o&m conctrolvalve
TRANSCRIPT
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USER’S MANUAL
This user’s manual corresponds to the
• Control valve model series 100,140,160.
• Pneumatic Positioner 820.
• Actuator series U - series andMSA Multi Spring Actuator
• FM Pressure Controller model 902.
Manufactured & marketed by
FORBES MARSHALL
A 34/35, MIDC Industrial Area,H Block, Pimpri, Pune 411 018 INDIA.
TEL.: 91(0) 20 7442020FAX. : 91(0) 20 7442040
E-MAIL : [email protected] SITE : www.forbesmarshall.com
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USER’S MANUAL2
Dear User,
Thank you for purchasing the FM Control Valve. Tomaximize your benefits from this product, we request youto read this manual thoroughly before installing the valve.A record of the product maintenance history should bekept every time our service representative visits you.
If you experience difficulty with theInstallation or operation of thisEquipment, please contact our nearestCustomer Service Representative
FORBES MARSHALL
USER’S MANUAL3
What’s Inside …
FM CONTROL VALVE
1. About The Product 8
2. Drawing of the Product 9
3. Principle of Operation 18
4. Getting Started 18
5. Before First Startup 19
6. Commissioning the Product 19
7. Maintenance 20
8. Assembly Tips 20Addition of packing ringsReplacement of Packing RingsReplacement of SeatReplacement of PlugRecommended Spares
9. Frequently Faced Problems 23 - 32
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PNEUMATIC POSITIONER 820.
1. About the Product
a. General Description 34b. Specifications 35c. Dimensional Drawing 36d. Technical Data 37e. Operating Principle 38
2. Getting Started
a. Installation & Commissioning 39
3. Operation & Maintenance
a. Basic Functions 40b. Calibration & Adjustment of Stroke 44
4. Trouble Shooting 45
5. Positioner part list 49
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ACTUATOR
1. Universal Diaphragm Actuatora. About the Product 52b. Principle of Operation 55c. Getting Started 57d. Installation 58e. Commissioning the Product 59f. Reversibility of Actuator 60
• Exchange of Spares• Mounting succession• Recommended Spares
2. Multi Spring Actuator
a. About the Product 64b. Principle of Operation 65c. Getting Started 66d. Installation 67e. Commissioning the Product 68f. Reversibility of Actuator 69g. Part List of MSA Actuator 70
3. Actuator Trouble Shooting 71-74
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PRESSURE CONTROLLER
1. About The Product
a. General Description 76b. Specifications 78c. Operation Principle 80d. Codification
2. Getting Started
a. Installation 81b. Mounting Instruction For Pressure Controller 82c. Pressure Controller Part List 85d. Commissioning 86
3. Operation and maintenance
a. Basic Function 88
4. Trouble shooting 90-92
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USER’S MANUAL7
FM CONTROL VALVE
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1. ABOUT THE PRODUCT:Specifications and Model Numbers
1 0 1 P 1 NUMBER OF STEPS FOR
• PARABOLIC PLUG• PERFORATED PLUG (L)• LOW NOISE CAGE (LK)• LOW NOISE DISC (LS)
TRIM TYPE• P :1 OR SEVERAL STEPPED PARABOLIC
PLUG• L :1 OR SEVERAL STEPPED
PERFORATED PLUG• LK :1 OR SEVERAL STEPPED LOW
NOISE PLUG• LS :1 OR SEVERAL STEPPED LOW
NOISE DISC
BONNET TYPE• 1 :STANDARD TOP FLANGE• 2 :TOP FLANGE WIYH DOUBLE GLAND
PACKING• 3 : TOP FLANGE WITH COOLING FINS• 4 :TOP FLANGE WITH BELLOW SEALING• 7 : STD. TOP FLANGE & PRESSURE
BALANCING• 8 : TOP FLANGE WITH COOLING FINS &
PRESSURE BALANCE
PRESSURE CLASS• 0 :NOMINAL PRESSURE CLASS(#); #150,#300 TOP GUIDED PLUG• 1 :NOMINAL PRESSURE CLASS(3); #600,#900 TOP GUIDED PLUG• 4 :NOMINAL PRESSURE CLASS(#); #300 TOP & BOTTOM GUIDED PLUG• 6 :NOMINAL PRESSURE CLASS(#);
#600, #900 TOP & BOTTOM GUIDED PLUG
• SINGLE SEAT CONTROL VALVE
This manual is applicable to the following valve model nos.:100, 140 & 160 The code no’s are given above.
For ex. : Valve with model no. 1 0 1 L 2 : SINGLE SEAT CONTROL VALVENOMINAL PRESSURE # 600-900 STANDARD TOP FLANGE WITH TWOSTEP PERFORATED PLUG.
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2. DRAWINGS OF THE PRODUCT:
Following are the sectional drawings elaborating salient features of FM controlvalves. These are two different series distinguished by 3-flanged and 4-flanged design of FM bodies.
The index of drawings is as follows:
NO. DWG NO. VALVE TYPE
1 I/A CONTROL VALVE SERIES 141
2 I/B ON/OFF VALVE SERIES 141
3 I/C ON/OFF AND CONTROL VALVE SERIES 141 WITH SOFT SEATING
4 I/D TOP FLANGE WITH COOLING FINS SERIES 143
5 II/A CONTROL VALVE SERIES 101
6 II/B ON/OFF VALE SERIES 101
7 II/C ON/OFF AND CONTROL VALVE SERIES 101 WITH SOFT SEATING
8 II/D TOP FLANGE WITH COOLING FINS SERIES 143
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BOTTOM FLANGE
GLAND NUTSLOTTED NUT
GUIDE BUSH
GLAND FOLLOWER
BOTTOM RING
VALVE BODYTOP FLANGE
DESCRIPTION
SPRING DOWEL PIN
GLAND PACKING RINGS
BALLSPINDLE
SEATPLUG
1I.NO.
1110
6
432
5
9
78
BOLT
GASKET
NUT
121314151617
CONTROL VALVE-SERIES 141
FIG. I/A
5
14
173
16
14
712
1011
13
16
17
2
815
6
14
9
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ON/OFF VALVE SERIES 141
GLAND PACKING RINGSGLAND FOLLOWER
DESCRIPTION
BOTTOM FLANGE
SPRING DOWEL PIN
1I.NO.
65
32
4
11
910
78
VALVE BODY
BOTTOM RING
TOP FLANGE
SPINDLEBALLPLUGSEAT
1716
131415
12 GLAND NUTSLOTTED NUTGASKET GUIDE BUSH
BOLTNUT
5
FIG. I/B
14
317
14
16
7
2
14
158
6
17
9
12
1011
16
13
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10 GLAND PACKING RINGS
LOWER PARTO-RINGUPPER PARTSPRING DOWEL PIN
SPRING DOWEL PINSPINDLE
BOTTOM RING
TOP FLANGEVALVE BODY
DESCRIPTION
BOTTOM FLANGE3
I.NO.12
SEATPLUG
5.1
45
5.35.2
BALL7
5.46
89
GASKET SLOTTED NUTGLAND NUTGLAND FOLLOWER
GUIDE BUSH
1716
1211
1413
15NUT BOLT
5
CONTROL AND ON/OFF VALVE SERIES 141
WITH SOFT SEATING
FIG. I/C
14
173
4
161
5.35.4
5.2
2
8
15
5.1
6
17
14
13
16
9
1110
127
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4 SEAT TOP FLANGE WITH COOLING FINS
I.NO.123
TOP FLANGEVALVE BODY
BOTTOM FLANGE
DESCRIPTION
SERIES 143
FIG. I/D
GLAND PACKING RINGS
12
8
65
7
109
11
16
1413
15
17
GLAND NUTGLAND FOLLOWER
BOTTOM RINGSPRING DOWEL PINSPINDLEBALLPLUG
GUIDE BUSH
SLOTTED NUT
NUT
GASKET
BOLT
14
173
16
1
4
6
5
15
17
8
14
7
162
10
913
1112
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1716
1413
101112
87
54
6
9
15
21
I.NO.
3
SLOTTED NUT
BOTTOM RINGGLAND PACKING RINGS
SPRING DOWEL PIN
GLAND FOLLOWER
GUIDE BUSH
TOP FLANGEVALVE BODY
DESCRIPTION
PLUGSEAT
SPINDLEBALL
NUT BOLT
GASKET
GLAND NUT
CONTROL VALVE-SERIES 100
FIG II/A.
5
14
7
2
815
6
14
17
13
16
9
12
1011
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ON/OFF VALVE SERIES 101
SLOTTED NUTGLAND NUT
BOTTOM RINGGLAND PACKING RINGS
SPRING DOWEL PIN
GLAND FOLLOWER
GUIDE BUSH
TOP FLANGEVALVE BODY
DESCRIPTION
11
I.NO.1
PLUGSEAT
BALLSPINDLE
6
32
54
87
109
BOLTNUT
GASKET
16
141312
15
17
5
FIG. II/B
1
4
7
2
8
6
15
1714
9
16
13
1110
12
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5.2
3
I.NO.
21
5.1
45
10
6
5.35.4
789
14
111213
15
1716
UPPER PARTSPRING DOWEL PIN
BOTTOM FLANGE
VALVE BODYDESCRIPTION
TOP FLANGE
SEATPLUG
SLOTTED NUT
BOTTOM RING
LOWER PART
SPRING DOWEL PIN
GLAND PACKING RINGSGLAND FOLLOWER
SPINDLE
O-RING
BALL
GUIDE BUSHGASKET
GLAND NUT
NUT BOLT
CONTROL AND ON-OFF VALVE SERIES 101WITH SOFT SEATING
FIG. II/C
5
6
5.4
14
5.1
15
5.3
5.2
1417
8
2
11
13
16
10
9
127
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4 SEAT TOP FLANGE WITH COOLING FINS
I.NO.123
TOP FLANGEVALVE BODY
BOTTOM FLANGE
DESCRIPTION
SERIES 143
FIG. I/D
GLAND PACKING RINGS
12
8
65
7
109
11
16
1413
15
17
GLAND NUTGLAND FOLLOWER
BOTTOM RINGSPRING DOWEL PINSPINDLEBALLPLUG
GUIDE BUSH
SLOTTED NUT
NUT
GASKET
BOLT
14
173
16
1
4
6
5
15
17
8
14
7
162
10
913
1112
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3. PRINCIPLE OF OPERATION:
The Control Valve type mentioned above are according to ANSI B 16-34. They reduce the pressure/ flow by single step or multi step parabolic plugor perforated plug. By changing the valve lift (plug position) the annular areabetween the plug and seat changes, which in turn changes the flow. The ‘flowcharacteristics’ is determined by the profile or the size and orientation of theholes in case of perforated plug. At zero lift (closed position of the controlvalve) the plug taper rests on the tapered edge of the seat and thus providesmetal to metal closing. In case of multi-step parabolic plugs, only last step hastaper; which rests on the seat in closed position.
4. GETTING STARTED:
Installation
The place of installation should be selected to have sufficient valveaccessibility around the valve for dismantling & repairs.
Valve size 6” and above should have sufficient space above the valve tomount a chain pulley block.
When valves are mounted in raised position platform should be provided atleast on one side of the valve.
The valve with flanged ends can be directly installed in the pipeline withflanges. The valves with welded ends can be directly welded in the line. Inboth cases following points must be considered:
a) The valve should be in a horizontal position, with valve spindle in verticalposition as shown in cross-section drawings of valves in next section.
b) The upstream & downstream of the valve should be properly supported toavoid excessive stress on the valve body.
c) On upstream & downstream of the control valve there should be a straightflow at least 10x valve size (in mm) without any interruption by stop valves,elbows.
d) To avoid longer breakdown of the plant a bypass should be installed.
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5. BEFORE FIRST STARTUP:
All the main lines as well as the pneumatic lines are to be thoroughlyflushed before first commissioning. Following points must be taken careduring flushing of these lines: -a) During flushing flanged control valves should be taken off the line and
replaced by a spacer i.e. spool piece.b) If the valve is welded in the line all internal parts including top and bottom
flanges have to be removed and top & bottom flanges should be blankedwith specially ordered blanked flanges. Dismantling and assembling of thevalve internal should be carried out as per procedure given in TROUBLESHOOTING.
c) If the flushing is done with the assembled valve inline the valve must bedismantled & cleaned thoroughly after flushing. Special attention to begiven to all hollow spaces and gaps.
d) Parts which have been corroded by the pickling /cleaning process have tobe repaired or replaced. Specially take care of probable leftover of picklingfluid in stuffing box area.
6. COMMISSIONING THE PRODUCT:
Please refer to drawing no I/A to I/D and II/1 to II/D.
At the first startup, the gaskets (14) may leak due to setting. If so the nuts (16)should be tightened equally and evenly. Also there may be leakage throughgland packing (10) due to setting of packing rings by pressure andtemperature effect. Therefore, tighten the gland nut (12) slightly. Thistightening of gland nut must be done just sufficient to stop leakage. Excessivetightening will increase friction between packing rings (10) and spindle (7) willresult in bad control quality.Control valve in steam line with high temperature should be slowly heated upbefore startup to avoid thermal shocks.
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7. MAINTENANCE:
GENERAL
The valve spindle (7) must be kept clean in places with bad environmentalconditions. The cleaning should be done when the valve spindle is in the upmost position.
ROUTINE MAINTENANCE
As a part of routine maintenance it is only necessary to retighten the gland nut(12) if any leakage through gland packing starts. Also it may be necessary totighten the nuts (16) on top and bottom flanges if the gasket (14) leak due tochanging pressure and temperature.
8. ASSEMBLY TIPS:
• ADDITION OF GLAND PACKING RINGS
If, the leakage cannot be stopped, by re-tightening of the gland nut it will benecessary to add one or two packing rings. For this the valve should bepressure-less and drained. Remove the lift indicator coupling. Take theactuator spindle in uppermost position and lock it there. Unscrew the glandnut and lift the gland follower (11) out. Graphite rings can now be slipped overthe spindle and pushed down in stuffing box with the help of gland follower(11).
Endless pure graphite rings can also be carefully cut in two halves and laidaround the spindle so that the broken faces match again. Push down the ringin the stuffing box with the help of gland follower. In this case the lift indicatorcoupling need not be removed.
• REPLACEMENT OF GLAND PACKING RINGS
The valve must be pressure-less and drained. Dismantle the lift indicatorcoupling between valve and actuator spindle.
Unscrew the slotted nut (13) and actuator can now be taken out. Now loosenthe nut (16) of top flange. Unscrew th0e gland nut (16) & gland follower (11)can be lifted up. Care should be taken while lifting removing top flangeespecially in steam & hot gas piping as slight leakage in any stop valve canpressurize the control valve. After ensuring that the valve is pressure-less thetop flange along with the plug-spindle assembly can be completely taken off
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the body. Take out the old packing rings (10) with the help of a hook. Alsotake the bottom ring (9) out of the stuffing box.
Clean all the parts of stuffing box including all the threading. Also clean thetop flange in the guide bush (15) area and gasket (14) area. Smear all partswith Molykote HSC or molybdenum disulfide grease.In some special cases say with inflammable fluids this grease cannot be useddue to chemical reaction.Clean gasket-seating area in body. Use a new gasket (14).Apply Mo-S2 grease to gasket also. Carefully place the plug spindle assemblyon seat (4). Place the top flanges on the valve body. Smear bolt threads withMo-S2 grease and tighten the nuts equally and evenly.
Insert bottom ring (9) in stuffing box bore. Push packing ring around the valvespindle. Take care that the oblique cuts on the rings are staggered.Finally assemble the gland follower (11) and gland nut (12). Connect valvespindle with the actuator spindle using lift indicator and start the process.(Refer to commissioning the product).
• REPLACEMENT OF SEAT
The seat is replaceable as it is screwed in the body. Actuator, Top flange,Plug & Spindle assembly should be dismantled according to previous section.
A special tool can be used to unscrew the seat. Smear the threads of the newseat with Mo-S2 grease (with the exception of some special fluids).Screw in the new seat with the special tool. Reassemble the seat asexplained in REPLACEMENT OF GLAND PACKING RINGS.
For screwing & unscrewing of the seat, especially in case if larger valve size itis recommended to use pneumatic tools.
• REPLACEMENT OF PLUG
Dismantling actuator top flange and plug spindle assembly as described inREPLACEMENT OF GLAND PACKING RINGS. It is recommended toreplace complete plug spindle assembly instead of plug assembly. Assemblyof new plug spindle can be done as described above.
• RECOMMENDED SPARES
It is recommended to keep following spares in stock: -
1. Seat and plug spindle assembly. (Part no. 4,5 and 7.)2. Set of gaskets. (Part no. 14)3. Set of gland packing rings. (Part no. 10)
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** 1) No foreign material should enter the line.2) No Sulfur or corrosive material should enter SS
410 tubing.3) Check the direction of valve as per arrow marking
on body and side flange.4) Every time the valve is disassembled, calibration
must be done.5) The valve should be mounted in vertical position
only. Other wise the forces due to weight ofmountings will come on the trim.
6) No hammering or anything that will distort theoriginal shape/design of any of FM productshould be done on trial basis.
7) Air quality is very important for any valveoperation. Please keep it checking intermittently.
8) In case of PRDS valves water quality should alsobe controlled. Strainers can be inserted ifrequired before the water control valve.
9) Ensure correct air tubing connections.10) The valve should be mounted safe so that, it
remains free from water, fluids, etc. accumulatingon its outer surface.
11) Any measuring gauge should be inserted onlyafter minimum 1 m from valve that it gives correctreading on steady flow. * For Roboter controlledvalves this is very significant.
12) Avoid mishandling to prevent damage of delicateparts and mountings like gauges.
13) It is always recommended to have valve supportsplaced at site for bigger valves.
14) Refer the manual while changing the spares
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9. FREQUENTLY FACED PROBLEMS
Q1] How to assemble or disassemble valve?
A] Valve assembly procedure:
A1.1] Refer the Data Sheet; ensure that all componentsreceived as per the same. Read the additionaldescription carefully and take note of any specialrecommendations like degreasing, etc.
A1.2] Deburr and clean all the components.
A1.3] Clean and dry plug, spindle with air.
A1.4] Plug and spindle assembly:a] Hold the plug in the vice using Aluminum or soft pads.
Drop the ball of correct diameter into the top bore of theplug.
b] Screw the spindle until it touches the ball.c] Check the fitting by removing the plug-spindle assembly
from the vice and holding it horizontal in quicksuccessions. If the spindle is not tight the ball will make asound. Then tighten the spindle.
d] Again hold the plug in vice using Aluminum or soft padsand remove spindle and ball.
e] Apply ‘Molycote HSC’ to ball and spindle threading andtighten fully, as explained above.
f] Drill diameter 4mm hole in the plug assembly and fit thedowel pin in the assembly. Use correct drilling jig forabove purpose
g] Check the plug for true on either lathe or on V-block andusing dial gauge.
A1.5] Clean the top flange and bottom flange in the tank andrinse with water and then dry with air. Press fit the guidebush, ensuring that the edges are not damaged. Punchholes using the punch on the top flange around the guidebush.
A1.6] Hold body in fixture (up to 50 NB) and dry with air. Rotatethe body such that bottom flange is facing upwards.
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A1.7] Apply Molycote HSC on the gasket face and on bothsides of the gasket. Fit the bottom flange on the bodyand tighten evenly/squarely.
A1.8] Now reverse the body such that the topflange is now upside.
A1.9] Apply molycote on seat threads and taper portion.Ensure that there is no damage to the seat-taper in thebody. Match the seat and body taper first using color bylightly screwing the seat inside the body. Using propertightening tools and pneumatic gun.
A1.10] Apply Molycote HSC on the gasket face and both sidesof the gasket.
A1.11] Place the plug-spindle assembly in the body and slidedown the top flange on to the body. Tighten the topflange evenly/squarely.
A1.12] Place bottom-ring in the top flange and add gland-packings. Compress the gland packing by fitting thegland follower and tightening the gland nut.
A1.13] For valves up to 50NB, check for seat leakage on thebench rig using pneumatic supply. Apply force on thespindle using toggle clamp. Check for leakage byisolating the air supply and observing the pressure dropon the gauge and soap-water solution. Carry out lapping(360 degrees). If there is leakage, then retest the valve.
A1.14] All valves should be tested for seat leakage on thehydraulic test bench after mounting Actuator.
A1.15] Actuator mounting:
a] Mount the actuator on the support and tighten the screw.b] Place the actuator on the top flange and tighten theslotted nut using the special spanner.
c] The actuator spindle should be lifted slightly and couplewith the valve spindle using lift-indicator
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d] Set the Actuator (as per Data Sheet) by tightening theadjustment bolt.
A1.16] All valves to be tested hydraulically. The valve assemblyshould be mounted on the test bench. The spindle shouldbe raised fully either by hand or by actuator. The valveshould be filled with water and all air should be ventedfrom the valve. This is done, by loosening the gland nut.
A1.17] The valve should be pressurized depending upon itsclass as per the chart displayed in the testing area. ForIBR approved valves, the testing pressure should beminimum twice of the working pressure as per the IBRschedule. The valve should be pressurized for minimumof 60 seconds for sizes up to 200NB and 180 seconds for250NB. The hydraulic test should always be carried outin the unpainted condition.
A1.18] The hydraulic seat leakage test should be done, byclosing the valve and pressurizing the inlet side of thevalve. The seat leakage pressure should be as per theVDS and amount of leakage shall be compared with theseat leakage chart for permissible leakage displayed inthe assembly area. If the leakage is more than thatspecified in the chart, lapping should be done.
A1.19] Note all recordings. (Including the corrective action.)
Q2] How to mount actuator on the valve?
A2.1] Fix actuator support on the valve body.
A2.2] Fix the actuator (as per the requirement i.e. air to close/air to open) on the support and valve body assembly.
A2.3] Fix lift indicator to the actuator spindle.
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Q3] What is the sequence of other mountings?
A3.1] Fix Positioner link to lift indicator and mounting bracket.
A3.2] Fix threaded pin on Positioner and Positioner on thevalve assembly.
A3.3] Fix AFR bracket.
A3.4] Fix gauge group.
A3.5] Fix AFR on AFR bracket.
A3.6] Fix the ferule.
A3.7a) Cut the tube.b) Flatten the tube.c) Mark for bending.d) Bend the tube.e) Fix the tube to the actuator, Positioner and valve.
A3.8] Fix the arrow after deburring.
A3.9] Do the calibration.
Q4] How to do the valve hand-wheel assembly?
A4.1] Deburr and clean all the components.
A4.2] For air to open assembly:a] Assemble supporting disc and Teflon disc in bush well
with lock ring.b] Assemble bush with hand-wheel support. Lock using M8
grub screw.c] Press fit dowel pin with clamp rings.d] Assemble hand-wheel, castle nut on the spindle.e] Pass spindle through the bush and spindle clamp ring
with spindle by locating the dowel pin in the slot providedon the support.
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f] Pass spindle through the hand-wheel once for checking.
For air to close assembly:a] Assemble threaded bush with support and lock using M8
grub screw.b] Assemble threaded nut, lock nut and castle nut with
spindle. Pass spindle through bush.c] Check by passing spindle through bush.
** How to flush the valve?
Before charging any steam-line or any of the piping ofPressure Reducing and / or De-superheating Stationsand /or before taking control valves to auto or manualmode the line must be thoroughly flushed. However themethod of flushing defers as per the type of valveconnections. Let us see one by one.
a] For flanged type of valves:1] After all type of fabrication work is over, the total valve
with body is to be ‘dropped’. (I.e. to be taken out of theline is kept wrapped at a place away from the line toavoid any damage from the flushing media beingfollowing on it.)
2] Now the line can be charged with the operating mediai.e. steam, water, etc. as per the application may be. Ifthe media is to be prevented from wastage a spool-piececan be assembled at the place of FM valve otherwise it isbetter to charge the line open to atmospheric pressureand high velocities, so that all the weld spots, foreignparticles, rust in the line is washed away. This procedurecan be followed for 20-30 minutes.
3] For better results and assurance flushing can berepeated for 3 to 4 times.
b] For butt-welded valves:1] For butt welding TIG [Tungsten Inert Gas Method should
be adapted at the root. This avoids oxidization and slagproblems.
2] Stress relieving should be done at all inlet and outletwelding places.
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3] After all these precautions for flushing the line the wholevalve assembly should be taken out of the welded body.The procedure is as follows:
3.1] Open the valve up to 15 – 20% by means of thehand-wheel or air.
3.2] Now the nut and bolts connecting the body and topflange can be diagonally unscrewed withequal torque. The top-flange assembly or say thebonnet assembly should be taken out verticallyupward only and not side-ways.
3.3] Now the line can be charged with the operatingmedia i.e. steam, water, etc. as per the applicationmay be. It is better to charge the line open toatmospheric pressure and high velocities, so thatall the weld spots, foreign particles, rust in the lineis washed away. This procedure can be followedfor 20-30 minutes.
It is recommended to replace the seat with thedummy seat [which is provided with the valve andhas maximum kV in its size and pressure class]before flushing.
Q5] What are various torque values for assembling?
THREAD SIZE TORQUE MOMENTN-m
M8 10M10 16M12 30M16 70M20 100
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Q6] What to do if the seat is not coming out of thebody?
6.1] Proper tool has to be fabricated for this purpose.6.2] Heat the seat only using gas flame. This is to be done to
relieve stresses due to various operating parameters andrusting between seat and body.
6.3] Suddenly put cold water on the seat and immediatelyunscrew using the special tool.
** In such cases it is always recommended not to doanything on trial basis and call our service engineer.
Q7] What to do if the valve output is pulsating, i.e. thevalve is hunting?
The valve may hunt in operation and at rest also.7.1] Reasons for hunting:
a. Presence of oil, dust, foreign material in the piston-cylinder assembly of Positioner.
b. Over tightening of gland.c. Air leakage in actuator or air tubing.d. In case of valve with silencer basket. The basket
might have shifted from its place i.e. its screws areloose or the basket might have damaged.
7.2] Effects:a. Valve not functioning.b. Pulsating output.c. Plug/seat may even (in case if severe hunting)
break.7.3] Remedies:
a. Air should be free from oil, dust, and moisture.b. Open piston-cylinder assembly (ref. Pos. manual
2.2) and clean with thinner or any fluid that will notaffect the material of o-rings, etc.
c. Check for consistency of air supply.d. Make loose the gland by unscrewing the gland nut
slightly. Clean the spindle. Apply lubricant to thespindle surface.
e. Arrest the air leakage in tubing. Put Teflon tape atferrule.
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USER’S MANUAL30
f. Take care that any Sulfur fumes or caustic aciddoes not enter the tubing. When there is suchmaterial used in the plant for any purpose it is saferto use SS 316 tubing.
g. For silencer basket valves tighten the basketscrews, and in case of damage to basket itselfreplace it with new one.
Q8] If the valve is passing, or say due to any otherreason need arises to check the seat leakage, thenhow to do it?
8.1] Ensure that the valve is fully closed and there is no signalfrom the actuator.
8.2] Pass the flow medium through the valve inlet.8.3] Check for output through the valve. Measure at the flow-
meter/drain at outlet.8.4] Compare with the allowable values.8.5] If the valve is butt-welded the take the measuring
opening the line after the spool piece next to the controlvalve.
Q9] If the valve with pressure balance rings passesheavily what are the possible reasons?
The possible reasons are as follows:a) Pressure balance ring has worn out.b) Foreign material stuck at the plug-seat interface.c) Passing through seat and body.d) Due to loss of stiffness of springs in actuator.e) Oil or dust in Positioner.f) Disturbed zero setting.
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Q10] If the pressure balance ring is damaged then howto replace it?
10.1] In this case the plug-spindle assembly is to be taken out.Follow strictly as given:
a. Open the valve 15%. Lock the hand-wheel toprevent further opening.
b. Remove the tubing, Positioner and all othermountings.
c. Disassemble the lift indicator.d. Unscrew the nut bolts (diagonally) holding the body
and top/bonnet. Lift the actuator top vertically up. Itshould be done neatly ensuring the movement ofspindle to be perfectly vertical without touchinganything.
e. Now keep the removed assembly such that theplug does not touch the ground or catches anyforeign material.
f. Unscrew the Allen bolts of the plug.
Q11] If leakage found in soft seated valve i.e. valve withplug having two halves, and the o-ring of plugfound damaged then how to replace it?
11.1] First of all find out the reason for leakage as follows:a) Give 4-ma signal to Positioner. The output of
Positioner should be zero and the valve should beperfectly close. If it not like that then Positionertroubleshooting is to be done.
b) Valve might have been lifted manually by hand-wheel close it.
c) While servicing the coupling i.e. lift indicator is notfitted properly. Re-couple it properly as follows:1. Remove coupling. Insert spacer ensuring
that the plug is completely seating on theseat. Re-couple.
d) Plug might have damaged. If it is the case:
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USER’S MANUAL32
1. If it is standard parabolic single piece plugthen for small damage, lap the plug andcheck for leakage and if severe damage isfound then the plug is to be changed.
2. If it is soft-seated plug, then it has two halvesas bottom cone and top cone and an o-ringbetween both of them. This o-ring getsdamaged. Replace that with new.
e) The seat might have damaged. In this case take asmall cut from the degree at the bore of seattowards periphery. Ensure that the cut onlyremoves the affected material and not goes further.
** Take care to flush the valve every time it isdisassembled and no foreign material enters thevalve.
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USER’S MANUAL33
FM PNEUMATIC POSITIONERMODEL 820
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FIG. 1
1. ABOUT THE PRODUCT:
a. General Description:
The Positioner acts according to the force balance principleand proportionally controls the position of the control valve.By changing the cam curve the signal v/s strokecharacteristics of the Positioner can be changed. Thedirect/reverse function of the Positioner; can be selected by,changeover switch position & cam side. Further alternativesare also foreseen, for operating with input signal split range.The unit is also provided with gauge group. The mounting ofcontrol valve is made according to NAMUR.
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Specifications:
Basic type no. 820 x x x x x x
Input signala. 0.2-1.0 barb. 0.0-20.0 barc. 4.0-20.0 bar
Air SupplyRequired a. 1.2-6.0 bar
b. 1.6-6.0 barc. 1.8-6.0 bard. 2.0-6.0 bare. 3.0-6.0 barf. 4.5-6.0 barg. 6.0 bar
Air Filter Regulatora. with AFRb. without AFR
Bypassa. With bypassb. without bypass
Gauge groupa. With gauge-groupb. Without gauge-group
Actiond. Direct actionr. Reverse action
Model number820. Pneumatic824. Electro-Pneumatic827. Electrical
Special design:For stroke ranges, less than 10 mm and more than 100 mm forcam angle 90°, by mounting an I/p module the PneumaticPositioner may be changed to an Electro-pneumatic one at anytime.
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137
60 30°
220
30°
Main Dimensions of Positioner 820
120
120
21
220132
1/4" NPT
M8
132
30°
30°
137
60M8
TOTAL VIEW OF POSITIONER WITH GAUGES:
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USER’S MANUAL37
d. Technical Data:
Input : 0.2-1.0 bar
Split range : 0.2-0.6 & 0.6-1.0 bar
Output : 0-air supply pressure
Air supply pressure : max 6 bar
Open loop gain : max 100
Internal air consumption : @0.5 m^3/h (0°c, 1 bar Abs)
Air capacity : 5m33/h(0°c, 1 bar abs) at 1.4
Hysterisis : 0.7 % of range
Threshold response : 0.5% of rangeDependence on air supply
Pressure : 0.1%/0.1 bar deviation
Vibration stability : 10sg DIN89011
Operating temperature : -20 to +60 °c
Direction of control effect : Field reversible[Factory setting is direct acting.]
Connection : ¼” NPT
Stroke range : 20-100 mm
Weight : basic unit- 1.7 KGGauge set- 0.5 KG
Protection class : IP 54
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USER’S MANUAL38
EN4
Ventilation
output 0
Valve
Single -acting positioner
16 10 20 13 11
5 8 4
I
A
S
FIG. III
e. Operation Principle:
As already mentioned the Positioner acts on the force balanceprinciple (fig iii). The pneumatic signal fed into the input I exerts aforce on the diaphragm in the diaphragm chamber (5). This force iscompared with the feedback force of the spring (10). In balancedcondition the Positioner remains in steady condition. When theinput pressure increases the piston lever (8) is deflected upwardsand the piston (4) is lifted. Now, the supply air flows through theoutput ‘O’ into the pneumatic actuator, whereby the ‘valve actuatorspindle’ is displaced (in present case downward). The initial springtension of the spring (10) is increased via the stroke scanning lever(16). This happens until the spring force balances the diaphragmforce (i.e. steady condition).
The actuator stroke thus follows the input signal according to theshape of the cam. In case of falling input signal the effect on valvestroke is reversed. The piston moves downward, turns off thesupply air and ventilates the actuator via the exhaust hole inchange over switch. Thereby the Actuator changes its positiontowards the original position.
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USER’S MANUAL39
2. GETTING STARTED:
a. Installation & Commissioning:
Before connecting and adjusting the Positioner the action of theoutput signal and the signal/stroke coupling (position of cam), i.e.the control characteristics should be checked. In case every thingis in accordance with the requirements the connecting & adjustingexercise can be started otherwise a change of curve or aninversion, be made.
Depending upon the cam side N or I, visible on the installed cam(13) the spring wire (54) is set into the link (52), according to fig.IV.The link (52) prepared this way is fixed to lift indicator (71) with twono of socket head screws M6 (57). The stroke screw is set on thedesired lift marking on the scanning lever. Thereafter, themounting bracket (51) is fixed to the Positioner with two no of hex.Screw (55). Then the mounting bracket (51) and the Positioner areplaced in such a way, that the cylindrical part of the strokeadjustment screw (53) grips into the slot of the link (52). Finally themounting bracket (51) is fixed to the support (74) using a hexscrew M8 (55) and spring washer (67).
Fig VI shows the mounting arrangement. Unevenness of thecasting at the yoke (74) causing an inclination of the mountingbracket (51) and thus of the Positioner can be compensated withthe oblong holes for the Positioner fixing on bracket.
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3. OPERATION & MAINTENANCE:
a. Basic Functions:
Split range: Split ranges are used in cases such as twodifferent ‘control valves’ are to be controlled by a singlecontroller operating in different ranges. Then one valve wouldoperate in input range of 0.2 to 0.6 bar and the other in therange of 0.6 to 1.0 bar. To identify the different springs (10) forthe split range we have marked them with the following colors:RED corresponds to 0.2 to 0.6 barYellow corresponds to 0.6 to 1.0 bar
Direct/ reverse action: for changing action of Positioner (reffig IX) which is stuck inside the cover. Depending upon therequired action (direct or reverse) and also on the type ofactuator (air to open and air to close) the changeover switch (6)or the cam (13) side or both of them must be changed. Thechangeover switch can be turned into other position by slightlyloosening its clamping screw. However before inversion of camall the air connections have to be pressure-free in order to hangthe feedback spring (10) out of the eye of the feedback lever(11) by means of a screwdriver. Now, the clamping screw (35)of the cam is entirely drawn out, the cam removed, turn and setit again with the desired curve downward. Subsequently, theclamping screws have to be tightened again and the feedbackspring set in again.
1. Calibration adjustment of stroke: before changing curve allair-connections have to be pressure-free in order to hang thefeedback spring out of the eye of the feedback lever by meansof a screwdriver. Thereafter the clamping screw of the cam isplaced in again with the desired curve downward and carefullyfixed with the clamping screw. Finally the feedback spring mustbe hung again. The correct choice of curve can be made usingthe middle part of the adjustment table (fig IX).
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Position of Spring Wire in the Carrier
For Cam Side N
For Cam Side I
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NAMUR mounting parts
55
67
51
53
5856
57
5452
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Input increasing, Output decreasing
Input and Output increasing
321
N
I
1
23
I
I
N
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b. Callibration And Adjustment Of Stroke
The lower part of the connections and adjustment table (inside thecover) indicates the air connections of the single acting and doubleacting Positioner. After doing the connection the adjustment of thestroke can be made. For this the input signal is first adjusted to50% corresponding to 0.6 bar at signal range 0.2 to 1.0 bar. Incase the stroke scanning lever (16) is not in horizontal position, theadjusting screw for zero setting (20) is to be displaced accordingly.
In case of horizontal position of the stroke-scanning lever the liftindicator (fig 71) points to the center of the stroke. Otherwise thefixing screw (55) of the mounting bracket (51) must be displacedaccordingly and the screw is tightened again.
By variation of input signal now both end positions of the valvestroke must be entered. Both input signals at the end position haveto differ from each other by exactly 0.8 bar (for instance valve shut0.15 bar valve 100% open 0.95 bar). In case of variation from thisrequired position, the stroke adjustment screw (53) is loosenedand moved within the slot of the stroke-scanning lever to increaseor decrease the value as required. Afterwards the strokeadjustment screw is fixed again and the pressure difference of theend positions is checked. If necessary the procedure is repeated.After having made the required adjustment to get the pressuredifference of the input signals the adjustment screw for zero setting(20) can be adjusted in such a way that the locking position(closed) of the valve corresponds to the desired input pressure(0.2 or 1.0 bar). In the above example the adjustment screwshould be slightly tightened in order to reach 0.2 bar as the lockingposition pressure.
• We have described the stroke position for the most usualversion only:Output signal increasing input signal i.e. change-over-switch atN and cam side I characteristic to curve no. 1 input signal range0.2-1.0 bar corresponding to 0%-100%.
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4. TROUBLE SHOOTING:
1. How to calibrate valve with Positioner?
1.1] Make pneumatic connections as shown on the plate pastedinside the Positioner cover.
1.2] Ensure that there is no leakage at joints. Also check ferrulefor damage. Put Teflon on the Ferrule if damaged.
1.3] Set the desired AFR pressure as mentioned on the plate.1.4] Open the cover [47] by removing all screws [48](4no.s)1.5] Ensure that air is dry and free from oil/dust. To check the
quality, of air drain the AFR by pressing the drain-valve atthe bottom of AFR. If there is any oil or dust stop the nextprocedure and ensure supply of quality air.
1.6] Set the stroke adjustment screw [53] as per the valve liftnumber given on the scale on the stroke scanning lever [16].
1.7] Give signal of 4mA from I/P to the Positioner. Ensure 0.2 kgis available, in the topmost pressure gauge. Check the valvelift. It can, be seen on the scale by the lift indicator at thecoupling between valve and actuator.
1.8] If the valve lifts, bring it back to zero lift position (valve fullyclosed) by brining the zero adjusting screw (20) at zerosetting.
1.9] Give signal of 20mA from I/P to the Positioner. Ensure 1 kgis available. Check the valve for fully open condition. If itis not fully open; then make it by adjusting the strokeadjusting screw [53].
1.10] Again, check for zero setting and full lift setting alternately byrepeating the above procedure.
1.11] Finally the valve should automatically close at 4mA signaland be full open at 20ma signal. Achieve check the valve atintermediate input signals for its corresponding lift.
1.12] If still, desired results are not achieved, bring the valve to fullclose position by loosening the slotted screw [29].(Check the position of piston-lever [8] by twisting it up anddown. This helps in adjusting the zero setting by removingany misalignment of piston inside the cylinder.)
1.13] If the valve is still short of travel, unscrew the threaded pin[17] fully, put a washer and retighten it.
* The signal from I/P should be completely cut while removingthe threaded pin; otherwise the diaphragm assembly willburst.
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USER’S MANUAL46
1.14] Reassemble in the reverse manner.2] If Positioner is, out of calibration what needs to be
checked/replaced?
2.1] Diaphragm chamber assembly: Open the Positioner coveras discussed in above problem. Connect full signal of 20mafrom I/P. Spray soap solution on the diaphragm chamberassembly. *Ensure the soap solution does not enter thepiston cylinder assembly. If there is any puncture in thediaphragm because of which the valve is out of calibration;then the diaphragm chamber assembly is to be, changedwith new FM Positioner diaphragm chamber assembly.(Because, only diaphragm cannot be changed.) If there isany leakage around the O-rings [21], then these can be,replaced separately.
2.2] Piston-cylinder assembly: Remove spring [10]. Removescrews [30](3 numbers), [17] and washer [33]. Lift thediaphragm chamber assembly [5] carefully so that the piston[4] is visible and comes up. Check for dust and remove it.Observe piston. If there are scratches on its surface, replaceboth the piston and cylinder.
2.3] Gaskets: Apply soap solution on the gasket [18] surface.Check for bubbles giving maximum supply. If it is leakingthen, remove, the screw [31], remove the change-over-switch [13]. Check for tear on the gasket surface, if there istear replace the gasket, if not then press it at its placeapplying some lock-tight place the change-over-switch on itssurface and tighten the screw [13] properly. It would havebeen loose earlier.Also, check all other screws, sir-clips for tightness. Check forplay between the stroke scanning lever [16] and shaft [14].
2.4] Check bearings. If jammed, replace with new.2.5] Ensure cam is rolling properly on the roller with its curve
passing smoothly over the roller surface.2.6] Check and tighten the zero-adjustment screw [20].
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USER’S MANUAL47
3] How to know the Positioner diaphragm assemblyleakage?
3.1] Diaphragm chamber assembly: Open the Positioner coveras discussed in above problem. Connect full signal of 20mafrom I/P. Spray soap solution on the diaphragm chamberassembly. *Ensure the soap solution does not enter thepiston cylinder assembly. If there is any puncture in thediaphragm because of which the valve is out of calibration;then the diaphragm chamber assembly is to be, changedwith new FM Positioner diaphragm chamber assembly.(Because, only diaphragm cannot be changed.) If there isany leakage around the O-rings [21], then these can be,replaced separately.
4] How to change the valve characteristics using the cam andswitches?
4.1] Disassemble the Positioner cover as discussed earlier. Findthe current characteristics on the plate stuck inside thePositioner housing.*Suppose the characteristics are linear and are to bechanged to equal percentage. The plate will be showing likethe figure.
4.2] Remove screws (m6x12). Remove cam. See on the label. Asper that, select the curve and side of the cam and set, suchthat the selected curve rests on the roller and reassemble.
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USER’S MANUAL48
5] How to change the direct/reverse action of Positioner?
Let us first understand what is direct action or reverse action.Direct action: Is when the O/P of the Positionerincreases, with the I/P given to it through the ‘I to P’increases.
Reverse action: is when the O/P of the Positionerdecreases, with increase in I/P to it given by I to P converteror vice-versa.
In case of Positioner, input is the signal in ma given by I to Pconverter and the O/P is the supply air.
Let us assume that the present action of Positioner is directand we want to change it to reverse. Proceed as per thesteps given bellow:
5.1] Take out the Positioner cover and remove the air supply asusual.5.2] Refer the plate inside the Positioner.5.3] Watch the Fig. No. [2] in the chart given.5.4] Remove the spring carefully.5.5] Unscrew [35]. Pullout the cam [13]. Unscrew [31]. Pullout the
change-over-switch [6]. Now the gasket [18] is exposed.Please do not remove this gasket. Suppose now the ‘N’mark, on the change-over-switch [6] is on the reference markon the Positioner housing.
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USER’S MANUAL50
5. POSITIONER PART LIST :
FORBES MARSHALL
USER’S MANUAL51
FM PNEUMATIC ACTUATOR
1. U-SERIES2. MSA SERIES
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USER’S MANUAL52
25 NAME PLATEWASHER 1024 SOCKET SCREW23 CAP22 SLIDE BEARING21 SUPPORTIING DISC
SPRING HOUSING
SPINDLEADUJUSTMENT BOLT
DESCRIPTION
SPRING PLATE
TEFLON WASHER
I.NO.
19
161718
20
87
54
6
9
21
I.NO.
3
BUSHSCREW
LIFT PLATESUPPORT
DESCRIPTION
SOCKET SCREWHEX. NUT
STAR WASHERHEX. NUT
ACTUATOR-AIR TO OPEN
FIG.
LIFT INDICATOR
HEX. BOLT 30HEX. NUT29WASHER28
30
2928
27
2625
22
27 HEX. BOLT 26 RIVET
2021
19181716
LOCK NUTDIAPHRAGM COVER
3
4
9
5
1
2
DIAPHRAGM PLATESPRING
DIAPHRAGM13
1112
1415
87
23
12
11
1314
24
15
10
6
a About The Product:
DRAWINGS OF THE PRODUCT
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USER’S MANUAL53
10 WASHER NAME PLATE25
LIFT INDICATOR
FIG.
ACTUATOR-AIR TO OPEN
HEX. NUTSTAR WASHER
HEX. NUTSOCKET SCREW
DESCRIPTIONSUPPORTLIFT PLATE
SCREWBUSH
3
I.NO.12
9
6
45
78
20
181716
19
I.NO.
TEFLON WASHER
SPRING PLATE
DESCRIPTION
ADUJUSTMENT BOLTSPINDLE
SPRING HOUSING
SUPPORTIING DISC21SLIDE BEARING22CAP23SOCKET SCREW24
6
10
15
24
1413
11
12
23
7 8
1514
1211
13 DIAPHRAGM
SPRINGDIAPHRAGM PLATE
2
1
5
9
4
3
DIAPHRAGM COVERLOCK NUT
16171819
2120
RIVET26HEX. BOLT 27
22
2526
27
2829
30
28 WASHER29 HEX. NUT30 HEX. BOLT
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USER’S MANUAL54FIG. B
6
10
16
24
1718
11
12
23
7 8
2
1
5
9
43
151413
19
2120
22
25
26
27
2829
30
HEX. BOLT 30HEX. NUT29WASHER28
27 HEX. BOLT 26 RIVETLOCK NUT
DIAPHRAGM COVER
DIAPHRAGM PLATESPRING
DIAPHRAGM13
1112
1415
ACTUATOR-AIR TO CLOSE
24 SOCKET SCREW23 CAP22 SLIDE BEARING21 SUPPORTIING DISC
SPRING HOUSING
SPINDLEADUJUSTMENT BOLT
DESCRIPTION
SPRING PLATE
TEFLON WASHER
I.NO.
19
161718
20
87
54
6
9
21
I.NO.
3
BUSHSCREW
LIFT PLATESUPPORT
DESCRIPTION
SOCKET SCREWHEX. NUT
STAR WASHERHEX. NUT
LIFT INDICATOR
25 NAME PLATEWASHER 10
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USER’S MANUAL55
101112
87
54
6
9
21
I.NO.
3
SPLIT PINDOWEL PIN
SUPPORT
HEX. BOLT
HAND WHEELCASTLE NUT
DESCRIPTION
LOCK RINGSPINDLE
BUSHTEFLON DISC
LOCKNUT
HAND WHEEL-AIR TO OPEN
FIG.
34
9
5
8
67
1
CLAMPING RING
1011
2
GRUB SCREW13
12
13
13
LOCKNUT12
HAND WHEEL-AIR TO OPENCLAMPING RING
FIG.
TEFLON DISCBUSH
SPINDLELOCK RING
DESCRIPTIONCASTLE NUTHAND WHEEL
HEX. BOLT
SUPPORT
DOWEL PINSPLIT PIN
3
I.NO.12
9
6
45
78
1110
13
13
12
13 GRUB SCREW
2
11 10
1
76
8
5
9
43
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b. Principle Of Operation:
(REF. FIG. )
The universal diaphragm actuators are operated by compressedair.The air is admitted in the diaphragm cover (28), which deflects thediaphragm (32), which in turn moves the actuator spindle (37)which compresses the springs between the diaphragm plate (38)and spring plate (33). By removing air from diaphragm cover, thespring expands which results in the movement of the spindle inopposite direction. Thus the actuator spindle actuated one way byair and other way by spring._____________________________________________________
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c. Getting Started:
General Instructions:
The name plate (39) on the actuator contains the data concerningthe valve and actuator.
When ordering spare parts always mention the application numbermarked on the nameplate.On reversing the actuator or changing the operating conditionscheck the data on the nameplate, if necessary order newnameplate with corrected data.
After replacing the spare parts make sure that the joint betweenthe diaphragm cover (28) and the spring housing (46) and o-ringare (26) tight. Also check that lift and initial spring tension arecorrectly adjusted.
Diaphragm (32) can withstand temperature from –30°c to +100°c.To increase life of diaphragm in case of high temperature, werecommend to provide a heat protection and in case oftemperature below -10°c to provide dry air.
The mounting position of actuator is vertical on top of the valve.For other mounting position please consult us.
The diaphragm cover (28) has a connection of ¼” NPT for actuatorsize U-O/U-I and of ½” NPT for sizes U-III/U-V. The air tubing,which supplies air to the actuator must have minimum 6 mm innerdiameter. (8 mm OD x 1 mm thick).
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d. Installation:
The actuator offers easy mounting of Positioner, Roboter, air filterregulator and limit switch. The spring housing (46) has two tapingsof (M8) in front. The support (55) is constructed according toNAMUR principle and provides two tapings of M8 for mountingaccessories.
The hand-wheel arrangement is a separate subassembly, whichcan be mounted at any time. On air failure, remove the hand-wheellock (6) from the lower hole of the hand-wheel (11/17) and put itinto the hole at the upper end of the hand-wheel spindle.
In case of air to close arrangement (valve opened on air failure) toopen the valve turn the hand-wheel (1) clockwise.
In case of air to open arrangement (valve closed on air failure) toopen turn the hand-wheel anti-clockwise.
Attention: Before changing to automatic service with air, turnhand-wheel (1) to uppermost position and replace hand-wheellock to lower hole of spindle.
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e. Commissioning Of U-Series Actuator:
The initial tension of spring (38) can be adjusted so that differentoperating conditions in the valve can be adapted to the availablespring ranges.The air pressure given to the actuator must be sufficient to startthe spindle movement. If the required pressure for starting thespindle movement is above or below the desired starting signal(say 0.2 bar) it can be corrected by turning the adjustment bolt (42)until the starting signal and start of spindle movement correspond.The spring tension (i.e. starting signal) can be increased by turningadjustment bolt (42) clockwise and decreased by turningadjustment bolt (42) anti-clockwise.
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f. Reversibility Of The Actuator:
The actuator is constructed in such a way that it can be reversedat any time without additional parts and thus the valve canchanged from air to open to air to close and vice versa. This canbe achieved as follows:
Unscrew screws (2 no.) and remove cap (22).
Unscrew bolts (4 no).
The diaphragm cover (28) and spring housing (4^) bolted togethercan be mounted in reverse sense (i.e. upside down) on thesupport (55).
Tighten all 4 bolts (21) and also assemble cap (22) by tightening 2screws (23).
If the diaphragm cover (28), is on top the increasing signalpressure effects a downward movement of the actuator spindle(37).
If the diaphragm cover (28) is below the top, the increasing signalpressure effects an upward movement of the actuator spindle (37).
The hand-wheel arrangement is designed for one action only. Forreversing the hand-wheel arrangement with ‘diaphragm cover’below, part no 7,8,9,10,11,15,16 & 17 are required. However forhand-wheel arrangement with ‘diaphragm cover on top’ part no4,5,11,14 & 18 are required.
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• ACTUATOR TIPS:
The actuator has enormous spring force, especially in case ofreinforced springs. It is not possible to release the spring totally byadjustment bolt (42) in every case. Therefore, use the mountingaid.
The mounting aid consists of long hex bolts and special nuts asshown in the drawing._____________________________________________________• Exchange of spares:
The mounting shows the mounting proceedings for the twoactuator-versions ‘O’ (air to open) and ‘S’ (air to close) and for thedifferent spare parts. Proceed with the mounting step by step asgiven. (refer mounting plan.)
• Mounting successions:
At first remove only 2-2 nuts and bolts (34 & 36) symmetrically asshown in the drawing.
Replace these with the mounting aids and tighten.
Now loosen and remove all nut and bolts (34 & 36).
Loosen the mounting aids slowly and evenly, so that thediaphragm cover and spring housing separate, releasing the springtension.
Now actuator can be further dismantled and spare parts can bereplaced as per mounting plan. The re-assembly follows in reversesuccession._____________________________________________________
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FIG.THE MOUNTING AIDS.
SCREW DESIGNATION
M8 x 75, ISO IN mm.
TYPE-UI
TYPE-UIII
M10 x 150, ISO IN mm.
A
75
145
B
65
133 11
9
D
17
13
SW
M10
M8
M
150
75
L
UIII & UV
UI
TYPE
NO. AND DISTRIBUTION OF
TYPE-UV
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PART LIST OF U SERIES ACTUATOR:SR.NO.
CODE PART NAME
A2007103 SPRING HOUSING UI-20/30 ACTRA2007105 DIAPHRAGM PLATE UI ACTRA2007107 DIAPHRAGM COVER UI ACTRA2007109 SPRING PLATE UI ACTUATORA2007118 SPINDLE UI-ACTUATORA2007119 DIAPHRAGM (UI) ACTRA2007120 ADJUSTMENT BOLT UI ACTUATORA2007121 BUSH UI ACTUATORA2007122 TEFLON DISC UI ACTUATORA2007123 SLIDE BEARING UI MATL. TAURUS TFE(60 PERCENT
BRONZE FILLED PTFE)A2007127 SUPPORTING DISC UI ACTUATORA2007140 NAME PLATE FOR ACTUATORA2007141 ATTENTION LABELA2007150 SPRING UI-20 STDA2007152 SPACERA2007155 SUPPORT UI-20 MACHINEDA2007156 LIFT PLATE (UI 20)A2007157 LIFT INDICATOR UI-20 ASSLY MACHINEDA2007158 LIFT INDICATOR UI MACHINEDA2026411 O RING 16 ID X 3.5 SEC.DIA.A6007139 INSERT M8 FOR UI/UIII QTY.-4A6007143 INSERT M10 UI SPRING HOUSING/4 UI DIAPHRAGM
COVER/4A6020379 ALLEN SCREW M8X35LG GR 12.9 MAKE-TVS BLUE
ZINC PLATEDA6020500 LOCK NUT M20X1.5LG GR 4A6020539 HEX NUT M 8 GR.4A6020575 STAR WASHER M20 MS ZINC PLATEDA6020582 PLAIN WASHER M20 STEEL ZN PLATED ANSI-
B18.22.1.1965.R1975A6020739 HEX NUT M8X1.25X30L ZINC PLATEDA6020997 BOLT HEX HEAD M10X25L GR 4.6A6060043 BOLT HEX M8X30 GR.4.8A6096303 HEX. NUT M4 GR.4A6096305 BOLT CH/HD M4X16L GR.4.8A6096306 PLAIN WASHER M4 ZN/PL. (ID = 4.3)A6096308 STAR WASHER M4 CHEM/BLA6096334 PLAIN WASHER M8 MS ZINK/PL
**** FOR CODES OF U-III AND U-V ACTUATOR USE A20072__ &A20074__
RESPECTIVELY IN PLACE OF A20071__
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2. MULTI SPRING ACTUATOR
a. About The Product:DRAWINGS OF THE PRODUCT
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b. Principle of Operation:
(REF. FIG.)
The Multi-Spring Actuators [MSA] are operated bycompressed air.The air is admitted in the actuator housing (11), which deflectsthe diaphragm (9), which in turn moves the actuator spindle(6) which compresses the springs between the diaphragmplate (4) and actuator plate (1). By removing air fromdiaphragm cover, the springs expand which results in themovement of the spindle in opposite direction. Thus theactuator spindle actuated one way by air and other way bysprings.
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c. Getting Started:
General Instructions:
The nameplate on the actuator contains the data concerning thevalve and actuator.
When ordering spare parts always mention the application numbermarked on the nameplate.On reversing the actuator or changing the operating conditionscheck the data on the nameplate, if necessary order newnameplate with corrected data.
After replacing the spare parts make sure that all the jointsespecially between the actuator cover (1) and the actuator housing(11) and o-ring are (28) tight. Also check that lift and initial springtension are correctly adjusted.
Diaphragm (9) can withstand temperature from –30°c to +100°c.To increase life of diaphragm in case of high temperature, werecommend to provide a heat protection and in case oftemperature below -10°c to provide dry air.
The mounting position of actuator is vertical on top of the valve.For other mounting position please consult us.
The diaphragm cover (1) has a connection of ¼” NPT for actuatorsize MSA-I and of ½” NPT for sizes MSA-II/III. The air tubing,which supplies air to the actuator must have minimum 6 mm innerdiameter. (8 mm OD x 1 mm thick.)
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d. Installation:
The actuator offers easy mounting of Positioner, Roboter, Air FilterRegulator and Limit Switch. The spring housing (11) has twotapings of (M8) in front. The support (22) is constructed accordingto NAMUR principle and provides two tapings of M8 for mountingaccessories.
The hand-wheel arrangement is a separate subassembly, whichcan be mounted at any time.
In case of air to close arrangement (valve opened on air failure) toopen the valve turn the hand-wheel (1) clockwise.
In case of air to open arrangement (valve closed on air failure) toopen turn the hand-wheel anti-clockwise.
Attention: Before changing to automatic service with air, turnhand-wheel (30) to uppermost position.
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e. Assembly Instructions For MSA Actuators:
* Actuator assembly:1] Ensure all parts are deburred, clean and lubricated.2] Assemble diaphragm plate (7), diaphragm (9),
diaphragm plate and guide assembly, sequentially, onthe spindle (3). Ensure that o-ring (8) is in position.Tighten lock-nut (10) on to the spindle.
3] Assemble the boss base (17), to diaphragm housing(11) ensuring o-rings (18) & (20) and slide bearing (38)in the place.
4] Lubricate spindle assembly; insert it from top in thediaphragm housing assembly till the end. Alignassembly bolt holes of the diaphragm with that ofdiaphragm housing.
5] Place selected type and quantity of springs (3) on thediaphragm plate (7) duly guided it the bottom as perdrawing.
6] Position spring cover (1) on diaphragm housing, alignassembly bolt holes.
7] Insert two long assembly bolts M8 x 30 diametricallyopposite and tighten nuts by one turn alternatively tillall the bolts of standard M8 x 25 size can be insertedproperly and can be nuts engaged. Replace twonumbers M8 long bolts by standard M8 x 25 bolts.Tighten all bolts partially till fully tightened up to torquelevel of 10 N-m.
8] Establish pneumatic connection at (11) the base ofactuator housing. Pressurize assembly and check forease of spindle movement, lift (should be at least 2 mmmore than specified) and leakage from joints (raisesupply pressure to 5 bar).
9] Assemble nut cover along and cap plastic at respectiveplaces.
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* Actuator and Support Assembly:1] Place the actuator on the top of actuator support,
locate plug in the hole provided on top of face of thesupport. Tighten nut-spindle on boss base ensuring itslocation in the step provided in the support. Thisensures alignment of valve and actuator spindle.
2] Tighten nut-spindle fully using C-spanner.
* FM vale and Actuator assembly:1] For Air to Open operation, ensure that the valve
spindle is completely down and plug is sitting tight onthe seat.
2] Place actuator-support on the valve top flange takingguidance of the step on valve top flange. This ensuresalignment of valve and actuator spindle.
3] Clamp two halves of the lift indicator, carefully aligningthe split threads of the indicator with that of spindle.
f. Reversibility Of MSA Actuator:
The actuator is designed in such away that it can bereversed at any time without additional parts and thus valvecan be changed from Air to Open to air to Close and reverse.This can be done in following sequence:a. Remove nut cover (15)/hand-wheel assembly from
actuator cover (11).b. Remove lock nut (14) from top of spindle (6).c. Remove spindle off the actuator assembly from bottom
side.d. Remove boss base from actuator housing.e. Insert spindle from top of the actuator aligning in the
guide-diaphragm plate (5). Tighten lock nut on thespindle.
f. Assemble boss-base, along-with o-rings and slidebearing on actuator cover.
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Tightening Torque Moments:
THREAD SIZE TORQUE MOMENTN-m
M8 10M10 16M12 30M16 70M20 100
Spring Location (on the spring plate over the boss):*Initially take any boss as no. 1 and count from that.
NUMBER OF SPRINGS LOCATION2 1.43 1,3,54 2,3,5,66 1 to 6
>6 1 to 6 and in abovesequence
g. PART LIST OF MSA ACTUATOR: Refer Fig. On Pg 64
SR NO. CODE PART NAME
A2007119 DIAPHRAGMA2007156 LIFT PLATEA2007158 LIFT INDICATORA2007223 SLIDE BEARINGA2026419 O RING 20 I.D. X 3.5 C/SA2026421 O RING I.D.13 X 2.5 C/SA2098001 SPRING COVERA2098002 O RING 26 I.D. X 5 C/S NITRILE RUBBERA2098004 SPRING WASHER M8A2098005 LOCK NUT M12A2098013 NUT-SUPPORT M/CED MSA1A2098016 DIAPHRAGM PLATE M/CED MSA1A2098017 GUIDE –DIAPHRAGM PLATE SS410A2098018 SPINDLE M/CED SS410 MSA1A2098020 SUPPORT-DIAPHRAGM PLATE SS410A2098022 BRACKET AFR MOUNTING MSA
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A2098025 DIAPHRAGM HOUSING M/CED MSA1 MAT LSA2098026 PLUG VENT 1/4 NPT MS ELECTROPLATEDA2098027 PLUG BLIND 1/4 NPT MS ELECTROPLATEDA2098028 BOSS BASE SS410 MSA1 MACHINED.A2098029 SUPPORT ACTUATOR MSA1 (UI 20)
MACHINEDA20980356/7/8/9 SPRING TYPE A/B/C/D/E
A2098041 PLATE PRODUCT C.V. --- ---A2098042 PLATE ATTENTION --- ---A6020539 HEX NUT M 8 GR.4A6060045 HEX BOLT M8 X 25L GR. 4.8A6060046 HEX. BOLT M8X35L GR. 4.8A2007122 TEFLON DISCA2007127 SUPPORTING DISCA2007176 HANDWHEELA2007180 PIN LOCK HANDWHEEL (R-TYPE)A2098006 HANDWHEEL SUPPORT SS410 AIR TO OPENA2098007 HANDWHEEL SPINDLE SS410 AIR TO OPENA6020516 HEX LOCK NUT M20 GR.4 ZINC PLA6020929 GRUB SCREW M6X20L
3. TROUBLE SHOOTING
1] How to reverse actuator with or without hand-wheel?
1.1] Open the valve till its 10% opening giving signal ofaround 6 mA or manually using hand-wheel.
1.2] Unscrew the coupling. Disassemble the lift indicatorand remove the hand-wheel assembly by unscrewingthe grub screw (35), hand-wheel support (36) andhand-wheel assembly (30) in anti-clockwise direction.
1.3] Remove all the tubing. Remove Positioner andaccessories if any.
1.4] Unscrew the spindle nut (21); remove any two appositenut bolts of the actuator and insert two no. Long bolts
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[M8] size. This is for avoiding accident that mighthappen due to initial compression of springs.
1.5] Unscrew all the remaining nut-bolts diagonally.1.6] Remove the cover (1), springs (3).1.7] Pull out the diaphragm plate assembly with the spindle
(6).1.8] Hold the spindle in vice in the slots at its bottom.
Unscrew lock nut (10), remove diaphragm plate (4),diaphragm (9), o-ring (8),‘Diaphragm plate support’ (7).
1.9] Assemble all above parts from diaphragm plate support(1), as shown in the ‘air to close diagram.
** It is essential to order boss base (17), with two o-rings(20) and slide bearing (19) and air to close hand-wheelassembly as shown or if the actuator is without hand-wheel then nut cover (2).
1.10] Assemble the diaphragm plate assembly into the cover(1) as shown in figure air to close.
1.11] Tighten the spindle nut (21).1.12] Do all the tubing to the actuator housing (11) in the
vent provided (27).
** a) There are certain changes to be made inPositioner/Roboter as the case may be. these areexplained in the respective manuals.
2] How to check diaphragm failure and air leakage?
2.1] Give 6 Bar air supply at air inlet (27).
2.2] Put soap solution near ‘boss base assembly’ (17). Allthe joints,
Spindle and cover interface and diaphragm clutching(periphery) and check for bubble. No leakage isallowed. In case of leakage tighten the joints or changethe o-rings with respect to the area of leakage.
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3] How to change and increase/decrease forcecapability?
3.1] Force capabilities can be changed, by increasingnumber or type of springs. This is for MSA-I actuator.In case of U-series, turn the adjustment bolt clock-wisetill the desired lift position of valve spindle is achievedat higher air pressure. In case further force capabilitiesare required, change the spring type to re-enforce fromstandard and if already re-enforced is used then go forhigher sized actuator.
4] How to adjust (using coupling) the valve lift with theactuator lift?
4.1] Change the position of end of valve spindle in thecoupling and adjust its distance with the actuatorspindle such that the valve completes its travel.
5] How to check the spring range?
5.1] Give air pressure to the actuator slowly.5.2] Note the pressure reading when the actuator spindle
starts moving. Suppose the spring range is 0.2 to 1.0bar. The actuator spindle starts moving at 0.2 bar andattends maximum lift at 1 bar. If any deviation in this isfound then couple the actuator spindle with the valvespindle at the required lift.
6] How to mount various accessories on theactuator?
6.1] Mounting the Positioner:Mount the Positioner on, the support on inlet side of thevalve at opposite side of air inlet of the actuator. Fit thePositioner link on lift indicator. Fit the Positionermounting bracket to the Positioner. Fit the threaded pinin to stroke scanning lever depending upon valve size.Fit the Positioner support/yoke.
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Mounting Position Transmitter:
Fit the Positioner link of Positioner link on the opposite sideof Positioner. Mount the bracket to Position Transmitter. Fitthe stroke-scanning lever to shaft, which is extruding out ofthe Transmitter. Fit the threaded pin to stroke scanning leverdepending upon size of valve. Mount the PositionTransmitter, on support on opposite to Positioner on theother leg of support.
AFR/ALR/Booster Relay/I to P/ Solenoid Valve:Mount the bracket on actuator by loosening any of theactuator cover bolt nearest to the Positioner and accessoriesto be connected to it to save tubing length. Fit the AFR/ALRon the bracket.
Limit Switches:Mount the limit switches on its bracket using screws/nuts.Mount the bracket on the hand-wheel support using M8x20mm size bolt.After mounting proper tubing as per plan is to be made.Ensure Zero Leakage.
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FM VALVE MOUNTEDPRESSURE CONTROLLER
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1. ABOUT THE PRODUCT:
a General Description:
This Valve Mounted pressure controller is a yet solid one for directmounting to the control valve and direct impulse connection forvarious pressures including vacuum and absolute pressures.
It has the following outstanding characteristics:
1. Separate interchangeable measuring units.2. In-built supply air restrictor and output damping
throttle.3. Reversal of action without additional parts.
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b Specifications:
Measuring Range : 0.02 To 400 Bar
Absolute Pressure : 0.05 To 3 Bar
Vacuum : 0-1 Bar Low Pressure
Supply Air Pressure : 1.4 Bar
Control Pressure : 0.2-1 Bar
Set Point/Actual Value : See Fig. No. B
Speed Of Response Range : <0.02% Of Medium Set Point
Reversal Range : <0.033% Of Medium. SetPoint
Hysterisis Range : <1.1% Of Medium Set Point
Dependence On Supply Pressure : <0.4% Per 0.1 Bar
Air Consumption : 300 NL/hrOn Y=0.6, Z=1.4,Nozzle=Dia. 0.2
Valve Speed : 40 Sec. Up/ 5 Sec DownNozzle 2, Actuator UI-30140 Sec Up/20 Sec DownNozzle 2, Actuator UIII-60.
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c Operation:
Ref. Fig.
The pressure to be controlled, ‘x’, which is acting on themeasuring unit (bellows, diaphragm, etc.) is compared to aset point spring, ‘w’. Any deviation in ‘x’ alters the valvediaphragm pressure ‘y’ at the nozzle, altering the flow tothe actuator and thereby the lift. This alteration in lift is fedback to the controller via the adjustable spring ‘R’.
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2. GETTING STARTED:
a. Installation:
The pressure control valve should be stored in itsoriginal packing until it is mounted. The storagearea must be dry and clean. After mounting thevalve should be supplied with control air, this isbest protection against fouling and corrosion.
The protection caps of the valve openings, of thefilter and regulating valve and of the pressurecontroller have to be taken off. If there areconservatives in the spindle area of the valve,they have to be removed carefully.
The diaphragm control valve is mounted verticallystanding up with actuator on top. The mountingplace has to be easily accessible. Maximumallowable temperature is 80 degrees centigrade.
The impulse connection is taken at about 1-2 mafter the control valve. The point of pressuretaking has to be provided with a stop valve, sothat in case of troubles you can get the measuringsystem free of pressure. Pressure tapping from avertical line where the point of tapping is abovethe measuring chamber is ideal. In this case themeasuring line can remain filled, and thepossibility of air inclusion cam be eliminated. Withviscous media the tapping point has to beprovided with a separating vessel as to avoiddelays in pressure transmission.
The separating vessel should be mounted asnear as possible to the tapping point.
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b. Mounting Instruction For PressureController
Before connecting the air supply to the air filterand regulator, the newly laid airline should becarefully blown out to line and it should beexamined for any possible leakages.
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c. Pressure Controller Part List :
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d. Commissioning The Product:
Ref. Fig. G:On start up the required air-supply is adjusted, at the AFR. Thesupply pressure should be about 0.5 bar higher than the maximumoperating pressure of the connected control actuator. (Seenameplate: CONTROL RANGE). The air is checked for moisture,dirt, etc. by operating the drain valve.The set-point spring (30) is relieved (-) by turning the nut anti-clockwise direction. The operating pressure Y now increases up tomaximum value and control valve closes. The Control Valve can,now be started as follows.Open the impulse valve slowly de-aerating the measuringchamber.Tighten slowly the Set-point spring (+) until the valve begins toopen. Set the spring tension to the desired set pressure.If controller oscillates, the measuring chamber must be de-aeratedagain. If this does not improve the situation, the proportional rangehas to be enlarged by feedback-spring (21).If the controller remains unsteady, screwing in the damping throttlecan damp the control pressure Y to the Diaphragm chamber. (16)After start up the following service has to be done. Examine ifhand-wheel is in end position and secured by lock pin. Slightlytighten stuffing box nut to avoid leakage of media. Tighten all nutson valve.
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3. OPERATION AND MAINTENANCE:
a. Basic Functions:PRESSURE REDUCING CONTROLLER:
The FM valve pressure reducing controller works as a pressure-reducing valve. If the set pressure value is surpassed, the controlvalve closes and reduces the pressure. Air is supplied at pressureZ which is to be free from dust, oil and water of at-least 4 Bar. Thesupply pr. to Roboter. Z1 is adjusted on the Air Filter Regulator (1).The supply air reaches the nozzle flapper system through theconstant restrictor (18). The flapper (25) at the nozzle lever (26)covers the nozzle (9) more or less depending upon the pressuredeviation at the bellows (35). This in turn changes the controlpressure y supplied to the actuator. The air supply is limited to afixed value by the fixed throttle (18) so that with open nozzle, thepressure goes towards zero and the actuator can assume the fail-safe position as determined by the spring. (In the given fig.Actuator is mounted in air to close position) At the outer end of thelever (26), an adjustable feedback spring (21) is connected. Byblocking some spring threads, the feedback force can be changeddepending on the lift position of the control valve. If the feedbackspring is tightened, the proportional range is widened and thecontrol loop is attenuated. If the feedback spring is loosened, theproportional range is shortened and the control loop reacts moresensitively and may even tend to vibrate. The output signal y canbe dampened by a damping throttle (16). The set-point spring (30)secures the lever (26) in its bearing and counteracts the force onthe impulse pressure, X, at the measuring system. The bellowsassembly consists of the below (35) and the thrust bolt (29).Depending on the impulse pressure X at the bellow (35), thedistance between nozzle and flapper is changed and thereby thecontrol pressure Y.
Referring to Fig H, when impulse pressure increases the levermoves upwards, nozzle closes, control pressure increases andvalve closes. On decreasing impulse pressure X, the lever movesdown, nozzle opens, control pressure decreases and valve opens.The set value of the spring W can be adjusted by a nut (33) bytightening & releasing the spring tension (30) .On the cover thistightening or loosening is marked as "+" or "-" respectively. If set-
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point spring is tightened (+) control pressure Y decreases, setvalue W increases. If set point spring is loosened (-), controlpressure increases, set value W decreases. The air supply islimited to a fixed value by the constant fixed throttle (18) so that; itopens nozzle the pressure goes towards zero and the actuator canassume the fail-safe position as determined by the spring. (In thegiven fig. The Actuator is mounted in air to close position). At theouter end of the lever (26) an adjustable feedback spring (21) isconnected. By blocking some spring threads, the feedback forcecan be changed depending on the lift position of the control valve.If the feedback spring is tightened, the proportional range iswidened and the control loopIs attenuated. If the feedback spring is loosened, the proportionalrange is shortened and the control loop reacts more sensitivelyand may even tend to vibrate. The output signal V can bedampened by a damping throttle. (16).2.2 The set-point spring (30) secures the lever (26) in its bearingand counteracts the force on the impulse pressure, X, at themeasuring system. The bellow assembly consists of the bellow(35) and the thrust bolt (29). Depending on the impulse pressure Xat the bellow (35), the distance between nozzle and flapper ischanged and thereby the control pressure V.
Referring to Fig. No. 1, when impulse pressure increases the leverupward, nozzle opens, control pressure decreases and valveopens.
The set value of the spring W can be adjusted by a nut (33) bytightening or releasing the spring tension (3.0) On the cover thistightening & loosening is marked as "+" respectively. If set-pointspring is tightened (+) control pressure y decreases, set value Wincreases. lf set-point spring is loosened(-), control pressure increases, set value W decreases.
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4. TROUBLE SHOOTING:
In case there is trouble in starting, the valve can be operated inany position by means of the hand-wheel It is to be noted that aftermanual operation, the hand-wheel should always be set back intoend position and locked by means of a lock pin. In case of Viscousmedia the application of a separating vessel is necessary, theinstallation should be arranged as showing Fig numbers' (a) & (b).The lines have to be, arranged with a slope of 1: 10 so that theenclosed air bubbles can go up to the de-aeration points. Beforestart-up the impulse lines, controller and separating vessel shouldbe carefully filled with a separating, liquid (e.g. Barium Chloride orGlycerin) .It has to be observed that the least possible air entersinto the system. Then the valve is to be carefully opened. Themedia exerts pressure on the separating liquid in the separatingvessel and the system is once more de-aerated. This is veryimportant as the air bubbles rise in the measuring system andcause oscillation.
Q1] How to change springs and bellows?
Remove the cover [6] by unscrewing the M5x10L screws[2](4 noose).
Unscrew the hex-nut [33]. Take-out the bearing [32].
Take-out the spring [30] and spring-plate attached to it[28]. Turn the notches using Plyer; ensure that thenotches are not damaged. Now take out the spring andreplace with new.
For bellow: 3.5] remove the cover [6] by unscrewing theM5x10L screws [2](4 nos.).Unscrew the Allen-bolt (M8x35) [20] 4nos. Remove thebellow chamber assembly [37].Replace bellow with new one.Fix the new bellow by tightening Allen-bolt(M8x35) [20].
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Q2] How to adjust Roboter settings for given valvelift?
Check what is the set pressure of valve – check theaction of Roboter. Suppose the valve is 80#150.Observe on the VDS. The set pressure and the action ofRoboter are given on it. Suppose the action is reverseacting down stream control and set pressure is 4.5 bar.Also check spring and bellow size as per the VDS.
Remove the cover [6] by unscrewing the M5x10Lscrews [2](4 nos.). Take out the ball bearing [32], hex nut[31], set point spring [30].Polish the flapper [25] with smooth polish paper andneedle file and hit the contact screw [29] by soft headedmallet/hammer to make the nozzle [9] impression onflapper [25]. Check for impression. If not there, on theflapper r then repeat above steps.Give air supply to AFR. Adjust the pressure of the airbetween (3-3.5 bar). Rotate the hex nut [31] in clockwisedirection so that the valve opens fully [i.e. 30 mm forgiven valve. Check the pipeline for air leakage byspraying soap solution near all the joints. There must notbe any leakage. Rotate the hex nut [31] in anti-clockwisedirection until the valve is 50% open i.e. 15mm. Checkthe double arm lever [ ] to be horizontal. If not then byrotating the adjustment lever [ ] make the double armlever horizontal. Rotate the contact screw [29] making ittouch the bellow [44]. Again, rotate it 1 ½ [1.5 mm]rotation of contact screw. Now the valve should becompletely close. [If not the Roboter is to be replacedcompletely.] Apply set pressure 4.5 bar through siphon. Ifsiphon is not used then bellow might get burst. To checkthe bellow chamber is completely filled observe theflowing medium coming out at the air vent port. Now tightthe air vent screw [39].Rotate the hex nut [33] up to 50 % opening of the valve.Increase the set pressure 4.5 bar till the valve is fullyclosed. Ensure output pressure [p1] on the gauge [13] to
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be zero or less than operating control range of valve.Note that pressure. Then decrease the pressure [p2]bellow 4.5 bar. Do it until the valve gets open fully. Applyset pressure 4.5 bar and ensure the valve is 50% open.
To check smooth operation of the valve we should checkthe proportionate band. {= (P1-p2)/(set pr. X 100)} thisformula should give result between 10 % to 40 %.
Q3] How to change the nozzle?
Remove the cover [6] by unscrewing the M5x10L screws[2](4 nos.).Unscrew the hex-nut [33].Take-out the bearing [32].Take-out the spring [30] and spring-plateattached to it [28].
Remove the flapper lever [26]. Unscrew the (m4x40)screw 2nos. [7]. Take out the traverse [12] and traversehead assembly [8]. Unscrew the nozzle [9] and replacewith news.Assemble in reverse as above steps.Recalibrate.