Milton Roy GM Series User manual

Series G Model “M” Pump
Instruction Manual
GM.MR.ENG.339-0080-000.04/2020

GM Series Liquid End Connection Code L Standard Pump Installation
1.GM series liquid end connection
code L standard pump installation,
pressure cap (8.03) can’t be
disassembled from lock ring (8.02)
and bushing (8.01) assembly, only
when connect with tubing(P), press
fitting pressure cap to check valve
assembly.
2. Assembly 7 and series 1~6 parts
are assembled as component.
Assembly 8 (contain 8.1~8.3) are
delivered as completely knock
down.
3. Put tubing P across pressure cap
(8.03) and lock ring (8.02), connect
to bushing (8.01), then tighten
pressure can to check valve body.
4. Replacement of pressure cap
(8.03) and lock ring (8.02) and
bushing (8.01) as assembly when
need to disassembled or change
tubing.
Before connect
to tubing
After connect
to tubing
Note
●Sulfuric acid, nitric acid and other strong acid material, strong recommend to use PE hose, and regular
inspection, changing in time when hose is aging and damaged.

I
TABLE OF CONTENTS
SECTION 1 DESCRIPTION………………………………………………………………………………....................1
1.1 GENERAL INFORMATION………………………………………………………………………….....................1
1.2 PRINCIPLES OF OPERATION…………………………………………………………………………………....2
1.3 GENERAL SPECFICATIONS………………………………….…………………………………………….........3
SECTION 2 INSTALLATION…………………………………………………………………………………………....4
2.1 UNPACKING………………………………………………………………………………………………………...4
2.2 STORAGE…………………………………………………………………………………………………………...4
2.3 SAFETY PRECAUTIONS……………………………………………………………………………………….....5
2.4 MOUNTING…………………………………………………………………………………………………….…....6
2.5 DRIP COLLECTION…………………………………………………………………………………………….…..6
2.6 INSTALLATION……………………………………………………………………………………………….…..…6
2.6.1 NPSH CONSIDERATIONS……………………………………………………………………………...…..8
2.6.2 GENERAL PIPING CONSIDERATION……………………………………………………………….…....8
2.6.3 SUCTION PIPING CONSIDERATION……………………………………………………………..………9
2.6.4 DISCHARGE PIPING CONSIDERATION……………………………………………………...…...……..9
2.7 VALVES……………………………………………………………………………………………………..……...10
2.8 ELECTRICAL CONNECTIONS………………………………………………………………………………….10
SECTION 3 OPERATION……………………………………………………………………………………………....11
3.1 START-UP PROCEDURES AND CHECKS……………………………………………………………...……..11
3.2 CHECKING THE ELECTRICAL CONNECTION OF THE MOTOR…………………………………..……...11
3.3 START-UP……………………………………………………………………………………………………..…...11
3.4 CAPACITY CALIBRATION………………………………………………………………………………..……...12
SECTION 4 MAINTENANCE……………………………………………………………………………………...…..13
4.1 PREVENTATIVE MAINTENANCE………………………………………………………………………..……..13
4.2 RETURNING PUMPS TO THE FACTORY FOR REPAIR………………………………………….……..…..13
4.3 ROUTINE MAINTENANCE………………………………………………………………………………….…...13
4.4 SPARE PARTS………………………………………………………………………………………………..…...14
4.4.1 GM0002~GM0050 Liquid End - PVC and PVDF………………………………………………………..14
4.4.2 GM0002~GM0050 Liquid End - Stainless Steel…………………………………….........................…14
4.4.3 GM0090~GM0500 Liquid End - PVC and PVDF………………………………………………………..15
4.4.4 GM0090~GM0500 Liquid End - Stainless Steel…………………………………………………………15
4.5 CORRECTIVE MAINTENANCE…………………………………………………………………………………15
4.5.1 Check Valve Replacement: Liquid End GM0002~GM0050 - PVC & PVDF………………………….16
4.5.2 Check Valve Replacement: Liquid End GM0002~GM0050 –Stainless Steel…………………….…..17
4.5.3 Replacement of Ball, Seat & Seal: Liquid End GM0090~GM0500 - PVC & PVDF………………….17
4.5.4 Check Valve Replacement: Liquid End GM0090~GM0500 - Stainless Steel………………………..18
4.6 DIAPHRAGM AND OIL SEAL BELLOWS REPLACEMENT………………………………………….………19
4.6.1 Diaphragm Replacement: Liquid End Size GM0002~GM0050………………………………………..19
4.6.2 Diaphragm Replacement: Liquid End Size GM0090~GM0500………………………………………..20
4.7 OIL SEAL BELLOWS REPLACEMENT………………………………………………………………….……..21
4.8 RESTARTING THE PUMP……………………………………………………………………………….………21

II
SECTION 5 PARTS LIST…………………………...………………………………...………………………………. 23
5.1 PARTS LIST FOR GM DRIVE SIDE VIEW………………………………………………………...………..…24
5.2 PARTS LIST FOR GM DRIVE END VIEW………………………………...……………………………..…….26
5.3 PARTS LIST FOR GM0002~GM0010 PVC, PVDF&MIXED LIQUID END-
TUBING CONNECTION…………………………………………………………….…………………………....28
5.4 PARTS LIST FOR GM0002~GM0010 PVC, PVDF LIQUID END-
LMI (PE) TUBING CONNECTION……………………………………………………………………..……...…30
5.5 PARTS LIST FOR GM0002~GM0010 PVC LIQUID END-
THREADED CONNECTION………….…………………………….………...………………………..……...…32
5.6 PARTS LIST FOR GM0002~GM0010 STAINLESS STEEL LIQUID END-
THREADED CONNECTION…………………………………………………………………………………...…33
5.7 PARTS LIST FOR GM0002~GM0010 HIGH VISCOSITY LIQUID END -
TUBING CONNECTION…………………………………………………………...………………………..……34
5.8 PARTS LIST FOR GM0025~GM0050 PVC, PVDF&MIXED LIQUID END -
TUBING CONNECTION…………………………………………………………...…………………………..…36
5.9 PARTS LIST FOR GM0025~GM0050 PVC, PVDF LIQUID END-LMI (PE)
TUBING CONNECTION………………….………………………………………………………………..…..…38
5.10 PARTS LIST FOR GM0025~GM0050 PVC LIQUID END -
THREADED CONNECTION………..….……………….…….………………………………………….....……39
5.11 PARTS LIST FOR GM0025~GM0050 STAINLESS STEEL & SLURRY LIQUID END -
THREADED CONNECTION…………………...…….…………………………………………………..…...….40
5.12 PARTS LIST FOR GM0025~GM0050 HIGH VISCOSITY LIQUID END -
TUBING CONNECTION………...............................……………………………………………………….......42
5.13 PARTS LIST FOR GM0090~GM0500 PVC & MIXED LIQUID END……………………………….....……..45
5.14 PARTS LIST FOR GM0090~GM0500 PVDF LIQUID END………………………………………….....…….47
5.15 PARTS LIST FOR GM0090~GM0500 STAINLESS STEEL LIQUID END…………………………..……....49
5.16 PARTS LIST FOR GM0090~GM0500 HIGH VISCOSITY LIQUID END……………………………..…...…51
5.17 PARTS LIST FOR GM DOUBLE DIAPHRAGM LIQUID END………………………………………….....….55

III
LIST OF ILLUSTRATIONS
Figure 1-1. Pump Assembly……………………………………………………………………………………….......1
Figure 1-2. Stroke Control Operating Principle…………………………………………………………………...…2
Figure 2-1. Series G Model M Dimensional Outline……………………………………………………………......5
Figure 2-2. Typical Installation…………………………………………………………………………………..........7
Figure 2-3. General Piping………………………………………………………………………………………..…...8
Figure 2-4. Terminal Connection for 3-Phase Electrical Motor…………………………………………………....11
Figure 5-1. GM Drive Side View……………………………………………………………………………………..23
Figure 5-2. GM Drive End View…………………………………………………………………………………..... 25
Figure 5-3. GM0002~GM0010 PVC, PVDF & Mixed Liquid End-Tubing Connection………………………....27
Figure 5-4. GM0002~GM0010 PVC, PVDF Liquid End -LMI (PE) Tubing Connection………………............ 29
Figure 5-5. GM0002~GM0010 PVC Liquid End-Threaded Connection…………………………………….......31
Figure 5-6. GM0002~GM0010 Stainless Steel Liquid End-Threaded Connection………………………….....33
Figure 5-7. GM0002~GM0010 High Viscosity Liquid End-Tubing Connection…………………………………34
Figure 5-8. GM0025~GM0050 PVC, PVDF & Mixed Liquid End-Tubing Connection……………………...... 35
Figure 5-9. GM0002~GM0010 PVC, PVDF Liquid End -LMI (PE) Tubing Connection………………............37
Figure 5-10. GM0025~GM0050 PVC Liquid End-Threaded Connection…………………………………….......39
Figure 5-11. GM0025~GM0050 Stainless Steel & Slurry Liquid End-Threaded Connection………………......40
Figure 5-12. GM0025~GM0050 High Viscosity Liquid End-Tubing Connection………………………………....41
Figure 5-13. GM0090~GM0500 Spacer…………………………………………………………………………….. 43
Figure 5-14. GM0090~GM0500 PVC, PVDF & Mixed Liquid End……………………………………………….. 44
Figure 5-15. GM0090~GM0500 Stainless Steel & Slurry Liquid End……………………………………………. 48
Figure 5-16. GM0090~GM0500 High Viscosity Liquid End………………………………..………………………...50
Figure 5-17. GM Double Diaphragm Leakage Detection with Pressure Gauge Sectional View……………….53
Figure 5-18. GM Double Diaphragm Leakage Detection with Pressure Gauge and Switch Sectional View... 54

1
SECTION 1 DESCRIPTION
1.1 GENERAL INFORMATION
The Series G Model M is a reciprocating, chemical dosing pump capable of producing ows up to 500 liters
per hour at pressures up to12 Bar. These pumps feature a mechanically actuated diaphragm Iiquid end, which
eliminates the need for flow-restricting contour plates, and a stroke adjustment mechanism based on the
variable eccentric principle instead of the traditional lost-motion design. It is designed for industrial service and
offers an accuracy of ±1.5% of full rated ow between 10% and 100% of its ow range.
The basic pump components as illustrated in Figure 1-1 are:
a drive device comprising a motor (1)
a mechanical assembly (2)
a liquid end (3)
An elastomeric bellows provides an Ieak-tight seal between the mechanical assembly and the liquid end.
Capacity adjustment is manually controlled by a stroke adjustment knob (4).
Figure 1-1：

2
1.2 PRINCIPLES OF OPERATION DRIVE ASSEMBLY(SEE FIGURE 1-2)
The pump consists of two major assemblies; the drive and the liquid end. Pump delivery is a function of the
drive's stroke rate, liquid end size and stroke length. Stroke length can be increased while the pump is running
by counterclockwise turning of the stroke adjustment knob. The drive assembly works on the principle of a
variable eccentric. The rotational motion of the motor is transmitted by the worm (1) to the worm gear(2) which
is linked to an eccentric system (3). The eccentric system then converts the rotary gear motion into linear
reciprocating motion of the connecting rod(4). At 0% capacity setting, the connecting rod axis (B) is aligned
with the gear axis (A) and no movement of the connecting rod takes place. At 100% capacity setting, an
eccentricity exists between the connecting rod axis (B) and the gear axis (A) which results in linear movement
of the connecting rod and resulting pumpage.
Mechanically Actuated Diaphragm Liquid End(See Figure 1-2)
The diaphragm assembly (5) is mechanically linked to the connecting rod (4) and has the same reciprocating
motion. As the diaphragm starts back on the suction stroke, the pressure immediately drops inside the liquid
end. When the pressure in the liquid end drops below the suction line pressure, the suction ball check is
"pushed" upward and the process uid in the suction line ows into the liquid end chamber (diaphragm head).
When the suction stroke ends, the diaphragm movement momentarily stops and the pressure in the liquid end
equalizes with the pressure in the suction line causing the suction ball check to reseat.
NOTE: It is important that the pressure in the liquid end remain above the vapor pressure of the process
uid during the suction stroke. If the uid pressure drops below the vapor pressure, cavitation will occur
which will have a negative impact on the performance of the pump. If you suspect the possibility of
cavitation, contact your dealer for assistance.
Figure 1-2：

3
As the diaphragm starts forward on the discharge stroke the pressure immediately rises inside the liquid end.
When the liquid end pressure rises above the discharge line pressure; the discharge ball check is "pushed"
upward and the process uid in the liquid end ows into the discharge line. When the discharge stroke ends,
the diaphragm momentarily stops again. The pressure in the liquid end equalizes with the discharge line
pressure and the discharge ball check reseats. The cycle then starts again.
1.3 GENERAL SPECIFICATIONS
FLOW RATE:
Up to 500 L/H (depending on pump code)
PRESSURE:
Up to 12 BAR (depending on pump code)
LIQUID END TYPE:
Mechanically Actuated Diaphragm
DRIVE TYPE:
Variable Eccentric
STEADY STATEACCURACY:
±1.5% of pump full rated capacity between 10% and 100% of rated capacity.
CAPACITY ADJUSTMENT:
Lockable stroke adjustment knob is adjustable from 0% to 100% while pump is running.
LUBRICATION:
Drive is lubricated in an oil bath (Oil model refer to chapter 3.1).
TEMPERATURE:
Ambient and Liquid:
40 ℃Maximum
-10 ℃Minimum
SUCTION LIFT:
2 meters of water column maximum
11.5 psia minimum internal pressure(3.2 psi maximum Vacuum)

4
SECTION 2 INSTALLATION
2.1 UNPACKING
Pumps are shipped f.o.b. factory or representative warehouse and the title passes to the customer when the
carrier signs for receipt of the pump. In the event that damages occur during shipment, it is the responsibility of
the customer to notify the carrier immediately and to le a damage claim. Carefully examine the shipping crate
upon receipt from the carrier to be sure there is no obvious damage to the contents. Open the crate carefully
so accessory items fastened to the inside of the crate will not be damaged or lost. Examine all material inside
the crate and check against packing list to be sure that all items are accounted for and intact.
2.2 STORAGE
Short Term Storage (Less than 6 Months)
It is preferable to store the material under a shelter in its original package to protect it from adverse weather
conditions. In condensing atmospheres follow the long term storage procedure.
Long Term Storage (Longer than 6 Months)
The primary consideration in storage of pump equipment is to prevent corrosion of external and internal components.
This corrosion is caused by natural circulation of air as temperature of the surroundings change from day to night, day to
day, and from season to season. It is not practical to prevent this circulation which carries water vapor and other corrosive
gasses, so it is necessary to protect internal and external surfaces from their effects to the greatest extent possible.
When the instructions given in this section are completed, the equipment is to be stored in a shelter; protected
from direct exposure to weather. The prepared equipment should be covered with a plastic sheet or a
tarpaulin, but in a manner which will allow air circulation and prevent capture of moisture. Equipment should
be stored 12 inches or more above the ground.
If equipment is to be shipped directly from the factory into long term storage, contact the factory to arrange for
factory preparation.
Pump Drive
1. Remove motor and ood the gearbox compartment (ltem 2 in Figure 1-1) with a high grade lubricating
oil/rust preventative such as Mobile Oil Corporation product Mobilarma 524. Fill the compartment com-
pletely to minimize air space and water vapor condensation. After storage, drain this material and rell
the equipment with the recommended lubricant for equipment commissioning.
2. Brush all unpainted metal surfaces with multipurpose grease (NLGI grade 2 or 3). Store these
unattached.
Electrical Equipment
1. Motors should be prepared in the manner prescribed by their manufacturer. If information is not
available, dismount and store motors as indicated in step 3 below.
2. Dismount electrical equipment (including motors) from the pump.
3. For all electrical equipment, place packets of Vapor Phase Corrosion Inhibitor (VPCI) inside of the enclosure,
then place the entire enclosure, with additional packets, inside a plastic bag. Seal the bag tightly.

5
2.3 SAFETY PRECAUTIONS
WHEN INSTALLING, OPERATING, AND MAINTAINING THIS PUMP, KEEP SAFETY
CONSIDERATIONS FOREMOST. USE PROPER TOOLS, PROTECTIVE CLOTHING, AND EYE
PROTECTION WHEN WORKING ON THE EQUIPMENT AND INSTALL THE EQUIPMENT WITH A
VIEW TOWARD ENSURING SAFE OPERATION. FOLLOW THE INSTRUCTIONS IN THIS MANUAL
AND TAKE ADDITIONAL SAFETY MEASURES APPROPRIATE TO THE LIQUID BEING PUMPED. BE
EXTREMELY CAREFUL IN THE PRESENCE OF HAZARDOUS SUBSTANCES (E.G., CORROSIVES,
TOXINS, SOLVENTS, ACIDS, CAUSTICS, FLAMMABLES, ETC.).
THE PERSONNEL RESPONSIBLE FOR INSTALLATION, OPERATION AND MAINTENANCE OF THIS
EQUIPMENT MUST BECOME FULLY ACQUAINTED WITH THE CONTENTS OF THIS MANUAL.
ANY SERVICING OF THIS EQUIPMENT MUST BE CARRIED OUT WHEN THE UNIT IS STOPPED
AND ALL PRESSURE HAS BEEN BLED FROM THE LIQUID END. SHUT-OFF VALVES IN SUCTION
AND DISCHARGE SIDES OF THE LIQUID END SHOULD BE CLOSED WHILE THE UNIT IS BEING
SERVICED. ACTIONS SHOULD BE TAKEN TO ELIMINATE THE POSSIBILITY OF ACCIDENTAL
START-UP WHILE SERVICING IS TAKING PLACE. A NOTICE SHOULD BE POSTED BY THE POWER
SWITCH TO WARN THAT SERVICING IS BEING CARRIED OUT ON THE EQUIPMENT. SWITCH OFF
THE POWER SUPPLY AS SOON AS ANY FAULT IS DETECTED DURING OPERATION (EXAMPLES:
ABNORMALLY HIGH DRIVE TEMPERATURE, UNUSUAL NOISE, DIAPHRAGM FAILURE).
WARNING
CAUTION
Figure 2-1：

6
2.4 MOUNTING
Support the pump rmly in a level position on a solid, vibration-free foundation. The pump should preferably be
positioned with the base above oor level to protect the pump from wash downs and to provide easier access
for service. Be sure to allow enough space around the pump for easy access during maintenance operations
and pump adjustments.
The pumps are provided with mounting holes to accommodate anchor bolts. Refer to Figure 2-1 for mounting
hole dimensions.
Pumps installed outdoors should be protected by a shelter.
2.5 DRIP COLLECTION
In the event of a failure of the diaphragm or oil seal bellows, provisions need to be made to contain the
process uid or pump oil. This is particularly important when handling uids which may be harmful to plant
personnel.
To collect uid in the event of a diaphragm or oil seal rupture, (See Figure 1-1) position a tray under the plain
hole located at the bottom of the liquid end mounting assembly (5). For GM0090 ~ GM0500 pumps, position
tray under tube tting located at bottom of liquid end mounting assembly. Alternatively, a tube may be installed
onto this tube tting to drain any leakage to a suitable container.
2.6 INSTALLATION
Figure 2-2 displays typical installations (both correct and incorrect). Figure 2-3 illustrates the recommended
piping and accessories in a metering pump installation.
As illustrated in the upper right portion of Figure 2-2, there must be no swan-necks or stagnant volumes in
the suction line. In this illustration, the loop at the top of the tank forms an air trap. Eventually, air or gases will
bubble out of solution and accumulate in the trap leading to a loss of prime condition.

7
Figure 2-2：

8
2.6.1 NPSH CONSIDERATIONS
Size piping to accommodate peak instantaneous flow. Because of the reciprocating motion of the
pump diaphragm, peak instantaneous ow is approximately equal to 3.14 times the average ow. For
example, a pump rated for 100 L/hr per hour requires piping sufcient for 3.14 x 100 L/hr (314 L/hr.).
To minimize viscous ow losses when handling viscous liquids, it may be necessary to use suction
piping up to four times larger than the size of the suction connection on the pump. If in doubt, contact
your dealer to determine the necessary pipe size.
2.6.2 GENERAL PIPING CONSIDERATIONS
Use extreme care in piping to plastic liquid end pumps with rigid pipe such as PVC. If excessive pipe
stress or vibration is unavoidable, exible connections are recommended.
Use piping materials that will resist corrosion by the liquid being pumped. Use care in selecting materials
to avoid galvanic corrosion at pump liquid end connections.
Use piping heavy enough to withstand maximum pressures. Remove burrs, sharp edges, and debris
from inside piping. Blow out all pipelines before making nal connections to pump.
Because vapor in the liquid end will cause inaccurate pump delivery, piping should be sloped up from
pump suction check to the supply tank to prevent formation of vapor pockets.
When pumping suspended solids (such as slurries), install plugged crosses at all 90°line turns to permit
line cleaning without dismantling piping.
See Figure 2-3 for a typical recommended pump installation scheme.
Figure 2-3:
General Piping

9
2.6.3 SUCTION PIPING CONSIDERATIONS
It is preferable to have the suction of the pump ooded by locating the liquid end below the lowest level
of the liquid in the supply tank.
To minimize the chances of a loss-of-prime condition, the pump should be installed as close as possible
to the supply vessel.
Avoid negative suction pressure conditions (suction lift), as such conditions adversely affect metering
accuracy. A lift of 2 meters of water column is the maximum permissible suction lift.
Series G pumps are designed to operate with process liquid supplied at or above atmospheric pressure.
Although these pumps can move liquids supplied at less than atmospheric pressure (suction lift), in
these negative pressure applications it is important that all connections be absolutely drip free and vac-
uum tight, and that a foot valve be installed at the bottom of the suction line (see upper left illustration of
Figure 2-2).
When pumping a liquid near its boiling point, provide enough suction head to prevent the liquid from
"ashing" into vapor when it enters the pump liquid end on the suction stroke.
If possible, use metal or plastic tubing for the suction line because tubing has a smooth inner surface
and can be formed into long, sweeping bends to minimize frictional ow losses.
A strainer should be used in the suction line to prevent foreign particles from entering the liquid end.
This and any other measures which prevent debris from entering and fouling the liquid end check valves
will give increased maintenance-free service. Check strainer frequently to prevent blockage which could
lead to cavitation. Keep suction piping as short and straight as possible.
Piping size should be larger than the liquid end suction tting to prevent pump starvation.
If long suction lines are unavoidable, install a stand pipe near the pump in the suction line.
Suction piping must be absolutely airtight to ensure accurate pumping. After installation, test suction
piping for leaks with air and soap solution.
2.6.4 DISCHARGE PIPING CONSIDERATIONS
Install pipe large enough to prevent excessive pressure losses on the discharge stroke of the pump.
Maximum pressure at the discharge tting on the liquid end must be kept at or below the rated pressure
(shown on the pump nameplate).
The pump will not deliver a controlled ow unless the discharge line pressure is 10 psi greater than the
suction line pressure. One way to create an articial pressure is the installation of a back pressure valve.
(Please contact your dealer for recommendations to increase back pressure in slurry applications).
When pumping water treatment chemicals directly into boiler drums, use one liquid end assembly for
each boiler drum. Discharging into a manifold having the slightest pressure difference between its
several discharge connections can diminish metering accuracy as the outlet with the lowest pressure
will receive more liquid than the other outlets.

10
2.7 VALVES
Back Pressure Valves
All metering pumps are prone to overpumping (excessive output) at low discharge pressures. To prevent this condition
from occurring, it is necessary to maintain approximately 10 psi (0.7 bar) back pressure against the pump. This can
be accomplished through the installation of a back pressure valve in the discharge line. Typically, the valve should be
located near the pump. However, back pressure valves for large pumps with long and extremely small discharge lines
may have to be installed near the point of discharge into the process (to minimize siphoning tendencies).
Pulsation Dampeners
An accumulator, surge chamber, surge suppressor, or pulsation dampener should be used with the back
pressure valve in the discharge line to absorb the ow peaks between the pump and the back pressure valve.
Without the pulsation dampener the valve mechanism will snap open and closed with the surge from each
pump stroke. The pulsation dampener will allow the back pressure valve to oscillate about a partly-closed
position, thus minimizing wear on the valve. Discharge line pulsation dampeners offer the further advantage of
limiting the ow and pressure variations characteristic of this kind of pump. Installing a properly sized pulsation
dampener will improve pump performance and may reduce system costs dramatically by permitting the
substitution of smaller piping. Please contact your dealer for further information on pulsation dampeners.
Safety Valves and Priming Valves
Motor-driven positive displacement pumps can develop excessive discharge pressure long before thermal overload
devices interrupt the motor electrical circuit. To prevent a blocked discharge line from causing damage to the pump,
piping, or process equipment, install a safety valve in the pump discharge line. This valve is designed and sized to
handle system ow rates and pressures safely while resisting corrosion by the process liquid.
To aid in pump start-up, it is advisable to install a priming valve on the discharge side of the liquid end.
Shut-off Valves
Provide shut-off valves in both suction and discharge lines next to the pump. Locate discharge line shut-off valve
downstream from the inlet connection of the safety valve. Figure 2-3 shows recommended valve locations.
2.8 ELECTRICAL CONNECTIONS
OPERATION WITH THE WRONG MOTOR ROTATION MAY DAMAGE THE PUMP AND MOTOR AND
VOID THE WARRANTY.
DO NOT FORGET TO CONNECT THE EARTH TERMINAL ON THE MOTOR TO THE EQUIPMENT
EARTH CONDUCTOR.
Ensure that the electrical supply matches the pump motor nameplate characteristics. Connect the motor in
accordance with the instructions and connection diagrams on the motor (or in the motor terminal box).
Note: Before operating the pump, check the direction of rotation of the motor to be sure it matches the direction of
the arrow on the motor fan cover (rotation should be clockwise when viewed from the top of the motor).
The electrical protection installed for the motor (fuse or thermal protection) must be suitable for the motor's rated
current.
CAUTION

11
Ground Ground
230V Delta Connection 380V Star Connection
Figure 2-4:
Terminal Connection for 3-Phase
Electrical Motor

12
SECTION 3 OPERATION
3.1 START-UP PROCEDURES AND CHECKS
Check that the pump is secured to its support.
If oil was previously removed for any reason, make sure pump drive has the correct volume (650 ml) of oil as below:
Recommendation oil:
Note: Equivalent oil of other brand is allowed.
Caution: Pump is required to stop running providing the surround temperature is below -10℃.
Make sure all isolation valves installed on the suction and discharge lines are open. If the discharge line is
equipped with an injection nozzle or a back-pressure valve, open the priming valve for discharge (if there is no
priming valve, disconnect the discharge pipe). This allows for verication that liquid is present in the liquid end
when the pump is installed in ooded suction condition. If the pump is installed in a suction lift condition, this
allows for priming of the pump during start-up.
Make sure that pump is set at 0% capacity.
3.2 CHECKING THE ELECTRICAL CONNECTION OF THE MOTOR
Start up the pump to check the motor's direction of rotation. It must comply with that indicated by the arrow
marked on the motor mount ange of housing (counter clockwise as viewed from the top of the motor). If the
rotation is incorrect, refer to Section 2.8 Electrical Connections.
3.3 START-UP
Once all the checks and procedures described above have been carried out, start the pump.
Conduct a visual and audio check of the pump (in particular, listen for the presence of any "suspicious"
noises).
Make sure that the stroke adjustment knob is unlocked.
Gradually increase the capacity until liquid can be seen owing from the priming valve. If no priming valve is in
place, when the liquid end is primed, the discharge check valves can be heard to be operating (should hear a
clicking noise caused by movement of check valve balls). When liquid end is primed, stop the pump and close
the priming valve.
Surround Temp.>-5 ℃Surround Temp.-10 ℃to -5 ℃
Model
MOBILGEAR 600 XP 220
MOBILGEAR 600 XP 68
Great Wall L-CKD220

13
Adjust the pump to the desired capacity. Lock the stroke adjustment knob (Item 320 in Figure 5-2).
3.4 CAPACITY CALIBRATION
After the rst 12 hours of operation, the pump may be tested and calibrated to nd the exact pump capacity
under specic operating conditions. Usually, calibrating the pump at only 100, 50, and 10 percent capacity
settings is enough to Indicate pump performance through-out the adjustment range.
The pump can be calibrated by measuring the decrease in liquid level pumped from a calibrated vessel.
This method is recommended for hazardous liquids because it eliminates operator contact with the liquid.
Calibration columns are available for convenient and accurate calibration of the pump. Contact your dealer for
more information.
THIS METHOD IS GENERALLY NOT RECOMMENDED AS IT MAY EXPOSE OPERATING
PERSONNEL TO HAZARDOUS LIQUIDS. FURTHERMORE, IF NO BACK PRESSURE IS
PRESENT ON THE DISCHARGE SIDE, THE PUMP MAY OVER-PUMP DRAMATICALLY IN WHICH
CASE THE POSITION OF THE CAPACITY ADJUSTMENT KNOB MAY HAVE LITTLE EFFECT ON
ACTUAL FLOW RATE.
FOR SAFETY REASONS, A CHECK VALVE IS RECOMMENDED FOR USE IN THE DISCHARGE
LINE NEAR THE POINT WHERE THE LINE ENTERS A HIGH-PRESSURE PROCESS VESSEL.
The pump can also be calibrated by collecting and measuring pumped liquid at the pump discharge port.
It may be necessary to create backpressure at the collection point to allow for proper pump operation (see
Section 2.7 Back Pressure Valves for recommendations).
WARNING
WARNING

14
SECTION 4 MAINTENANCE
4.1 PREVENTATIVE MAINTENANCE
Drive
Initially, change the oil in the pump drive assembly after the rst 1000 hours of operation. Thereafter, change
drive oil on an annual basis or after every 5000 hours of operation.
Drive oil: MOBILGEAR 600 XP 220 or Great Wall L-CKD220 (Surround Temp > -5 ℃), Qty: 650ml
Viscosity @ 40℃= 209 cSt
Viscosity Index = 95
ISO Grade =220
Diaphragm Assembly
The Series G Model M diaphragm should be replaced annually or every 5000 hours of operation to avoid the
possibility of failure. Refer to the instructions in Section 4.6 Diaphragm and Oil Seal Bellows Replacement.
Oil Seal Bellows
The Series G Model M oil seal bellows should also be replaced annually. Oil seal bellows replacement
requires the removal of the diaphragm assembly, so it is recommended that the oil seal and diaphragm
assembly be replaced at the same time. Refer to the instructions in Section 4.6 Diaphragm and Oil Seal
Bellows Replacement.
Check Valves
As in the case of the diaphragm, Milton Roy Company recommends that check valve balls, seats, gaskets,
and O-rings be replaced on an annual basis or every 5000 hours of operation. If highly corrosive material
(acids, slurries, etc.) is being pumped, more frequent replacement may be required. Complete instructions for
replacement of worn check valves are given in Section 4.5 Corrective Maintenance.
4.2 RETURNING PUMPS TO THE FACTORY FOR REPAIR
Pumps can not be accepted for repair without a Return Material Authorization. Pumps should be clearly
labeled to indicate the liquid being pumped. Process liquid should be ushed from the pump liquid end and oil
should be drained from the pump housing before the pump is shipped.
Note: A completed Material Safety Data Sheet (MSDS) must be packed in the shipping crate with any
pump shipped for repair. These safety precautions will aid the troubleshooting and repair procedure
and preclude serious injury to repair personnel from hazardous residue in pump liquid end. A Materials
Safety Data Sheet must accompany all re-turns.
All inquiries or parts orders should be addressed to your local representative or distributor.
4.3 ROUTINE MAINTENANCE
Milton Roy Series G pumps are carefully designed, manufactured, assembled, and quality tested to give
reliable service with minimal maintenance. However, a weekly maintenance check is recommended to conrm
proper operation of the pump.