Edition: 2023-04

Mi-205 EN
Operation and service instruction
Butterfly valves
Type MTV/FSV

Type MTV/FSVW Wafer design

Type MTVF/FSVF Flanged design
Type MTVL/FSVL Lugged design
Type FSVG Wafer design with guiding lugs

Nominal pressure PN 10 - 25, Class 150

Nominal Size DN 80 - 500 NPS 3 - 20 MTV / MTVF
DN 100 - 500 NPS 4 - 20 FSVW / FSVF / FSVL /FSVG
DN 80 - 350 NPS 3 - 14 MTVL
 Edition: 2021-09 Original document - Mi-205 EN

Introduction
This operating manual is intended for the operating, maintenance and
supervisory personnel.

This operating manual also describes components, equipment and ancillary units
which are not or only partially included in the scope of supply.

The operating personnel must have read, understood and must comply with this
operating manual.

We keep the right to do any technical changes which are necessary to improve the
product without prior notice.

Copyright
Copyright by Somas Instrument AB. No part of this publication may be
reproduced, stored in a retrieval system, or transmitted in any form or by any
means, graphic, electronic, mechanical, photocopying, recording, taping, or
otherwise without the prior permission of the copyright owner.

Supplier
Somas Instrument AB
Norrlandsvägen 26-28
SE-661 40 SÄFFLE
SWEDEN

Phone: +46 (0)533 69 17 00

E-mail: sales@somas.se
Website: www.somas.se

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Contents
1 Introductory information 6

1.1 Explanation of warnings, symbols and signs 6

1.1.1 Warnings 6
1.1.2 Symbols and signs 7

2 Safety 8

2.1 Safety instructions 8

2.1.1 General dangers 8

2.1.2 Hazards due to electrical equipment 8
2.1.3 Additional hazards 8
2.1.4 State of the art 9
2.1.5 Preconditions for using the valve 9

2.2 Designated use of the valve 10

2.2.1 Use 10
2.2.2 Liability for non-designated use 10

2.3 Organizational measures 11

2.3.1 Availability of operating manual 11

2.3.2 Additional regulations 11
2.3.3 Checks 11
2.3.4 Protective equipment 11
2.3.5 Rebuilds or modifications at the valve 11
2.3.6 Replacing damaged parts 11

2.4 Selection and qualification of personnel 11

2.5 Safety instructions for butterfly valves 12

3 Description 15

3.1 General information 15

3.2 Function of the valve 15

3.3 Decommissioning and disposal 16

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4 Technical specifications 17

4.1 Specifications 17

4.1.1 Gaskets 17

4.2 Fastening torque for flanges 19

4.2.1 Fastening torque for flanges valve body 19

4.2.2 Fastening torque for stuffing box 20
4.2.3 Tightening torque for screws in valves 21

5 Assembly 22

5.1 Unpacking and transportation 22

5.2 Installation of the valve in the pipeline 23

5.2.1 Important information for installation 24

5.2.2 End of line installations 24

5.3 Start up 26

5.4 Disassembly of the pneumatic actuator 27

5.5 Positioning of the shaft with disassembled actuator 28

5.6 Assembly of the pneumatic actuator 29

5.6.1 Actuator mounting alternatives 31

6 Maintenance 32

6.1 Disassembly of the butterfly valve from pipeline 32

6.2 Maintenance 33

6.2.1 Procedure to evaluate a leakage on a butterfly valve with pneumatic 34

actuator installed in a pipeline
6.2.2 Procedure to evaluate a leakage on a butterfly valve with gear 36
installed in a pipeline

6.3 Installation and disassembly of the stuffing box 38

6.4 Replacing the seat (standard metal seat) 40

6.4.1 Disassembly 41

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6.4.2 Cleaning, lubrication and assembly 41

6.5 Replacing the PTFE seat 42

6.5.1 Disassembly 43
6.5.2 Cleaning, lubrication and assembly 43

6.6 Replacing the Fire safe seat 44

6.6.1 Disassembly 45
6.6.2 Cleaning, lubrication and assembly 45

6.7 Adjustment of the end position on pneumatic actuator 46

6.7.1 Setting of the ”closed” position on the butterfly valve 47

6.7.2 Setting of the ”open” position on the butterfly valve 47

6.8 Adjustment of the end position on gear 48

6.8.1 Setting of the ”closed” position on the butterfly valve 49

6.8.2 Setting of the ”open” position on the butterfly valve 49

6.9 Leak test of the valve 50

6.10 Components 52

6.10.1 MTV DN 80-150, with metal seat 52

6.10.2 MTV DN 200-300, with metal seat 53
6.10.3 MTV DN 350-500, with metal seat 54
6.10.4 MTV DN 80-150, with PTFE seat 55
6.10.5 MTV DN 200-300, with PTFE seat 56
6.10.6 MTV DN 350-500, with PTFE seat 57
6.10.7 FSV DN 100-150, with Fire safe seat 58
6.10.8 FSV DN 200-500, with Fire safe seat 59

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 Edition: 2021-09 Original document - Mi-205 EN

1 Introductory information
To enable you to find information quickly and reliably in the operation manual,
this chapter familiarises you with the structure of the operating manual.

This manual uses symbols and special characters which make it easier for you to
find information. Please read the explanations of the symbols given in the section
below.

Ensure that you read all the safety instructions in this operating manual very
carefully.

You will find safety instructions in section 2, in the foreword to the sections and
before any working instructions.

1.1 Explanation of warnings, symbols and signs

1.1.1 Warnings

Warnings are used in this operating manual to warn against injury and material
damage. Always read and observe these warnings! Warnings are identified by the
following symbols:

In this manual are used diverse types of safety and warning notices:

Danger!
Type of danger.
International
Advise for imminent danger. Not attention of the advices could be mortal or cause severe
Safety symbol
injuries as a consequence.
Explanation of the countermeasures.

Warning!
Type of danger.
International
Advise for imminent danger. Not attention of the advices could cause severe injuries or property
Safety symbol
damage as a consequence.
Explanation of the countermeasures.

Attention!
Type of danger.
International
Advise for possible danger. Not attention of the advices could cause property damage as a
Safety symbol
consequence.
Explanation of the countermeasures.

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i
Note
Advices and give tips for better understanding of the manual or a better handling of the valve.

1.1.2 Symbols and signs

Symbols and signs are used in this operating manual to provide fast access to
information.

1.1.2.1 Symbols and signs in the text

Symbol Denotation Explanation

Operating instructions This means there is an action to be carried out.

1. Operating instructions, Work instructions must be carried out in the

2. multi-step sequence shown.
Deviations from the sequence shown may result in
damages to the valve and accidents.

• Lists, two-stage No activities are linked with lists.

–

➔ Cross-reference References to images, tables, other sections or other

instructions.

Tab.1-1 Symbols in the text

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2 Safety

2.1 Safety instructions

2.1.1 General dangers

Sources of danger resulting in general hazards:

• Mechanical hazards

• Electrical hazards

2.1.2 Hazards due to electrical equipment

Due to the permanent dampness, electrically-operated machine parts

represent a potential source of danger.

Comply with all regulations on electrical equipment in damp areas!

2.1.3 Additional hazards

2.1.3.1 Entanglement, crushing and cut/sever hazards

• by moving machine parts left exposed, by removing covers for inspection,

sampling, etc.

• by automatic operated valves

2.1.3.2 Burning or scalding hazards

• by opening or leaving open function-check and/or sampling openings

on systems operating at high temperatures (above 40°C)

• by operating temperature >= 70°C. Short contacts (approx. 1s) of the skin
with the surface of the valve may cause burns (pr EN 563)

• by operating temperature = 65°C. Longer contacts (approx. 3s) of the skin

with the surface of the valve may cause burns (pr EN 563)

• by operating temperature 55°C…65°C. Longer contacts (approx. 3-10s)

of the skin with the surface of the valve may cause burns (pr EN 563)

2.1.3.3 Explosion hazards

A high surface temperature on a valve and actuator, constitutes (a risk for burn
injuries, and) a risk of ignition of explosive atmospheres in ATEX applications.

The surface temperature of the equipment is not dependent on the equipment

itself, but on the ambient conditions and the process conditions. The protection
from the surface temperature is the responsibility of the end user, and must be
effectuated before the equipment is put into service.

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2.1.4 State of the art

This product has been built by Somas Instrument AB in accordance with state-
of-the-art standards and the recognized safety rules. Nevertheless, its use may
constitute a risk to life and limb of the user or of third parties, or cause damage
to the valve and to other material property, if:

• the product is not used as designated

• the product is operated or repaired by untrained personnel

• the product is modified or converted improperly and/or

• the safety instructions are not observed

Therefore, every person involved in erecting, operating, inspecting, maintaining,

servicing and repairing the valve must read, understand and observe the complete
operating instructions, particularly the safety instructions.

2.1.5 Preconditions for using the valve

The valve only has to be used:

• in perfect technical condition

• as designated

• according to the instructions in the operating manual, and only by safety-

conscious persons who are fully aware of the risks involved in operating the
valve

• if all protective devices are installed and operative

Rectify immediately any functional disorders, especially those affecting the safety
of the valve!

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2.2 Designated use of the valve

2.2.1 Use

The valves are appropriate to be used in pulp and paper industry, chemical
industry, shipbuilding industry, energy industry and offshore industry.

Particular data to the operation and limit values are specified on the data sheet
“Si-205EN (MTV) and Si-202EN (FSV)”.

The operating values, limit values and setting data must not deviate from the
values specified in the operating manual and correspondig information sheet
without consulting the manufacturer! The manufacturer cannot be held liable
for any damages resulting from non-observance of the operating manual.

The user is responsible for knowing the impact from the media on the valve,
the resulting wear rate, and establishing maintenance interval, to maintain safe
operation.

2.2.2 Liability for non-designated use

Using the valve for other purposes than those mentioned previously is considered
contrary to its designated use. For resulting damages of this, Somas Instrument
AB is not liable! The user take the risk.

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2.3 Organizational measures

2.3.1 Availability of operating manual

The operating manual has to be stored and be readily available!

2.3.2 Additional regulations

In addition to the operating manual, it have to be observed all other generally

applicable legal and other mandatory regulations relevant to accident prevention
and environmental protection! Direct the personnel to comply with them!

2.3.3 Checks

Periodically check that the personnel carry out the work in compliance with
the operating manual and that they pay attention to risks and safety factors.

2.3.4 Protective equipment

Use when necessary protective equipment.

2.3.5 Rebuilds or modifications at the valve

Do not make any rebuilds or modifications at the valve yourself, which can affect
the security of the valve.

2.3.6 Replacing damaged parts

Valve parts that are not in perfect condition must be replaced immediately
with original spare parts! Use only original spare and wear parts from
Somas Instrument AB.

On unauthorized parts is not guarantee that they have been designed and
manufactured according to the application.

2.4 Selection and qualification of personnel

Operation, maintenance and repairing works require special knowledge and
may only be carried out by trained technical specialists or qualified personnel
authorized by the user.

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2.5 Safety instructions for butterfly valves

Operation of the butterfly valve is always subject to the local safety and accident
prevention regulations.

Danger!
Risk of injury!
Observe movements of the disc.
Keep hands, tools and other objects away from the area where the disc moves when the
actuator is connected to compressed air system. Single action actuators may move to “open”
or “closed” position without being connected to the air system.

Warning!
Before carrying out maintenance or repair work on the butterfly valve with actuator or
installation and removal of the butterfly valve from the pipeline, always disconnect the
compressed air supply to the actuator.
Single action actuators may move to “open” or “closed” position without being connected
to the air system.

Warning!
Ensure that personnel who work with, install or repair the butterfly valve are appropriately
trained. This prevents unnecessary damage and accidents or injury to personnel.

The maintenace and assembly personnel must be familiar with the process of installing and
disassembling the butterfly valve in a process line, the special and possible risks of the process
and the most important safety regulations.

The repair and assembly personnel must be familiar with the risks when handling pressurised
equipment, hot and cold surfaces, dangerous substances and substances which represent
a hazard to health.

Warning!
Do not exceed the design data of the butterfly valve!
Exceeding the design data marked on the butterfly valve may lead to damage and uncontrolled
escape of the pressurised medium.
Both the damage as such and the pressurised medium may lead to injuries to personnel.

Warning!
Do not remove the butterfly valve from the line as long as it is pressurised!
Dismantling or disassembly of a pressurised butterfly valve leads to an uncontrolled loss of
pressure. Always isolate the relevant butterfly valve in the pipe system; despressurise the
butterfly valve and remove the medium before working on the butterfly valve.

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Warning!
Before assembling or disassembling the pneumatic actuator of a butterfly valve installed in the
pipeline depressurise the relevant valve in the pipeline system, isolate the valve and remove the
medium before working on the valve.
The pressurised medium may lead to injuries to personnel.

Warning!
Inform yourself of the properties of the medium. Protect yourself and your environment from
hazardous or poisonous substances.
Observe the safety instructions in the safety data sheets of the manufacturers. Ensure that no
medium can enter the pipeline during maintenance work.

Warning!
Before replacing the stuffing box of a butterfly valve installed in the pipeline depressurise the
relevant valve in the pipeline system, isolate the valve and remove the medium before working
on the valve.
The pressurised medium may lead to injuries to personnel.

Danger!
Risk of injury!
Observe movements of the valve disc.
Keep hands, tools and other objects away from the area where the valve disc moves. The valve
with valve disc mounted may work as a cutting tool. Do not leave any foreign objects in the
valve body. The valve disc of the butterfly valve always works as a separate device. There is no
difference whether an actuator is installed or not. The position of the disc may change during
transport or handling of the butterfly valve.

Warning!
Protect yourself against noise - use the relevant safety equipment.
The butterfly valve may cause noise in the pipeline. The noise level depends on the type of
application and can be determined with the Somas software SomSize.
Additional noise sources in the vicinity of the butterfly valve may increase the noise level.

Warning!
Beware of very cold or hot surfaces!
The body of the butterfly valve may become very cold or very hot during operation. Protect
yourself against frostbite and burns.

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Warning!
When transporting and handling the butterfly valve, observe its weight.
Never lift the valve by its positioner, limit switch, solenoid valve or piping. Place the hoisting
ropes securely according to lift instruction.
The butterfly valve or parts thereof may injure persons if dropped.
Do not walk under suspended loads.

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3 Description
3.1 General information
The Somas butterfly valve is used for control shut-off and hand operation. The
valve is suitable for liquids, vapours and gases in a wide temperature range.

Due to the sophisticated triple-eccentric design and the special shape of the disc
a solid stainless steel seat can be used. This combination gives a solution resistant
against high flow velocity and guarantees no leakage even under severe conditions.

The seat is available in different stainless qualities and is replaceable.

The butterfly valve is designed as a wafer style valve. As alternative there is a lug
type version available.

The butterfly valve is checked and ready for use at delivery and can be equipped
with actuators, valve positioners as well as with other accessories.

3.2 Function of the valve

Fig.3-1 MTV Fig.3-2 FSV

The Somas MTV valve is equipped with a metalic seat. The Somas FSV valve is equipped with a Fire safe seat.
The tightness on the main flow direction is according to: The tightness on the main flow direction is according to:

MTV FSV
Metal seat Code D Fire safe Code F
Control valve: EN60534-4 V Shut-off valve: EN12266-1 Rate D Control valve: EN60534-4 V Control valve: EN60534-4 VI
(optional)
PTFE seat Code A
Shut-off valve: EN12266-1 Rate B
Control valve: EN60534-4 V Shut-off valve: EN12266-1 Rate C
(optional)
Control valve: EN60534-4 VI Shut-off valve: EN12266-1 Rate B
Shut-off valve: EN12266-1 Rate C
(optional) (optional)
(optional)

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i
Note
Use gaskets with the nominal size of the valve, to have a leak-proof sealing in both flow
directions.

The valve is adjustable. This means, the more the valve is closed the tighter it
becomes (➔ Fig.3-1).

Through the sophisticated triple eccentric design, the seat is relased from the disc
when opening the valve. This reduce wearing and extend the durability of the
valve.

To close the butterfly valves for liquids need less torque than valves for vapors
and gases.

The butterfly valve is tight in both flow directions. The preferred flow direction
is the direction towards the flat side of the disc. This direction is marked with
arrows on both sides of the valve.

3.3 Decommissioning and disposal

Somas valves are designed for easy maintenance and repair, ensuring an
environmentally friendly and cost-efficient use.

Replaced components and valves shall be disassembled and recycled according to

local rules and regulations.

The materials of the valve components can be found on the valve marking plate
and in Somas valve data sheets. Material information can also be acquired from
Somas Instrument AB.

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4 Technical specifications

4.1 Specifications

4.1.1 Gaskets

i
Note
To ensure pressure on the cover plate use only gaskets with right inside diameter.

For installation between pipe flanges acc. to PN 10-25, the inside diameter acc. to
EN 1514-1 of the gasket should not be exceeded, see (➔ Tab.4-1).
DN Max. inside dia. Outside dia. (dy) (mm)
(di) (mm)
PN 10 PN 16 PN 25
80* 89 142 142 142
100 115 162 162 168
125 141 192 192 194
150 169 218 218 224
200 220 273 273 284
250 273 328 329 340
300 324 378 384 400
350 356 438 444 457
400 407 489 495 514
500 508 594 617 624
* DN80 only for MTV
Tab.4-1 Gaskets diameter acc. to EN 1514-1

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To fit between pipe flanges acc. to Class 150, the dimensions acc. to
ASME B16.21 RF are valid, whereas the following dimensions for gaskets are valid
(➔ Tab.4-2).

DN Max. inside dia. Outside dia. (dy) (mm)

(di) (mm) Class 150
80* 89 136
100 114 174
125 141 196
150 168 222
200 219 279
250 273 340
300 324 410
350 356 451
400 406 515
500 508 606
* DN80 only for MTV
Tab.4-2 Gaskets diameter acc. to ASME Norm

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4.2 Fastening torque for bolts

4.2.1 Fastening torque for flanges valve body

DN PN/Class Screw Torque DN PN/Class Screw Torque

(Nm) 1 (Nm) 1
Dim. Quantity Dim. Quantity
80* 10, 16, 25 M16 8 65 300 10 M20 12 160
/150 5/8“ 4 120 16 M24 12 180
25 M27 16 205
/150 7/8“ 12 230
100 10,16 M16 8 80 350 10 M20 16 215
25 M20 8 95 16 M24 16 235
/150 5/8“ 8 70 25 M30 16 340
/150 1“ 12 280
125 10,16 M16 8 90 400 10 M24 16 240
25 M24 8 110 16 M27 16 300
/150 3/4“ 8 110 25 M33 16 445
/150 1“ 16 300
150 10,16 M20 8 120 450 10 M24 20 210
25 M24 8 140 16 M27 20 300
/150 3/4“ 8 130 25 M33 20 395
/150 1 1/8” 16 405
200 10 M20 8 175 500 10 M24 20 245
16 M20 12 120 16 M30 20 410
25 M24 12 140 25 M33 20 480
/150 3/4“ 8 180 /150 1 1/8“ 20 355

250 10 M20 12 140

16 M24 12 150
25 M27 12 200
/150 7/8“ 12 170

Tab.4-3 Fastening torque for flanges valve body

* DN80 only for MTV

1
The information in the table refers to lubricated bolts. The correction factor for new, unlubricated bolts is 1.5.
Tighten the bolts alternately until the correct tightening torque is reached.

Tightening torque applies to flat gaskets corresponding to non-reinforced and reinforced graphite according to
EN 12516-2: 2014 with m-factor according to ASME 2.0 to 2.5. Maximum thickness for gasket: 2.0 mm. Tightening
torque must not be exceeded, because then the functionality of the valve can be compromised. Tightening
torques in Nm are designed for gaskets according to EN 1514-1, ASME B16.21 and counter flanges according to
EN 1092-1, EN 1759-1, ASME B16.47.

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4.2.2 Recommended fastening torque for MTV/FSV stuffing box

Shaft ø Stuffing box ø Tightening torque, Tightening torque,

DN (mm) di/dy (mm) graphite stuffing box PTFE stuffing box
(Nm (Nm)
80*,100,125 20 20/30 6 10
150,200 25 25/35 10 10
250 30 30/40 12 15
300 35 35/45 15 15
350 40 40/55 25 25
400 50 50/65 40 35
500 60 60/75 60 50

* DN80 only for MTV

Tab.4-4 Torque for MTV/FSV stuffing box

The fastening torque at the table are valid for new, properly fixed stuffing boxes. If
the threads are not lubricated, the highest torque specifications are valid.

By leakage while operating, the compression of the stuffing box can be improved
by higher torque values.

Generally: To aviod a leakage, all the nuts have to be fastened the same, only little
differences at the torque are tolerated.

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4.2.3 Tightening torque for screws in valves

Screw dim./class M6 M8 M10 M12 M16 M20 M24 M27
Tightening torque MV 1) 10 Nm 25 Nm 47 Nm 57 Nm 140 Nm 273 Nm 472 Nm 682 Nm

1) Mv-recommendations refer to flat burr-free surfaces lubricated with a good quality lubricant.
Tab.4-5 Tightening Torque

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5 Assembly

5.1 Unpacking and transportation

Inspect the butterfly valve for transport damage when unpacking. The protective caps
must only be removed immediately before assembly. The valve must be stored on a
suitable base and protected against dirt until installed.

The valve must be stored in a cool, dry, clean place, not in direct contact with the floor.
The valve must always be protected against dirt during storage and assembly, see also
Technical Information sheet, Ti-935 that is available at www.somas.se.

Warning!
When transporting and handling the valve, observe the weight of the valve or of the whole unit.
Do not walk under suspended loads.

Transportation must be carried out with suitable hoisting equipment as shown in (➔ Fig.5-
1/a) and (➔ Fig.5-1/b). The picture shows a standard situation. Please note that all possible
situations that can occur cannot be covered in this lift instruction.

Fig.5-1/a Lifting Fig.5-1/b Lifting

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5.2 Installation of the valve in the pipeline

Attention!
The installation of the butterfly valve is usually made with full installed actuator. The assembly
is made by closing spring loaded and double acting actuators with closed butterfly valve, by
opening spring loaded actuators with open butterfly valve.
At opening spring loaded actuators, a short adapter with additional flanges is to be installed in
the pipeline immediately in front of and behind the valve.

Mounting in horizontal pipes

How Somas valves are mounted in a horizontal pipe can depend on a variety of factors like the
media, the application as such and available space.

Somas valves (ball valves, segmented valves and butterfly valves) should generally be mounted:

• In the first place with the shaft horizontally

• If it is necessary to deviate from above, the spindle should point upwards in the upper half plane

• For media that has a thick ”bottom fraction” that can accumulate in the lower shaft bearing,
avoid mounting with the shaft straight up or near straight up

• Mounting with the shaft pointing down in the lower half plane should be avoided, and especially
mounting with the shaft straight down

• If there are strong reasons for choosing the mountings that contradict the instructions above,
Somas should be contacted to evaluate the risks associated with these mountings

The direction of flow is indicated with arrows on the valve body. Fix the pipeline correctly to prevent
the exertion of external forces on the valve.

i
Note
The prefered flow direction is shown with arrows on the valve body (➔ Fig.5-2). The medium
should impact on the flat side of the disc.
End of line-installation of the valve is only permitted after approval from Somas.

Fig.5-2 Prefered flow direction marking

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Warning!
Before carrying out maintenance or repair work on the valve with actuator as well as installation
and disassembly of the butterfly valve in the pipeline, always disconnect the compressed air
supply to the actuator.
Single action actuators may move to “open” or “closed” position without being connected to the
air system.

5.2.1 Important information for installation

• The protective devices are to be removed directly before mounting the valve.

• Counterflanges must be in accordance to the European or ASME standards.

• Clean the whole pipeline system prior start up. Impurities damage the seat and the butterfly
edge and lead to leakage.

• Flush the pipeline system with fully opened valve.

• Use gaskets of an appropriate quality (no spiral-wound gasket).

• Check if all flange surfaces are clean and undamaged.

• Valves can be delivered with threaded connection holes intended for TA Luft, flushing,
lubrication, steam etc. Components and equipment to be connected shall fulfil the safety
requirements according to the PED (2014/68/EU).
Pipe threads with parallel threads and a separate sealing ring shall be used.

5.2.2 End of line installations

End of line-installation of the valve is only permitted after approval from Somas. When the valve
is installed “end of line”, it is important that the valve inlet (coverplate side) is facing towards the
piping. (➔ Fig.5-3).

Fig.5-3 Installing end of line

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• Check if all screws of the cover plate are tightened.

Do not pull the ends of the counterflange with force to the valves, to compensate wide clearances

In case of control application avoid mounting the butterfly valve direct behind or ahead of a pipe
bend. If the valve must be mounted behind a pipe bend, observe that the shaft is assembled aligned
to the bend to reduce dynamic, irregular forces on the butterfly (➔ Fig.5-4).

Fig.5-4 Installing near pipe bends Fig.5-5 Installing the butterfly valve after a centrifugal pump

To install the butterfly valve on the pressure side of a centrifugal pump, you have to position the
butterfly valve shaft perpendicular to the pump shaft (➔ Fig.5-5).

1. Make sure that the pipelines are flushed clean.

2. Open and close the valve completely before tightening the screws of the flange. Consider that
the butterfly valve opens 60°-80° by control applications and about 80° by shut-off function. To
seal the flanges tightly you have to use plain washers and tighten the screws in sequence with a
torque wrench. The fastening torque depends on the size of the screw (➔ Chap. 4.2).

3. If possible open the valve approx. 5° right before installing.

4. Make sure that the sealing areas of the counterflange are clean and parallel situated.

5. Make sure that the butterfly valve and the gaskets are correctly centered and that correct quality
is used. By a good shut-off function the pressure of the counterflange is transmitted through the
gasket to the cover plate (➔ Fig.5-6).

6. Tightening torque varies with the bolt dimension acc. to table (➔ Chap. 4.2).

7. The flange bolts must be tightened cross-wise acc. (➔ Fig.5-7)

8. NOTE! On the MTVL/FSVL valves, the bolts are first tightened on the cover plate side (inlet).

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Fig.5-6 Flanges and gaskets

4 bolts 8 bolts
1 5
1 3

8 3

4 7

4 2
6 2

12 bolts 16 bolts
1 5 1 9
16 5
12 9
8 13

8 3
12 3

4 11
4 7

14 7
10 11
6 15
6 2 10 2
Fig.5-7 Tightening flange bolts

5.3 Start up
1. Always start up the system only with closed butterfly valve.

2. Be sure that the system is clean before starting up. Impurities may damage the
seat immediately and in addition cause a leakage of the butterfly valve.

3. The valve should be fully opened at the last flushing by cleaning the system.

4. Check the stuffing box and in case of leakage, tighten the nuts of the stuffing
box gland (➔ Tab.4-4).

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5.4 Disassembly of the pneumatic actuator

i
Note
Observe also the detailed information in the operating manual of the actuator Mi-503EN.

Warning!
Before assembling or disassembling the pneumatic actuator of a butterfly valve installed in the
pipeline depressurise the relevant valve in the pipeline system, isolate the valve and remove the
medium before working on the valve.
The pressurised medium may lead to injuries to personnel.

Warning!
Before carrying out maintenance or repair work on the valve with actuator as well as installation
and disassembly of the butterfly valve in the pipeline, always disconnect the compressed air
supply to the actuator.
Single action actuators may move to “open” or “closed” position without being connected to the
air system.

33

22

11

44

55

66

1 Puller 3 Screw 5 Bolt

2 Driver 4 Clamping ring bolts 6 Bracket

Fig.5-8 Disassembly of the actuator (schematic diagram)

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Use a puller to disassemble the actuator from the butterfly valve. This prevents
damage to the seat and the butterfly of the valve.

Pullers
Actuator size A11 A13 A21 A22 A23 A24 A31 A32
Article no. 34786 34786 34786 34786 34786 34786 34787 34787
Actuator size A33 A34 A41 A42 A43 A44 A51 A52
Article no. 34787 34787 34788 34788 34788 34788 34788 34788

1. Undo the clamping ring bolts (➔ Fig.5-8/4).

2. Remove the accessory parts such as positioners and end position limit switches.

3. Remove the screws (➔ Fig.5-8/3), to remove the driver (➔ Fig.5-8/2).

4. Remove the bracket (➔ Fig.5-8/6) from the butterfly valve by removing the bolts
(➔ Fig.5-8/5).

5. Press the actuator off the valve with the puller (➔ Fig.5-8/1). Turn the puller in
until the actuator can be removed from the valve shaft.

6. Lift the actuator off and turn the puller out again.

5.5 Positioning of the shaft with disassembled actuator

3°

A groove or a line at the end of the shaft, marks the position of the disc in the
butterfly valve. The groove or line must be parallel to the butterfly valve body, when
the valve is closed and the key in the flow direction points to the right (➔ Fig.5-9).
Groove Line

3°

Fig.5-9 Marking (at the end of the shaft) Fig.5-10 Slot angle

To ensure that the valve in combination with an actuator without overtravel achieves
the closing position (➔ Fig.5-10) the slot of the key is turned out of the centre line
aprox. 3°.

The tightness of the butterfly valve depends on the closing torque.

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5.6 Assembly of the pneumatic actuator

i
Note
Observe also the detailed information in the operating manual of the actuator Mi-503EN.

Warning!
Before assembling or disassembling the pneumatic actuator of a butterfly valve installed in the
pipeline depressurise the relevant valve in the pipeline system, isolate the valve and remove the
medium before working on the valve.
The pressurised medium may lead to injuries to personnel.

Warning!
Before carrying out maintenance or repair work on the valve with actuator as well as installation
and disassembly of the butterfly in the pipeline, always disconnect the compressed air supply to
the actuator.
Single action actuators may move to “open” or “closed” position without being connected to the
air system.

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Danger!
Risk of injury!
Observe movements of the valve disc.
Keep hands, tools and other objects away from the area where the valve disc moves. The valve
with valve disc mounted may work as a cutting tool. Do not leave any foreign objects in the
valve body. The valve disc of the butterfly valve always works as a separate device. There is no
difference whether an actuator is installed or not. The position of the disc may change during
transport or handling of the butterfly valve.

1 2

3
4
5
6

1 End stop bolt 4 Clamping ring

2 End stop bolt 5 Bracket
3 Bolt 6 Bolt

Fig.5-11 Assembly of the actuator (schematic diagram)

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5.6.1 Actuator mounting alternatives

Following mounting positions are possible:

B D

C
Fig.5-12 Actuator mounting position

i
Note
To prevent damage, do not fit the actuator with force.

When large actuators (both single - and double acting) are used in vertical pipes, install them
with the cylinder in the pipe direction. This will result in less wear and easier maintenance.

1. Make sure that the butterfly valve is closed when using double acting and
closing spring loaded actuators.

2. Make sure that the butterfly valve is open when using opening spring loaded
actuators.

3. Lubricate the shaft and the key.

4. Fix the bracket to the actuator using the screws (➔ Fig.5-11/3).

5. Assemble the actuator with the bracket on the desired position (A, B, C or D)
(➔ Fig.5-12) onto the shaft of the butterfly valve body. Fix the unit with the
screws (➔ Fig.5-11/6).

6. Connect the shaft’s end of the butterfly valve to the actuator using the
clamping ring (➔ Fig.5-11/4). Assemble the clamping ring so that the yellow
markings show the position of the butterfly. When the valve is closed, the
markings must have an offset of 90° to the flow direction.

7. Tighten the bolts at the clamping ring (➔ Fig.5-11/4).

8. Adjust the end positions afterwards (➔Chap. 6.6).

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6 Maintenance

6.1 Disassembly of the butterfly valve from pipeline

Attention!
The disassembling of the butterfly valve is usually made with full installed actuator. The
disassembly is made by closing spring loaded and double acting actuators with closed butterfly
valve, by opening spring loaded actuators with open butterfly valve.
At opening spring loaded actuators, a short adapter with additional flanges is to be installed in
the pipeline immediately in front of and behind the valve.

Warning!
Before carrying out maintenance or repair work on the butterfly valve with actuator or
installation and removal of the butterfly valve from the pipeline, always disconnect the
compressed air supply to the actuator.
Single action actuators may move to “open” or “closed” position without being connected to the
air system.

Warning!
Inform yourself of the properties of the medium. Protect yourself and your environment from
hazardous or poisonous substances.
Observe the safety instructions in the safety data sheets of the manufacturers.
Ensure that no medium can enter the pipeline during maintenance work.

Warning!
Do not remove the valve from the line as long as the valve is under pressure!
Dismantling or disassembly of a valve under pressure leads to an uncontrolled pressure drop.
Always isolate the relevant valve in the pipeline system; depressurise the valve and remove the
medium before working on the valve.

Warning!
When transporting and handling the valve, observe the weight of the valve or of the whole unit.
Never lift the valve by its positioner, limit switch, solenoid valve or piping. Place the hoisting
ropes securely according to lift instruction.
The valve or parts thereof may injure persons if dropped.
Do not walk under suspended loads.

Procedure MTV

1. Seal off the pipeline section containing the butterfly valve.

2. Depressurise the sealed off pipeline section.

3. Drain the pipeline section.

4. If necessary purge the pipeline section.

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5. Set butterfly valves double acting actuators in closed position.

6. Remove the compressed air supply to the actuator.

7. Control the temperature of both pipeline and butterfly valve. Let cool down the pipeline
and the butterfly valve to the ambient temperature if necessary.

8. Ensure the butterfly valve against falling (➔ Fig.5-1/a).

9. If the butterfly valve is equipped with double acting or closing spring loaded actuators
dismantle the connection between valve and piping.

10. If the butterfly valve is equipped with an opening spring loaded actuator, remove
the compete butterfly valve with the spacers assembled on each side (➔ Chap. 5.2).

Procedure FSV

1. Close shut-off valves before and after the valve in question.

2. Depressurise the pipeline section in which the valve is installed.
3. Drain the medium from the pipeline.
4. Flush the pipeline section clean if necessary.
5. The valves must be closed during removal.
6. Secure the valve package to prevent it falling (➔ Fig. 5-1/b).

6.2 Maintenance
Regular maintenance is necessary to be able to operate the butterfly valve with maximum
efficiency and low operating costs. Somas products enable trouble-free operation and are very
low-maintenance.
Check the butterfly valve, the actuator/gear and accessory parts regularly to ensure safe, trouble-free
operation. The tightening torques of the boltings on the flanges must be checked in accordance with
the specifications of the gasket manufacturer and tightened if necessary. The stuffing box must be
checked regularly and re-tightened if necessary. The most important replacement parts
are contained in the Somas replacement part set. The gasket set contains all necessary seals and
sealing rings for basic repair of the valve.

i
Note
Note down the details of the type plate (➔ Fig.6-1) before contacting the contact partners given
in the order confirmation.
Only use original replacement and wear parts from Somas Instrument AB.

Fig.6-1 Type plate

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6.2.1 Procedure to evaluate a leakage on a butterfly valve with

pneumatic actuator installed in a pipeline

1. Open the butterfly valve entirely, to flush out existing particles on the sealing
areas.

2. Make sure that no impurities was clamped between the seat and the disc.

3. Close the butterfly valve.

1 2

1 End position bolt “open” position 2 End position bolt “closed” position 3 Type plate

Fig.6-2 End position bolts on pneumatic actuator

If the leakage remains futhermore, open the valve slightly:

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If the leakage remains futhermore, open the valve slightly:

Loosen the end position bolts “closed” (➔ Fig.6-2/2) of the pneumatic actuator and
turn this a fourth-turn anticlockwise. Test the valve. Repeat the procedure until
the valve is tight. If the end position bolt was loosend more than three turns, and
the butterfly valve remains leaking, the seat is damaged and has to be replaced.

Tighten the lock nut of the end position bolt, if the butterfly valve is tight.

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6.2.2 Procedure to evaluate a leakage on a butterfly valve with gear

installed in a pipeline

1. Open the butterfly valve entirely, to flush out existing particles on the sealing areas.

2. Make sure that no impurities was clamped between the seat and the disc.

3. Close the butterfly valve.

2
1

1 End position bolt “open” position 2 End position bolt “closed” position

Fig.6-3 End position bolts on gear actuator

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If the leakage remains futhermore, open the valve slightly:

Loosen the end position bolts “closed” (➔ Fig.6-3/2) of the worm gear actuator and
turn this a fourth-turn anticlockwise. Test the valve. Repeat the procedure until the
valve is tight. If the end position bolt was loosend more than three turns, and the
butterfly valve remains leaking, the seat is damaged and has to be replaced.

Tighten the lock nut of the end position bolt, if the butterfly valve is tight.

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6.3 Installation and disassembly of the stuffing box

1. Check the stuffing box after starting up and after this regularly. Retighten the nuts of the
stuffing box gland if necessary (➔ Fig.6-4/1).

The stuffing box package must be replaced if leaks can no longer be

eliminated by tightening the nuts.

Changing the stuffing box is normally a part of valve overhaul. Follow applicable safety instructions
concerning dismounting of the butterfly valve from pipeline (➔ Chap. 6.1) and dismounting the
pneumatic actuator from the ball segment valve (➔ Chap. 5.4).

When indicated it is possible to change the stuffing box if the butterfly valve is installed
in the pipeline. For this regard the following safety instructions.

Warning!
Before replacing the stuffing box of a butterfly valve installed in the pipeline depressurise
the relevant butterfly valve in the pipeline system, isolate the butterfly valve and remove the
medium before working on the butterfly valve.
The pressurised medium may lead to injuries to personnel.

Warning!
Before carrying out maintenance or repair work on the butterfly valve with actuator or
installation and removal of the butterfly valve from the pipeline, always disconnect the
compressed air supply to the actuator.
Single action actuators may move to “open” or “closed” position without being connected to the
air system.

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Installation and disassembly MTV/FSV

When using PTFE stuffing boxes, the actuator is always to be disassembled

(➔ Chap. 5.4).

When using graphite stuffing boxes, the actuator can remain installed. In this
case you can install the graphite rings by cutting through them at an angle and
then carefully pushing them over the shaft (➔ Fig.6-4/5).

1
2
3

4 5

1 Nut 3 Graphite/PTFE rings 5 Graphite rings

2 Stuffing box gland 4 Key

Fig.6-4 Assembly of the stuffing box

1. Remove the key (➔ Fig.6-4/4) and undo the nuts (➔ Fig.6-4/1).

2. Remove the stuffing box gland (➔ Fig.6-4/2) and insert the graphite rings
(➔ Fig.6-4/5).

3. Fix the stuffing box gland again with the nuts.

4. Tighten the nuts alternately, but not too tight.

5. Insert the new key.

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6.4 Replacing the seat (standard metal seat) MTV

To replace the seat, the complete valve assembly is dismounted from the pipeline
(➔ Chap. 6.1) and sometimes the actuator must also be removed from the valve (➔ Chap. 5.4).

Attention!
To change the seat, the butterfly valve has to be safely fixed in a fastening device!

Danger!
Risk of injury!
Observe movements of the disc.
Keep hands, tools and other objects away from the area where the disc moves when the
actuator is connected to compressed air system. Single action actuators may move to “open” or
“closed” position without being connected to the air system.

Warning!
Before carrying out maintenance or repair work on the valve with actuator as well as installation
and disassembly of the butterfly valve in the pipeline, always disconnect the compressed air
supply to the actuator.
Single action actuators may move to “open” or “closed” position without being connected to the
air system.

14

10

17

17 Screw 14 Seat
10 Cover plate

Fig.6-5 Replacing the seat

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6.4.1 Disassembly

i
Note
The replacement of the seat should be made with installed actuator.

Attention!
The seat disassembly is made by closing spring loaded and double acting actuators with closed
valve, by opening spring loaded actuators with open valve.

Procedure

1. Loosen the screws (➔ Fig.6-5/17) and remove the cover plate (➔ Fig.6-5/10).

2. Lift the seat (➔ Fig.6-5/14) out of the butterfly valve.

6.4.2 Cleaning, lubrication and assembly

1. Clean the seat area and cover plate and make sure that the disc periphery is
undamaged. Any damage can quickly destroy a new seat. Small scratches on
the disc edge can be removed by lightly polishing the edge with fine emery
cloth.

2. Lubricate the screws (➔ Fig.6-5/17) with molybdenum disulphide paste.

3. Insert in the new seat (➔ Fig.6-5/14).

4. Refit the cover plate (➔ Fig.6-5/10).

5. Tighten screws (➔ Fig.6-5/17) in rotating order.

6. Check the “closed” position of the butterfly valve and adjust if necessary by
setting the end position bolt on the actuator (➔ Chap. 6.6).

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6.5 Replacing the PTFE seat MTV

To replace the seat, the complete valve assembly is dismounted from the pipeline (➔ Chap. 6.1)
and sometimes the actuator must also be removed from the valve (➔ Chap. 5.4).

Attention!
To change the seat, the butterfly valve has to be safely fixed in a fastening device!

Danger!
Risk of injury!
Observe movements of the disc.
Keep hands, tools and other objects away from the area where the disc moves when the
actuator is connected to compressed air system. Single action actuators may move to “open” or
“closed” position without being connected to the air system.

Warning!
Before carrying out maintenance or repair work on the valve with actuator as well as installation
and disassembly of the butterfly valve in the pipeline, always disconnect the compressed air
supply to the actuator.
Single action actuators may move to “open” or “closed” position without being connected to the
air system.

14

10

17

17 Screw 14 Seat
10 Cover plate

Fig.6-6 Replacing the PTFE seat

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6.5.1 Disassembly

i
Note
The replacement of the seat should be made with installed actuator.

Attention!
The seat disassembly is made by closing spring loaded and double acting actuators with closed
valve, by opening spring loaded actuators with open valve.

Procedure

1. Loosen the screws (➔ Fig.6-6/17) and remove the cover plate (➔ Fig.6-6/10).

2. Remove the seat (➔ Fig.6-6/14).

6.5.2 Cleaning, lubrication and assembly

1. Clean the seat area and cover plate and make sure that the disc periphery is
undamaged. Any damage can quickly destroy a new seat. Small scratches on
the disc edge can be removed by lightly polishing the edge with fine emery
cloth.

2. Lubricate the screws (➔ Fig.6-6/17) with molybdenum disulphide paste.

3. Insert the new seat.

Attention!
Damage of the seat!

4. Refit the cover plate (➔ Fig.6-6/10).

5. Tighten screws (➔ Fig.6-6/17) in rotating order.

6. Check the “closed” position of the butterfly valve and adjust if necessary by
setting the end position bolt on the actuator (➔ Chap. 6.7).

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6.6 Replacing the Fire safe seat FSV

To replace the seat, the complete valve assembly is dismounted from the pipeline
(➔ Chap. 6.1) and sometimes the actuator/gear must also be removed from the valve.

Attention!
To change the seat, the butterfly valve has to be safely fixed in a fastening device!

Danger!
Injury risk!
Pay attention when the disc is moving.
When the actuator is connected, make sure that hands, tools and other objects are kept away
from the area around a disc that is moving. The disc in a butterfly valve may act as a cutting
tool. Do not leave any foreign objects in the valve housing. The disc in a butterfly valve always
operates as a separate unit. Whether or not an actuator is installed makes no difference. The
position of the disc may change during transportation or when the butterfly valve is handled.

33 9

32
10
14

11

9 Screw 14. PTFE-seat

10 Cover plate 32. Fire safe seat
11 Support ring 33. Guide ring

Fig.6-7 Replacing the Fire safe seat

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6.6.1 Disassembly

i
Note
The replacement of the seat should be made with installed manual gear unit.

Attention!
The seat disassembly is made by closing spring loaded and double acting actuators with closed
valve, by opening spring loaded actuators with open valve.

Procedure

1. Loosen the screws (➔ Fig.6-7/9) and remove the cover plate (➔ Fig.6-7/10).

2. Lift the Fire safe seat (➔ Fig.6-7/32) out of the butterfly valve.

3. Lift the PTFE-seat (➔ Fig.6-7/14) and the support ring (➔ Fig.6-7/11) and guide ring
(➔ Fig.6-7/33) out of the butterfly valve.

6.6.2 Cleaning, lubrication and assembly

1. Clean the seat area and cover plate and make sure that the disc periphery is undamaged. Any
damage can quickly destroy a new seat. Small scratches on the disc edge can be removed by
lightly polishing the edge with fine emery cloth.

2. Lubricate the screws (➔ Fig.6-7/9) with molybdenum disulphide paste.

3. Insert in the new PTFE-seat (➔ Fig.6-7/14) with the support ring (➔ Fig.6-7/11). Insert the guide
ring (➔ Fig.6-7/33). Insert the Fire safe seat (➔ Fig.6-7/32).

4. Refit the cover plate (➔ Fig.6-7/10).

5. Tighten screws (➔ Fig.6-7/9) in rotating order.

6. Check the “closed” position of the butterfly valve and adjust if necessary by setting the end
position bolt on the manual gear unit (➔ Chap. 6.8).

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6.7 Adjustment of the end positions on pneumatic actuator

Danger!
Risk of injury!
Observe movements of the disc.
Keep hands, tools and other objects away from the area where the disc moves when the
actuator is connected to compressed air system. Single action actuators may move to “open” or
“closed” position without being connected to the air system.

1 2

1 End position bolt “open” position 2 End position bolt “closed” position 3 Type plate

Fig.6-8 End position bolts on pneumatic actuator

Attention!
Damage to PTFE seats!
While adjusting disc valves equipped with PTFE seats keep attention not to close the valve to
firm. This causes damage to the seat!

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6.7.1 Setting of the “closed” position with type MTV

1. Connect compressed air via a pressure reduction valve. Adjust the pressure to 3 bar.

2. Operate the valve to test. Leave it in the closed position.

3. If the valve is not mounted in the pipe line, make a visual check the disc edge
is in contact with the seat.

4. If the valve is mounted in the pipe line, check for leakage across closed valve.

5. The design of the valve is such that increased surface pressure between seat
and disc will reduce leakage. Do not increase surface pressure more than
necessary.

6. If the points 4 or 5 above require some action please see procedure below.

Procedure

1. Loosen the nut of the end position bolt (➔ Fig.6-8/2) and turn the end position
bolt 0.25 turns counterclockwise.

2. Repeat point 2 above.

3. Repeat point 3 alternative 4 above.

4. When the set-up is correct, apply sealing tape and tighten the lock nut.

5. If the valve is outside the pipe line is preferable to make a leakage test
(Chap. 6.9).

6.7.2 Setting of the “open” position with type MTV

1. Connect compressed air via a pressure reducing valve 4-5,5 bar depending on
actuator specification.

2. Operate the valve to test.

3. Check if the valve opens to the desired position.

In case of shut off/on application the max. opening angle of the butterfly valve is about 80°.
In case of control application the max. opening angle is about 60°-80°.

Procedure

1. If the butterfly does not reach the position, loosen the lock nut of the end
position bolt and turn the end position bolt (➔ Fig.6-8/1) 1-2 turns
counterclockwise.

2. If the butterfly rides over the position, loosen the lock nut of the end position
bolt and turn the end position bolt (➔ Fig.6-8/1) 1-2 turns clockwise.

3. Operate the valve to test.

4. When the correct setting is reached, attach thread seal tape and tighten the locknut.

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6.8 Adjustment of the end positions on gear

Danger!
Risk of injury!
Observe movements of the disc.
Keep hands, tools and other objects away from the area where the disc moves when the
actuator is connected to compressed air system. Single action actuators may move to “open” or
“closed” position without being connected to the air system.

2
1

1 End position bolt “open” position 2 End position bolt “closed” position

Fig.6-9 End position bolts on gear actuator

Attention!
Damage to PTFE seats!
While adjusting disc valves equipped with PTFE seats keep attention not to close the valve to
firm. This causes damage to the seat!

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6.8.1 Setting of the “closed” position on the butterfly valve type MTV/FSV

1. Operate the valve to test.

2. Check if the butterfly touches the seat in the closed position.

3. The adjustment is correct if the butterfly touches the seat.

Procedure

1. If the butterfly does not touch the seat, loosen the lock nut of the end position
bolt (➔ Fig.6-9/2) and turn the end position bolt 1-2 turns counterclockwise.

2. If the contact pressure of the butterfly onto the seat is too high loosen the lock
nut of the end position bolt and turn the end position bolt (➔ Fig.6-9/2) 1-2 turns
clockwise.

3. Operate the valve to test.

4. When the set-up is correct, thighten the lock nut on the actuator.

5. The butterfly valve should undergo a leakage test subsequently (➔ Chap. 6.9).

6.8.2 Setting of the “open” position on the butterfly valve type MTV/FSV

1. Operate the valve to test.

2. Check if the valve opens to the desired position (about 80°).

In case of shut off/on application the max. opening angle of the butterfly valve is
about 80°.

Procedure

1. If the butterfly does not reach the position, loosen the lock nut of the
end position bolt and turn the end position bolt (➔ Fig.6-9/1) 1-2 turns
counterclockwise.

2. If the butterfly rides over the position, loosen the lock nut of the end position
bolt and turn the end position bolt (➔ Fig.6-9/1) 1-2 turns clockwise.

3. Operate the valve to test.

4. When the correct setting is reached, tighten the locknut.

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6.9 Leak test of the valve

Each valve should be tested for leakage after maintenance work on the seat.

Danger!
Risk of injury!
Observe movements of the disc.
Keep hands, tools and other objects away from the area where the disc moves when the
actuator is connected to compressed air system. Single action actuators may move to “open” or
“closed” position without being connected to the air system.

The valve has to be installed between the flanges for the test procedure with a
prescribed torque (➔ Tab.6-1).

1. The butterfly valve can be tested with a testing device as in (➔ Fig.6-10)

shown.

Please consult pressure testing instruction Mi-901 EN.

3
5
4
6

1 Piece of pipe 3 Flange gaskets 5 Butterfly valve

2 Counter flange 4 Blind flange 6 Water connection

Fig.6-10 Leak test device (schematic diagram for wafer valve types)

In case of leakage the valve must be adjusted again (➔ Chap. 6.9).

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Nominal Max. differential pressure Gaskets Force of Torque

size (closed valve) [mm] pressure
ø ø total
DN inside outside [t] [Nm]

80* 25 89 142 5 100-120

100 25 115 168 10 120-165
125 25 141 194 15 180-220
150 25 169 224 20 200-250
200 25 220 284 25 250-290
250 25 273 340 30 400-500
300 20 324 400 40 500-620
350 20 356 457 50 800-1000
400 20 407 514 65 1000-1350
500 15 508 624 100 1900-2700

Tab.6-1
* DN80 only for MTV

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6.10 Components

6.10.1 MTV DN 80-150, with metal seat

18

2
1
20
19

7
15
14 3

10

8
9 6
4

Fig.6-11 DN 80-150, with metal seat

1 Key 6 Stuffing box gland 10 Cover plate 19 Plug

2 Shaft 7 Valve body 14 Seat 20 Screw
3 Stud 8 Stuffing box kit 15 Disc
4 Nut 9 Screw 18 Gasket

Following parts are included in the sealing kit for valves with metal seat:
DN 80-150: Pos. No. 1, 8, 14 and 18.

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6.10.2 MTV DN 200-300, with metal seat

18
17

20
7
19
3
10
4
2

1
15 8
9 6
14

Fig.6-12 DN 200-300, with metal seat

1 Key 6 Stuffing box gland 10 Cover plate 18 Gasket

2 Shaft, upper (DN 200-500) 7 Valve body 14 Seat 19 Plug
3 Stud 8 Stuffing box kit 15 Disc 20 Screw
4 Nut 9 Screw 17 Shaft, lower (DN 200-500)

Following parts are included in the sealing kit for valves with metal seat:
DN 200-300: Pos. No. 1, 8, 14 and 18.

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6.10.3 MTV DN 350-500, with metal seat

18
17

20
7
19
21 3
4
10
9 2

15 1

8
6
23

14

Fig.6-13 DN 350-500, with metal seat

1 Key 6 Stuffing box gland 10 Cover plate 18 Gasket

2 Shaft, upper (DN 200-500) 7 Valve body 14 Seat 19 Plug
3 Stud 8 Stuffing box kit 15 Disc 20 Screw
4 Nut 9 Screw 17 Shaft, lower (DN 200-500) 23 Bearings

Following parts are included in the sealing kit for valves with metal seat:
DN 350-500: Pos. No. 1, 8, 14 and 18.

54
Original document - Mi-205 EN Edition: 2021-09

6.10.4 MTV DN 80-150, with PTFE seat

18

2
1
20
19

7
15
14
3
10

9 8
6
4

Fig.6-14 DN 80-150, with PTFE seat

1 Key 6 Stuffing box gland 10 Cover plate 19 Plug

2 Shaft, upper (DN 200-500) 7 Valve body 14 Seat complete 20 Screw
3 Stud 8 Stuffing box kit 15 Disc
4 Nut 9 Screw 18 Gasket

Following parts are included in the sealing kit for valves with PTFE seat:
DN 80-150: Pos. No. 1, 8, 14 and 18.

55
 Edition: 2021-09 Original document - Mi-205 EN

6.10.5 MTV DN 200-300, with PTFE seat

18
17

20
7
19
14 3
4
2

1
15
9 8
6
10

Fig.6-15 DN 200-300, with PTFE seat

1 Key 6 Stuffing box gland 10 Cover plate 19 Plug

2 Shaft, upper 7 Valve body 14 Seat complete 20 Screw
3 Stud 8 Stuffing box kit 15 Disc
4 Nut 9 Screw 18 Gasket

Following parts are included in the sealing kit for valves with PTFE seat:
DN 200-300: Pos. No. 1, 8, 14 and 18.

56
Original document - Mi-205 EN Edition: 2021-09

6.10.6 MTV DN 350-500, with PTFE seat

23
17

21
18 2
23

9
19
15 7

14

10 1
3

8
20 6
4

Fig.6-16 DN 350-500, with PTFE seat

1 Key 6 Gland 10 Cover plate 18 Gasket 23 Bearing

2 Shaft, upper 7 Valve body 14 Seat complete 19 Cover
3 Stud 8 Stuffing box 15 Disc 20 Screw
4 Nut 9 Screw 17 Shaft, lower 21 Cyl. pin

The following parts are included in sealing kits for valves with PTFE seats:
DN 350-500: Pos. no. 1, 8, 14 and 18.

57
 Edition: 2021-09 Original document - Mi-205 EN

6.10.7 FSV DN 100-150, with Fire safe seat

18

2
20
19
21

7
1
3

34
15
14
9
33 8
6
32
10 4

Fig.6-17 DN 100-150, with Fire safe seat

1 Key 6 Box gland 10 Cover plate 19 Plug 32 Fire safe seat

2 Shaft 7 Valve body 14 Seat complete 20 Screw 33 Guide ring
3 Stud 8 Stuffing box kit 15 Disc 21 Cyl. pin 34 Safety plate
4 Nut 9 Screw 18 Gasket

The following parts are included in sealing kits for valves with Fire safe seats:
DN 100-150: Pos. no. 1, 8, 14, 18, 32 and 33.

58
Original document - Mi-205 EN Edition: 2021-09

6.10.8 FSV DN 200-500, with Fire safe seat

18
17
20 21
19
7
23*

34
3
4 23*

15 2
8
14 6
33
32

10 1
9

Fig.6-18 DN 200-500, with Fire safe seat

1 Key 6 Box gland 10 Cover plate 19 Plug 32 Fire safe seat

2 Shaft 7 Valve body 14 Seat complete 20 Screw 33 Guide ring
3 Stud 8 Stuffing box kit 15 Disc 21 Cyl. pin 34 Safety plate
4 Nut 9 Screw 18 Gasket 23 Bearings DN 350-500*

The following parts are included in sealing kits for valves with Fire safe seats:
DN 200-500: Pos. no. 1, 8, 14, 18, 32 and 33.

*Optional

59
 Somas.se LinkedIn
Head office:
Somas Instrument AB
Norrlandsvägen 26
SE-661 40 SÄFFLE
Sweden

Phone: +46 (0)533 69 17 00

E-mail: sales@somas.se
www.somas.se