TABLE OF CONTENTS
- SCOPE
- REFERENCES
- DEFINITIONS
- GENERAL
- Data
- Basic Requirements
- VALVE BODY
- Globe Valves
- Three way Control Valves
- Angle Valve
- Pinch / Saunders Valve
- Rotary Style
- Self Actuated Regulators
- End Connections
- VALVE PARTS
- Trim
- Stem
- Packing
- Gaskets
- Guide Bushings
- Bonnet
- Bolting
- FLOW CHARACTERISTICS
- SEAT LEAKAGE
- General
- FIRE SAFE VALVES
10. GENERAL SIZING REQUIREMENT
10.1 General
10.2 Noise
10.3 Vibration and Erosion Limits
10.4 Cavitation, Choked Flow and Flashing
11. ACTUATORS
11.1 General
12. VALVE ACCESSORIES
12.1 General
12.2 Positioners
12.3 Valve Position Switches / Limit Switches
12.4 Solenoid Valves
12.5 Booster Relays / Quick Exhaust Valves
12.6 Lock Up Valve
12.7 Handwheel
12.8 Travel Stop
12.9 Air Filter Regulator
13. SPECIAL REQUIREMENTS
13.1 Data Sheets
13.2 Identification
13.3 Metal Tag
13.4 Data Plate
13.5 Casting or Stamping
13.6 Information Provided by Vendor
13.7 Shipping
13.8 Inspection and Testing
1. Scope
This specification establishes minimum requirements for design, sizing and selection of control
valves having broad application capability in hydrocarbon processing industry and other SABIC
industries.
Basic data and specifications shall be provided through instrument data sheets and general
specifications, where ever necessary. While these specifications cover specific design criteria,
the detailed design features shall be proposed by the vendor for each application.
2. References
Reference is made in this standard to the following documents. The latest issues, amendments,
and supplements to these documents shall apply unless otherwise indicated.
SABIC Engineering Standards (SES)
D02-D02 Engineering Tools and Data Structure
I01-G01 Process Design and Engineering Standard
P25-G01 Selection of Flanges
R01-E02 Hazardous Area Instrumentation Protection – Explosion Proof
R01-E05 Fire Safe Instrumentation
R07-T01 Inspection and Testing of Control and On-Off Valves
X05-E02 Field Device Cabling to Junction Boxes
Z01-G04 Measurement Units for Use in SABIC Projects
Process Industry Practices (PIP)
PCCCV001
Control Valves Selection Criteria
PCECV001 Guidelines for Application of Control Valves
Institute of Electrical and Electronics Engineers (IEEE)
Std1 Recommended Practice – General Principles for Temperature Limits
International Society for Automation (ISA)
20
Specification Forms for Process Measurement and Control Instruments, Primary
elements, and Control Valves
75.01.01 Flow Equations for Sizing Control Valves
75.08.01 Face to Face Dimensions for Flanged Globe-Style Control Valves Bodies
75.08.02 Face to Face Dimensions for Flangeless Control Valves Bodies
75.05.01 Control Valve Terminology
75.17 Control Valve Aerodynamic Noise Prediction
75.19.01 Hydrostatic Testing of Control Valves
RP75.23 Consideration for Evaluating Control Valve Cavitation
American Society of Mechanical Engineers (ASME)
B1.20.1 Pipe Threads, General purpose (inch)
B16.25 Butt Welding Ends
B16.34 Valves- Flanged, Threaded, and Welding End
B16.47 Large Diameter Steel Flanges, NPS 26 in through NPS 60 in
B16.5 Pipe Flanges and Flanged Fittings, NPS ½ in thru NPS 24 in
B31.1 Power Piping
B31.3 Process Piping
BPVC Boiler and Pressure Vessel Code – Section I
Fluid Control Institute (FCI)
70-2 Control Valve Seat Leakage
International Standards Organization (ISO))
15848
Industrial Valves- Measurement, Test and Qualification Procedures for Fugitive
Emissions
British Standards Organization (BS)
6364 Specifications for Valves for Cryogenic Services
National Association of Corrosion Engineers (NACE)
0103 Standard Material Requirements – Materials Resistant to Sulfide Stress
Cracking in Corrosive Petroleum Refining Environments
0175/ISO15156 Petroleum and Natural Gas Industries – Materials for Use in H2S Containing
Environment in Oil and Gas Production
Manufacturers Standardization Society (MSS)
25
Standard Marking System for Valves, Fittings, Flanges and Unions
American Petroleum Institute (API)
607
Testing Requirements for Fire Safe Valves
609
Butterfly Valves: Double Flanged, Lug- and Wafer Type
941
Steel for Hydrogen Service at Elevated Temperature and Pressure
ASTM International (ASTM)
A193/A193M-11 Standard Specification for Alloy-Steel and Stainless Steel Bolting for High
Temperature or High Pressure Service and Other Special Purpose
Application
A194/A194M-10a Standard Specification for Carbon and Alloy Steel Nuts for Bolts for High
Pressure or High Temperature Service, or Both
A320/A320M-11 Standard Specification for Alloy-Steel and Stainless Steel Bolting for Low
Temperature Service
3. Definitions
Instrument Data Sheet. Instrument data sheets are documents that contain physical and
functional parameters for each instrument. These parameters include but not limited to process
data, operating conditions, process connections, material of construction, signal ranges, and
manufacturer‟s model number and types.
Per ISA 20, instrument data sheets are intended to assist the specification writer to present the
basic information. In this sense they are „short- form specifications‟ or „check sheets‟ and can
not include all necessary engineering data or definitions of application requirements.
Instrument Specifications. Instrument specifications are the detailed requirements prepared
based on instrument data sheet
4. General
4.1 Data
4.1.1 An instrument data sheet shall be provided for each control valve.
4.1.2 As a minimum, templates for instrument data sheet shall be as per SES-D02-D02 Electronic
Data and Document Management System (EDDMS) seed files.
4.2 Basic Requirements
4.2.1 Valve design shall be based on process application, design pressure and temperature
requirements and economic considerations.
4.2.2 Refer to PIP PCCCV001 for recommended valve body types.
4.2.3 The materials selection shall be as per piping specifications and the process conditions.
4.2.4 For critical services valve or in applications where uncertainty about material selection
exists, valve body and trim material selection should be made in consultation with the
material specialist and valve vendor..
4.2.5 Reference to PIP PCECV001 shall be made when clear guidelines are not available in this
standard.
4.2.6 The terminology and definitions shall be per ISA 75.05.01.
4.2.7 Measurement units shall be as described in SES-Z01-G04.
4.2.8 Control valve body sizes less than 1 inch can only be used for special applications with
SABIC approval. Smaller body sizes can be used for pressure regulators in ¾ inch or
smaller line sizes. Body sizes of 1¼, 2½, 3½, 5 and 7 inch shall not be used.
4.2.9 Minimum pressure rating for control valve body/flange shall conform to pipe class
specifications. Refer to PIP PCECV001 “minimum flange rating” for details.
4.2.10 For flanged valves, body rating shall not be less than the flange rating.
4.2.11 Valve face to face dimensions, bolt drilling, etc., shall conform to ISA 75.08.01 and ISA
75.08.02.
4.2.12 Flushing connections shall be provided in accordance with the instrument data sheets.
Bottom flanges shall not be tapped unless flushing connections are specified.
4.2.13 Use of Asbestos in any form is prohibited.
4.2.14 All electrical accessories shall comply with SES-R01-E02 for hazardous area classification
requirements specified in the instrument data sheet.
4.2.15 Control valves shall be supplied as a completely piped and tested unit, ready to be mounted
on piping. Procedure and additional hardware required for disassembly of the valves
internals for hydro-testing or welding the valve shall be provided by the vendor.
4.2.16 All valves including internal components, actuator, instruments and accessories shall be
provided as new and unused. Remanufactured or refurbished products are not acceptable
4.2.17 Bar stock body shall be used for high pressure application with SABIC approval.
4.2.18 Valves operating at elevated temperatures shall be equipped with temperature
compensation to allow for stem expansion and contraction without affecting valve seating.
4.2.19 Anti-cavitation trim shall be used for applications where cavitation or flashing is likely to
occur, refer to cavitation, choked flow and flashing section.
5. Valve Body
5.1 Globe Valves
5.1.1 The pressure-temperature rating, dimensions, tolerances, materials, non-destructive
examination requirements, testing and marking for casting, forged, and fabricated steel
flanged, threaded, and welding end valves shall comply with ASME B16.34 with the
following exceptions:
a. Hydrostatic testing shall be performed on pressure boundary parts and components as
per ISA S75.19.01.
b. On an optional basis valves can be supplied to the following codes and standards as
specified for a specific need.
c. ASME B16.34 Special Class Pressure and Temperature Ratings
d. ASME B31.1 and B31.3 for welding fabricated equipment
e. ASME BPVC Section I.
5.1.2 Flow direction through the valve shall be considered „Flow to Open‟. However, when it is
necessary to select the flow direction as „Flow to Close‟ due to process requirement, it shall
be considered with SABIC approval
5.1.3 Unbalanced valves shall be stem, post or port guided and shall provide adequate guiding for
the specified service conditions. Pressure balanced valves shall be cage guided.
5.1.4 Unbalanced cage guided valves shall be used in applications with some performance
benefits. Cage guided valves shall not be used for coke forming and fouling services.
5.1.5 Double port valves shall not be used without SABIC approval.
5.1.6 Split body globe valves shall not be used.
5.1.7 Fabricated bodies shall be used when either cavitation trims or low noise trims are too large
to be installed in standard control valve bodies. These valves shall be fabricated to ASME
B31.3 requirements.
5.1.8 Pressure seal bonnet designs that use pressure assist to seal the bonnet as opposed to bolt
loading are not acceptable.
5.1.9 Compressible fluids requiring noise attenuation shall utilize a flow up configuration which
minimizes trim induced noise.
5.1.10 Plug stem connections shall be designed to ensure positive connection to avoid separation
during operation.
5.2 Three way Control Valves
Usage of three way control valve shall require SABIC approval.
5.3 Angle Valve
5.3.1 Angle valve selected for severe flashing, cavitation and slurry services shall have full venturi
throat or sleeve made of hardened material to prevent erosion.
5.3.2 Angle valve shall conform to the specifications for globe valves with heavy duty top guided
stem and long sleeve exit throat.
5.4 Pinch / Saunders Valve
5.4.1 Pinch type valves can be used in corrosive and plugging services and in streams with
entrained solids.
5.4.2 The flexible liners shall have process compatibility and enough strength for the modulating
service application.
5.4.3 Pinch valves are zero emission type valves; however consideration for diaphragm/liner
failure shall be given prior to their selection.
5.5 Rotary Style
5.5.1 Rotary style control valves include, butterfly, eccentric disc, ball, segmented ball,and plug
valves.
5.5.2 Rotary style valves have high Cv and higher pressure recovery factor compared to the same
size sliding stem globe valves.
5.5.3 Rotary style valve shaft shall be designed for pressure drop equal to the maximum
upstream design pressure. The shaft shall be designed with blow out prevention disk to
retain the shaft in the event of shaft failure.
5.5.4 Rotary valves shall have shaft keyways or splined shafts that allow the action of the valve
actuator to be changed.
5.5.5 For low fugitive emission services, rotary valves are preferred over sliding stem valves
because of the inherent higher reliability of the shaft sealing.
5.5.6 Rotary Plug, Ball and V Notch Valves
a. The seat ring and seat joint area of the segmented ball or plug valves shall be designed
for continuous throttling service. Ball valve stem seals shall be resistant to vibration.
b. Characterized ball type, with downstream seal or upstream and downstream seals can
be considered for slurries and corrosive service. The use of reduced ball trim is allowed.
5.5.7 Butterfly Valves
a. The minimum size for butterfly valve shall be 3 inch.
b. Butterfly valves shall meet the requirement of API 609, for shaft retention thrust collar or
blowout preventer.
c. Body configurations can be flangeless solid ring wafer for installation between pipe
flanges, single flange or lug pattern, or double flange spool type. The wafer type valves
shall have centering lugs or other means for positive body and flange alignment. Refer to
end connections sections for usage of flangeless valves.
d. Swing through type butterfly valve shall only be used for low pressure drop service.
e. High performance butterfly control valve having eccentric and cammed motion, double
offset shaft and disk are recommended over standard butterfly valves. Eccentric disc
butterfly valve shall not be used for throttling service near the seat.
f. Because of large pressure recovery coefficient, butterfly control valves shall not be used in
applications where cavitation is likely to be present.
g. Consideration shall be given for clearance requirement for the disc to eliminate any
interference with lined or heavy wall piping.
h. Preferred installation orientation of the body is with the shaft in horizontal plane. Where
vertical plane orientation is specified, the vendor shall provide a design, which has a
positive means of maintaining disk alignment in the valve. Vertical shaft orientation shall
be avoided for valve operation and maintenance performance.
i. The valve body shall be provided with a disk over travel stop to prevent excessive disk
rotation and seat seal damage.
j. The disk shall be positively attached to the shaft. At the specified shut off differential
pressure the shear safety factor shall be 150 percent.
k. . The shaft and disk combination shall be designed to withstand the maximum torque.
l. The Vendor shall review butterfly valve applications on liquid service and state the minimum
recommended closing time to avoid possible hydraulic shock damage.
m. Vendor shall specify the limitations on the differential pressure for which the disc and
shaft operation can be guaranteed. Vendor is responsible for checking torque conditions
for the differential pressure specified in the service to ensure actuator size is adequate
for successful operation in the application.
5.6 Self Actuated Regulators
5.6.1 Self-actuated regulators shall have the same general requirements as control valves.
Failure action of the regulators shall be considered in the design.
5.6.2 Self-actuated regulators shall be used for non critical services where frequent set point
adjustments are not required and a variation of ± 10 percent of the set pressure is
acceptable (e.g., fuel gas, potable water utility stations, etc).
5.6.3 Pilot-operated regulator shall be used where accurate control is required. Yoke mounted
pilot shall be used with SABIC approval. Pilot operated regulator shall only be used in clean
services.
5.6.4 Self actuated regulators shall not be used in corrosive, toxic, cavitation, flashing, high noise
and erosive services.
5.6.5 Nitrogen blanketing for storage tanks shall be implemented with appropriate blanketing
regulators with pressure and vacuum relief. Such application shall be detailed in the
application specific instrument data sheets.
5.6.6 Actuator and pilot assembly of self actuated regulator shall be capable of withstanding 150
percent of the maximum upstream design pressure, unless other means of pressure relief is
provided.
5.6.7 Venting regulators in hydrocarbon service shall have the vent piping routed to a safe
location.
5.6.8 Cast iron shall not be used as a control valve body material.
5.6.9 Materials like plastic, aluminum and brass shall not be used as valve body or any process
wetted parts.
5.7 End Connections
5.7.1 Flanged end connections are preferred for all valves. Flange type, rating, and finish shall be
as specified on the instrument data sheets. For flanged valves, body rating shall not be less
than the flange rating.
5.7.2 Welded end valves are recommended for high temperature and pressure service, where
leak proof connections are required, and shall require SABIC approval. Butt welded end
valves shall be in accordance with ASME B16.25. The end to end dimension of the butt
weld end valves connections shall permit field welding without seat distortion or damage to
the valve soft seats. Valve trim should be removed prior to any welding or post weld heat
treat to prevent damage to components.
5.7.3 Usage of threaded valve shall require SABIC approval. Threaded end valves shall be limited
to 1 inch size or smaller and shall be furnished with internal tapered threads to ASME
B1.20.1. Threaded valves shall have minimum class 600 body rating.
5.7.4 The flanges for valve sizes above 24 inch shall be per ASME B16.47, series B.
5.7.5 Flangeless valve shall be used as per PIP PCCCV001 criteria.
5.7.6 The ASME B16.34 shall be followed for casting, forged, fabricated steel, threaded and butt
weld type end for the valves.
5.7.7 Flanges shall be integral for all sizes of globe valves as per ASME B16.5. Slip-on and
separable flanges shall not be used without SABIC approval.
5.7.8 Flange contact suface finish shall be as per SES P25-G01.
5.7.9 Valve flange end shall not be flat face type.
5.7.10 Bonnet and end flange material of construction, finish, size, and ASME class rating shall be
stamped on the valve body as specified in data sheet.
6. Valve Parts
6.1 Trim
6.1.1 Manufacturer‟s standard valve trim for the specified body style shall be given the first
consideration.
6.1.2 Trim shall be designed to have equal pressurization around the plug to minimize vibration
and potential for binding.
6.1.3 Globe valve trim shall be of quick change design for ease of maintenance. All valves shall
have removable seat rings and solid plugs. Valves shall have inner trim removable through
the top of the valve body.
6.1.4 Threaded seat rings are allowed only for 3 inch and smaller globe valve sizes and with
SABIC approval.
6.1.5 Trim configurations such as pressure balanced, anti-cavitation, and low-noise shall be
available in the basic body style and sizes.
6.1.6 Trim parts (e.g., plug, seat, bush, etc.) shall be machined from single piece bar stock or
casting.
6.1.7 Control valve body with reduced trim shall be considered for applications with pressure drop
in excess of 5170 kPa, gas outlet velocities in excess of 0.3 Mach, high noise exceeding 85
dBA, choked flow, flashing exceeding 5 percent weight of the liquid, erosive fluids and in
applications where future capacity increase is anticipated.
6.1.8 Guiding shall be either cage, post, or port guided as a function of required stability, service
conditions, and capacity.
6.1.9 Valve trim that use pressure staging to protect the internal parts from damage should be
designed to insure adequate pressure recovery between stages.
6.1.10 Trim component selection shall be guided by the process fluid and service conditions. As a
minimum, standard trim components shall be 316 SS.
6.1.11 Higher alloy grades 440 C and 17-4 PH should be used for severe service applications.
Some examples of severe service applications are:
a. When pressure of steam or condensate from boiler drops below 6.90 barg (100 psig).
b. Where more than 3 percent of the inlet fluid gets vaporized in the valve having pressure
drop below 10.34 barg (150 psig).
c. When pressure reduction is more than 17.24 barg (250 psig) for any application.
6.1.12 Where Stellite hard facing is specified, full contour plug and full bore seat ring stellite shall
be provided. For severe service applications, this can also include the lower guide area on
the stem.
6.1.13 Sea water control valve trim should be Monel
6.1.14 Specialty trim materials facings, e.g. Tungsten Carbide overlay, shall be considered for high
temperature and high differential pressure steam and BFW applications.
6.1.15 Where hard facing or overlay is required, all surfaces shall be covered with minimum 1.3
mm and maximum 2 mm thickness of the specified hardened material.
6.1.16 Trim of the valves used for cavitation or flashing service shall have hardened trim material.
The hardness should be at least 38 Rc – Rockwell hardness.
6.1.17 PTFE Coated plug valves can be used in corrosive chemical services.
6.1.18 In general, austenitic stainless steel disks and shafts shall be used with all lined, as well as
carbon or stainless steel standard valve bodies. If required, vendor can offer alternates such
as 17-4 PH or Nitronic shafts for high performance valves to meet service conditions. Other
alloy valves shall use matching alloy disks, shafts, and pins, or suitable alternates to meet
the service conditions. Chrome or other disk edge hard facing shall be used with metal disc
and seats.
6.2 Stem
6.2.1 Control valve stems shall be heavy duty and preferably capable of handling at least one size
larger actuator than normally furnished for a given valve size.
6.2.2 Stem and stuffing box finish shall be a maximum of 8 micro-inch AARH and suitable for both
PTFE and graphite stem packing.
6.2.3 Protection cover assembly shall be provided to the sliding stem of control valves to protect
packing and stem from contamination due to sand and dust.
6.3 Packing
6.3.1 For vacuum services or applications where the valve can be subjected to vacuum during
steam out, the packing shall be designed for the vacuum service.
6.3.2 Use of bellow seals shall be considered only for toxic or cryogenic services and their design
and application shall be approved by SABIC.
6.3.3 Bellows shall have, at operating pressure and temperature, capability of minimum 10,000
cycles at full stroke, 100,000 cycles at half stroke, and 1,000,000 cycles at quarter stroke. A
full set of secondary stem seal packing shall be provided as a backup seal.
6.3.4 The bellow seal should have feature of anti-rotation to prevent twisting. It should sustain 1.3
times maximum allowable pressure and should not remain in tension or compression
position at neutral position.
6.3.5 Packing shall limit fugitive emissions in accordance with PIP PCCCV001 requirements.
6.3.6 PTFE packing is preferred for service temperatures below 232 deg C (450 deg F). PTFE
shall not be used for temperature below -18 deg C for standard bonnet and below – 45 deg
C for extended bonnets
6.3.7 Graphite ultra-low friction (ULF)packing is preferred for service temperatures above 232 deg
C (450 deg F) to minimize packing friction. Graphite ULF packing shall be used for steam
and condensate service or temperature exceeding 232 deg C
6.3.8 Live loaded packing is preferred for all control applications.
6.3.9 Vendor recommended alternative packing materials shall be used to meet operating
temperature and process requirements with SABIC approval.
6.3.10 As far as possible, packing requiring lubrication shall not be used. If stick grease lubrication
of packing is required, then valve shall be furnished with lubricator and isolating valve.
6.3.11 Bellows shall be 316L or other alloys as specified in the data sheet.
6.3.12 Packing glands shall be austenitic or duplex stainless steel.
6.4 Gaskets
6.4.1 All body, bonnet and seat ring gaskets are to be fully inserted within the parts cavities and
designed such that correct gasket compression for both the bonnet and seat ring gaskets is
obtained.
6.4.2 Gasket material shall be compatible with the process fluid
6.4.3 Metal and other non standard gasket configurations shall require SABIC approval.
6.4.4 Gasket construction shall be SS 316 spiral wound using high density wound filler of PTFE,
or graphite to suit body material and service. For valve bodies other than carbon steel or
austenitic stainless steel, suitable alloy gasket rings shall be provided by the vendor.
6.4.5 Sheet stock or flat gaskets of, PTFE or graphite can be used as alternates where valve
design and service conditions permit. Gasket designs using these materials having metal
insert shall use 316L stainless steel as the insert unless the service conditions dictate the
use of other alloys.
6.5 Guide Bushings
6.5.1 Stem guide bushings shall be provided for top and bottom stem guiding and shall be
interchangeable. Bushings shall meet the service conditions stated in the instrument data
sheet.
6.5.2 For rotary valves, stem bearing should be designed to prevent guide bushing from rotating
in the valve body. Galling of the stem and bearing material shall be prevented by suitable
bearing material selection.
6.5.3 The following guide bushing materials shall be selected, provided all process service
conditions are met:
a. Glass Filled-PTFE lined stainless steel or PEEK
b. Stainless steel or solid stellite
c. Bushings of other alloys which shall meet the needs of alloy bodies of the specified
service conditions.
6.6 Bonnet
6.6.1 Bonnets shall be available in standard, plain, and bellows extension configurations. Cold
box or special extensions shall be optional alternatives.
6.6.2 Bonnet designs shall have capability to cover the temperature range of -198 deg C to +649
deg C depending upon the process application.
6.6.3 The bonnet shall be of bolted construction. Screwed bonnets are not allowed. The yoke
shall be open type to access the packing gland follower for adjustment.
6.6.4 Packing follower shall be minimum 316 SS, unless 316 SS is not process compatible
6.6.5 The bonnet shall be of the same materials as the body or forged equivalent.
6.6.6 External steel or iron parts on actuator, bonnet and yoke are to be coated with corrosion
resistant protective finishes suitable for outdoor service.
6.7 Bolting
Packing follower flange, packing gland, attachment of actuator and yoke to valve body and any
other required bolting shall be minimum of the following materials:
6.7.1 For carbon Steel and Low Temperature Carbon Steel body: ASTM A193-B7 (studs) and
ASTM A194-2H (nuts) and for low temperature applications ASTM A320 L7 (studs) and
ASTM A194-4 or 7(nuts) shall be used.
6.7.2 For 316 Stainless Steel Body, ASTM A193-B8 CL. II (studs) and ASTM A194-8 (nuts) and
for low temperature applications A320-B8 CL.II (studs) shall be usedFor carbon steel or any
chrome molybdenum body temperature above 400 deg C, ASTM A193-B16 (studs) and
ASTM194-8 (nuts) shall be used.
6.7.3 For exceptional cases, bolting requirement shall be furnished on the valve data sheet.
7. Flow Characteristics
Flow characteristics shall be in accordance PIP PCECV001 criteria.
8. Seat leakage
8.1 General
8.1.1 Control valve seat leakage class shall be determined by the service applications. Seat
leakage classification shall be as outlined in ANSI/FCI 70-2.
8.1.2 Seat leakage shall be ANSI/FCI 70-2 Class IV as a minimum, less than Class IV shall
require SABIC approval.
8.1.3 For control valves that shall provide a tight shutoff (TSO), the valves shall be in accordance
with ANSI/FCI 70-2 Class V minimum. Typical applications include boiler start up, turbine
bypass, compressor recycle and flare let down services.
8.1.4 Leakage class shall be as per vendor‟s standard manufacturing methods. Lapping of plug
and seat or other such methods to meet a leakage class is not acceptable.
8.1.5 Soft seat valves shall not be used in flashing services.
9. Fire Safe Valves
Fire safe valves shall be certified per API 607 test, if specified on the valve data sheet. For fire
proofing of the valve actuator and accessories, SES-R01-E05 shall be followed.
10. General Sizing Requirement
10.1 General
10.1.1 Control valve sizing shall be conducted using accepted standards and recommended
practices such as ISA 75.01.01 or vendor proprietary methodology.
10.1.2 Control valves should be sized for a minimum of three operating conditions: minimum,
normal, and maximum.
10.1.3 Valve opening shall be in accordance with SES I01-G01 requirements.
10.1.4 Rotary control valves operating range shall be in accordance with PIP PCCCV001
requirements.
10.1.5 Ratio of nominal pipe size to body size shall not be greater than 2:1
10.1.6 Control valve body size shall not be greater than the line size.
10.1.7 Vendor shall be responsible for sizing calculations and valve selection for all the process
conditions specified on the instrument data sheet.
10.1.8 Control valve velocity shall be limited to 10.2 m/s (33 ft/sec) for liquids or Mach 0.3 for
steam, vapor or gases. For erosive services maximum velocity shall not exceed 6.2 m/s (20
ft/sec).
10.2 Noise
10.2.1 Noise calculations shall be provided for all applications. Noise calculations shall not include
any adjustments for insulation unless clearly identified.
10.2.2 Control valve noise shall be calculated in accordance with methodology outlined in ISA
75.17 guidelines.
10.2.3 Noise calculations shall include influence of valve trim and valve outlet velocity induced
noise. Total calculated noise shall not exceed 85 dBA for continuous exposure as measured
1 meter downstream and 1 meter away from the surface of the downstream pipe.
10.2.4 Source treatment is the preferred method for reducing valve noise. Examples of source
treatment are noise reducing trim (preferred), in-line diffuser or silencer. Note that in-line
diffusers and silencers are fixed capacity devices and can compromise desired control
characteristics in high turndown applications. Path treatment (insulation) can be used to
reduce noise in cases where source treatments are deemed impractical. Diffusers, baffle
plates and silencers shall require SABIC approval.
10.2.5 Vanes of swing through butterfly valves shall incorporate spoilers, for example fish tail to
reduce aerodynamic flow effects.
10.3 Vibration and Erosion Limits
10.3.1 Control valve selection shall ensure that the fluid kinetic energy is dissipated without
exceeding the maximum vibration levels in the piping system and causing damage to the
body and trim material.
10.3.2 Control valve vibration and trim erosion can be reduced by multi-stage multi-path trim
designs.
10.4 Cavitation, Choked Flow and Flashing
10.4.1 ISA 75.01.01, ISA RP75.23 and the vendors‟ valve cavitation index data shall be used for
determining the severity of cavitation, choked flow or flashing conditions in the control
valves. Vendor shall provide a control valve that addresses cavitation and flashing damage.
10.4.2 The design of the valve in cavitation and flashing services shall be based on ISA 75.01.01
and shall include the following techniques for cavitation and flashing resistant valves:
a. Reduce the pressure in multiple stages
b. Direct flow away from the valve body and pipe walls
c. Break the flow into many small streams
d. Force the flow through multiple turns or tortuous paths
e. The valve outlet should not be smaller than the downstream pipe size.
f. Provide minimum 10 diameter straight run at the outlet of the valve.
g. Provide an expander in the outlet of the valve.
h. Sacrificial downstream piping, special multi stage pressure reduction trims with hardened
alloys are recommended for flashing related issues.
i. For valve controlling feed to a vessel, mounting the valve on the vessel flange can be
considered, eliminating the downstream piping.
10.4.3 Manufacturers shall analyze valve data sheet for cavitation, noise, or other detrimental
factors, using the data on the data sheet as a basis. Undesirable operating conditions shall
be brought to SABIC attention, including noise or cavitation severity levels. Vendor shall
propose possible solutions to these problems within the limits of the type of valve covered
by this standard or indicate that another special valve design is required.
11. Actuators
11.1 General
11.1.1 Actuator shall be in accordance with PIP PCCCV001 criteria.
11.1.2 Control valve actuator shall be pneumatic. Electrical and hydraulic actuators shall be
avoided for throttling service valves and shall be specified only with SABIC approval.
11.1.3 Sliding stem actuators shall be mounted in a vertical position in order to avoid side loading
on the trim and packing.
11.1.4 Sliding stem actuators shall provide anti-rotation design to protect the valve plug from
rotating.
11.1.5 Control valve actuators shall be pneumatic and sized to function effectively at minimum 4.0
barg air supply pressure.
11.1.6 Maximum differential pressure shall be the maximum upstream pressure with the control
valve fully closed and downstream at atmospheric pressure. 1.25 times maximum
differential pressure shall be used in the actuator sizing calculation, in addition to other
factors such as leakage requirement, seat loading, packaging friction, etc.
11.1.7 Local valve position indicator shall be provided for each control valve.
11.1.8 The actuator shall have limits to protect over travel.
11.1.9 For opening, the stopper shall be engaged before plug reaches to its maximum opening
travel limit. The stopper should be designed to withstand against the force transmitted to it.
11.1.10 For closing, the plug should touch the seat before actuator reaches to its maximum closing
travel limit.
11.1.11 All actuators shall have the maximum pressure rating of the assembly clearly and
permanently marked on the actuator. A clear, permanent, and readily visible tag shall be
attached to spring
loaded actuators stating, “DANGER – SPRING UNDER
COMPRESSION,” or equivalent phrase.
11.1.12 The actuator spring shall be fully enclosed in metal housing to protect it from atmospheric
corrosion. Springs, fasteners and all hardware shall be resistant to environmental corrosion
by suitable coating and paint.
11.1.13 Actuators shall be without force multiplying linkages.
11.1.14 Nylon-reinforced neoprene or Buna N rubber shall be used for diaphragm. However, Buna N
shall not be used as diaphragm or seal material if wet hydrocarbon gas is used instead of
instrument air.
11.1.15 Material of springs, internal parts, fasteners, and other hardware used in actuator shall be
resistant to the corrosive environment effect.
11.1.16 For actuators without spring, fail open or fail closed shall be achieved by using volume tank
with all required accessories including check valve. The volume tank shall be designed in
accordance with PIP PCCV001 requirements.
12. Valve Accessories
12.1 General
12.1.1 Tube fittings used for interconnection of actuator, positioner, quick exhaust valves, solenoid
valves, booster relays, or other accessories, shall be 316 SS, twin ferrule compression type
imperial sizes with NPT threads. Tubes shall be seamless 316 SS and tube size shall be
compatible with actuator, positioner, air sets and the other valve accessories.
12.1.2 Actuators and associated accessories shall be assembled, piped, mounted on control valve,
aligned, tested and shipped as a complete unit.
12.1.3 Actuators and accessories shall be appropriate for the atmosphere in which they are
installed. All electrical accessories shall be suitable for the specified hazardous area
classification as per requirements of SES-R01-E02.
12.1.4 Terminal box suitable for the hazardous area classification requirement shall be mounted on
the valve assembly for wiring the limit switches and solenoid valves.
12.1.5 Air exhaust connections shall be oriented to exclude or minimize the entry of water and dirt.
12.1.6 Bug screens shall be installed on all air exhaust ports.
12.1.7 For standardization purpose, valve accessories for each body size and actuator size shall
be interchangeable regardless of material of construction.
12.2 Positioners
12.2.1 All control valves in modulating services shall have high-performance, smart digital
positioners. Positioners shall be supplied with gauges on air inlet and in all air outlets to the
actuator. The signal communication protocol shall be as specified on the control valve data
sheet. Smart positioners shall have capability for digital integration to the control system via
HART or FF, use of another communication protocol shall require SABIC approval.
12.2.2 Separate electro-pneumatic convertor and a pneumatic valve positioner shall not be used
for general applications except for very high temperature or vibrating services with SABIC
approval. Remote mounted electro-mechanical positioners can be considered for such
applications.
12.2.3 The valve positioner shall have sufficient output capacity in both directions for pressuring
and venting the actuator to maintain the specified response times.
12.2.4 Positioner shall be direct acting i.e. signal failure and positioner air supply failure shall take
the valve to its failure position.
12.2.5 Positioners shall be rugged and have modular design to facilitate easy replacement and
interchangeability.
12.2.6 Positioner shall have adjustable tuning sets to provide flexibility in adjusting the instrument
responsiveness for the valve assembly and associated accessories.
12.2.7 Split ranging of the valves shall be achieved in the DCS with individual analog output signals
to each valve.
12.2.8 Positioner shall be equipped with air filter. Air pressure regulator shall be furnished if
specified air supply pressure is higher than the design pressure of the actuator.
12.2.9 Valve position transmitter shall be provided when specified in the valve data sheet.
12.3 Valve Position Switches / Limit Switches
12.3.1 Valve position switches/limit switches shall be proximity type, two wires with no external
power supply. Switches shall be with SS 316 casing and securely mounted for good
mechanical protection and preferably enclosed within a protective cover. Valve position
switches shall meet the specified hazardous electrical area classification requirement.
12.3.2 Limit switches shall be hermetically sealed and shall not be affected by the vibration.
12.3.3 Limit switches and solenoid valve shall be wired per SES-X05-E02.
12.4 Solenoid Valves
12.4.1 For safety or process interlock applications, solenoid valve shall be installed so that deenergizing
of
the
solenoid
coil
moves
the
valve
to
the
air
failure
position.
12.4.2 Solenoid valve shall be located between the positioner and the actuator, mounted on the
valve actuator.
12.4.3 When activated, solenoid valve shall provide sufficient capacity to exhaust the actuator
chamber air volume within the time required to permit the control valve to fail in a safe
position.
12.4.4 Low power, 24 VDC, three-way solenoid valves with SS 316 body and suitable for the
specified hazardous area classification shall be used, unless otherwise specified.
12.4.5 Solenoid valves shall be rated for continuous duty with class H insulation coil, as per IEEE
Std1. The ambient conditions including direct sunlight should not affect the performance of
solenoid valve.
12.5 Booster Relays / Quick Exhaust Valves
12.5.1 Booster relays and quick exhaust valves should be provided to increase the opening and
closing speed of valve.
12.5.2 Exhaust silencer should be installed at quick exhaust valve outlet.
12.5.3 Stability or balance adjustments shall be integral with the relay.
12.6 Lock Up Valve
12.6.1 Lock up valves shall be used for services requiring the valve to remain in the position
immediately before the failure of air supply.
12.6.2 Control valves specified as fail locked close (FLC) or fail locked open (FLO) shall be
furnished with lock up valves. Such valves shall act to lock-up the valve position by blocking
airflow to the actuator upon air supply pressure decay below the value required to fully
stroke the valve.
12.6.3 Lock up valves shall be installed close to the actuator, mounted between positioner output
and actuator.
12.6.4 Control valve with air locking system shall have pressure gauge installed after air lock
assembly to indicate actual diaphragm or piston pressure.
12.7 Handwheel
12.7.1 Handwheel shall be provided on the valves when local control is required, and handwheel is
specified on the data sheet.
12.7.2 Handwheel linkage mechanism shall be designed such that valve position does not change
while engaging the handwheel.
12.7.3 Handwheel mechanism shall not add friction to the valve actuator. Handwheel neutral
position shall be clearly identified.
12.8 Travel Stop
12.8.1 Travel stop to limit the valve travel in any or both directions should be lockable or equipped
with jam-nut arrangement.
12.8.2 Travel stops arrangements through the handwheel mechanism are not acceptable.
12.8.3 Travel stops in applications where control valve capacity Cv can impact the relief valve
capacity shall be made permanent. A permanent locking system or welded travel stop is
acceptable.
12.9 Air Filter Regulator
12.9.1 Combined air filter regulator shall be provided for all valves.
12.9.2 Filter regulator shall be reducing-relief valve type with drainage facility and pressure
adjustment bolt with a locking nut. It shall be mounted vertically on the actuator.
12.9.3 The cartridge of filter regulator shall be rigid structure type to avoid shrinkage, rupturing,
distortion or channeling, and shall have a mesh size of 5 microns.
12.9.4 The output capacity and spring range of the filter regulator should be suitable to the air
requirement for positioner, actuator and other installed accessories.
13. Special Requirements
13.1 Data Sheets
13.1.1 The following items can be added to the data sheet as required:
a. Extension bonnet, cavity relief arrangement, special stem packing for cryogenic services
per BS6364
b. Special packing arrangements, e.g. dual packing, Lantern ring with tapped and plugged
bonnet for packing flush or vent
c. Special trim hardening requirements
d. Zero clearance wiper ring or bushing
e. Oxygen or other special service cleaning
f. NACE materials of construction as per ISO 15156/MR0175 or MR0103
g. Alternate flange face finish
h. Soft-seat seal required
i. Balanced plug design
j. Special body configuration
k. Bellows seal
l. Hydrogen service requirement as per API 941
m. Internal polishing for slurry services
13.2 Identification
13.2.1 All internal trim parts of the control valve shall be identified by etching, manufacturer‟s
symbol and a unique part number.
13.2.2 Valve and actuator assemblies are to be marked in accordance with MSS-SP-25. Name
plates shall be attached to the actuator using stainless steel screws or SS rivets.
13.3 Metal Tag
13.3.1 Vendor shall provide a SS metal tag bearing valve tag number in lettering at least 6 mm (1/4
inch) high and securely attached to the control valve
13.4 Data Plate
13.4.1 All valves shall have a data plate permanently attached to the valve with all relevant
information.
13.4.2 Information for the valve body sub-assembly shall include:
a. Serial number
b. Type
c. Size
d. Port size
e. Rating
f. Plug/disc material
g. Stem/shaft material
h. Body material
i. Seat material
j. Manufacturer‟s name
13.4.3 Information for the actuator sub-assembly shall include:
a. Serial number
b. Type
c. Size
d. Bench set
e. Travel
f. Pressure units
g. Operating range
h. Casing/cylinder maximum pressure rating
13.5 Casting or Stamping
13.5.1 The valve body castings shall be marked with:
a. Heat/lot identification
b. Flow direction
c. Logo type
d. Bridge wall
e. Material identification
f. Foundry symbol and pattern number
g. Manufacturer‟s symbol and die number
h. Nominal size and ASME pressure rating
13.6 Information Provided by Vendor
13.6.1 Selected body and trim size capable of satisfactory operation over minimum and maximum
flow, temperature and pressure conditions as specified in the data sheet.
13.6.2 The actual flow Cv required at minimum, normal and maximum flow rate at the specified
process conditions.
13.6.3 The trim type, characteristics and selected Cv for the valve to meet all stated process
conditions and the maximum trim size that can be installed in the valve.
13.6.4 All information designated on the data sheet or in the general specification as “By Vendor.”
13.6.5 Calculations for valve flow coefficient, noise, cavitations, flashing, high exit velocities or any
other detrimental factors.
13.6.6 Quality assurance certificates that the castings meet the materials standards.
13.6.7 Alternative proposals on materials of construction, packing, and gaskets shall be furnished
for SABIC information and evaluation. Vendor‟s proposal shall follow the valve specification
as given on the data sheet or general specification.
13.6.8 Valve face-to-face and overall height from valve body centerline dimension shall be
furnished with vendor‟s quotation.
13.6.9 Procedure for the removal of body top work and re-installation after welding for the welded
end type control valves shall be furnished.
13.6.10 The required number of copies of dimensional drawings, manuals, and parts lists shall be
furnished as requested in the purchase order. Parts lists shall clearly indicate identification
and material of construction of the various parts for each valve or groups of identical valves.
Parts lists shall designate vendor recommended maintenance stock items.
13.7 Shipping
13.7.1 Valves shall have all openings sealed or covered for shipment. Carbon steel flange gasket
surfaces shall be coated with anti-rust compound. Air connections shall be closed with
plastic plugs. Inlet and outlet of body are to be closed with securely fastened covers suitable
to prevent gasket face damage in shipment or storage.
13.7.2 Valves shall be shipped in a ready-for-use condition, e.g., bonnet tightened, packing fully
loaded and all accessories installed and ready for use.
13.7.3 Valves shipped in crates or boxes shall be clearly labeled on the outside with the project
number, purchase order number, and valve tag number.
13.8 Inspection and Testing
13.8.1 The minimum inspection and testing requirements are included in SES-R07-T01.
13.8.2 Control valve dynamic performance test, shall be performed only to selected control valves,
as indicated in project specifications.