Robotarm II™

G-Series
Pneumatic & Hydraulic
Actuators
Five-Year Warranty
Severe Service Rated
Tension-Lok™
Powr-Swivl™
Acculine™ Shaft Drive
True Modular Design
Wear and Corrosion Resistant
Environmentally Sealed
Safety
NAMUR
Type Approved
ISO 9001
Versatile
Design and Construction

Introduction
For more than 40 years, Bettis Manual Hydraulic
has combined its ingenuity with Pump System
high quality standards, continu- Pneumatic
ously pioneering valve actuator Power
technology. Beginning with the Module
Robotarm scotch-yoke concept,
Bettis’ innovations have become
today’s standards for valve con-
trol in virtually every part of the
world. The company operates in Tandem
accordance with ISO 9001 and Pneumatic
BS-5750 certifications and main- Power Module
tains a formal Total Quality Man-
agement program to assure
product excellence. Continuing
our innovative tradition, Bettis Pneumatic Power
introduces the latest valve Module with
Extended
automation advancement…the
Travel Stop
G-Series Robotarm II™ quarter- Drive
turn actuator. Module
Hydraulic
Product Concept Power Module
In developing the G-Series
actuators, Bettis improved a
basic concept — the Reaction Created with its user’s interest environmental conditions.
Bar, by adding our new state-of- in mind, the G-Series actuators Proper actuator selection,
the-art Powr-Swivl™, replaceable offer many significant benefits. enhanced by proprietary data
bearings, highly efficient wear Among these are: analysis methods, allows opti-
and corrosion resistant coating • Wear Resistance – The mum performance and operat-
system, and tension rod com- G-Series Powr-Swivl piston rod ing economy.
pressed spring. This enhanced connection is contained by the • Replaceable Bearings – Low
design greatly improves effi- guide block, which is sup- friction, permanently lubri-
ciency, reduces wear and ported by a high strength alloy cated, high performance bear-
extends the actuator’s life. The steel reaction bar treated to ings protect sliding and
combining of these technologies, provide a highly corrosion and rotating components, signifi-
enhancements, and superior wear resistant finish. The Powr- cantly extending actuator life.
quality control techniques pro- Swivl, superior surface fin- • Five Year Warranty – G-Series
duced an assembly which ishes, and self-lubricating actuators are backed by the
became the heart of our new bearings maximize the transfer industry’s strongest materials
extended service actuators — of input energy directly to the and workmanship warranty.
the G-Series. valve stem. The tension loaded • Corrosion Resistance –
spring minimizes radial loads G-Series actuators incorporate
Advantages on the piston rod, further protective internal and external
enhancing efficiency. coatings, assuring the actua-
The G-Series actuators provide • Service Rated – G-Series tor’s reliable operation in the
a unique, highly reliable means models are qualified by accel- harshest of environments. The
of operating ball, butterfly, or erated wearage testing. The actuator exhibits excellent cor-
plug valves, as well as louvers, actual service life may be pre- rosion resistance, confirmed
dampers and other 90 degree dicted based upon specific by Salt Spray Testing per
rotating mechanisms. application parameters and ASTM B117 criteria. Construc

2
 Blind End Cap • Efficient Modular Inventory –
All modules may be pur-
chased separately or in any
combination. This feature
Spring allows reduced parts and
Module spares inventory at the distri-
bution facility, while substan-
Spring Module tially increasing the
with Extended availability of different model
Travel Stop configurations.
Extended •NAMUR – The shaft driven
Spring Module
with Integral Travel Stop accessory interface conforms
Hydraulic to the NAMUR standard and
Override is identical on all G-Series
Cylinder actuators, allowing for stan-
dardization of accessory
Pneumatic
mounting hardware and
Power installation practices.
Double-Acting
Module • MSS and ISO Valve Mounting
Hydraulic
(Dual Cylinder Override The G-Series valve interface
Configuration) Cylinder meets the dimensional
Module requirements of MSS SP-101
or ISO 5211 defined for each
torque range.
• Compact – The G-Series
design optimizes the center of
gravity location, is signifi-
tion features prevent water of overrides, accessories and cantly lighter, and requires
ingress, allowing G-Series other modules. For instance, a less space than other actua-
actuators to meet IP 66 and G-Series actuator may be eas- tors of equal or lesser torque
IP 67M specifications and ily altered from a single-acting output.
severe high pressure water to double-acting power cylin- • Operating Ranges – G-Series
deluge test. der configuration, and/or a double-acting actuators pro-
• Safety – The G-Series facili- hydraulic manual override may duce guaranteed minimum
tates safe installation and be added after the actuator torque outputs up to
removal of the spring module. has been installed. 6,000,000 lb-in. (678,000
It incorporates Bettis’ Tension- • True Modular Design – The Nm). The spring-return units
Lok™ (patent pending) which G-Series versatility is punctu- produce spring torques in
allows for the removal of the ated by field serviceable mod- excess of 3,000,000 lb-in.
spring module in a manner that ules. The available modules (339,000 Nm).
eliminates accidental release include the drive, power, spring G-Series actuators are suit-
of the spring force. Each mod- and override. These modules able for continuous operation
ule is tagged with detailed are removable, serviceable and at pneumatic pressures rang-
product information, minimiz- interchangeable without remov- ing from 40 to 200 PSIG (3 to
ing the potential for incorrect ing the actuator from the valve. 14 BAR), hydraulic pressures
installation, operation, or mis- This procedure does not require up to 5000 PSIG (345 BAR).
application of a reconfigured special tools or disassembly of Standard temperature range is
actuator. any module. This unique feature -20°F to +200°F (-29°C to
• Versatility – The ease of inter- reduces required plant shut- +93°C). Optional temperature
changing the power and down time for service. Modules ranges, as defined in item 37
spring modules allows quick may be replaced as an assem- of the Specification page,
reversal of the “fail-safe” mode, bly or serviced at your mainte- extend the range to -50°F or to
while providing for the addition nance facility. +350°F (-46°C or to +177° C).

3
 Design and Construction
Features 14 Pressure Port 3 Acculine™ 7 Yoke Pin
1 Tension-Lok™ Bettis’ Tension-Lok Shaft Drive Thrust Bar
positively locks in place the spring
module while under load. This 11 Breather 4 NAMUR 2 Power-Swivl™
mechanism prevents spring mod-
ule detachment from the drive
module prior to depressurization,
extension of the spring to a safe
condition, and unseating the Ten-
sion-Lok mechanism.

2 Powr-Swivl™. The PowrSwivl

connects the piston rod and the
guide block, compensating for
side load deflection, thus reduc-
ing wear on the rod, bearings and
seals.
3 Acculine™ Shaft Drive. The Bettis
Acculine Shaft Drive assures a
positive yoke seal, maintains
accurate alignment, and elimi-
nates accessory shaft side loads.
The Acculine Shaft Drive prevents
accidental disengagement of criti-
cal signal devices or controls,
provides visual indication, and
helps maintain the integrity of 15 Bi-directional Travel Stops
hazardous area classified ACTUATOR
HOUSING
devices.
4 NAMUR. The G-Series actuator is 13 Vent-Checks
compatible with a wide range of
control and signal generating YOKE
5 Replaceable Bearings
HOUSING
devices. The NAMUR mounting VENT/CHECK
VALVE 12 MSS and ISO Actu
configuration allows standardiza- VENT/CHECK
tor/ Valve Interface
tion of mounting hardware for
shaft driven accessories.
5 Replaceable Bearings. Replace-
able bearings protect sliding and MSS & ISO
CENTERING RING
(OPTIONAL)
rotating components, and are suit-
able for either dry or lubricated
working conditions. These com- 7 Yoke Pin Thrust Bar. The yoke site the power module, on both
ponents are protected by low fric- pin axial movement is prevented spring-return and double-acting
tion, permanently lubricated by a non-metallic thrust bar actuators, positively separating
bearings which reduce friction transferring axial loads directly power and override fluids. The
losses, thereby improving effi- to the drive module case. manual pump module is inter-
ciency and extending actuator changeable between double-
life. 8 Optional Internal Hydraulic acting and spring-return models.
Override. The internally mounted
6 Guide Block Thrust Bushing. hydraulic override cylinder mod-
Optional features include speed
The Guide Block Thrust Bushing controls, by-pass for high speed
ule for spring-return actuators,
aligns the guide block within the operation, special trims, and
does not increase the overall
yoke arms to enhance the Powr- auto disengage by pilot signal or
length of the actuator. This pre-
Swivl function. power gas.
tested module is mounted oppo-

4
 1 Tension-Lok™
equalization to atmospheric condi-
10 Lifting Eyes tions during operation. The
LOCKED UN-LOCKED breather seals out the environ-
ment, meeting IP67M and accep-
tance criteria for severe high
pressure water deluge test.
12 MSS and ISO Actuator/ Valve
Interface. The G-Series
actuator/valve interface may be
provided with an optional center-
ing ring, assuring accurate align-
ment of the output drive and valve
stem. A female drive, with full
length keyed connection, allows
for mounting the actuator to the
valve in a variety of orientations,
when specified.
13 Vent-Checks. G-Series actuators
incorporate two individual drive
module vent-checks that release
overpressure and seal to prevent
dust, corrosive atmospheres and
9 8 Optional Internal water ingress. The lower vent pas-
Spring Hydraulic Override sage isolates valve stem leakage
Module
6 Guide Block and provides a means to attach
Thrust Bushing fugitive emissions monitoring
REACTION BAR GUIDE BLOCK
devices.
14 Pressure Port. The inboard pres-
sure port location minimizes expo-
sure of supply tubing, thus
ua- reducing the opportunity for
e
mechanical damage on spring-
return units. Pneumatic units fea-
ture NPT ports while hydraulic
units have SAE ports. Consult
factory for options.
POWR - SWIVL(S)™
15 Bi-directional Travel Stops . The
bi-directional travel stops are an
9 Spring Module The springs in 10 Lifting Eyes. G-Series actuators integral part of the actuator allow-
the G-Series actuators are are equipped with integral lifting ing 80° to 100° total travel adjust-
guided by self-lubricating align- eyes for safe handling of the ment. Cylinder mounted extended
ment bearings. The spring mod- actuator during shipping, instal- travel stops are optional.
ule is fully enclosed, and lation or removal. Eight lifting
incorporates the Tension-Lok eyes allow for safely lifting the
+5 –5
mechanism, preventing potential actuator in all three major
injury to operating personnel or planes.
damage to equipment. Corro-
sion resistant coatings and seal
11 Breather. G-Series actuators
incorporate a 316 stainless steel, 100
welding protect the spring mod- 90
normally closed cylinder
ule components from the harsh- 80
breather that allows pressure
est of environments.
–5

+5

5
Typical Specifications

5. The pneumatic power module orientations, as specified.

The following information is recom-
shall be constructed with dual 13. The actuator shall be service
mended as a guide to develop a
internal tie bars of high rated based upon load and
comprehensive, performance ori-
strength alloy steel protected application parameters,
ented pneumatic and hydraulic
by corrosion and wear resis- auditable to accelerated
actuator and control specification.
tant coatings. Power modules wearage test data.
Bettis’ G-Series actuators meet or
shall be constructed to allow 14. Integral lifting eyes shall be
exceed all requirements outlined
pressure testing independent provided to facilitate safe
below.
of the drive module. shipping, handling, installa-
6. The reaction bar shall be tion, and removal of the actu-
Purpose sized to minimize lateral ator. Eight lifting eyes,
To define a pneumatically or deflection, be corrosion and suitable for safely lifting the
hydraulically powered actuator wear protected by a chemi- actuator in all three major
suitable for the operation of ball, cal bath surface conversion planes, shall be sufficiently
butterfly, or plug valves, louvers, process applied in accor- sized and located to accept
dampers, and other 90° rotating dance with Bettis’ ESC 20 appropriately rated lifting
mechanisms. specification, and shall devices.
1. The actuator shall be com- exhibit a minimum surface 15. All external bolting shall be
petitively priced, reliable, hardness of 60 Rc. installed in blind tapped
scheduled maintenance 7. The actuator shall be pro- holes to protect the threads
free, fully resistant to envi- duced, service rated and and positively prevent water
ronmental, power gas, and auditable to a written Quality ingress as defined by the
load conditions. Assurance Program comply- requirements of IP 66 and
2. The actuator shall be ing with ISO 9001, 10CFR50 IP 67M. Sheet or fibrous gas-
designed to facilitate ease of Appendix B, CSA Z-299, and kets shall not be used for
installation and serviceability. when specified, DIN 50049 pressure or environmental
The actuator shall incorporate 3.1.b. seals.
a true modular design to sim- 8. All actuators and modules 16. The NAMUR mounting con-
plify field service, inter- shall meet acceptance criteria figuration shall be incorpo-
changeability of the power defined by Bettis’ ES-6 test rated for the attachment of all
and spring modules, and the specification latest revision or shaft driven accessories. The
addition of manual overrides equivalent prior to shipment. attachment configuration
and accessories. Each pri- 9. The actuator shall be fully shall be identical for all actu-
mary actuator module shall qualified for the purposes ator models and shall pro-
be permanently identified intended by passing all vide visual position
and documented to allow aspects of select industry indication.
accurate identification of performance and design test 17. Accessory drive shaft shall
components and application criteria. be bearing centered, with
criteria. 10. The actuator shall exhibit respect to the mounting
3. The actuator shall meet all excellent corrosion resistance pattern and isolated from
applicable design codes, confirmed by Salt Spray Test- any axial or radial yoke
safety restrictions, and appli- ing per ASTM B117. movements.
cation practices including 11. The valve drive interface 18. All shaft driven control and
SI 1029 regulations and shall meet the applicable signal devices shall be pro-
IP 67M type testing. requirements of MSS SP-101 tected from mechanical dam-
4. The power and spring mod- or ISO 5211 Standards. A age by a bearing centered
ules shall be rigidly attached centering ring shall be pro- shaft drive meeting NAMUR
by external bolting to the vided to assure geometrically dimensional specifications.
drive module and accurately accurate valve/actuator Device attachment shall be
aligned by a piloted interface. alignment, when specified. identical and interchange-
The attachment shall not 12. The actuator shall be pro- able between all models.
require special tools, disas- vided with a full length keyed 19. The spring preload shall apply
sembly, or disturbance of female drive connection suit- a compression force to posi-
seals of any module. able for mounting in multiple tively retain the spring and

6
 drive module interface under without water ingress. to identify proper connection
all operating conditions. 26. The piston rod to guide block of control components.
20. Safe spring module installa- connection shall compensate 34. Bi-directional travel stops
tion/removal shall be inherent for angular and lateral deflec- shall be included as an inte-
within the spring attachment tion caused by side loads. gral part of the actuator
design and shall not require 27. The piston rod shall be allowing 80° to100° total
special tools. The locking detachable from the drive travel adjustment.
mechanism shall be self- module without the need of 35. For spring-return models,
engaging and highly visible special tools or module dis- the optional, single-acting
during assembly, assuring assembly. hydraulic override cylinder
that the lock position is 28. Replaceable bearings shall shall be installed inside the
attained. The mechanism exhibit documented, spring module and shall not
shall positively disallow extended wear capabilities increase the length of the
spring module detachment and shall be suitable for dry actuator. The cylinder shall
while in a loaded condition, or lubricated working condi- be pre-assembled and
preventing sudden or violent tions. Sliding and rotating fer- tested prior to installation.
release of the spring module. rous metal surfaces shall be 36. The optional hydraulic man-
21. The spring module shall be protected by suitable bear- ual override module shall
fully enclosed to eliminate ings to control wear. incorporate a positive dis-
personnel hazards, o-ring 29. Durable wear and corrosion placement piston pump,
sealed and welded to protect resistant ferrous metal con- directional control valve, fluid
all components from harsh version coatings shall aid reservoir, level indicator, and
environmental conditions. extended wearage resistance pressure relief. Optional
22. The spring and spring and rated torque output as enhancements shall include
retainer shall be self-cen- published when completely bi-directional speed controls,
tered and bearing guided void of supplemental petro- by-pass for high speed oper-
within the spring module. The leum or synthetic grease or ation, special trims, and auto
spring retainer shall transfer oil. Metallic coating of pres- disengage by pilot signal or
axial tension and limit buck- sure containing and load power gas pressure.
ling, minimizing metal-to- bearing surfaces which can 37. The construction of the actu-
metal contact between the be scratched, cracked, or ator shall be suitable for con-
spring and barrel. peeled allowing ferrous metal tinuous exposure to ambient
23. All module interfaces shall or sharp seal cutting edges to temperatures of -20°F to
include a precision machine be exposed are prohibited. +200°F (-29°C to +93°C).
pilot to ensure accurate 30. All contact surfaces of the Optional low temperature trim
alignment. guide block assembly shall is available, allowing continu-
24. The spring-return actuator incorporate replaceable bear- ous operation at -50°F to
shall utilize an inherently ings and a rigid rotating pin +180°F (-46°C to +82°C) for
guided tension rod to energize torque transfer mechanism, pneumatic units and -50°F to
the compression spring elimi- reducing wear caused by pin +200°F (-46°C to +93°C) for
nating the need for tie bars. deflection. hydraulic units. Optional high
25. Each actuator shall be fitted 31. The yoke pin shall rotate in a temperature trim is suitable
with two (2) 316 stainless self-lubricating bearing to for continuous exposure to
steel, normally closed vent- eliminate sliding friction in the ambient temperatures
checks to protect the drive yoke slots and shall be between 0°F to +350°F (-18°C
module from overpressure. retained by stationary non- to +177°C).
The single-acting actuator metallic thrust bars to reduce 38. Standard valve position stops
power module shall incorpo- wear and extend the service shall provide +/-5° adjust-
rate a 316 stainless steel bi- life of the actuator. ment and be capable of
directional breather/vent. 32. The manufacturer shall pro- stalling the actuator at the
Each actuator shall be appro- vide a five-year materials and maximum torque output. Full
priately sealed in a manner workmanship warranty. range extended travel stops
meeting IP 66, or IP 67M, and 33. All actuator pressure ports shall be provided, when
high pressure deluge test shall be appropriately marked specified. 7
Headquarters Optional Overrides
P.O. Box 508
Bettis offers several overrides for G-Series model, they include:
Waller, TX 77484
U.S.A. Jackscrew – manual override for G-1, G-2, and G3 models
Tel: 281/463-5100 with or without handwheel.
Fax: 281/463-5103 G-Ride – gear override available on G-4 and G-5 models.
E-mail: All overrides have a variety of options available including
marketing.bettis@bettis.com proximity switches and lock out features
Website: www.bettis.com

Bettis UK Ltd.
Brunel Way Bettisystems
Fareham, Hampshire PO15 5SA
Bettis has pre-engineered and documented a series of
England
commonly required control systems. These approved systems
Tel: 0148-988-5333
utilize standard components, reduce lead times, and simplify
Fax: 0148-988-5200
purchasing, installation and start-up. Please consult the factory
Tlx: 47493
for additional information.
Bettis Canada Ltd.
4112-91 A Street
Edmonton, Alberta T6E 5V2
Canada
Tel: 780/450-3600 Bettis Technical Data
Fax: 780/450-1400 Brochure & Website
Bettis Int’l Sales Office: For torque outputs,sizing informa-
Calgary, Canada tion, displacements, weights and
Dubai, U.A.E dimensional drawings on G-Series,
Rheinberg, Germany see Bettis’ Technical Data Brochure
New Bombay, India or visit our website at
Singapore www.bettis.com.

Bettis France:
30/36 Allee du Plateau
93250 Villemomble
France
Tel: 331-48-122610
Fax: 331-48-122619

Important: Due to Bettis’ continuing commitment to engineered product

advancement, data presented herein is subject to change.

Bettis Bulletin # 35.00-1

Rev: 5/01

© 2001 Emerson. All rights reserved.

2.5M/5/01