SPEC CONTROL VALVE

. GENERAL REQUIREMENTS

a) The control valves and accessories equipment furnished
by the bidder shall be designed. constructed and tested
in accordance with the latest applicable requirements of
code for pressure piping ANSI, the ASME Boiler &
pressure vessel code, Indian Boiler Regulation(IBR), ISA
and other standards specified elsewhere as well as in
accordance with all applicable requirements of the
"Federal Occupational Safety and Health standards, USA"
or acceptable equal standards. All the Control Valves,
their actuators and accessories to be furnished under
this section will be fully suitable and compatible with
the modulating loops covered under SG C&I, TG C&I and
closed loop control system of the specification.
b) All the control vales and accessories offered by the
bidder, shall be from reputed experienced manufacturers
of specified type and range of valves.

02.00 CONTROL VALVE SIZING & CONSTRUCTION

02.01 The design of all valve bodies shall meet the
specification requirements and shall conform to the
requirements of ANSI(USA) for dimensions, material
thickness and material specification for their
respective pressure classes.

.02.02 The valve sizing shall be suitable for obtaining maximum
flow conditions with valve opening at approximately 80%
of total valve stem travel and minimum flow conditions
with valve stem travel not less than 10% of total valve
stem travel. All the valves shall be capable of
handling at least 120% of the required maximum flow.
Further, the valve stem travel range from minimum flow
condition to maximum flow shall not be less than 50% of
the total valve stem travel. The sizing shall be in
accordance with the latest edition of ISA standard
"ANSI/ ISA-75.01.01, Flow Equations for sizing of
control valves." While deciding the size of valves,
bidder shall ensure that valves outlet velocity does not
exceed 8 m/sec for liquid services, 150 m/sec for steam
services and 50% of sonic velocity for flashing
services. Bidder shall furnish the sizing calculations
clearly indicating the outlet velocity achieved with the
valve size selected by him as well as noise
calculations as per ISA-75-17-1989 "Control valve
Aerodynamic Noise Prediction" which will be subject to
Owner’s approval during detailed engineering.
02.03 Control valves for steam and water applications shall be
designed to prevent cavitations, wire drawing, flashing
on the downstream side of valve and down stream side of
valve and down stream piping. Thus for cavitations/
flashing service, only valve with anti cavitations trim
shall be provided. Detailed calculations as per ISA-RP-
75-23-1995 "Consideration for evaluating control valve
cavitations" to establish whether cavitations and erosion
will occur or not for any given application shall be
furnished. Bidder shall furnish the calculations ,
which will be subject to Owner’s approval during detailed engineering.
02.04 The control valve induced noise shall be limited to 85
db A at 1 Mtr. from the valve surface under actual
operating conditions. The noise abatement shall be
achieved by valve body and trim design and not by use of
silencers.

02.05 The characteristic of the control valves shall be
determined based on the application/ service.

.02.06 Valve Construction

i) All valves shall be of globe body design & straightaway
pattern with single or double port. Unless other wise
specified or recommended by the manufacturer to be of
angle body type. Rotary valve may alternatively be
offered when pressure and pressure drops permit.

ii) Valves with high lift cage guided plugs & quick change
trims shall be supplied.

iii) Cast iron valves & asbestos packing are not acceptable.

iv) Bonnet joints for all control valves shall be of the
flanged and bolted type or other construction
acceptable to the bidder. Bonnet joints of the internal
threaded or union type will not be acceptable. the material of bonnet shall be same as body
v) Plug shall be of one-piece construction either cast,
forged or machined from solid bar stock. Plug shall be
screwed and pinned to valve stems or shall be integral
with the valve stems.

vi) All valves connected to vacuum on down stream side shall
be provided with packing suitable for vacuum
applications(e.g. double vee type chevron packing). For
other valves packing material shall be Grafoil/double.

vii) Valve characteristic shall match with the process
characteristics.

viii) Extension bonnets shall be provided when the maximum
temperature of flowing fluid is greater than 280 Deg.C.

ix) Flanged valves shall be rated at no less than ANSI press
class of 300 lbs.

x) If the down stream is subjected to vacuum, flow
direction of fluid shall be to close.

xi)Leakage Class

Control valves for application such as HP/LP Heater
emergency level control, SH spray & RH spray control,
Emergency makeup to Hotwell, deaerator drain to condenser
hotwell, & heavy oil heating, HFO & LDO and pressuring and
control system, condenser normal make-up and valve shall

have permissible leakage rate as per leakage Class - V
(ANSI/ FCI). All other control valves such as low and high
range feed control valves, LP/HP heaters normal/ level
control valves etc. shall have leakage rate as per leakage
Class-IV. All SH/RH Block valves, shut-off valve of LDO &
HFO and BFP recirculation valve shall have leakage class
MSS-SP-61.

VALVE MATERIALS

The control valve body/trim material shall be -
(i) Non corrosive, non flushing and non cavitation service
below 280 Deg.C like Aux.steam flow to deaerator, cond.
flow to deaerator, CRH flow to deaerator.

a) Body Material - The body material shall be carbon steel
ASTM-A 216 Gr.WC B except CRH flow to deaerator and
alloy steel ASTM A 217 Gr.WC 9 for CRH flow to deaerator.

b) Trim Material - The trim material shall be 316 SS
stellite faced guide and bushings.

(ii) Severe flashing/cavitation services like feed control
valve, spray control valve (SH & RH Spray control
and block valve) L P heater & H P heaters. Emergency level
control valve, HPBP Spray control valve, deaerator over
drain etc.

a) Body Material shall be ASTM A 217 WC 9.

a) Trim material shall be 440 C series SS

(iii) Low flashing/ cavitations service like HP heater/ LP
heater normal level control, Condensate/feed water below
280 Deg.C etc.

a) Body Material shall be Alloy Steel as per ASTM A 217 WC6.

b) Trim material shall be 17-4 PH SS

(iv) Normal & Emergency make up D M water control

a) Body Material shall be A 351 Gr CF 8M

b) Trim Material shall be 316 SS +ST

(v) Fuel oil and atomising steam service

a) Body Material shall be Alloy Steel ASTM A 216 WCB.

b) Trim material shall be 316 SS stellite.

However, bidder may offer valves with body and trim
materials better than specified materials and in such,
cases bidder shall furnish the comparison of properties
including cavitation resistance, hardness, tensile
strength, strain energy, corrosion resistance and
erosion resistance etc. of the offered material vis-a-
vis the specified material for bidder's consideration and
approval.
03.00 The anti cavity trim of following control valve shall be multi stage multi path velocity head loss type:
i)low load feed control valve
ii)SH,RH,PRDS,HBPS spray control valves
iii)CEP & BFP min recirculation valves.

All other anti cavity trim shall be multistage type.

ANTI CAVITY TRIM
03.02. However, bidder may offer valves with body and trim materials better than specified materials and in such, cases bidder shall furnish the comparison of properties including cavitation resistance, hardness, tensile strength, strain energy, corrosion resistance and erosion resistance etc. of the offered material vis-a-vis the specified material for bidder's consideration and approval.
.04.00 END PREPARATION

Valve body ends shall be either butt welded/ socket
welded, flanged or screwed as finalised during detailed
engineering and as per owner approval. The welded
ends wherever required shall be butt welded type as per
ANSI B 16.25 for control valves of sizes 65 mm and
above. For valves sizes 50 mm and below welded ends
shall be socket welded as per ANSI B 16.11. Flanged
ends wherever required shall be of ANSI pressure
temperature class equal to or greater than that of the
control valve body.

05.00 Performance of Valve
i) linearity :1% of FS.
ii)Hysterisis :1% of FS.
iii)Sensitivity :0.5% of span.
iv)Accuracy : 2% of span.

06.00 VALVE ACTUATORS

(a)All control valves shall be furnished with pneumatic
actuators. The Bidder shall be responsible for proper
selection and sizing of valve actuators in accordance
with the pressure drop and maximum shut off pressure and
leakage class requirements. The valve actuators shall
be capable of operating at 60 Deg.C. continuously. Valve
actuators and stems shall be adequate to handle the
unbalanced forces occurring under the specified flow
conditions or the maximum differential pressure
specified. An adequate allowance for stem force,
atleast 0.15 Kg/Sq.Cm. per linear millimeter of seating
surface, shall be provided in the selection of the actuator to ensure tight seating unless otherwise specified. The travel time of the actuators shall not exceed 10 secs.

.07.00 CONTROL VALVE ACCESSORY DEVICES
a) All control valve accessories such as positioner, air filter regulator, air lock relay, position limit switch, position transmitter, solenoid valve, E/P converter, junction box, hand wheel, local position indicator, electro pneumatic positioner ,volume booster, fail freeze type IP Converter etc. shall be provided as per the requirements.
b) All valve control valve shall be provided with smart digital microprocessor based valve positioners and compatibility for remote calibration & superimposed HART signal on input signal 4-20 m Amp & connected with hart management system.
c)All field instrument mounted on the Control Valve shall be IP- 65/NEMA 4.
08.00 TEST AND EXAMINATION

.08.01 All valves shall be tested in accordance with the
quality assurance program agreed between the owner
and contractor which shall meet the requirements of IBR /ASME
and other applicable codes mentioned elsewhere in the
specifications. The tests shall include but not be
limited to the following:-

1) Non Destructive Test as per ANSI B-16.34

2) Hydrostatic shell Test in accordance with ANSI B 16.34
prior to seat leakage test.

3) Valve closure test and seat leakage test in accordance
with ANSI-B 16.34 and leakage class test as per ANSI/FCI
70.2.1998.

4) Functional Test : The fully assembled valves including
actuators control devices and accessories shall be
functionally tested to demonstrate times from open to
close position.

5) CV Test: CV & FL(Liquid Pressure Recovery Factor) test
shall be carried out as type test on each size, type
and design of the valves as per ISA 75.02 standard.
6) The all above tests shall be witness by OWNER

7)Bidder shall submit material test certificate, Radiographic Evaluation report, ultra sonic test report, heat treat report ,IBR certificate Form IIIC etc. as per IBR/ASME for review and approval along with Factory Acceptance Test Report.
.09.00 . Bidder shall furnish all the control valves as finalised
during detailed Engineering. stage without any price repercussions whatsoever depending on the process
requirements including the systems under SG C&I and TG
C&I. All the control valves provided by the bidder for
this project shall meet the specifications requirements
specified herein. Specification for control valves in
this section has to be read in conjunction with other
relevant sections of the specification for this project.

.10.00. Bidder shall provide all type of gasket, gland packing
with each control valves as spare.

.11.00 For all remote operated control valves provide:
i) 100% bypass control valve, shall be motor operated inching type and exactly identical to main control valve.
ii) Separate power(motor) operated isolation valve on upstream side and manually isolation valve on down stream side.
iii) Pressure gauge and drain at inlet and outlet of each main control valve

12.00 SMART POSITIONER shall be a Double stage positoner. The first stage of the positioner shall be typically a flapper-nozzle that serves as a high-gain pre-amplifier. This sensitivity shall be maintained over a wide range of dynamic conditions. Second stage shall be a power amplifier that provides power to drive the actuator. Preferably this shall be a pneumatic relay. Spool Driven type SMART positioners are not preferred due to Higher Dead Band and Poor responsiveness. The SMART positioner shall have pressure sensors to measure the pneumatic outputs to the actuator.
The control algorithm for the positioner shall use feedback signal from the motion of the pneumatic relay beam instead of pressure feedback to minimize pneumatic related effects and for stable and smooth response of the control valve. The SMART positioner shall have user adjustable tuning sets to identify the optimum tuning for the total valve assembly.
SMART Positioner with HART Communication facility shall communicate all the valve diagnostics to DCS.
The electrical housing shall be designed to meet NEMA 4X

VENDERS
1.COPES VULCON,UK http://www.copsvulcon.com/
2.DRESSER MASONEILAN,FRANCE http://www.masoneilan.com/
3.FISHER CONTROLS,USA/UK
4.MIL,INDIA www.milcontrols.com
5 IL,INDIA
5.CCI,USA www.ccivalve.com

ref:
Control valve tutorials Tutorials covering the sizing, capacity and characteristics of control valves. Actuators, positioners, controllers and sensors are also discussed - Spirax Sarco
Control Valve Handbook (4th Edition) A 297-page online book.
Process Instrumentation (Lecture 8): Control valves Article from a University of South Australia website.
CARRARO control valve
Control Components Inc Website for severe service control valve.
Valve Animations Flash animations demonstrating conventional and pressure independent control valve operation.
Dorot Control Valves
[1]Azbil (formerly known as Yamatake) control valve
Samson AG Demo Valve Sizing Software. Basic Trial valve sizing programme.
CONVAL - the PC software for engineers, planners and operators of industrial plants.

FREE SOFTWARE CONTROL VALVE SIZING 1,FIRSTVUE Sizing Software (Version 1.0.ab) Emerson FISHER

2.ValSpeQ Dresser-Masoneilan

3.ValveWorks Warren Control

4.Control Valve Sizing Program Welker Engineering

IEC 60534-1 Part 1: Control Valve Terminology and General Considerations, 2005
IEC 60534-2-1 Part 2-1: Flow Capacity; Sizing Equations for Fluid Flow Under Installed
CONDITION

SPEC CONTROL VALVE

Friday, July 31, 2009

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