
FIGURE 11 CONTROL PLUG POSITIONS ..........................................................................15
FIGURE 12 EXAMPLE OF TYPICAL SYSTEM PRESSURES......................................................17
FIGURE 13 MODEL AR-C/D GUN BLOCK COMPONENTS..................................................19
FIGURE 14. AR-C/D GUN TOOL KIT...............................................................................20
FIGURE 15 VALVING ROD ADJUSTMENT STOP .................................................................21
FIGURE 16 MANUAL VALVES .........................................................................................21
FIGURE 17 PATTERN CONTROL TIP REMOVAL..................................................................22
FIGURE 18 SCREEN SCREW MOUNTING SCREW AND PORT CLOSURE PLUGS .......................22
FIGURE 19 SPRING RETAINER CASE ...............................................................................23
FIGURE 20 AIR CYLINDER.............................................................................................23
FIGURE 21 COUPLING BLOCKREMOVAL .........................................................................24
FIGURE 22 CHECK VALVE REMOVAL ..............................................................................24
FIGURE 23 THROAT AND RESIN IMPINGER REMAVAL ........................................................24
FIGURE 24 FLUSH GUN BLOCK .....................................................................................25
FIGURE 25 GUN BLOCK REMOVAL.................................................................................25
FIGURE 26 REMOVING IMPINGER FROM THROAT .............................................................26
FIGURE 27 RESIN IMPINGER SLOTS ................................................................................26
FIGURE 28 ISOCYANATE IMPINGER SLOTS .......................................................................26
FIGURE 29 PATTERN CONTROL TIP ................................................................................27
FIGURE 30 VALVING ROD RESILIENT SLEEVE ASSEMBLY...................................................27
FIGURE 31 ASSEMBLING RESIN IMPINGER INTO THROAT...................................................28
FIGURE 32 THROAT......................................................................................................28
FIGURE 33 INSTALLING CHECK VALVES..........................................................................28

Operating Manual Contents
4/15/99 5
FIGURE 34 ASSEMBLING VALVING ROD INTO GUN ...........................................................29
FIGURE 35 COUPLING BLOCK .......................................................................................29
FIGURE 36 VALVING ROD ADJUSTMENT STOP .................................................................29
FIGURE 37 RESILIENT SLEEVE PROTRUSION....................................................................30
FIGURE 38 RESILIENT SLEEVE WITHDRAWN ....................................................................30
FIGURE 39 CHECK FOR RESIN LINKS..............................................................................30
FIGURE 40 NO WEEPAGE..............................................................................................31
FIGURE 41 WEEPAGE ...................................................................................................31
FIGURE 42 PATTERN CONTROL TIP ASSEMBLY.................................................................31
FIGURE 43 INSERTING PATTERN CONTROL TIP ................................................................32
FIGURE 44 PATTERN CONTROL TIP ................................................................................32
LIST OF TABLES
TABLE 1 IMPINGER PACKAGE AR-C-.250.....................................................................34
TABLE 2 IMPINGER PACKAGE AR-D-.375.....................................................................34

Model AR-C/D Pour Gun
64943-1-C/D, Issue 2
WARRANTY
Gusmer Corporation (Gusmer) provides a limited warranty to the original purchaser (Customer) of
Gusmer manufactured parts and equipment (Product) against any defects in material or
workmanship for a period of one year from the date of shipment from Gusmer facilities.
In the event Product is suspected to be defective in material or workmanship, it must be returned to
Gusmer, freight prepaid. If Product is found to be defective in material or workmanship, as
determined solely by Gusmer, Gusmer will issue full credit to Customer for the freight charges
incurred in returning the defective Product, and either credit will be issued for the replacement cost
of the Product or a replacement part will be forwarded no-charge, freight prepaid to Customer.
This warranty shall not apply to Product Gusmer finds to be defective resulting from: installation,
use, maintenance, or procedures not accomplished in accordance with our instructions; normal
wear; accident; negligence; alterations not authorized in writing by Gusmer; use of “look alike”
parts not manufactured or supplied by Gusmer; or Product used in conjunction with any other
manufacturer's pumping or proportioning equipment. Further, the terms and conditions of this
warranty shall not apply to services or repairs made to Product by any third party not authorized in
writing by Gusmer. For such Product, a written estimate will be submitted to Customer at a
nominal service charge, itemizing the cost for repair. Disposition of Product will be done in
accordance with the terms stated on the written estimate.
The warranty provisions applied to product that are not manufactured by Gusmer will be solely in
accordance with the warranty provided by the original manufacturer of the product.
GUSMER MAKES NO WARRANTY WHATSOEVER AS TO THE MERCHANTABILITY OF,
OR SUITABILITY FOR, ITS PRODUCT TO PERFORM ANY PARTICULAR PURPOSE.
CREDIT FOR, OR REPLACEMENT OF, PRODUCT DEFECTIVE IN MATERIAL OR
WORKMANSHIP SHALL CONSTITUTE COMPLETE FULFILLMENT OF GUSMER
OBLIGATIONS TO CUSTOMER. NO OTHER WARRANTY, EXPRESSED OR IMPLIED ON
ANY PRODUCT IT MANUFACTURES AND/OR SELLS, WILL BE RECOGNIZED BY
GUSMER UNLESS SAID WARRANTY IS IN WRITING AND APPROVED BY AN OFFICER
OF GUSMER.
Under no circumstances shall Gusmer be liable for loss of prospective or speculative profits, or
special indirect, incidental or consequential damages. Further, Gusmer shall have no liability for
any expenses including, but not limited to personal injury or property damage resulting from failure
of performance of the product, use of the product, or application of the material dispensed through
the product. Any information provided by Gusmer that is based on data received from a third
source, or that pertains to product not manufactured by Gusmer, while believed to be accurate and
reliable, is presented without guarantee, warranty, or responsibility of any kind, expressed or
implied.
Gusmer through the sale, lease, or rental of Product in no way expresses or implies a license for the
use of, nor encourages the infringement of any patents or licenses.
To insure proper validation of your warranty, please complete the warranty card and return it to
Gusmer within two weeks of receipt of equipment.
Revised 11/12/98

Operating Manual General Safety Information
4/15/99 7
GENERAL SAFETY INFORMATION
It is necessary to understand and follow the instructions in this manual to insure proper
and safe operation of the equipment.
As with most mechanical equipment, certain safety precautions must be taken when the
equipment discussed in this manual is operated or serviced. Severe bodily injury or
damage to equipment and property may result if the instructions and precautions listed
throughout this manual are not followed.
Needless to say, sufficient guidelines cannot be developed to eliminate the need for good
common sense in the use and servicing of this equipment, and in the use and application
of the products, this equipment has been designed to process. Users of this equipment
must therefore, make their own determination as to the suitability of the information
contained in this manual to their specific operation and requirements. There should be
no assumption made that the safety measures and instructions contained herein are all-
inclusive, and that other safety measures may not be required for specific use or
application.
The following safety guidelines are generally applicable to the safe and efficient use of
the equipment.
Acceptable Equipment Uses
The equipment is designed for the dispensing of polyurethane foams, two-component
coating systems, and some two-component epoxy systems, specifically polyureas. Under
no circumstances should any acid or corrosive chemicals be used in the unit. Consult
GUSMER if there is any doubt about the compatibility of the chemical system to be used
in this equipment.
Any use of this equipment other than as indicated above constitutes misuse unless
express written approval is obtained from GUSMER.

Model AR-C/D Pour Gun
84943-1-C/D, Issue 2
Operational Safety Procedures
This safety information will not be repeated in the text of this manual. The symbols
pertaining to this information will appear where appropriate to alert the operator to
potential hazards.
Solvents and Chemicals
WARNING: THE SOVENTS AND CHEMICAL USED WITH THIS EQUIPMENT EXPOSE THE
OPERATOR TO CERTAIN HAZARDS. ADEQUATE PERSONAL PROTECTIVE MEASURES MUST BETAKEN
SO AS TO AVOID EXCEEDING THE THRESHOLD LIMIT VALUE (TLV) OF THE PRODUCTS BEING
USED, AS ESTABLISHED BY THE OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION (OSHA)
OR OTHER QUALIFIED AGENCY. INFORMATION CONCERNING PERSONAL PROTECTION AND
PROPER HANDLING FROM THE SUPPLIER OF SUCH CHEMICALS.
High Voltage
WARNING:TO PREVENT SERIOUS BODILY INJURY FROM ELECTRICAL SHOCK, NEVER OPEN THE
ELECTRIC CONSOLES OR OTHERWISE SERVICE THIS EQUIPMENT AND/OR EQUIPMENT USED WITH
IT BEFORE SWITCHING OFF THE MAIN POWER DISCONNECT AND INTERRUPTING SUPPLY VOLTAGE
AT THE SOURCE. THE ELECTRICAL SERVICE MUST BE INSTALLED AND MAINTAINED BY A
QUALIFIED ELECTRICIAN.
High Pressure
WARNING:THIS EQUIPMENT HAS OR IS USED WITH EQUIPMENT THAT HAS HYDRAULIC
COMPONENTS CAPABLE OF PRODUCING UP TO 3500 PSI. TO AVOID SERIOUS BODILY INJURY
FROM HYDRAULIC INJECTION OF FLUID, NEVER OPEN ANY HYDRAULIC CONNECTIONS OR SERVICE
HYDRAULIC COMPONENTS WITHOUT BLEEDING ALL PRESSURES TO ZERO.
Personal Protective
Equipment
WARNING:TO AVOID SERIOUS BODILY INJURY, PROPER PROTECTIVE GEAR MUST BE WORN
WHEN OPERATING, SERVICING, OR BEING PRESENT IN THE OPERATIONAL ZONE OF THIS
EQUIPMENT. THIS INCLUDES, BUT IS NOT LIMITED TO, EYE AND FACE PROTECTION, GLOVES,
SAFETY SHOES, AND RESPIRATORY EQUIPMENT AS REQUIRED.
High Temperature
WARNING: THIS EQUIPMENT HAS OR IS USED WITH EQUIPMENT THAT HAS HIGH
TEMPERATURE COMPONENTS SUCH AS PRIMARY HEATERS AND HEATED HOSES. TO PREVENT
SERIOUS BODILY INJURY FROM HOT FLUID OR HOT METAL, NEVER ATTEMPT TO SERVICE THE
EQUIPMENT BEFORE ALLOWING IT TO COOL.
Warning
WARNING: FAILURE TO READ AND FOLLOW THIS SAFETY INFORMATION MAY RESULT IN
PERSONAL INJURY AND/OR DAMAGE TO THE EQUIPMENT FROM ONE OR MORE OF THE ABOVE
LISTED HAZARDS

Operating Manual General Description
4/15/99 9
GENERAL DESCRIPTION
The SR Pour Gun can be considered as consisting of four major detachable components:
Gun Handle, Air Cylinder, Coupling Block, and Gun Block or Mixing Head.
The Gun Handle is a cast aluminum housing containing a re rebuildable Air Valve, a
Switch, and its associated Electrical Connector. The Purpose of the Switch is twofold.
When the AR Pour Gun is used in combination with the TX-50 Microprocessor, the
Switch sends a signal to the logic and control circuit to indicate that the Gun has been
triggered open. This electric signal initiates the Timer or volumetric count sequence
selected. Since movement of the Air Piston activates the Switch, It is an accurate
indication of the position of the Valving Rod.
The Air Cylinder is a two-position, air actuated, spring return cylinder requiring 90-120
psi (6.33-8.44 kg/cm2) air pressure at a minimum of 5 SCFM (2.36 liters/second0 to
function properly. The advantage of a spring return cylinder is that, should there be an
interruption of the air supply, the Gun will automatically go to the closed position. A
further advantage in the design of this Air Cylinder is that it can be completely
disassembled for rebuilding with a Seal Replacement Kit. The Air Cylinder has two
positions of travel, which are selected by a Valving Rod Stop located in the Spring
Retainer Case at the rear of the Air Cylinder.
The closed or "service" position limits the
travel of the Valving Rod and prevents it
from clearing the Throat when the Gun is
triggered. This position serves the two-
fold purpose of acting as a safety to help
prevent accidental discharge of chemical
due to inadvertent triggering of the Gun
and, as the name implies, facilitates the
servicing of the Gun. When the two-
position stop is placed in the "open"
position, the Valving Rod will fully retract
clearing the Throat when the Gun is
triggered allowing the two materials to
mix and dispense. Figure 1Valving Rod Stop in the
closed or "service" position
The AR Pour Gun connects to the Heated Hose Assembly through a Coupling Block
Assembly. This Coupling Block permits quick removal of the AR Gun without the need
to discharge or bleed pressure. This is accomplished by the use of the two manual shut-
off Valves. The Valves have been placed in the Coupling Block with the Valve Seats as
close to the chemical ports in the Gun Block as possible to eliminate chemical residue in
the Block from forming a restriction.
Two polypropylene Gun Block Coupling Gaskets form the seal between the Gun Block
and the Coupling Block. The two Gaskets fit into the Gun Block and the Coupling
Block and extend slightly above the face of the Gun Block to insure a positive seal.
These Gaskets should be replaced as required to maintain a tight seal.

Model AR-C/D Pour Gun
10 4943-1-C/D, Issue 2
The Heated Hose hydraulic fittings are assembled into the Coupling Block in two
different configurations. The 90 degree Coupling Block will align the Hose at a 90
degree angle to the vertical of the Gun Block and is appropriate where the Gun is
suspended from an overhead position. The 10 degree Coupling Block will align the
Hose at a 10 degree angle to the vertical of the Gun Block and is appropriate for hand-
held operation.
Figure 2Coupling Block Configurations
The Gun Block is made of heat treated tool steel and may be considered the base of the
Gun to which all the accessories are attached. The operational principle of the Gun
Block is thoroughly discussed in the following section. It is very important that the
operator learn the terminology and the function of each individual component associated
with the Gun Block.
With a thorough understanding of the operating principle of each of the component
parts, a respect will be developed for their proper care during normal operation and
servicing of the Gun.
Principles of Operation
The Principle behind the operation of the AR Pour Gun is the positive valving or
isolation of the two highly reactive liquid components. This is accomplished by what is
in essence a positive sealing longitudinal valve, created by an elastically deformable
Valving Rod through a Throat section.
Figure 3Rod and Throat

Operating Manual General Description
4/15/99 11
As you can see in this blown-up cross-sectional view of the Rod and Throat, the
dimension of the hole in the Throat through which the Rod must pass is less than the
normal outside diameter of the Rod, thereby creating an "interference" fit with the Rod.
The Rod's construction plays an important role in how this works. It is comprised of
two pieces, a threaded mandril and a Resilient Sleeve. Note that except where it is being
compressed by the interference fit of the throat, the Sleeve fits snugly over the outside
dimension of the threads. As it passes through the Throat, the indentations of the
threads in the mandril permit the elastic sleeve material to deform and fill these
indentations, thereby reducing the outside dimension of the Rod enough to pass through
the Throat. The result is perfect sealing or isolation of the two materials. This might be
more clearly understood by reference to Figure 4Impingement of Chemicals (shown
below), where the relationship of the Throat and Rod to the two materials can be
observed.
Note the "A" material ports are to the front of the Throat section and the "R" material
ports to the rear. The complete sealing created by the interference fit of the Rod through
the Throat completely isolates these two materials from one another in the closed
position, thereby eliminating any chemical reaction. Note too, how the rear
arrangement of the material keeps the Rear Packing Assembly bathed in resin material.
Because of this design, and the nature of the resin material, which actually contains a
lubricant, the maintenance of this Rear Packing O-Ring is virtually eliminated.
Figure 4Impingement of Chemicals

Model AR-C/D Pour Gun
12 4943-1-C/D, Issue 2
Figure 5Mixing Process
The Mixing Process diagram shows the Valving Rod withdrawn to the Pour position.
The Rod's withdrawal has created what in essence is the mixing chamber, or the area in
which the materials impinge and mix. The diagram is somewhat inadequate to convey
the configuration of the ports through which each material passes. In this view, it
appears there are just two ports for each material. Actually, there are several ports for
each created by the Impingers. The Impingers seat against both the front and rear sides
of the Throat section. Below is a close-up view of the front Impinger. Note that its
slotted shape conforms to the concave surface of the Throat upon which it seats. In this
way the slots form ports through which the front material will pass. The Rear Impinger
has a similar slotted surface which bears against and seats on the rear surface of the
Throat. By subdividing the main streams of each material into several sub-streams, the
Impingers accomplish the first step of the mixing process. To further aid mixing, these
slots are inclined toward the slots of the opposite Impinger.
Figure 6Font Impinger
There are virtually no adjustments that the
operator can or needs to make to alter the
pour pattern characteristics that a specific
set of impingers will produce. The
Impinger combination may necessarily
differ from one system to another.
Specifications as to which to use should be
sought from the system supplier or directly
from Gusmer. It is extremely important
that these parts are used in properly matched sets. Identification numbers, which can be
found on all Impingers, are provided to avoid mismatching. While Impingers have not
been engineered to meet the needs of every conceivable system or application, they will
be made available as demand warrants.

Operating Manual General Description
4/15/99 13
Each Impinger carries a three-code identifier. The first two digits identify the size of
each individual slot, the letter identifies the number of slots, and the last digit identifies
the configuration of the slot. For example, 33B1. This identifier code will be used for
ordering and for identification purposes only. Additionally, each Impinger has an
associated Orifice Area Factor as shown in Table I and II in the Appendix. This factor
is a non-dimensional indicator of each Impinger's resistance to flow; i.e., the larger the
Orifice Area Factor, the less the operating pressure created by that Impinger for a
particular liquid temperature and material output through the mixing chamber. When
related to use, the greater area factor simply means less resistance to flow. Depending
on material viscosity's, the greater the area factor, generally will be a greater material
output. This factor is intended for use solely as a guide to aid the operator in what is
essentially a trail and error process of selecting the optimum combination of Impingers
through material testing for a particular chemical system and system application.
Automatic Gun Handle
The Automatic Gun Handle has been designed for use with Gusmer's TX-50
Microprocessor, an Automatic Timer, or Stroke Counter/Encoder Unit. It is necessary
when precise control of the amount of material dispensed is required. The advantage of
this system is the rapid valving action, which is attained with the Automatic Handle plus
the convenience of integrating the components into a lightweight compact unit.
Shown below and on the proceeding page are the major components of the Automatic
Gun Handle. Please take a moment to familiarize yourself with the various components
so that you can relate to them as the operation of the Handle is discussed.
Figure 7Automatic Gun Handle Major Components
The cross-section of the AR Gun
is shown in the closed or "off"
position - the spool valve is closed
(forward). In this position, there
is no line pressure to the Gun, nor
is there pilot pressure to the spool
valve.
Figure 8Valve in OFF Position

Model AR-C/D Pour Gun
14 4943-1-C/D, Issue 2
The AR Gun is now in the open
or "dispense" position - the spool
valve is open (rearward). When
the Trigger Lever is depressed,
the trigger switch closes which in
turn energizes the Pilot Valve to
the open position and permits
pilot pressure to be supplied to
the spool valve, moving it
rearward. This movement directs
air pressure into the Air Cylinder,
causing the AR Gun's Valving
Rod to open against the action of
the return spring. Figure 9Supplying Pilot Pressure
When the Trigger Lever is
released, the Trigger Switch
opens, de-energizing the pilot
valve, which then exhausts the
pilot pressure. The release of
pilot pressure causes the spool
valve to move forward shutting
off the air pressure to the Air
Cylinder, and opens the Gun
Cylinder exhaust port. Under the
action of the return spring, the
Valving Rod moves forward to
the closed position. Figure 10 Exhausting Cylinder Pressure
The electric power to operate the solenoid valve is supplied from the Gusmer TX-50
Microprocessor Automatic Timer or Volume Counter.
The Gun Switch serves two distinct purposes. When used in conjunction with the
Gusmer TX-50 Automatic Timer selection, the Gun Switch signals the Timer to start. It
is significant to note that the Gun Switch is located in such a manner that is actuated by
movement of the Piston in the Air Cylinder. The advantage here is that the activation of
the switch is an exact indication that the Gun is opened or closed. When the TX-50
Volume Counter has been selected, the Gun Switch is used to simultaneously activate or
deactivate the Directional Valve on the Proportioning Unit, in addition to the TX-50
Microprocessor.
A mode selector has been provided on the Circuit Board in the Gun Handle to allow use
of the Gun in a completely automatic hands-off operation. The two positions of the
control plug; i.e., normal (NORM) and automatic (AUTO) are shown below. In the
normal position, the Gun will only open when the Trigger Lever is depressed. In the
auto position, the Trigger Lever is bypassed, and the Gun will open on command of the
TX-50 timer, counter, or a remote switch such as a foot switch. When the auto position
is used in sequence with the reset cycle of the TX-50 timer or counter, a completely
automatic system can be realized.

Operating Manual General Description
4/15/99 15
Figure 11 Control Plug Positions
WARNING: WHEN THE MODE SELECTOR IS IN THE AUTO POSITION, THE EFFECT WILL BE THE
SAME AS MANUALLY DEPRESSING THE TRIGGER LEVER. THEREFORE, WHENEVER ELECTRICAL
POWER IS APPLIED TO THE GUN, THE GUN WILL OPEN.
To prevent accidental operation of the Gun, it is VERY IMPORTANT that the
following steps are accomplished during any shutdown:
1. Close both Manual Valves.
2. Disconnect the Air Line at the Gun.

Model AR-C/D Pour Gun
16 4943-1-C/D, Issue 2
EXTENSIVE MAINTENANCE PROCEDURE
Gun Service
This section of the Manual has been prepared to acquaint the operator with the
suggested procedures for servicing the Gun. Your attention is drawn to the degree of
proficiency with which the valving mechanism in the Gun must perform to make
foaming in place practical. It should be understood that chemical reaction starts the
instant the two chemicals contact each other. The slightest leakage across the throat
will eventually cause blockage resulting in restriction to flow or possibly stoppage of
one material completely. Easy access to the inner workings of the gun has been
provided because, while there will be periods of many days without a "misfire", there
will also be occasions when all does not work perfectly.
There are some absolutely essential requirements that must be met for the AR Pour
Gun to continue to perform with the high degree of efficiency for which it was
engineered.
The two most important considerations for continuous reliable operation are that there
is always positive sealing of the Rod through the Throat, and always an adequate
supply of the materials to the Gun.
It has already been explained how the positive sealing is accomplished and its
importance in terms of the advantages it provides. The effectiveness of the seal created
by this design, as you will see as you go through the assembly procedures provided, is
quite remarkable. A new, undamaged Valving Rod through a Throat that has no nicks
or mars will withstand up to 2000 psi (140.61 Kg/cm2) rear material pressure with no
weepage. In actual use, you must realize that with material under pressure on both
sides of the Throat, the leakage potential would be the difference in pressure between
the two materials. Nevertheless, monitoring the condition of these parts and the
effectiveness of this seal is an important responsibility of the Gun operator. A pressure
check of this seal should be conducted periodically to determine if the Rod is worn or
either the Rod or Throat is damaged. Minor weepage is the first sign of wear and is
unacceptable. The pressure check should produce "bone dry" results. While wear of
the Valving Rod Sleeve is beyond the control of the operator, damage to ether the Rod
or the Throat can only occur as a direct result of negligence, improper handling, or
maintenance. Care must be exercised in following the procedure of mounting and
removing the Pattern Control Tip. Unless the Rod is withdrawn to the service position,
the turning motion of the Pattern Control Tip can cause damage to the Rod. Also the
highly polished through-hole of the Throat must be treated with great care; any hard
metal object can damage this surface, which in turn will quickly destroy the Valving
Rod Sleeve, and render the Throat useless.
The importance of maintaining and adequate supply of both materials to the Gun at all
times cannot be over emphasized. While the Gun is in the pour position, the
continuous flow of each material is relied upon to keep the materials from migrating
through the opposite material's Impinger slots. In other words, a continuous supply of
each material must be maintained or a crossover can occur. Below is an example of
what pressures might be with a typical system. When the Rod is in the pour position
and both material pressures are at about 800 psi (56.25 Kg/cm2) in the Gun ports and
Impinger slots, note that each pressure drops to under 300 psi (21.09 Kg/cm2) as it
leaves the small Impinger slots and enters the larger mixing chamber area. As long as

Operating Manual Extensive Maintenance Procedure
4/15/99 17
there is a continuous supply of both materials and each is at a pressure greater than the
materials in the mixing chamber area. Then this lower pressure material in the mixing
chamber area can only go out the front of the Gun. By contrast, however, a momentary
interruption of flow of one material will allow the material in the chamber area to flow
back toward the Proportioner through the Impinger Slots. While this reversal of flow
would cause the check valve in the bottom of the Gun Block to close, thereby
preventing the cross-over from being extensive, it cannot prevent cross-over into the
Impinger slots and the internal porting of the Gun Block.
Figure 12 Example of Typical System Pressures
If the crossed-over material reacts within the Impinger slots it will, since it cannot be
purged by the Valving rod, remain as a restriction to flow. The AR Gun then must be
disassembled to clean the effected areas, and the problem at the Proportioner, which
caused the crossover, corrected before pouring is resumed.
Usually an interruption of flow of one material can be detected by a competent
operator. It will cause a change in color of the mixed product, or in the case of severe
interruption, just one component coming out of the Gun. Naturally, it is best, and
worth the extra effort to never allow this situation to occur. The most frequent causes
are running out of material, trying to feed the Proportioner with materials that are too
viscous, or allowing the filter screens to become restricted. Generally, check each
during daily maintenance.
Selection of the set of Impingers, which will most efficiently mix a particular foam
system, is of great importance in getting the most out of the AR Pour Gun. Basically,
the selection process is one of trial and error.
Once the proper Impingers are selected, there are no adjustments to make to the Gun to
control the pour pattern. When a good pattern is not attained, there are just two
probable causes. Either the materials entering the Gun are not at suitable viscosity's, or
the Impinger slots are clogged. Temperature, controlled by the Primary Heater(s)
setting and/or Hose Heater setting, is your only control over viscosity. Because of the
improved mixing capabilities of the AR design, there is, for most systems, a wider
temperature range throughout which good mix and pattern development should be
attained. Your system supplier should furnish the recommended temperature range
that should be maintained. Since pattern development is not that sensitive to
temperature, restricted Impinger slots would probably be a more frequent cause of bad
pattern.

Model AR-C/D Pour Gun
18 4943-1-C/D, Issue 2
Restricted Impinger slots would be due either to particles in the material or a slight
crossover. If the Proportioner Unit filter and Gun Filter Screens are properly
maintained the incident of particles in the material restricting the Impinger slots
should be extremely rare. A restriction from a crossover, on the other hand, is possible
if interruptions in the supply of materials are allowed - remember even the slightest
interruption, probably undetectable in the pour can cause a restriction due to a
crossover.
There are just a few other points, which would be helpful to keep in mind to assure
maximum efficiency from the AR Pour Gun.
Properly maintaining the Check Valves, their Gaskets and the cavities in the Gun
Block in which the Check Valves float will assure positive seating. This will reduce
the severity of a crossover in the event of such a circumstance is allowed to occur. This
entails maintaining Gaskets and Valve bodies free of nicks and mars and assuring
springs are kept free of material build-up. Also, be sure to keep the Check Valve
cavities clean from any material build-up to assure free movement of the Check Valves.
The Check Valve removal tool has been specifically designed to be used to clean the
Check Valve cavities.
The design of the AR Pour Gun does not provide simultaneous valving of both
materials; instead the design provides a valving action which is so rapid that the effect
on the resulting product of having the front material valved first is insignificant. The
high flow air Quick Disconnect and fast dumping Air Valve are essential to this design
and should not be replaced by alternate designs. Also, you must maintain an adequate
supply of air at 90-120 psi 96.33-8.44 Kg/cm2) to the Gun. Failure to maintain the
rapid valving action will cause a small amount of Isocyanate material to be detectable
upon both the opening and closing of the Valving Rod.
Generally, the only parts requiring periodic replacement are the Valving Rod Sleeve
Assembly and the Front Packing. Proper procedure for determining when replacement
is required and how to make these replacements are covered in the Gun Assembly
Procedures.
Before proceeding with the following procedures, familiarize yourself with Figure 13
Model AR-C/D Gun Block Components and Figure 14. AR-C/D Gun Tool Kit (shown
on the next two pages), so that you may relate to them as you read this section of the
Manual.

Operating Manual Extensive Maintenance Procedure
4/15/99 19
Gun Block Components
Figure 13 Model AR-C/D Gun Block Components
1. Pattern Control Tip
2. O-Ring
3. Front Packing
4. Front Impinger
5. Throat
6. Rear Impinger
7. Screen Screw Mounting Screw
8. R – Port Closure Screw
9. Gun Block
10. Resin Seal Retainer
11. Spacer
12. Resin Seal Screw
13. O-Ring
14. Resin Packing
15. A – Port Closure Screw
16. Gun Block Screen
17. Gun Block Screen Screw
18. Screen Screw Seal
19. Snap Ring
20. A – Check Valve
21. Coupling Block Gaskets
22. R – Check Valve

Model AR-C/D Pour Gun
20 4943-1-C/D, Issue 2
Equipment Supplied
Figure 14. AR-C/D Gun Tool Kit
Tools Required
1. Flush Can
2. Impinger Cleanout Brush
3. 5/16” Nut Driver
4. Utility Knife
5. Pin Vise with Cleanout Spade
6. Gun Block Component Hole Cleanout
Brush
7. Check Valve Removal Tool
8. Throat Wrench
9. Pattern Control Tip Front Impinger
Packing Seal Cleanout Tool
10. Gasket Removal Tool
11. Wooden Stick
12. Pry Tool/Rear Impinger Wrench
13. Optional: Pressure Flush Kit (Not
Shown)