FLOWROX SKW Series Manual

SKW / SKF-2015-09-ENG
Original document language: English
Installation, operation and maintenance
instructions for Flowrox Slurry Knife Gate
valves SKW DN50 –600 (Wafer) and
SKF DN80 –600 (Flanged)
These instructions must be read carefully and
understood prior to the installation, use, and servicing
of this product.
N O T E
FLOWROX OY
P.O. Box 338
FI-53101 Lappeenranta, Finland
Tel. [phone] Fax [phone]
E-mail: [e-mail]
www.flowrox.com

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(”FLOWROX”) WHICH REMAINS THE SOLE OWNER OF THESE RIGHTS. OWNERSHIP OF THESE RIGHTS
ARE NOT TRANSFERRED FROM FLOWROX TO ANYONE IN CONNECTION WITH THIS MANUAL. THIS
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RENT OR LEASE.
THIS MANUAL PROVIDES INSTRUCTIONS TO CARRY OUT CERTAIN ACTIVITIES AND IS DESIGNED AND
MEANT TO GUIDE AND ASSIST PROFESSIONAL AND PROPERLY TRAINED EXPERTS IN PERFORMING
THEIR FUNCTIONS. EVERYONE MUST BECOME FAMILIAR WITH ALL INSTRTUCTIONS IN THIS MANUAL
BEFORE ANY INSTALLATION, USE, MAINTENANCE, REPAIR OR ANY OTHER ACTIONS OF THE
RESPECTIVE GOODS AND/OR SERVICES WHICH THIS MANUAL APPLIES TO. ALL INSTRUCTIONS MUST
BE FOLLOWED CAREFULLY. HOWEVER, OBSERVANCE OF ANY PART OF THE INSTRUCTIONS
PRESENTED IN THIS MANUAL MAY BE OMITTED IN EVENT WHEN IT IS REQUIRED OR ALLOWED BY
LAW
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FLOWROX IS THE TRADEMARK OF FLOWROX OY REGISTERED IN FINLAND AND IN OTHER
COUNTRIES. ALL OTHER TRADEMARKS, LOGOS, BRANDS AND MARKS DISPLAYED IN THIS MANUAL
ARE PROPERTY OF THE RESPECTIVE OWNERS UNLESS STATED OTHERWISE.
Copyright © 2015 Flowrox Oy. All rights reserved.

TABLE OF CONTENTS
1DIRECTIVE CONFORMANCE DECLARATIONS ............................................4
1.1 General safety instructions........................................................................ 5
2INTRODUCTION..............................................................................6
2.1 Applications and purpose of use ................................................................. 6
2.1.1 Restrictions on use for SKW and SKF valves .................................................. 6
2.1.2 Using the valve in explosive conditions ....................................................... 6
2.2 General description ................................................................................. 7
2.2.1 Principle of operation............................................................................ 7
2.2.2 Mechanical structure ............................................................................. 8
2.3 Technical data...................................................................................... 11
2.3.1 Product identification........................................................................... 11
2.3.2 Actuators ..........................................................................................12
3TRANSPORTATION, STORAGE AND LIFTING .......................................... 13
4INSTALLATION............................................................................. 14
4.1 General............................................................................................... 14
4.2 Flow direction, support, and valve position ................................................. 15
4.3 Valve installation .................................................................................. 16
4.4 Flushing installation guidelines................................................................. 17
5VALVE OPERATION........................................................................ 20
5.1 Commissioning and decommissioning ......................................................... 20
5.2 Flushing .............................................................................................. 20
6SERVICING AND MAINTENANCE ......................................................... 21
6.1 General maintenance and checks .............................................................. 21
6.1.1 Scheduled maintenance ........................................................................22
6.1.2 Spare parts ........................................................................................22
6.1.3 Lubrication ........................................................................................23
6.2 Changing the secondary seal .................................................................... 24
6.3 Changing the ring sleeves........................................................................ 25
6.4 Valve dismantling .................................................................................. 26
6.4.1 Removing the actuator, gate, and tower....................................................26
6.4.2 Dismantling the valve body ....................................................................27
6.5 Valve assembly ..................................................................................... 28
6.5.1 Valve body, secondary seal, and gate assembly ...........................................28
6.5.2 Tower and actuator assembly .................................................................29
6.5.3 Testing and adjusting the valve stroke ......................................................30
6.5.4 Final assembly and testing ..................................................................... 30
6.6 Troubleshooting.................................................................................... 31
Appendix A: Main measurements of SKW and SKF valves .......................................... 32

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SKW/ SKF-2015-09-ENG
1DIRECTIVE CONFORMANCE DECLARATIONS
FLOWROX OY
Marssitie 1
P.O. Box 338
FI-53101 Lappeenranta
Finland
Tel. [phone]
hereby declares that the Flowrox Slurry
Knife Gate valve, Wafer (SKW) and Slurry Knife Gate valve, Flanged (SKF)
comply with the following applicable regulations:
Pressure Equipment Directive 97/23/EC (PED):
Valves according to article 3, clause 3 (SEP); no CE-marking for conformity with PED.
European Union Machinery Directive 2006/42/EC and
Finnish Government Decree on Machine Safety, 400/2008, Machine Decree (koneasetus):
Annex IIB “partly complete machine”. No conformity with directive when valve is actuated manually.
Atex Directive 94/9/EC:
Conformity to directive declared only if Ex and CE are marked on valve nameplate. In that case a
separate Atex declaration is supplied.
Do not operate valve before conformity to machine directive 2006/42/EC has been declared for the
complete machine (pipeline) to what the valve is installed as a partly complete machine. Follow the
valve installation instructions in this manual. Conformance declarations for accessories (solenoid valve,
limit switches etc.) and actuators are supplied separately in component documentation. Risk analysis
responsible employee at Flowrox Oy is Jarmo Partanen.
On behalf of Flowrox Oy
In Lappeenranta, 1 September 2015
Jukka Koskela
President and CEO

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SKW/ SKF-2015-09-ENG
1.1 General safety instructions
The symbols in Table 1 are used in this manual to highlight the parts requiring particular
attention.
Table 1.Warning and safety signs.
Symbol
Description
Risk to personal safety:
Neglecting the safety measures can cause serious
injury or death.
Machinery or environmental risk:
Incorrect maintenance or operation of the product
can harm the environment or the product.
Read the operation and maintenance instructions:
Read and understand the operation and
maintenance instructions before using the product.
Prevent accidents and ensure the valve’s appropriate operation by complying with the
installation, safety, and maintenance instructions in this manual. Installation and
maintenance of the valve must be carried out by persons with appropriate training. Electrical
installation work of the actuator must be performed by a qualified electrician.
Access to the IOM-manual must be guaranteed at all times at the place of operation of the
valve. It is required to observe the IOM-manual in all work tasks for the valve.
Use personal protective equipment when performing any checks or maintenance operation for
the valve (goggles, helmet, clothing and gloves). Always follow the factory safety regulations.
In case of any discrepancies between translations, the English version shall prevail.
D AN G E R
W AR N I NG
N O T E

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SKW/ SKF-2015-09-ENG
2INTRODUCTION
2.1 Applications and purpose of use
Flowrox Slurry Knife Gate valves (SKW) and (SKF) are intended for industry medium and slurry
applications. They are bi-directional and are installed between flat flanges to shut-off or
open flow within instructed temperature and pressure limits.
2.1.1 Restrictions on use for SKW and SKF valves
The valve must not be used to throttle the flow in any way, nor should the gate be left in
partially opened or closed position as this will lead to premature failure.
The valve temperature and pressure range must not be exceeded. The temperature ranges
are given in Table 2 for standard sleeve materials. Check the pressure class from the valve
type plate. Do not use higher pipeline pressure than rated for the valve.
Table 2. Temperature ranges for SKW and SKF valves.
Ring sleeve material
NR
NBR
EPDM
Max valve operating
temperature (°C)
-40 to +75
-30 to +100
-40 to +120
2.1.2 Using the valve in explosive conditions
This valve type is not designed for Ex-areas.
For use in explosive conditions the valve must have the required Ex-classification and the
grounding cables must be connected to earth. Check actuator, solenoid valve, and limit
switch documentation for more information of use in explosive conditions.

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SKW/ SKF-2015-09-ENG
2.2 General description
2.2.1 Principle of operation
Flowrox SKW and SKF valves are built with a cast or welded body and feature a heavy-duty
stainless steel gate as a standard structure. Removable ring sleeves on both sides of the gate
provide a bi-directional bubble tight seal.
In the open position the two ring sleeves seal against each other in the centre of the valve,
providing a full bore through which the medium can travel. Main components are shown in
Figure 1. Closing the valve forces the gate progressively down between the two mating ring
sleeves, until it reaches the fully closed position. When the valve is fully closed, the ring
sleeves push against both sides of the gate, effectively sealing and completely containing the
line pressure. Any medium discharged between the ring sleeves during open/close strokes is
collected to the valve body cavity and drained or flushed trough the flushing ports.
The secondary seal is built in the upper part of the body. On every valve stroke, it wipes the
gate and lubricates it with silicone grease. Easier actuation and minimum wear are achieved.
There is no need to remove the valve from the line when replacing the secondary seal, but in
tight or unsafe conditions it is unavoidable.
Figure 1. Valve main components.
No.
Description
No.
Description
1
Valve body
7
Secondary seal
2
Gate
9
Protective plug (on flushing port)
3
Tower
12
Bottom cover plate
4
Ring sleeve
A
Valve body cavity

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SKW/ SKF-2015-09-ENG
The valve must not be used to throttle in any way,
nor should the gate be left in partially opened or
closed position as this will lead to premature
failure.
This valve is intended for on-off operation only. Ring sleeves are easily replaced, and are
available in a number of molded elastomer options to suit different conditions.
The gate speed may not exceed 25mm/s.
2.2.2 Mechanical structure
SKW and SKF valves can be delivered with the actuator options shown in Figure 2. Alternative
actuators. Manual actuator type depends on the valve size.
Figure 2. Alternative actuators
Type
Description
M
Manual actuator
MG
Manual actuator with gearbox
A
Pneumatic actuator
H
Hydraulic actuator
E
Electric actuator
W AR N I NG
W AR N I NG

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SKW/ SKF-2015-09-ENG
SKW valve part list is shown in Table 3 and the exploded view in Figure 3. Part quantities are
not displayed if they are valve size or actuator type dependent.
Figure 3.Exploled view of SKW valve
Table 3.SKW valve part list
Part
Qty
Description
Part
Qty
Description
1
1
Valve body
10
Bottom cover bolt
2
1
Gate
11
Bottom cover washer
3
1
Tower
12
1
Bottom cover plate
4
2
Ring sleeve (recommended spare part)
13
2
Locking pin
5
Tower mounting bolt
14
1
Clevis
6
Tower mounting washer
15
1
Clevis locking screw
7
1
Secondary seal (recommended spare part)
16
1
Clevis pin
8
4
Grease nipple
17
2
Retaining ring
9
2
Protective plug
18
PTFE sealing strip

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SKW/ SKF-2015-09-ENG
SKF valve part list is shown in Table 4 and the exploded view in Figure 4. Part quantities are
not displayed if they are valve size or actuator type dependent.
Figure 4.Exploled view of SKF valve
Table 4.SKF valve part list.
Part
Qty
Description
Part
Qty
Description
1
1
Valve body
10
Bottom cover bolt
2
1
Gate
11
Bottom cover washer
3
1
Tower
12
1
Bottom cover plate
4
2
Ring sleeve (recommended spare part)
13
2
Locking pin
5
Tower mounting bolt
14
1
Clevis
6
Tower mounting washer
15
1
Clevis locking screw
7
1
Secondary seal (recommended spare part)
16
1
Clevis pin
8
4
Grease nipple
17
2
Retaining ring
9
2
Protective plug
18
PTFE sealing strip

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SKW/ SKF-2015-09-ENG
2.3 Technical data
2.3.1 Product identification
Flowrox valve type plate is shown in Figure 5.
1. Valve type (see Table 5)
2. Serial number (year, order number,
series size, individual valve number)
3. Customer tag number etc.
4. Nominal diameter, pressure class
Figure 5.Valve type plate example.
Table 5.Valve model key table.
Type
Size
(DN)
Actuator
Pressure
class (PN)
-
Flange
drilling
Body
material
Gate
material
-
Ring sleeve
material
-
Auxiliaries
SKW =
Flowrox
Slurry Knife
Gate valve,
Wafer
SKF =
Flowrox
Slurry Knife
Gate valve,
Flanged
50-600
M = handwheel
MG = manual with
gearbox
A = pneumatic
AU = pneumatic
with pneumatic
spring
H = hydraulic
E = electric
10 = 10 bar
2 = DIN PN10
3 = DIN PN16
4 = DIN PN25
5 = DIN PN40
6 = ANSI150
7 = ANSI300
9 = other
0 = Cast iron /
Welded steel
2 = AISI 316
4 = other
S = AISI 316
Other on
request
COATING:
0 = nothing
NR = natural
rubber
NBR = nitrile
EPDM = ethylene
propylene diene
monomer
R = readiness for
inductive limits
R1 = AC/DC
R2 = DC, PNP
R3 = DC, NPN
Z1 = solenoid
valve, 24V DC
Z2 = solenoid
valve, 220V, 50/60
Hz
Z3 = solenoid
valve, 110V, 50/60
Hz
G = Gate guard
Examples: SKW100M10-60S0-NR-G
SKF100M10-60S0-NR-G
X = feature that is explained in the valve type plate.
The main dimensions and weight are given in Appendix A of this manual.

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SKW/ SKF-2015-09-ENG
2.3.2 Actuators
Standard actuators:
●Handwheel / handwheel with gearbox
●Pneumatic
●Hydraulic
●Electric
Manual actuator operation revolutions are shown in Table 6. Valves are closed by turning
clockwise.
Pneumatic actuators are with a fixed stroke and do not require external controls to position
the gate. The minimum supply pressure for pneumatically operated valves is 6 bars. Air must
be clean, waterless, lubricated and comply with ISO 8573-1:2001 Class 3.
Use correct sized pneumatic hoses to ensure sufficient air flow. Pneumatic actuator noise
level may exceed 85 dB and it is recommended to use ear protectors when working near the
valve.
Hydraulic actuators have a minimum supply pressure of 150 bars.
Electric actuators have open/close limit switches preset at the factory. A separate instruction
from the actuator manufacturer is always included in the shipment.
Please consult the manufacturer’s instructions on actuator requirements or/and limitations. If
actuator is changed or valve needs adjustment, follow the Maintenance instructions.
The gate speed may not exceed 25mm/s.
Table 6.Manually actuated valve operating revolutions.
Valve nominal size
DN
50
DN
80
DN
100
DN
150
DN
200
DN
250
DN
300
DN
350
DN
400
DN
450
DN
500
DN
600
Handwheel revs. to
stroke valve
18
25
28
40
50
60
-
-
-
-
-
-
Bevel gear revs. to
stroke valve
-
-
-
-
-
-
120
137
313
350
380
340
W AR N I NG

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SKW/ SKF-2015-09-ENG
3TRANSPORTATION, STORAGE AND LIFTING
Check and document any damage in packages or valves. Contact the transportation company
in case of damage. When new or unused valves are sitting idle for long periods, execute the
following procedures:
1. Prior to storage, thoroughly drain valves of any liquid.
2. Indoor storage is required. For unfavorable environment, cover the equipment with
protective tarpaulin that will allow proper air circulation.
3. Protect the equipment from temperature and humidity extremes and exposure to
excessive dust, moisture, vibration and sunlight.
4. It is preferred to store valves with the gate locked in open position.
5. Ensure pneumatic and hydraulic cylinder actuators have appropriate plugs installed in
the respective supply ports to prevent contamination of the cylinders.
6. Protect valve ring sleeves from heat, light and exposure to ozone.
7. Cover the flange openings.
8. Do not store any objects on the rubber ring sleeves.
9. Follow actuator instructions for storage.
10. Before start-up, clean the gate and lubricate the valve.
When storing used valves, wash the valve and also the body cavities with fresh water and
follow the steps above. For storage periods greater than 36 months, please contact Flowrox
as the rubber parts need to be changed before use.
Lifting equipment must be used for valves weighing
over 25kg.
Lift the valves securely from the tower (part 3 in Mechanical structure).
Bigger valves may have pre-installed lifting eyes which should be used
when available. When pre-installed lifting eyes are not available, use soft
straps to lift valve as shown in Figure 6.
Do not attach lifting equipment to the valve bore, handwheel, actuator,
locking pin holes or gate guards, as they can be damaged.
For valve dimensions and weight, refer to Appendix A.
Figure 6.Valve lifting example.
D AN G E R

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SKW/ SKF-2015-09-ENG
4INSTALLATION
Do not put your hands or fingers into the tower or
port areas when the valve cycles.
Do not use higher pressure than rated for the valve.
Higher pressures can cause serious damage to the
valve or harm to operating personnel.
Do not energize the actuator before the valve is
properly attached to the pipeline.
Never use the valve with all flushing ports plugged.
If the medium is harmful in any way, the flushing
port must be piped to a safe location.
4.1 General
Flowrox gate valves are normally delivered fully assembled and ready for use. Only personnel
with appropriate training are allowed to install the valves. If the valve is delivered without an
actuator or accessories, they must be installed in accordance with the manufacturer’s
instructions.
Flowrox gate valves have connections with DIN or ANSI bolt drillings as standard design, but
other drillings are also available, such as BS, AS, JIS.
Reserve enough space for safe installation and maintenance. See Appendix A for valve
dimensions. Notice that during opening and closing cycles, a small amount of medium is
discharged in the valve body cavity; therefore do not install gate valves above walkways or
critical components. Flushing and drainage connection must be installed if medium is harmful
or corrosive.
If the valve has been stored in the warehouse, lubricate the valve as instructed in the
Lubrication chapter.
D AN G E R
D AN G E R
D AN G E R
W AR N I NG

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SKW/ SKF-2015-09-ENG
4.2 Flow direction, support, and valve position
Do not step on a valve installed in horizontal or
angled position.
The valve does not have an intended flow direction; therefore it can be installed either way
in the pipeline.
Proper pipe support must be placed on either side of the valve to support the weight of the
pipe. The valve must never be used to support the pipes.
The valve can be installed in any position other than below horizontal. Flushing will not work
in installations below horizontal level and it will lead to leaking and nonfunctional valve. See
the following Figure 7.
Recommended installation positions
Forbidden installation positions
Figure 7. Installation alternatives for SKW and SKF valves.
D AN G E R
Do not install DN250 or larger pneumatically
actuated valves in other that vertical position
without support. This is to prevent possible
distortion of the actuator and valve tower.
W AR N I NG

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Horizontal installation.
Support is required as shown or otherwise.
Angled installation.
Support is required as shown or otherwise.
Figure 8. Support for pneumatically actuated valves.
4.3 Valve installation
At least the following must be ensured before valve installation:
●The pipeline is isolated from the process and there is no pressure in it.
●The pipeline is empty, clean, and cooled down.
●The pipeline flanges are parallel, concentric and with correct distance.
●The flange connection bolts size is correct. See Table 7.
●The valve is in OPEN position.
Follow these Installation steps:
1. Disconnect automatic actuator from power supply if connected.
2. Install the safety guards and required accessories to the valve
3. Lift the valve on place with appropriate lifting equipment.
4. Tighten the flange connection bolts evenly in a crosswise sequence shown in Figure 9.
Recommended tightening torque is shown in Table 7.
5. Other than mentioned flange drillings are also available.
Always support DN250 and larger pneumatically actuated valves (Figure 8).
6. Connect automatic actuator to power supply.
7. Connect flushing connection (if applicable).
8. Check that all connections have been fastened and the actuator is installed correctly.
9. Run a few open/close cycles without pressure in the pipeline. Refer to
Troubleshooting if the valve does not operate smoothly or without extra force.

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SKW/ SKF-2015-09-ENG
Table 7.Valve connection maximum tightening torque and bolt nominal diameter for steel flanges.
Valve size
(DN)
Recommended tightening
torque for flange bolt
Nm (ft-lbs)
Tapped hole
depth in body
(mm)
DIN
Bolt nominal
diameter
ANSI150
Bolt nominal
diameter
50
43 (32)
12
M16
5/8”-11 UNC
80
43 (32)
14
M16
5/8”-11 UNC
100
43 (32)
14
M16
5/8”-11 UNC
150
75 (55)
16
M20
3/4”-10 UNC
200
75 (55)
23
M20
3/4”-10 UNC
250
120 (90)
23
M20
7/8”-9 UNC
300
120 (90)
24
M20
7/8”-9 UNC
350
185 (135)
24
M20
1”-8 UNC
400
185 (135)
30
M24
1”-8 UNC
450
260 (190)
28
M24
1-1/8”-7 UNC
500
260 (190)
42
M24
1-1/8”-7 UNC
600
260 (190)
42
M27
1-1/4”-7 UNC
Figure 9.Flange bolt tightening example.
4.4 Flushing installation guidelines
Never use the valve with all flushing ports plugged.
If the medium is harmful in any way, the flushing
port must be piped to a safe location.
When valve flushing is required, customers need to provide the plumbing. The valves are
shipped with plugs installed in the flushing holes. Contact Flowrox office for process specific
instructions.
The concept of flushing is to ensure the valve does not jam due to accumulation of medium
solids in the valve body. Flushing line or drain line is also required if the medium is harmful to
people, environment or other components nearby. In other cases, the flushing connections
can be opened to prevent valve body from clogging up.
Reclaim service water is usually clean enough to accomplish the water flush, if clean water is
not readily available.
W AR N I NG

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SKW/ SKF-2015-09-ENG
Larger diameter valves can have additional flushing connection to ensure proper flushing.
Flushing connection are on the sides, bottom or on the face of the valve. Hole sizes are shown
in Appendix A. One or more flushing connections are used, depending on the process.
A flow indicator can be installed to the flushing line for easier function check-out.
In flushing example 1 the valve protective plugs (9) are removed or bottom cover plate (12)
is removed. The process medium slipping between the gate and ring sleeves during valve
operation flows freely out of the valve. If the medium is harmful in any way, the flushing port
must be piped to a safe location.
9. Protective plug
12. Bottom cover plate
Figure 10. Flushing example 1.

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SKW/ SKF-2015-09-ENG
In flushing example 2 (Figure 11), the water is supplied to one side and drained from the
other side of the valve. It is necessary to have a shut-off valve (B) on the upstream or supply
side of the flush water line to prevent water running constantly. This can be located
anywhere, but is usually near to the valve.
12. Bottom cover plate
A. Flush water supply
B. Shut-off valve
C. Drain line
Figure 11. Flushing example 2.

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5VALVE OPERATION
5.1 Commissioning and decommissioning
Before the valve is operated within the pipeline, ensure that it has been installed in
accordance with this manual and applicable safety regulations.
The following must also be ensured:
●Parameters on the type plate are suitable for the process and environment
●The valve is used for the purpose specified at the time of sales
●Required gate guards and other accessories are installed
●Possible explosive conditions have been taken into account
When a valve is decommissioned, dispose the valve parts and electric/pneumatic/hydraulic
devices (actuators) according to the local regulations and the instructions given by the part or
device manufacturer. Collect and dispose dangerous process media, so that people and
environment are not endangered. Follow the local regulations.
5.2 Flushing
Follow these operation instructions, when valve flushing is installed.
Flush Fowrox gate valves at least after every 20 cycles to keep the body clear of solids,
depending on application and process. If slurry solids are present in the process, the flushing
sequence needs to be initiated each time the valve is operated.
It is important to open the water supply valve a moment before the valve is operated. The
flushing water is then left on for the entire cycle and for a minimum of 10 seconds after the
cycle. To improve flushing, the water should be left on until clean flushing water is
exhausting through the drain line.