Emerson Hytork XL Series User manual

Installation, Operation and Maintenance Manual
MAC050515 EN Rev. 0
November 2022
Hytork XL Pneumatic Actuator

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Notes
November 2022
Installation, Operation and Maintenance Manual
MAC050515 EN Rev. 0

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Installation, Operation and Maintenance Manual
MAC050515 EN Rev. 0
Table of Contents
November 2022
Table of Contents
Table of Contents
Section 1: Important Safety Procedures
Important Safety Procedures...................................................................................1
Section 2: ATEX Instructions for Use in (Potential)
Explosive Areas
2.1 Intended Use................................................................................................. 3
2.2 Safety Instructions ........................................................................................ 3
2.3 Temperature Range for (Potential) Explosive Areas........................................ 4
Section 3: Operating Media, Pressures and Temperatures
3.1 Operating Media ........................................................................................... 5
3.2 Operating Temperature Range...................................................................... 5
Section 4: Actuator to Valve Installation
4.1 Bi-directional Travel Stops ............................................................................. 6
4.2 Travel Stop Adjustment Procedure ................................................................ 7
Section 5: Piping Instructions
Piping Instructions...................................................................................................8
Section 6: Solenoid Valves on Spring-Return Actuators
Solenoid Valves on Spring-Return Actuators.............................................................9
Section 7: Position Feedback
Position Feedback..................................................................................................10
Section 8: Spares Recommendations
Spares Recommendations......................................................................................11
Section 9: Disassembly Procedure
9.1 End Cap and Springs Disassembly on Spring-Return Actuators .................... 12
9.2 Changing Spring Sets on XL26 to XL681...................................................... 13
9.3 End Cap Disassembly on Double-Acting Actuators...................................... 13
9.4 Piston Disassembly...................................................................................... 13
9.5 Pinion Disassembly ..................................................................................... 13
9.6 Inspection................................................................................................... 13

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Table of Contents
November 2022
Installation, Operation and Maintenance Manual
MAC050515 EN Rev. 0
Table of Contents
Section 10: Assembly Instructions
10.1 Grease Instructions ..................................................................................... 14
10.2 Pinion Assembly.......................................................................................... 15
10.3 Alignment of Pinion for Correct Piston Assembly......................................... 15
10.4 Piston Assembly.......................................................................................... 16
10.4.1 Clockwise Rotation........................................................................... 16
10.4.2 Counterclockwise Rotation .............................................................. 16
10.5 Travel Stop Assembly .................................................................................. 16
10.6 End Cap Assembly on Double-Acting Actuators .......................................... 17
10.7 Spring-Return Actuators ............................................................................. 17
10.7.1 Spring Set Adjustments .................................................................... 17
10.7.2 Installing the Spring and End Cap ..................................................... 18
Section 11: Bottom Mounted Stop Block
11.1 The Hytork Solution.................................................................................... 20
11.2 Basic Stop Block Assembly........................................................................... 20
11.3 General Notes when Fitting to Valves .......................................................... 21
11.3.1 Double-Acting.................................................................................. 21
11.3.2 Standard Conguration Fail-Safe Clockwise ...................................... 21
11.3.3 Reverse Action Fail-Safe Counterclockwise ....................................... 22
11.4 Actuator Conventions for the Normal Position............................................. 22
11.4.1 Double-Acting.................................................................................. 22
11.4.2 Spring-Return................................................................................... 22
11.5 Assembly to Valves for Standard Rotation Conguration ............................. 22
11.5.1 Double-Acting and Fail-Safe Clockwise............................................. 22
11.5.2 Stop Adjustment (Fail Closed)........................................................... 23
11.6 Assembly to Valves for Reverse Action Conguration .................................. 24
11.7 Long Shaft Adaptor Dimensions and Materials............................................. 24
11.8 Adjustment of the Bottom Mounted Stop Block .......................................... 25
Section 12: Testing the Hytork Actuator
Testing the Hytork Actuator...................................................................................26
Section 13: Retractor Rods
13.1 Spring Removal System Board..................................................................... 27
Section 14: Service
Service...................................................................................................................28
Section 15: Parts and Materials
Parts and Materials.................................................................................................29

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Installation, Operation and Maintenance Manual
MAC050515 EN Rev. 0
Important Safety Procedures 1
Section 1: Important Safety Procedures
Section 1: Important Safety Procedures
Table 1. Applicable Models
XL 26 XL 281 XL 2586
XL 71 XL 426 XL 4581
XL 131 XL 681 -
XL 186 XL 1127 -
XL 221 XL 1372 -
Hytork XL actuators are only intended for use in large-scale xed installations excluded
from the scope of Directive 2011/65/EU on the restriction of the use of certain hazardous
substances in electrical and electronic equipment (RoHS 2).
Installation, adjustment, putting into service, use, assembly, disassembly, and maintenance
of the actuator is strictly reserved to qualied personnel.
Before installation, operation and maintenance, read the relevant sections of:
• This manual
• Quick Reference Guide: DOC.QRG.XL
! CAUTION
• Always disconnect the air and electrical supplies before carrying out any form of
maintenance on an actuator.
• When removing any ball valve or plug valve assemblies from a pipe system,
isolate the piping system on which the actuator is installed and relieve any media
pressure that may be trapped in the valve cavities before removing the actuator
for maintenance.
• Always contain the spring tension with Hytork retractor rods as explained in
Section 9.1 (Disassembly Procedure). Follow instructions for using the retractor
rod carefully. Only Hytork manufactured or approved retractor rods are to be
used for spring removal. As with any threaded tool that is frequently used retractor
rods should be checked to ensure that the threads are not worn or damaged in any
way and greased regularly. Any damaged or worn rods must not be used and must
be destroyed.
• Never attempt to “BLOW OUT” the pistons or the end caps from the actuator body
by using air pressure.
• Never turn the stop screws completely out when the actuator is under pressure.

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Important Safety Procedures2
Section 1: Important Safety Procedures
Numbers in brackets (#) refer to parts on the exploded view drawing (refer to Section 15,
Figure 13). All Hytork XL spares kits are supplied with SAFEKEY assemblies (13/14) cut to an
exact length which will t the circumference of the end cap (21) when fully assembled into
the actuator.
Any shortened SAFEKEY must not be used.
If in doubt, contact Emerson or your local Hytork Stocking Distributor. Read the relevant
sections carefully before continuing.
NOTE:
• Failure to follow proper storage guidelines will void warranty.
• Warehouse storage: Hytork actuators should be stored in a clean, dry warehouse,
free from excessive vibration and rapid temperature changes. Actuators should
not be stored on any oor surface.
• On site storage: Hytork actuators should be stored in a clean, dry warehouse, free
from excessive vibration and rapid temperature changes. Prevent moisture or dirt
entering the actuator. Plug or seal both air connection ports.
! WARNING
• Use lifting equipment as required by national or local legislation.
• Use lifting straps to lift the assembly of actuator and valve.
• Do not attach lifting straps to only the actuator, to lift the assembly of actuator
and valve.
Table 2. Weight of Actuators
Model Double-Acting Spring-Return with S80 Springs
kg lb kg lb
XL26 1.39 3.06 1.53 3.37
XL71 2.39 5.27 2.78 6.13
XL131 3.90 8.60 4.76 10.49
XL186 4.77 10.52 5.45 12.02
XL221 6.19 13.65 7.76 17.11
XL281 7.02 15.47 9.90 21.83
XL426 7.30 16.10 12.50 27.56
XL681 8.80 19.40 22.50 49.60
XL1127 22.00 48.50 36.00 79.37
XL1372 27.00 59.52 46.60 102.73
XL2586 46.00 101.41 79.00 174.16
XL4581 83.00 182.98 142.00 313.05

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ATEX Instructions in Explosive Areas 3
Section 2: ATEX Instructions in Explosive Areas
Section 2: ATEX Instructions for Use in
(Potential) Explosive Areas
2.1 Intended Use
T he Hytork XL series pneumatic actuators are a Group II category 2 equipment and
intended for use in areas in which explosive atmospheres caused by mixtures of air and
gases, vapours, mists or by air/dusts are likely to occur. Therefore, it may be used in (ATEX)
classied Zones 1, 2 (Gases) and/or 21, 22 (Dust).
2.2 Safety Instructions
1. Actuator assembly, disassembly, and maintenance is allowed only in absence of
explosive mixture.
2. Prevent entry of explosive mixtures into the actuator. We suggest utilizing a
solenoid with a “breather” function on Spring-Return actuators when used in
potentially explosive atmospheres.
3. The plastic position indicator caps are approved for ATEX gas group IIB areas.
— In areas where ATEX gas group IIC requirements apply, the plastic
indicator for actuator sizes XL26 to 281 is approved for use.
— In areas where ATEX gas group IIC requirements apply, do not use the
plastic position indicator cap for actuator sizes XL426 up to XL4581, to
avoid build up of static electricity.
4. In order to avoid increasing dust explosion risk, periodically clean dust deposits
from all equipment.
5. When equipment is installed in a hazardous area location (potentially explosive
atmosphere), prevent sparks by proper tool selection and avoiding other types of
impact energy.
6. Proper care must be taken to avoid generation of static electricity on the
non-conductive external surfaces of the equipment (e.g. rubbing of surfaces, etc.).
7. Hytork XL actuators do not have an inherent ignition source due to electro-static
discharge, but explosion hazard may be present due to the discharge of static
electricity from other valve assembly components.
— To avoid personal injury or property damage, make sure that the valve is
grounded to the pipeline before placing the valve assembly into service.
— Use and maintain alternate shaft-to-valve body bonding, such as a
shaft-to-body bonding strap assembly.
8. The paint protection must not exceed 200 μm if the actuator is used in a group
IIC atmosphere. For group IIA or IIB atmospheres, the paint protection must not
exceed a thickness of 2 mm (0.08 inch).

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ATEX Instructions in Explosive Areas
4
Section 2: ATEX Instructions in Explosive Areas
! WARNING
The actuator’s surface temperature is dependent upon process operating conditions.
If the actuator's surface temperature exceeds the acceptable temperature for the
hazardous area classication, it can catch re or in worst case can explode causing personal
injury and property damage. To avoid an increase of instrumentation and/or accessory
surface temperature due to process operating conditions, ensure adequate ventilation,
shielding, or insulation of these actuator components installed in a potentially hazardous
or explosive atmosphere.
NOTE:
The specied values are valid with the following conditions:
— Maximum working frequency of the actuator is 1 Hz at a maximum of 50 cycles per hour and at
maximum load.
Temperature
Valid for actuator model
Ambient range ATEX class TX (ATEX surface
temperature)
-20 °C to +75 °C T6 T85 °C (185 °F)
Standard temperature models-20 °C to +80 °C T5 T90 °C (194 °F)
-20 °C to +80 °C T1 to T4 T90 °C (194 °F)
-20 °C to +75 °C T6 T85 °C (185 °F)
High temperature models-20 °C to +90 °C T5 T100 °C (212 °F)
-20 °C to +120 °C T1 to T4 T130 °C (266 °F)
-40 °C to +75 °C T6 T85 °C (185 °F)
Low temperature models-40 °C to +80 °C T5 T90 °C (194 °F)
-40 °C to +80 °C T1 to T4 T90 °C (194 °F)
-20 °C to +250 °C for
2 hours T2 T260 °C (500 °F) Tunnel application models
2.3 Temperature Range for (Potential)
Explosive Areas
Table 3. Actuator model classication according to maximum
surface temperature

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Operating Media, Pressures and Temperatures 5
Section 3: Operating Media, Pressures and Temperatures
Section 3: Operating Media, Pressures
and Temperatures
3.1 Operating Media
1. Use clean, dry, or lubricated air or inert gas.
2. Maximum pressure: 8 bar/116 psi.
NOTE:
On applications where the spring stroke of single acting actuators is pneumatically
operated, the maximum pressure is 6.5 bar/95 psi.
3. Dew point 10 K below operating temperature.
4. For subzero applications take appropriate measures.
3.2 Operating Temperature Range
Using standard seals and grease the operating temperature range is -20 °C to +100 °C
(-4 °F to +212 °F) as is indicated on the product label. Other medias and temperatures may
be used but consult your local Hytork supplier for conrmation as to suitability.

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6Actuator to Valve Installation
Section 4: Actuator to Valve Installation
Section 4: Actuator to Valve Installation
The pinion drive, coupling device, and valve stem should be centered and concentric to
prevent any side loading to the pinion radial bearing and valve stem seat area. Ensure that
the coupling shaft to be operated is a tight but free sliding t into the female drive in the
actuator pinion (19).
4.1 Bi-directional Travel Stops
Hytork XL actuators have two travel stops (22, 23, and 24) for setting accurately the travel
and the open and closed positions. XL2586 and XL4581 can be tted with the optional
bottom stop block for setting the travel.
The actuator has a factory set stroke of 90°. The adjustable stroke range of the actuator is:
• at closed (0°) position: -3° to +7°
• at open (90°) position: -83° to +93°
NOTE:
If the actuator is assembled for reverse operation, instead of standard operation, Stop “1”
will adjust the “open” position and stop “2” the “closed” position (refer to Figure 1).
Figure 1 Travel Stops
“2” “1”
Stop marked Stop marked
View from top
“2”“1”

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7Actuator to Valve Installation
Section 4: Actuator to Valve Installation
4.2 Travel Stop Adjustment Procedure
1. Operate valve/actuator assembly to the open position.
2. Remove air supply.
3. Slacken locknut (24) on the “closed” stop (Marked “2” in Figure 1).
4. Turn the “closed” stop clockwise to reduce or counterclockwise to increase
the travel.
5. Tighten the lock nut.
6. Connect air and check that the position is correct. If not, repeat from Step 2.
7. Operate valve/actuator assembly to the “closed” position.
8. Remove air supply.
9. Adjust “open” travel stop (Marked “1” in Figure 1) as from step 3 to 6.

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8Piping Instructions
Section 5: Piping Instructions
Section 5: Piping Instructions
All actuators can be either piped with solid or exible tubing with the solenoid valve
mounted remotely from the actuator or by mounting a NAMUR designed solenoid valve
DIRECTLY onto the NAMUR mounting pad on the side of the actuator (refer to Figure 2).
Spring-Return actuator
operation
Double-Acting actuator
operation
Figure 2 Solenoid Operation

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9Solenoid Valves
Section 6: Solenoid Valves
Section 6: Solenoid Valves on
Spring-Return Actuators
It is recommended that on Spring-Return actuators, the Hytork “CATS” solenoid valves are
used. These valves are specially designed to prevent contamination of the internals of the
actuator by dirt from the atmosphere. This increases the working life of the actuator which
reduces down time and maintenance periods (refer to Figure 3).
Spring stroke operation Air stroke operation
Figure 3 Hytork “CATS”Solenoid Valve

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10 Position Feedback
Section 7: Position Feedback
Section 7: Position Feedback
All position feedback or positioning accesories that comply to the VDI/VDE 3845 (NAMUR)
standard, can be mounted easily on top of Hytork XL actuators. To access the pinion top,
remove the position indicator.

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11Spares Recommendations
Section 8: Spares Recommendations
Section 8: Spares Recommendations
When disassembling and carrying out maintenance work on the XL actuator, a Hytork
spares kit must be used to replace all O-Rings, DURASTRIP bearings, washers etc. This kit is
available from Emerson or its Stocking Distributors.

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12 Disassembly Procedure
Section 9: Disassembly Procedure
Section 9: Disassembly Procedure
9.1 End Cap and Springs Disassembly on
Spring-Return Actuators
1. Release locking nuts (24) and remove both travel stops (22) and thread seals (23)
or O-Rings (23a).
2. Remove the indicator (7) from the top of the pinion (19) For XL26 to XL221
use an allen key size 4 mm. For the larger sizes, the indicator can by pulled from
the pinion top.
3. Remove both sealing bolts (28) and O-Ring (29) from the end caps (21).
4. Place both the Hytork retractor rods through the hole in the end caps and screw
the rods into:
— For XL 26 to XL 681 the Pistons (20).
— For XL 1127 to XL4581 the retractor plate (20a, refer to Figure 4) until
travel is stopped (DO NOT OVERTIGHTEN) and take care the nut and
washer being free of the end cap face.
5. Turn back the rod 1/2 turn.
6. Screw the adjusting nut and washer by hand clockwise down the retractor rod
until they come up against the face of the end cap.
7. Prevent the “hold-nuts” to rotate by one wrench. Use another wrench, to screw
both adjusting nuts half turn at a time (refer to Figure 4) clockwise down the rods
until the end cap loosens (Maximum; approximately two complete turns).
This draws the:
— For XL 26 to XL681 the Pistons (20).
— For XL 1127 to XL4581 the retractor plate (refer to Figure 4) to the end
caps (21) and compresses the springs. This spring-compression, releases
the spring force and unlocks the SAFEKEY for removal.
8. Rotate the caps to ensure that the springs are retracted; if the cap will not turn
easily, a gentle tapping with a plastic hammer against the endcap will loosen the
end cap.
9. Unscrew the two slotted SAFEKEYS (13/14), and gently pull each SAFEKEY from
the body. If the SAFEKEY resists removal, gently tap the end cap with a soft
hammer to assist release.
10. When both SAFEKEYS have been removed, use a wrench to rotate the pinion,
driving the pistons (20) apart until they partially push the end caps from the body.
— For XL 26 to XL681 the Pistons (20), springs and end cap will come out.
— For XL 1127 to XL4581 the retractor plate (20a), springs and end cap will
come out.
11. To keep the spring pack assembly intact (refer to Figure 4), leave the retractor
rod in place. To disassemble the spring pack, unscrew the adjusting nut on the
retractor rod relieving the spring force, while preventing the rod from turning with
a wrench on the hold nuts.

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13Disassembly Procedure
Section 9: Disassembly Procedure
9.2 Changing Spring Sets on XL26 to XL681
I f only the springs set of the actuator has to be changed, perform steps 1 to 9. These steps
can be performed at both end caps simultaneously or at one end cap only. After step 9,
unscrew the adjusting nut on the retractor rod relieving the spring force while preventing the
rod from turning with a wrench on the hold nuts.
9.3 End Cap Disassembly on Double-Acting Actuators
Remove the SAFEKEY as described previously. The retractor rod is not required for
Double-Acting actuators. Remove the end caps by pulling them free from the body
keeping them square to the end face of the body (11).
9.4 Piston Disassembly
Rotate the pinion using a wrench to drive the pistons apart and remove from the body by
pulling the pistons.
9.5 Pinion Disassembly
Remove the snap ring (Circlip) (6), thrust washer (25) and DURASTRIP thrust bearing (5)
from the top of the pinion and CAREFULLY push the pinion from the body through the
bottom. Take care that the pinion does not damage the pinion bores on removal.
If necessary, remove any burrs, etc. from the top of the pinion before removal.
Carefully remove pinion top bearing (9) from the body.
9.6 Inspection
Clean and examine all parts for damage and wear. Emerson recommends O-Rings,
DURASTRIP bearings, SAFEKEYS, washers, etc. are replaced using a Hytork XL spares kit.
1
2/3
4
5
6
7
1
2/3
4
5
6
4
4
End cap disassembly
steps XL26 to XL681
End cap disassembly
steps XL1127 to XL4581
Extractor rods
Extractor
plates
Hold nuts
Adjusting nut
Figure 4 End Cap Disassembly

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14 Assembly Instructions
Section 10: Assembly Instructions
Section 10: Assembly Instructions
10.1 Grease Instructions
NOTE:
Check the product coding on the actuator’s product labels to dene which type of grease
to use.
Table 4. Recommended Grease
Table 5. Grease Instructions
Part Section of part Amount of grease
O-Rings
A Completely Light lm
Housing Parts
B Piston bore Light lm
C Top pinion bore Light lm
D Bottom pinion bore Light lm
Piston Parts
E O-Ring and bearing groove Light lm
F Rack teeth Half the teeth depth full with grease
G Piston bearing Light lm on outside
H Piston rack bearing strip Light lm
Piston Parts
J Pinion bottom and O-Ring groove Light lm
K Pinion top and O-Ring groove Light lm
L Gear teeth Half the teeth depth
M Pinion top bearing Light lm (inside and out)
N Pinion bottom bearing Light lm (inside and out)
Standard temperature -20 °C to +80 °C/-4 °F to +176 °F or
High temperature -10 °C to +120 °C/+14 °F to +250 °F
Current grease Formerly called
Castrol High Temperature Castrol LMX
Rocol Sapphire Premier Sapphire HI-TEMP 2
Castrol Spheerol EPL 2 BP Energrease LS-EP2
Total Ceran XM 220 Total Ceran WR2
Low Temperature: -40 °C to +80 °C/-40 °F to +176 °F
Castrol Optitemp LG2
SKF – LGLT 2
FUCHS – Renolit Unitemp 2

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15Assembly Instructions
Section 10: Assembly Instructions
10.2 Pinion Assembly
1. Lightly grease all O-Rings, O-Ring grooves, bearing grooves, and pinion.
2. Assemble the top pinion bearing (9) to the pinion, ensuring that the recess
openings are facing away from the gear form, then assemble items (8), (17),
and (18).
3. Lightly grease the pinion bores in the body (11) and insert the pinion being careful
not to damage the O-Rings.
NOTE:
The snap ring (Circlip) (6) has one side with bevelled edges which must go DOWN onto the
thrust washer (25); the square edge side must face UPWARDS.
4. When the pinion is in place, install the DURASTRIP thrust bearing (5), thrust washer
(25) and the snap ring (Circlip) (6) into the narrow groove at the top of the pinion
(ensuring the snap ring ts properly into the groove).
5. Only open the snap ring (Circlip) (6) enough to just clear the pinion diameter
as opening too far will damage the snap ring. If damage occurs replace with a
new part.
Piston assembly for
“Standard”operation
Pinion dot
One body dot for
standard mode
Piston assembly for
“Reverse”operation
Two body dots for
reverse mode
Pinion dot
10.3 Alignment of Pinion for Correct
Piston Assembly
Standard rotation is clockwise with the pistons moving towards each other (when viewed
from above the slot at the top of the pinion, refer to Figure 5).
Figure 5 Pinion Alignment
(a) (b)

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16 Assembly Instructions
Section 10: Assembly Instructions
10.4 Piston Assembly
10.4.1 Clockwise Rotation
(Pistons moving inwards, refer to Figure 5 [a]).
1. Align the pinion by lining up the center of the NAMUR slot in the top of the pinion
with the single dot on the body. The top of the pinion is marked with a single
identication dot to indicate the correct orientation of the stop faces.
2. Lightly grease all piston grooves, gear form and piston O-Rings (4) and t the
O-Ring (4) and wear ring (3) to the piston.
3. Fit the bearing block (10) to the back of the piston.
4. Grease the actuator body bore.
5. Insert the pistons into the bore, ensuring the piston racks line up with the
pinion gear. (The part number in the front face of the piston must be lined up
parallel to the pinion).
6. Push both pistons together until they are both in contact with the pinion, so that
when the pinion is rotated clockwise the pistons are drawn together. When the
pistons are together and the racks are correctly engaged with the pinion, the top
pinion drive ats should be at right angles to the axis of the body.
10.4.2 Counterclockwise Rotation
(Pistons moving inwards, refer to Figure 5 [b]).
Align the NAMUR slot in the top of the pinion with the two dots on the body and assemble
the pistons so that the pinion rotates counterclockwise as the pistons are drawn together.
10.5 Travel Stop Assembly
(Refer to Figure 1)
1. With the pistons together, screw in the CLOSING (cast identity number 2) travel
stop (22), complete with locking nut (24) and thread seal (23), until it comes into
contact with the pinion stop face.
2. Rotate the pinion through 90ø only, driving the pistons apart and screw in the
OPENING (cast identity number 1) travel stop (22), complete with locking nut and
thread seal, until it comes into contact with the pinion stop face. For individual
position requirements, see Section 4.