Paladon DGS Series Guide

Doc : Q056 Issued By : J Haworth
Rev : 2 Approved by : M Shepherd
Page : 1 of 24 Date Issued : 06/11/19
INSTALLATION, COMMISSIONING & MAINTENANCE
MANUAL
DGS, DGD & DGC-Series
Direct Gas or Nitro
g
en Bottle Scotch-Yoke Valve Actuators

DGS, DGD & DGC Series Valve Actuators
Doc : Q056 Issued By : J Haworth
Rev : 2 Approved by : M Shepherd
Page : 2 of 24 Date Issued : 06/11/19
Contents Page
1. Introduction ............................................................................................................3
2. Inspection Requirements on Initial Receipt of Actuator................................................3
3. Storage Requirements..................................................................................................3
3.1 Short-Term Storage ..........................................................................................3
3.2 Long-Term Storage...........................................................................................3
4. Actuator Overview ........................................................................................................4
4.1 Standard Components......................................................................................4
4.1.1 Frame..................................................................................................4
4.1.2 Direct Gas Cylinder.............................................................................4
4.1.3 End Stop Screws.................................................................................4
4.1.4 Local Position Indicator.......................................................................4
4.2 Optional Components .......................................................................................4
4.2.1 Spring Cylinder....................................................................................4
4.2.2 Manual Override..................................................................................5
5. Model Number Designations ........................................................................................5
6. Tool Requirements .......................................................................................................5
7. Valve/Actuator Mounting...............................................................................................5
8. Adjusting Open and Closed Valve Positions ................................................................7
9. Preparations for Start-Up..............................................................................................7
10. Manual Override Operation ..........................................................................................8
10.1 Double-Acting Actuator with Handwheel Type Manual Override......................8
10.2 Double-Acting Actuator with Handpump Type Manual Override.......................8
10.3 Spring Return Actuator with Handwheel Type Manual Override.......................8
11. Maintenance ............................................................................................................9
12. Direct Gas Cylinder Seal Replacement........................................................................9
13. Lubrication ..........................................................................................................11
14. Supply Fluid .........................................................................................................11
15. Replacement Seal Kits ...............................................................................................11
15.1 Direct Gas Spares Kits....................................................................................11
15.2 Frame Spares Kits ..........................................................................................11
16. Trouble-Shooting........................................................................................................12
17. Drawings ..........................................................................................................13
17.1 XXX-XXX-FRXXX-00-002-PL .........................................................................14
17.2 HYX-XXX-CYXXX-00-001-PL.........................................................................15
17.3 XXX-XXX-SRXXX-00-001-PL.........................................................................16
17.4 HY-DA ..........................................................................................................17
17.5 HY-DA-HW......................................................................................................18
17.6 HYX-XXX-HDXXX-00-001-PL.........................................................................19
17.7 HYX-XXX-CYXXX-00-002-PL.........................................................................20
17.8 HY-SRC ..........................................................................................................21
17.9 HY-SRC-JS.....................................................................................................22
17.10 XXX-XXX-SHXXX-00-001-PL.........................................................................23
18. Spares Kit Ordering & Additional Service Support .....................................................24

DGS, DGD & DGC Series Valve Actuators
Doc : Q056 Issued By : J Haworth
Rev : 2 Approved by : M Shepherd
Page : 3 of 24 Date Issued : 06/11/19
IMPORTANT NOTE: DIRECT GAS ACTUATORS CAN BE OPERATED BY GAS SUPPLY
LINE OR BY NITROGEN BOTTLES.
1. Introduction
This manual is designed to allow a qualified user to install, commission and maintain Paladon
Systems Ltd DGS, DGD and DGC Series valve actuators. This manual should be used in
conjunction with any additional documentation supplied at the time of shipping. Current
versions of all Paladon Systems Ltd documentation are available from
www.paladonsystems.com.
It is the user’s responsibility to ensure that all applicable Health and Safety Legislation is
followed when undertaking any service work. This manual is not designed to supersede or
replace any user’s plant safety or work procedures; in the event of any conflict, please contact
Paladon Systems Ltd or an authorised distributor.
2. Inspection Requirements on Initial Receipt of Actuator
Check paint to ensure that no damage has occurred during transit. In the event of any
paint damage, thoroughly clean the applicable area(s) and repaint as required.
Check that the information detailed on the actuator’s tag plate (comprises of the actuator
serial number, model number, maximum torque output, direct gas supply pressure range
and valve tag number) matches those detailed on the Sales Order Acknowledgement, Test
Certificates and Delivery Note. In the event of any discrepancies, please contact Paladon
Systems Ltd or an authorised distributor.
3. Storage Requirements
3.1 Short-Term Storage
To ensure optimum performance, the following should be undertaken prior to actuator
storage for any duration:
Check that all direct gas and electrical connections are suitably sealed to prevent
any environmental ingress.
For any actuator not yet assembled to a valve, place actuator on a wooden pallet to
prevent any damage to the valve coupling flange.
3.2 Long-Term Storage
In addition to the short-term storage requirements detailed above, for long-term
storage the following should be undertaken:
Protect the coupling parts (stem adaptor and coupling joint, coupling flange etc)
with grease or protective oil.
Keep actuators dry and protected against the direct action of weather elements.
Stroke the actuator and ensure all direct gas and electrical connections are
properly sealed after.

DGS, DGD & DGC Series Valve Actuators
Doc : Q056 Issued By : J Haworth
Rev : 2 Approved by : M Shepherd
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4. Actuator Overview
DGS, DGD and DGC Series direct gas valve actuators are suitable for use with quarter-turn
valves or mechanisms, and have been designed to provide years of efficient and reliable
operation in heavy-duty applications.
The main components of DGS, DGD and DGC Series valve actuators are:
4.1 Standard Components
4.1.1 Frame
The frame contains the scotch-yoke mechanism which converts the linear
movement of the direct gas piston into a quarter-turn rotary movement. To
protect personnel from injury and the scotch-yoke mechanism from corrosion,
the frame is a fully enclosed carbon steel fabricated construction. To support
the transverse forces generated by scotch-yoke mechanisms, and to ensure
correct alignment of the piston rod, sliding blocks and yoke bushing, the body
also contains a chromium plated guide bar.
4.1.2 Direct Gas Cylinder
Contains the direct gas piston, which generates the linear movement which is
converted into a quarter-turn rotary movement by the scotch yoke mechanism
housed in the actuator body.
4.1.3 End Stop Screws
Allow precise adjustment of a scotch-yoke mechanism’s angular stroke by
means of two end stop screws. One end stop screw is always located on the
end flange of the direct gas cylinder. For double-acting actuators, the
remaining end stop screw is either located on the body’s blanking flange, or in
the event a manual override is fitted, on the manual override. For spring-return
actuators, the remaining end stop screw is located on the outer spring-cylinder
flange, or in the event a manual override is fitted, on the manual override.
4.1.4 Local Position Indicator
Connected directly to the scotch-yoke mechanism, the local position indicator
protrudes through the top of the body to provide precise local visual indication
of the actuator’s angular position.
4.2 Optional Components
4.2.1 Spring Cylinder
Supplied with all spring-return DGS, DGD and DGC Series valve actuators, the
spring cylinder comprises of a scragged pre-compressed spring contained
within a fully welded carbon steel container.
WARNING! The spring cylinder is non-serviceable; any attempt to
disassemble it may result in serious injury or death.

DGS, DGD & DGC Series Valve Actuators
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4.2.2 Manual Override
There are two types of manual override mechanisms which can be provided;
Jackscrew or Hydraulic Handpump. Jackscrew type manual overrides
comprise of a handwheel and jackscrew to create a linear motion, which is
converted to a rotary motion via the scotch-yoke mechanism. Hydraulic
handpump manual overrides comprise of a hydraulic cylinder and handpump to
create a linear motion, which is converted to a rotary motion via the scotch-
yoke mechanism.
5. Model Number Designations
6. Tool Requirements
No special tools are required for the installation, commissioning and maintenance of Paladon
Systems Ltd actuators.
7. Valve/Actuator Mounting
Valve mounting is achieved through one of the following:
Direct mounting using threaded holes on the actuator’s body flange.
Stem adapter mounting using an adapter and coupling joint.

DGS, DGD & DGC Series Valve Actuators
Doc : Q056 Issued By : J Haworth
Rev : 2 Approved by : M Shepherd
Page : 6 of 24 Date Issued : 06/11/19
Paladon Systems Ltd actuators can be mounted in any orientation; however, it is common
industry practice to align the centreline of the actuator’s direct gas cylinder with that of the
valve pipework.
NOTE: Certain control components require mounting in a specific orientation with
respect to gravity in order to function correctly.
To assemble the actuator to the valve:
7.1 Check that the coupling dimensions of the actuator are suitable for those of the
valve flange and stem.
7.2 Move the valve to the open or closed position to match the rest position of the
actuator.
7.3 Thoroughly clean all mounting flanges, taking special care to ensure that all
grease is removed.
7.4 To assist with assembly, lubricate the valve stem with suitable oil or grease.
7.5 Lift the actuator by its lifting eyes and, if possible, ensure that the valve stem is
in the vertical position.
NOTE: Do not lift the actuator using slings around the actuator’s direct
gas or spring cylinders; doing so may result in damage.
7.6 If valve mounting is via a stem adapter and coupling joint (supplied loose),
assemble the coupling joint to the valve stem before proceeding further.
7.7 Lower the actuator onto the valve so that the valve stem slips in the actuator’s
yoke. Fasten the actuator to the valve by means of stud bolts, which are
screwed into the valve’s coupling flange.
7.8 Tighten the nuts to the stud bolts in accordance with the following torques:
Thread Size Torque
M8 20 Nm
M10 40 Nm
M12 70 Nm
M14 110 Nm
M16 160 Nm
M20 320 Nm
M22 420 Nm
M24 550 Nm
M27 800 Nm
M30 1100 Nm
M33 1400 Nm
M36 1700 Nm
7.9 Stroke the actuator to ensure smooth and full opening and closing of the valve.

DGS, DGD & DGC Series Valve Actuators
Doc : Q056 Issued By : J Haworth
Rev : 2 Approved by : M Shepherd
Page : 7 of 24 Date Issued : 06/11/19
8. Adjusting Open and Closed Valve Positions
The precise valve open and closed positions are set using the end stop screws. NOTE:
Certain valves incorporate their own end stops. For these types of valves, it is
recommended that the valve's end stops be adjusted to their maximum travel so that
the valve’s end positions are achieved using the actuator’s end stop screws only.
To adjust the open and closed valve positions:
8.1 Loosen the protective nut on each of the end stop screws.
8.2 Move the actuator yoke away from the applicable end stop screw.
8.3 Screw the applicable end stop screw to reduce the actuator’s angular stroke,
unscrew to increase it.
8.4 Move the actuator yoke towards the applicable end stop screw.
NOTE: During actuator stroking, a small loss of gas through the end stop
screw located on the direct gas cylinder is to be expected.
8.5 Check valve position and repeat steps 2 to 4 until desired valve position is
reached.
8.6 Tighten the protective nut on the applicable end stop screw.
8.7 Repeat steps 8.2 to 8.6 for the remaining end stop screw.
9. Preparations for Start-Up
Direct Gas Connections & Considerations
9.1 Prior to connecting the direct gas supply line(s), check that all pipes and fittings
are in accordance with the plant specifications.
9.2 Check that all direct gas supply lines are free of any contaminants or debris,
and that they are suitably supported to minimise any stress caused by
vibration.
9.3 Connect the direct gas supply line fasteners.
9.4 Pressurize direct gas cylinder. Check fasteners for any leaks, and ensure that
they are sufficiently tightened to avoid the chance of becoming loose due to
any vibrations created during operation.
Electrical Connections & Considerations
NOTE: All electrical connections are the responsibility of the user.
9.5 For installations in hazardous areas, ensure all electrical fittings have the
correct hazardous area certification.
9.6 Ensure that the actuators and any control components are suitably protected
against lightning strikes, electrical surges and spikes; and any magnetic fields.

DGS, DGD & DGC Series Valve Actuators
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Actuator Stroking
9.7 Stroke the actuator to check that smooth and continuous operation is achieved.
In the event of uneven stroking, or stroking speeds below those detailed on the
test certificate; first check to ensure correct gas supply pressure and flow rate.
Further fault finding procedures can be found in Section 16.
10. Manual Override Operation
10.1 Double-Acting Actuator with Handwheel Type Manual Override
(See Section 17.6, Drg. HYX-XXX-HDXXX-00-001-PL)
a. Isolate direct gas supply, depressurise actuator and control system.
b. Remove tubing and fittings from actuator supply inlets to ensure that both sides of
the piston are free to ‘breathe’ to atmosphere.
c. Move the lever on the handwheel frame mounting flange to the ‘ENGAGED’
position.
d. Rotate the handwheel clockwise to close, or anti-clockwise to open the valve.
e. Once the desired valve position has been achieved, disengage the manual
override by moving the lever on the handwheel frame mounting flange to the
‘DISENGAGED’ position.
f. Re-connect direct gas supply connections.
10.2 Double-Acting Actuator with Handpump Type Manual Override
(See Section 17.7, Drg. HYX-XXX-CYXXX-00-001-PL)
a. Isolate direct gas supply, depressurise actuator and control system.
b. Remove tubing and fittings from actuator supply inlets to ensure that both sides of
the piston are free to ‘breathe’ to atmosphere.
c. Move the 3-way ball valve and cylinder link ball valve levers to the horizontal
position.
d. Move the handpump selector valve to the required flow direction.
e. Operate handpump until desired valve position is achieved.
f. Return 3-way ball valve, cylinder link ball valve and handpump selector valves to
automatic position.
g. Re-connect direct gas supply lines.
10.3 Spring Return Actuator with Handwheel Type Manual Override
(See Section 17.10, Drg. XXX-XXX-SHXXX-00-001-PL)
a. Isolate direct gas supply, depressurise actuator and control system.
b. Remove tubing and fittings from actuator supply inlet to ensure that both sides of
the piston are free to ‘breathe’ to atmosphere.

DGS, DGD & DGC Series Valve Actuators
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c. Ensure actuator is in its fail position.
d. Rotate the handwheel anti-clockwise to open the actuator (for fail close ‘SRC’
actuators) or in clockwise direction to close the actuator (for fail open ‘SRO’ type
actuators).
e. Before restoring automatic direct gas operation, rotate the handwheel in the
opposite direction to the above bullet in order to move the actuator to its fail
position.
f. Reconnect direct gas supply lines.
11. Maintenance
11.1 All Paladon Systems Ltd actuators have been designed to provide long service
with minimum maintenance; however, a preventative maintenance program is
recommended. Preventative maintenance programs not only help avoid
unanticipated and costly down time, but also typically reduce the overall cost of
ownership.
11.2 It is the user’s responsibility to ensure that all applicable health and safety
legislation is followed when undertaking any maintenance work.
11.3 WARNING! Before commencing any maintenance work, the actuator’s
direct gas supply line, actuator and associated controls must be fully
depressurised. After system depressurisation, the actuator and controls
must be isolated from the supply line, and from any remote control
signals. Failure to follow any of these steps may result in unanticipated
actuator and valve movement, possibly resulting in serious injury or
death.
11.4 Any unauthorised maintenance or modification to the actuator and, where
applicable, the control system may invalidate the warranty.
11.5 Periodic inspection is recommended, specifically;
That smooth valve operation is maintained, and within the required stroking
time.
That there is no external damage to any components.
The direct gas supply pressure is kept within the specified range.
Direct gas connections do not show any signs of leakage.
Paint system remains undamaged.
That any dirt or debris is removed from actuator surfaces.
12. Direct Gas Cylinder Seal Replacement
NOTE: Ensure direct gas system is de-pressurised and isolated prior to
removing any parts from pressure cylinder.
12.1 Remove the bottom flange retaining nuts (see Section 17.2, Drg. HYX-XXX-
CYXXX-00-001-PL, Item 8 – commercial part).

DGS, DGD & DGC Series Valve Actuators
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12.2 Remove the bottom flange (see Section 17.2, Drg. HYX-XXX-CYXXX-00-001-
PL, Item 5 – manufactured part).
12.3 Slide off the cylinder liner (see Section 17.2, Drg. HYX-XXX-CYXXX-00-001-
PL, Item 1 – manufactured part).
12.4 Remove the frame cover retaining screws (see Section 17.1, Drg. XXX-XXX-
FRXXX-00-002-PL, Item 1 – commercial part).
12.5 Remove the frame cover (see Section 17.1, Drg. XXX-XXX-FRXXX-00-002-PL,
Item 2 – manufactured part).
12.6 Loosen the tie rods (see Section 17.2, Drg. HYX-XXX-CYXXX-00-001-PL, Item
6 – manufactured part).
12.7 Unscrew the piston rod and slide it off (see Section 17.2, Drg. HYX-XXX-
CYXXX-00-001-PL, Item 3 – manufactured part).
12.8 Unscrew the frame fixing screws (see Section 17.2, Drg. HYX-XXX-CYXXX-00-
001-PL, Item 10 – commercial part).
12.9 Remove the head flange (see Section 17.2, Drg. HYX-XXX-CYXXX-00-001-PL,
Item 4 – manufactured part).
12.10 Remove the O-rings, the piston scraper, the sliding rings, the gaskets; and
clean all O-ring grooves (see Section 17.2, Drg. HYX-XXX-CYXXX-00-001-PL,
Items 1, 2, 4, 5 & 6 – commercial part).
12.11 Replace all seals with new ones, and ensure that they are lubricated with
grease (see Section 17.2, Drg. HYX-XXX-CYXXX-00-001-PL, Items 1, 2, 4, 5 &
6 – commercial part).
12.12 Re-assemble the piston rod (see Section 17.2, Drg. HYX-XXX-CYXXX-00-001-
PL, Item 3 – manufactured part) by screwing it into the guide block (see Section
17.1, Drg. XXX-XXX-FRXXX-00-002-PL, Item 6 – manufactured part).
12.13 Tighten the tie rods (see Section 17.2, Drg. HYX-XXX-CYXXX-00-001-PL, Item
6 – manufactured part).
12.14 Re-assemble the cylinder liner (see Section 17.2, Drg. HYX-XXX-CYXXX-00-
001-PL, Item 1 – manufactured part) and bottom flange (see Section 17.2, Drg.
HYX-XXX-CYXXX-00-001-PL, Item 5 – manufactured part).
12.15 Uniformly tighten the bottom flange retaining nuts (see Section 17.2, Drg. HYX-
XXX-CYXXX-00-001-PL, Item 8 – commercial part).
12.16 Replace the paste gasket of the mechanism cover (see Section 17.1, Drg.
XXX-XXX-FRXXX-00-002-PL, Items 1 & 2 – manufactured part).
12.17 Replace the frame cover (see Section 17.1, Drg. XXX-XXX-FRXXX-00-002-PL,
Item 2 – manufactured part).
12.18 Replace and tighten the frame cover retaining screws (see Section 17.1, Drg.
XXX-XXX-FRXXX-00-002-PL, Item 1 – commercial part).