Air Operated Control Valves.pdf

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TECHNICAL SPECIFICATION

AIR OPERATED CONTROL VALVESI2210E

DATE: 01 NOV 2005 ENGINEERING SERVICES BY KBR TECHNICAL SERVICES, INC. PAGE 1 OF 7

TABLE OF CONTENTS

Section Title Page No. 1. GENERAL ......................................................................................................................................11.1 Scope..............................................................................................................................................11.2 Codes and Industry Standards .......................................................................................................12. DESIGN AND MATERIALS ...........................................................................................................22.1 General ...........................................................................................................................................22.2 Body and Bonnet ............................................................................................................................32.3 Control Valve Actuators..................................................................................................................42.4 Bolting and Gaskets........................................................................................................................52.5 Trim.................................................................................................................................................6

2.6 Fugitive Emissions Considerations.................................................................................................62.7 Control Valve Accessories..............................................................................................................63. TESTING ........................................................................................................................................63.1 Operation and Seat Leakage..........................................................................................................63.2 Pressure Testing.............................................................................................................................73.3 Alloy Verification Testing ................................................................................................................74. EQUIPMENT IDENTIFICATION.....................................................................................................7

1. GENERAL

1.1 Scope

1.1.1 Air operated control valves shall be supplied in accordance with an approved quality managementprogram and in strict compliance with:

Attached Data SheetsThis SpecificationIndustry Codes

1.1.2 Where special features or improvements over the standard specification are required, these shall bespecified on the Instrument Data Sheets and shall be adhered to by the Supplier.

1.2 Codes and Industry Standards

The documents listed below are referenced herein and form a part of the Order. Applicable Codes andIndustry Standards are indicated below and refer to the latest issue of the referenced document in effect atplacement of the initial Purchase Order. Unless approved otherwise by purchaser’s responsible engineer,

equipment shall be supplied in accordance with applicable requirements of these documents, asdetermined/clarified by same engineer.

AMERICAN SOCIETY OF MECHANICAL ENGINEERS (ASME) ASME Boiler and Pressure Vessel Code, including all mandatory addenda

Section VIII, "Pressure Vessels - Division 1"

ASME B1.20.1, "Pipe Threads, General Purpose (Inch)" ASME B16.5, "Pipe Flanges and Flanged Fittings NPS 1/2 Through NPS 24" ASME B16.11, "Forged Fittings, Socket-Welding and Threaded" ASME B16.20, "Metallic Gaskets for Pipe Flanges - Ring-Joint, Spiral-Wound, and Jacketed" ASME B16.25, "Buttwelding Ends"

ASME B16.34, "Valves – Flanged, Threaded and Welding End" ASME B16.47, "Large Diameter Steel Flanges NPS 26 Through NPS 60" ASME B31.3, "Process Piping"






AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) ASTM A105/A105M, "Carbon Steel Forgings for Piping Applications" ASTM A182/A182M, "Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and

Valves and Parts for High-Temperature Service" ASTM A193/A193M, "Alloy Steel and Stainless Steel Bolting Materials for High-Temperature Service" ASTM A194/A194M, "Carbon and Alloy Steel Nuts for Bolts for High-Pressure and High-Temperature ASTM A216/A216M, "Steel Castings, Carbon, Suitable for Fusion Welding, for High-Temperature Service" ASTM A217/A217M, "Steel Castings, Martensitic Stainless and Alloy, for Pressure-Containing Parts,

Suitable for High-Temperature Service" ASTM A320/A320M, "Alloy-Steel and Standard Steel Bolting Materials for Low-Temperature Service" ASTM A350/A350M, "Carbon and Low-Alloy Steel Forgings, Requiring Notch Toughness Testing for

Piping Components" ASTM A352/A352M, “Steel Castings Ferritic and Martensitic for Pressure-Containing Parts Suitable for

Low-Temperature Service"

FLUID CONTROL INSTITUTE (FCI)FCI 70-2, "Control Valve Seat Leakage"

INSTRUMENT SOCIETY OF AMERICA (ISA)ISA 75.08.01 "Face-To-Face Dimensions for Integral Flanged Globe-Style Control Valve Bodies

(Classes 125, 150, 250, 300, and 600)"ISA 75.08.02, "Face-To-Face Dimensions for Flangeless Control Valve Bodies

(Classes 150, 300, and 600)"ISA 75.08.05, "Face-to-face Dimensions for Buttweld-End Globe-Style Control Valves

(Classes 150, 300, 600, 900, 1500, and 2500)ISA 75.08.06, “Face-To-Face Dimensions for Flanged Globe-Style Control Valve Bodies(Classes 900, 1500, and 2500)"

ISA 75.14, "Face-To-Face Dimensions for Buttweld-End Globe-Style Control Valves(ANSI Class 4500)"

ISA 75.19.01, "Hydrostatic Testing of Control Valves"

2. DESIGN AND MATERIALS

2.1 General

2.1.1 Valve bodies shall be of the material specified on the Instrument Data Sheets. As a minimum, thevalve trim and stem shall be of stainless steel, suitable for the specified design conditions.

2.1.2 Unless otherwise specified, carbon steel valves shall be painted in accordance with Supplier'sstandards suitable for the environmental, operating and design conditions specified on the Instrument DataSheets.

2.1.3 Minimum valve end connection size shall be NPS 1 for valves installed in lines NPS 1 and larger.

2.1.4 Valves installed in lines smaller than NPS 1 shall be line size.

2.1.5 Valves that must provide tight shutoff shall have a Class IV seat leakage rating, as a minimum. Therequired shut off class will be shown on the data sheet.

2.1.6 Valves in critical applications that require minimum leakage shall have Class VI seat leakage rating.Class V will be acceptable if temperature limits are outside of soft seat materials.






2.1.7 For Rotary valves:

a. The valve disk shall be positively attached to the shaft, and the shaft shall preferably be a one-piece,through design.

b. The actuator end of the valve shaft shall be splined or keyed and shall not have a shear pin.

c. The valve shaft bearing shall be designed to prevent the shaft guide bushing from rotating in the valvebody.

d. The bearing material shall be selected to prevent galling of the bearing or valve shaft.

e. Since the disk in wafer style valves may project beyond the valve body during part of the disk rotation,clearance shall be maintained between the disk and the pipe wall, particularly if the pipe is of heavy wallconstruction.

f. For butterfly valves, the vane as a minimum shall be of the same material as the valve body, unlessotherwise specified.

g. Wafer valves shall have centering holes to ensure proper alignment of valve and gasket.

2.1.8 Material, end connections, and pressure rating of valve body shall conform to the applicable pipingspecification, as a minimum.

2.2 Body and Bonnet

2.2.1 Direction of flow shall be indicated on all valve bodies. Direction arrow must be forged, stamped, orotherwise permanently attached.

2.2.2 Cage guided valves shall have removable cages. All globe valves shall have removable seat rings andplugs. Threaded seat rings are not acceptable.

2.2.3 The valve stem shall be sealed by means of a bolted packing box. Packing glands shall be equippedwith flange style followers. Packing shall be as follows unless process fluid or conditions require others:

a. Temperature 0 to 450 °F (-17.8 to 232 °C) – Use TFE V-Ring.

b. Temperature below 0 °F (-17.8 °C) or above 450°F (232 °C) – Use Laminated graphite.

A lubricator and an isolating valve shall be provided when required on the instrument data sheet.

2.2.4 The erosive/corrosive effects of the controlled fluid and the design life of the plant shall be consideredwhen deciding valve body material.

2.2.5 Ratio of nominal pipe size to body size greater than 2:1 shall be approved by Purchaser.

2.2.6 Valve end connection sizes, types, and facings shall be as specified on the Instrument Data Sheets,and shall be in accordance with the following standards:






Threaded (tapered style required) ............ ASME B1.20.1Flanged NPS 1/2 through NPS 24............ ASME B16.5Flanged NPS 26 and larger....................... ASME B16.47 (*) Ring Joint (flat-bottom type grooves)........ ASME B16.20Buttwelded ................................................ ASME B16.25Socket-welded........................................... ASME B16.11

(*) Supplier to designate Type A or B style flanges on quote.

2.2.7 Bonnets shall be a bolted design.

2.2.8 Single and double seated straight through valves with flanged end connections shall have face-to-facedimensions in accordance with ISA 75.03 or ISA S75.16.

2.2.9 Unless noted otherwise and in addition to the above requirements, all cast, forged, and fabricated steelvalves shall be manufactured as "Standard Class" valves in accordance with ASME B16.34.

2.2.10 Unless specified otherwise, all materials, design and fabrication of valves including any requiredexamination, inspection, testing, and acceptance criteria, shall be in accordance with the requirements andlimitations of ASME B31.3. This includes any maximum temperature limitation for a material or rulegoverning the use of a material at a low temperature.

2.2.11 Globe valves with split body shall be used only with prior Purchaser approval.

2.2.12 Face-to-face dimensions of the valve body shall conform to ISA Standards in accordance with thefollowing table:

BODY STYLE ISA STANDARD

Globe style 75.08.01 or 75.08.06 depending on Integral Flanges ASME Class rating

Flangeless 75.08.02

Buttweld-End Globe 75.14 or 75.08.05 depending on ASME Class rating

2.3 Control Valve Actuators

2.3.1 Unless otherwise specified, valve actuators shall be pneumatic diaphragm type or piston type.

2.3.2 Where springless type cylinder actuators are required, e.g., high thrust applications, etc., the actuatorsshall be furnished with the necessary volume (capacity) tank and accessories to provide the correct valveaction on air supply or signal failure. Tank capacity shall be capable of fully stroking the valve two (2)complete cycles.

2.3.3 All volume tanks shall conform to Part U-1 of ASME Section VIII, Division 1, and shall be ASME Codestamped. The tanks shall be equipped with a pressure relief device, a pressure gauge, a drain valve, andsupport steel such as “L” shaped legs for mounting. Supplier shall make recommendations for large tanksupport requirements.

2.3.4 Actuator shall drive the valve to a safe position on loss of signal or motive power. Actuator shall havean enclosed spring to achieve fail-safe action. Multispring actuators are not acceptable.






2.3.5 Actuator shall be sized:

a. By the valve supplier.

b. To meet control, shutoff, and leakage requirements of the valve, at minimum air supply.

c. To fail the valve to the safe position on loss of air or control signal. The valve shall return to requiredfailsafe position using spring force only.

d. Per the maximum differential pressure (shutoff pressure specified on valve datasheet) or if not shown,then the maximum differential pressure shall be the maximum process upstream pressure with valvefully closed and downstream at atmospheric pressure whichever is greater. Using process pressure to

assist valve movement shall not be considered in the calculation with the spring force to maintaincontrollability, fail safe state and/or shutoff classification of the valve.

e. With a 1.2 design factor for valves in a process service where the valve stems could stick.

2.3.6 Actuator case shall be rated for the maximum available pneumatic supply pressure, or a supplyregulator shall be provided.

2.3.7 Exterior of actuator shall be painted with Supplier’s standard paint and color, unless specifiedotherwise.

2.3.8 Actuator and associated accessories shall be completely assembled, piped, mounted on the controlvalve, aligned, tested, and shipped as a complete unit.

2.3.9 Actuator shall be capable of providing a full stoke of the control valve in either direction in not morethan 20 seconds, unless specified otherwise on the Instrument Data Sheet.

2.3.10 Springs, internal parts, fasteners, and hardware shall be resistant to corrosive effects of theenvironment.

2.4 Bolting and Gaskets

2.4.1 Bolting material shall be compatible with body and bonnet material.

2.4.2 Bolts shall conform to ASTM specifications as follows:

Valve Body Material Bolting/Nut MaterialsCarbon steel, ASTM A105 or A216-WCB ASTM A193-B7 / A194-2HLT Carbon steel, ASTM A350-LF2 or A352-LCB ASTM A320-L7 / A194-41-1/4 Cr-1/2 Mo, ASTM A182-F11 or A217-WC6 ASTM A193-B16 / A194-42-1/4 Cr-1 Mo, ASTM A182-F22 or A217-WC9 ASTM A193-B16 / A194-4300 Series Stainless Steel, -50 to 1000 °F ASTM A193-B8 CL2 / A194-8MA or 8TA300 Series Stainless Steel, -325 to -51 °F ASTM A320-B8 CL2 / A194-8MA or 8TA

2.4.3 The valve Supplier shall supply cap screws for single flange valves in accordance with the pipingspecification.






2.4.4 Bonnet gaskets shall:

a. Be fully retained.b. Be made from 316 SS, unless otherwise specified.c. Have PTFE or graphite filler.

2.5 Trim

2.5.1 Valve stem and plug shall be pinned, welded, or one-piece design.

2.5.2 Threaded trim parts shall be pinned or spot-welded to supplement threaded attachment.

2.5.2 Bonnet bolts shall not be used to attach actuators or mounting brackets.

2.6 Fugitive Emissions Considerations

2.6.1 Packing shall limit fugitive emissions.

2.6.2 Bellows seals should be considered only when no leakage across the stem can be tolerated, or casesin which excessive packing friction results in unreasonably large packing friction forces.

2.7 Control Valve Accessories

2.7.1 Side mounted handwheels, when specified on the Instrument Data Sheets, shall be of locking typewith de-clutching mechanism.

2.7.2 Solenoid valves shall be rated for continuous duty and shall have Class F high temperatureencapsulated coils. Class H shall be used in high ambient temperature applications only. Coil voltage shallbe 24 V DC, unless specified otherwise on the data sheets.

2.7.3 Solenoid valve for tripping the control valve shall be between the positioner and the actuator or in thetubing providing the motive power to the actuator.

2.7.4 Tripping solenoid valve shall have sufficient capacity to exhaust the actuator chamber air volumewithin the time required to allow the valve to fail in a fail safe position. If the solenoid valve Cv is notsufficient, a pilot valve shall be provided with separate airset, which works in conjunction with the trippingsolenoid valve.

2.7.5 The Supplier shall provide bonnet extension when necessary or when specified, to ensure properoperation of the control valve under the operating and design conditions specified on the Instrument DataSheet.

2.7.6 If the solenoid valve vent port is open to the atmosphere, it shall have an insect screen.

2.7.7 As a minimum, the positioner shall be a “smart” positioner with 4-20 ma for signal transmission andHART data collection. See the data sheets for specific project requirements.

3. TESTING

3.1 Operation and Seat Leakage

Seat leakage tests shall be in accordance with FCI 70-2.






3.2 Pressure Testing

As a standard requirement, all valves shall be hydrostatically tested in accordance with ISA S75.19.01.Unless otherwise stated on the data sheet, component testing of the pressure boundary parts is permitted;provided the valve body assembly is subsequently tested to verify the pressure sealing integrity of gaskets.

3.3 Alloy Verification Testing

An alloy verification plan will be issued on projects where alloy verification is required in accordance withGeneral Engineering Procedures. This plan will include instrument items to be alloy verified (with verificationclass defined), required methods of verification and when and where these test are to be performed. Alloyverification requirements will be noted on each valve data sheet (Example: “CLASS I ALLOY VERIFICATION

REQUIRED”). Supplier shall perform all required tests to meet the stated requirements.

4. EQUIPMENT IDENTIFICATION

The Supplier shall provide a separate (from the valve and/or actuator nameplate) stainless steel tag attachedto the valve (in a corrosion resistant manner). The valve tag number and purchase order number shall bestamped upon it.

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Air Operated Control Valves.pdf