PDVSA k-301

PDVSA N° TITLE

VOLUME 9–I

PRESSURE INSTRUMENTATION

ENGINEERING SPECIFICATION

ENGINEERING DESIGN MANUAL

K–301

REV. DATE DESCRIPTION PAG. REV. APPD. APPD.

APPD.BY DATEDATE

�1994

FOR APPROVAL

Alexis Arévalo Jesús E. RojasDEC.99 DEC.99

AUG.94

DEC.99 Y.K.

L.T.

1

0

REVISION GENERAL 7

7

A.A.

E.J.

J.E.R.

A.N.

APPD.BY

ESPECIALISTAS

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REVISION DATE


PRESSURE INSTRUMENTATIONPage 1

DEC.991

PDVSA K–301

Menú Principal Indice manual Indice volumen Indice norma

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Indice1 SCOPE 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 CODES, STANDARDS AND PRACTICES 2. . . . . . . . . . . . . . . . . . . . .

3 DEFINITIONS 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 SELECTION AND SPECIFICATION 2. . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1 General 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2 Principles of Selection 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Units of Measurement 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 Selection of Ranges 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5 General Design Requirements 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6 Pressure Gauges Connected to Process 4. . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7 Pressure Transmitters and Transducers 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8 Pressure Gauges – Pneumatic Receiver Type 4. . . . . . . . . . . . . . . . . . . . . . 4.9 Pressure Controllers/Recorders – Field Mounted 4. . . . . . . . . . . . . . . . . . . . 4.10 Pressure Controllers/Recorders – Panel Mounted 5. . . . . . . . . . . . . . . . . . . 4.11 Pressure Switches 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 MODIFICATIONS, ADDITIONS AND DELETIONS (EXCEPTIONS) OFAPI 551 SECTION 4 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1 Scope 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 General 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 Pressure Gauges and Switches 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4 Pressure Transmitters 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 Section 6 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6 PDVSA SPECIFICATION FORMS 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 QUALITY ASSURANCE/QUALITY CONTROL 7. . . . . . . . . . . . . . . . .

http://www.intevep.pdv.com/santp

http://www.intevep.pdv.com/santp/mid/indice_mid.htm

http://www.intevep.pdv.com/santp/mid/vol09-1/indice_vol09-1.htm

REVISION DATE



DEC.991

PDVSA K–301


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1 SCOPEThis section covers PDVSA requirements for the design, specification, installationand commissioning of pressure instrumentation. Guidelines of specificationK–300 shall also be applicable.

API–551 sections 4 and 6 have been accepted by PDVSA as its own standard forpressure device installation, with the amendments indicated in this document.

The requirements of this specification are modifications, additions and/ordeletions (exceptions) to API 551 “Process Measurement Instrumentation”sections 4 and 6. The section, paragraph, item, table and figure numbers and theassociated headings used in this specification correspond to the ones used in API551, First edition, May. 1993. Since this specification does not take exception toall the requirements in API 551 SECTIONS 4 AND 6, thesection/paragraph/item/table/figure numbers in this specification may not besequential. It’s clearly understood that section, paragraph, items, tables or figuresof API 551 sections 4 and 6 not mentioned in this specification have been adoptedwithout changes.

2 CODES, STANDARDS AND PRACTICESPDVSA K–300 Introduction to PDVSA InstrumentationPDVSA K–369 Instrumentation QA/QCISA S20 Specifications Forms for Process Measurement and

Control Instruments, Primary Elements and ControlValves.

ASME B1.20.1 Pipe Threads, General Purpose (inch)ASME B40.1 Gauge – Pressure Indicating Dial Type – Elastic

ElementANSI

3 DEFINITIONSAll definitions are listed in the appendix of PDVSA standard K–300.

4 SELECTION AND SPECIFICATION

4.1 GeneralThe selection and specification of all instruments for process applications, utilities,etc. shall be done in accordance with the following procedure.

1. Define measurement options and decide upon the optimum for theapplication.




REVISION DATE



DEC.991

PDVSA K–301


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2. Select the manufacturers and types of instruments from the “List of SelectedInstrument Vendors” as prepared by PDVSA representative.

3. Select the accuracy and range of the instrument to suit the processrequirements.

4.2 Principles of SelectionThe following items shall be defined for instrument selection:

1. Instrument purpose (Indication, control, transmitter, etc.).

2. Process conditions, such as fluid phase, viscosity, corrosiveness,erosiveness, toxicity, temperature, pressure, etc., under normal andabnormal conditions.

3. Environmental conditions, electrical area classification and mechanicalintegrity (piping class, vibration, etc.).

4. Ranges and accuracy classes shall be selected according to the processdata sheets.

5. Calibration facilities, possible cross contamination of process fluids and theneed to wash before removal (purge, flush and disposal) shall be identifiedas these will influence the instrument selection for the process condition(normal, abnormal, start–up and shut–down).

6. Maintenance aspects such as access, ease of installation, calibration andremoval and remote of self–diagnostic features shall be considered.

4.3 Units of MeasurementThe instrument ranges and scales shall be according to plant criteria unlessotherwise specified in the project specification.

4.4 Selection of Rangesa. The selected range shall be such that the normal operating condition is

approximately at mid scale and that the maximum process operatingpressure does not exceed 80% of the range of the indicating instrument orblind self acting regulator.

b. Instruments shall have over–range protection of 1.2 times the maximumpressure to which they may be exposed.

c. Instruments exposed to vacuum shall have under–range protection to fullvacuum.

4.5 General Design Requirementsa. Instruments measuring absolute pressure shall be compensated for

barometric pressure changes.




REVISION DATE



DEC.991

PDVSA K–301


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b. Instrument air supply and transmission connections shall be 1/4” N.P.T. Theelectrical connection shall be 1/2” N.P.T.F.

c. Pressure indicating pointers shall be adjustable with a micrometer typescrew.

d. Panel mounted pressure gauges, indicating or recording instrument andcontroller shall be flush or wall mounted.

e. Blind pressure controllers shall not be used.

f. Pressure gauges connected to process shall have a blow out disc in theback.

4.6 Pressure Gauges Connected to Process4.6.1 Pressure gauges shall conform to ASME/ANSI B 40–1.

4.6.2 The pressure gauge measuring element shall be bourdon, bellows or diaphragmtype depending upon the application and measuring range.

4.6.3 The element on furnace draft measurement service shall be slack diaphragmtype.1.

4.6.4 Pressure gauges shall not have suppressed ranges.

4.7 Pressure Transmitters and Transducers

4.7.1 They shall be solid state with analog or digital transmission. Pneumatic 3–15P.S.I.G. output types shall be used where necessary and subject to PDVSAapproval.

4.7.2 Suppressed and/or elevated zero ranges shall be used to enhance processmeasurement accuracy, readability and performance. All such ranges shall beagreed with PDVSA.

4.8 Pressure Gauges – Pneumatic Receiver Type

4.8.1 Pressure gauges shall conform to ASME/ANSI B 40–1.

4.8.2 The pressure gauge measuring element shall be bourdon.

4.8.3 The case and pressure element for gauges located inside air–conditioned controlrooms shall be manufacturer’s standard.

4.8.4 On items such as positioners, electro–pneumatic transducers, air filter regulatorsets, the dial size shall be 1 1/2 inches minimum.

4.9 Pressure Controllers/Recorders – Field Mounted

4.9.1 The elements shall be bourdon, spiral, helix, bellows or diaphragm typedepending upon the service and process pressure range to be measured.




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DEC.991

PDVSA K–301


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4.10 Pressure Controllers/Recorders – Panel Mounted

4.10.1 These may be mounted on local panels or inside the control room. Refer to API551 section 4, item 4.2.2 “Application Practice”.

4.10.2 Same as 4.9.

4.11 Pressure Switches

4.11.1 The pressure elements shall be bourdon, bellows or diaphragm type dependingupon the pressure range to be measured and the required switch differential.

4.11.2 The switches shall be micro type rated for 1 amp at 24 volts D.C. All other ratingsshall be subject to PDVSA approval.

4.11.3 The switch differential (fixed or adjustable) shall comply with all necessaryprocess operating conditions.

4.11.4 The switches shall be double pole double throw (D.P.D.T.) type with three wiresconnected to three terminals in order to select either a normally open (N.0.) ornormally closed (N.C.) action.

4.11.5 The maximum number of independent switches actuated by one pressureelement shall be two. Exceptions shall be approved by PDVSA.

5 MODIFICATIONS, ADDITIONS AND DELETIONS(EXCEPTIONS) OF API 551 SECTION 4

5.1 Scope

Modify

5.1.1 This section covers practices for the installation of instruments and devicescommonly used to indicate, record and control pressure and differential pressurenormally encountered in petroleum and petrochemical processes. Any deviationto this standard requires PDVSA approval. The instruments covered are pressuregauges and switches, pressure transmitters and locally mounted controllers andrecorders.

5.2 General

Numeral 4.2.4: Local Indication

Delete: “locally mounted pressure controls” in the first paragraph.




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PDVSA K–301


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Numeral 4.2.5: Vibration

Add the following statement: Adequate support shall be provided for all devicessharing a common process connection.

Numeral 4.2.8: Piping

Add the following statement to 4.2.8.1: Size and Design.

PDVSA requires, as a minimum, the use of 316 SS tubing for processconnections. Exceptions shall be approved by PDVSA.

Add the following statement to 4.2.8.2: Cleaning.

Pressure connections must include rodding facilities as required.

Numeral 4.2.10: Element and Socket (wetted) Materials

Add the following statement to 4.2.10: Element and Socket (wetted) Materials.

All wetted and pressure containing parts shall meet the piping class materialrequirements.

5.3 Pressure Gauges and Switches

Numeral 4.3.3: Safety Devices

Replace: “Gauges are available with safety glass or plastic windows as anadditional safeguard” with “Gauge windows shall be double–strengthshatter–resistant safety glass in high–pressure service”.

Numeral 4.3.5: Case Material and Size

Replace: “Plastic case” with “phenol case”.

Addition: The case shall be weatherproof, resistant to any specified corrosiveenvironment (marine, H2S, HF, HCL, etc.).

5.4 Pressure TransmittersNumeral 4.4.2: Installation Considerations

Replace: item c with “Placement of taps on the bottom of the line is not permitted”.

5.5 Section 6

Numeral 6.1: Scope

Addition: Any technique selected for protecting instruments from adverseprocess and ambient environments shall be agreed with PDVSA.

6 PDVSA SPECIFICATION FORMSRefer to ISA S 20.




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DEC.991

PDVSA K–301


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7 QUALITY ASSURANCE/QUALITY CONTROLRefer to PDVSA Specification K–369.




RECEIVER INSTRUMENTS

Item N° Tag. N° No. ofinputs

Notes:

20.1b

ScaleRanges

Service

PROJECT REFERENCEITEM N° QUANTITY

SPECIFICATION REFERENCES I.S.A SPDVSA–K–

N° By REVISED DATE

OFF SHEET OF

ChartRanges

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REVISION DATE


INSTRUCTIONS TO FILL FORMS20.1A AND 20.1B

Page 1

AUG.940

PDVSA 20.1

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RECEIVER INSTRUMENTS

a. To be used for a single item. Use secondary sheet for multiple listing.

b. Check as many as apply.

c. Nominal size refers to approximate front of case dimensions; width x height.

d. It is assumed that the instrument has its own case of shelf suitable for singlemounting, unless ‘‘MULTICASE” is checked. Shelf or separable case for multiplecase mounting instrument is not included unless listed and described as anaccessory.

e. Enclosure class refers to composite instrument. If electrical contacts are the casethey must meet this classification inherently or by reason of the enclosure. UseNEMA identification system or ISA System RP8.1.

f. Specify electrical power to the entire instrument from an external source.

g. For multiple instruments list ranges on secondary sheet, but specify other chartoptions on primary sheet. Chart graduations assumed to be uniform unlessotherwise noted. Circular charts assumed to have 24 hr/revolutions speed; stripcharts 3/4 in. to 1 in. per hour.

h. Chart drive mechanism assumed to be synchronous motor operating on 117V 60Hz and suitable for ENCLOSURE CLASS specified on line 5. If the chart drive ispneumatic so state – identify pneumatic pulser under options. Notes deviationsfrom standard (MFR) under notes i.e., dual speed or special speeds.

i. The scale type may be SEGMENTAL, VERTICAL, HORIZONTAL, DIAL(CIRCULAR) or other. Ranges 1, 2, 3 and 4 are used for multiple inputs. The firstlisted (N° 1) is assumed to be the controller input, if a controller is used.

j. See explanation of terminology given on specification sheet. For further definitionrefer to American National Standard C85.1–1963, ‘‘Terminology for AutomaticControl.’’ Specific ranges of control modes can be listed afetr ‘‘OTHER’’, ifrequired.

k. For multiple items specify on second sheet.

l. If standard auto–manual switching is not known or not adequate, specify particularrequeriments, such a BUMPLESS, PROCEDURELESS, 4–POSITION, or asrequired.

m. Remote set point adjustment assumes full adjustment range. Specify limits ifrequired. Under other can be noted bias or ratio.

n. Specify if applicable.

o. Specify if applicable.




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PDVSA 20.1

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p. All input signals on multi–channel instruments assumed to be the same unlessotherwise noted.

q. Specify number of inputs.

r. Check if power source for the loop is contained in this instrument or in someexternal instrument.

s. Form may be SPST, DPDT or other. Rating refers to electrical rating of switch orcontacts in amps.

t. Specify if alarm is actuated by measured variable or by deviation from controllerset point, Give contact action if single throw form.

u. Specify required accessories and options, fill in number of charts. This is assuredto be number of chart roles for strip charts.

v. After selection is made fill in manufacturer and specific model number.

SECONDARY SHEET – For listing multiple instruments. List all instruments of thesame type specified on the primary sheet, with variations an shown. “Notes refersto notes listed by number at the bottom of the sheet. Line 11 of sheet 1a istabulated under measurement increases, output tabulate increase or decrease.




PRESSURE INSTRUMENTS

Notes: 1. All items shall be corrosion resistant to marine atmosphere and tropicalised.

20.40a

Safe area

Yoke

Drive–Elec

Classified Class Group Div5. Enclosure

6. Power Supply

7. Chart Spring Speed

Other

Weatherproof Ex. Proof Intr. safe STD.

Temp. Class T1 T2 T3 T4 T5 T6


SPECIFICATION REFERENCES I.S.A SPDVSA–K–301

N° By REVISED DATE

OFF SHEET OF

GENERALRecord Indicate Control Trans Transducer

1. Tag N5 Service

2. Function

4. Mounting

110V 60Hz 24 Volts D.C Ext 20 P.S.I.G.

Circular Range

9. Scale Range 1 2 3

XMTR 10. Transmitter 4–20 mA 3–15 Psig Other

13. Set Point ADJ Manual Remote

14. Ouput 4–20 m.A. 3–15 Psig Other

Gauge Press Vacuum Absolute Compound15. Service

Diaphragm Helix Bourdon Bellows16. Type Other

316 SS Other Conn17. Material

Element Set at18. Range

Overrange Protection to

Fluid Max. Temp.Max. Press19. Process Data

Function on measurement Input

No of Alarms

High and Low20. Switches High Low

Rating 1 Amp. at 24 volts D.C. See Note 2

Fil. Reg Gauges Charts21.

Diaph. Seal cleanable type Diap. Matl. Body Matl.

Capillary Length Material

22. Model No

ELEMENT

ALARMS

OPTIONS

MFR

CONTR 11. Control Modes P PI Other Reversible Action

Manual Reg. Manual loading STN.

PID

Auto–man Switch

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Rev Tag N° Adj. Range Set Range Service Notes


NOTES:

S20.40b



N° By REVISED DATE

OFF SHEET OF

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REVISION DATE



Page 1

AUG.940

PDVSA 20–40ab

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1. To be used for a single item. Use secondary sheet for multiple listing.

2. Check as many as apply.

3. Nominal size refers to approximate front of case dimensions; width x height.

4. Yoke refers to a bracket designed for mounting the instrument on a pipe stand.

5. Enclosure class refers to composite instrument. If electrical contacts are in thecase, they must meet this classification inherently or by reason of theenclosure. Use NEMA identification or ISA identification per RP8.1.

6. Specify electrical power to the entire instrument from an external source.

7. Specify chart size, range and number if applicable.

8. Chart drive mechanism assumed to be synchronous motor operating in 117V60 Hz and suitable for ENCLOSURE CLASS specified on line 5. If the chartdrive is pneumatic so state – identify pneumatic pulser under options. Notedeviations from standard (MFR) under notes, i.e., dual speed or specialspeeds.

9. The scale type may be SEGMENTAL, VERTICAL, HORIZONTAL, DIAL(CIRCULAR) or other. Ranges 1, 2, 3 and 4 are used for multiple inputs. Thefirst listed (No. 1) is assumed to be the controller input, if a controller is used.

10. Specify transmitter output if applicable.

11. See explanation of terminology given on specification sheet. For furherdefinition refer to American National Standard C85.1–1963, ‘‘Terminology forAutomatic Control”. Specific ranges of control modes can be listed after‘‘OTHER’’ if required.

12. For multiple items specify on second sheet.

13. If standard auto–manual switching is not known or not adequate, specifyparticular requirements, such as BUMPLESS, PROCEDURELESS,4–POSITION, or as required.

14. Remote set point adjustment assumes full adjustment range. Specify limits ifrequired.

15. Specify if applicable.

16. Specify if applicable.

17. Specify pressure measurement application.

18. Specify type of pressure element.

19. Specify material of element.

20. If range is adjustable, specify range of adjustment and initial range setting.




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PDVSA 20–40ab

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21. Specify normal and maximum pressure.

22. Specify process connection size. If a diaphragm seal is used, connnection isspecified in line 26.

23. Form may be SPST, SPDT, DPDT, or other. Rating refers to electrical rating ofswitch or contacts in amps.

24. Specify if alarm is actuated by maesured variable or by deviation from controllerset point. Give contact action if single throw form.

25. Specify required accesories.

26. Use these lines to specify other options and accesories.

27. Fill in after selection is made.




PRESSURE GAGES

ITEM NO. TAG. N° RANGEOPERATINGPRESSURE SERVICE

NOTES:1. ALL ITEMS SHALL BE CORROSION RESISTANT TO MARINE ATMOSPHERE

20.41a

Material



N° By REVISED DATE

OFF SHEET OF

1. Type: Direct Rdg 3–15 lb Receiver

2. Mounting:

3. Dial:

4. Case: Cast Iron Aluminum Phenol

Other:

12. Element Mtl: Bronze SS

Other:

16. Diaphragm Seal

MFR

Fill Fluid

Type easily cleanable

Process Conn. Gage Conn. STD

Other:

Surface Local Flush

Diameter

5. Ring: Screwed Hinged Slip Std

6. Blow–out Protection: None Back Disc

Solid Front Other:

7. Lens: Glass Plastic

8. Options: Syphon

Pressure Limit Valve

Movement Damping

Snubber

9. Nominal Accuracy

10. MFR & Model No

11. Press. Element: Bourdon Bellow

Other:

Steel

13. Socket Mtl:

14. Connection–NPT:1/4 in Other:1/2 in.

Bottom Back

15. Movement: Bronze SS Nylon

Process Wetted Part Mtl. Other Mtl. STD

Bronze SSSteel

Other:

Other:

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N° By REVISED DATE

OFF SHEET OF

S20.41b

ITEM NO. TAG. N° RANGEOPERATINGPRESSURE SERVICE

NOTES:1. ALL ITEMS SHALL BE CORROSION RESISTANT TO MARINE ATMOSPHERE

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PDVSA 20.41a

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PRESSURE GAGES

a. When receiver gages are specified, the ‘‘Range’’ in the tabulation is the dial range.b. Select mounting style.c. Specify nominal dial diameter. Dial assumed white unless otherwise specified.d. Select case material.e. Specify ring style, or check ‘‘STD’’ if not important.f. Specify blow–out protection. ‘‘Back’’ refers to a blow–out back. ‘‘Disc’’ refers to a blow–out

disc located in the back or side of the case.g. Specify lens material.h. Options:

Snubber Specify type or model number.

Syphon If syphon required, specify material.

Material

Movement

Dampening Specify if required.

i. Specify nominal accuracy, such as ‘‘± 1/2%’’.j. Write in make and model number after selection is made.k. Specify element type or write in ‘‘MFR. STD’’.l. If stainless steel is required, write in the type; such as ‘‘316’’.m.See 12.n. Specify connection size and location.o. Specify movement or write in ‘‘MFR.STD’’.p. If Diaphragm Seal is required, fill in specifications.

For convenience, write in psig or other pressure unit at the top of ‘‘Range’’ and ‘‘OP.Press.’’ columns, if all are the same.




PRESSURE SWITCHES

REV. TAG. N° PROCESSCONDI-

TION

ADJ.RANGE

SET POINT OPERATINGSERVICE NOTES

NOTES:1. ALL ITEMS SHALL BE CORROSION RESISTANT TO MARINE ATMOSPHERE AND TROPICALISED.

20.42a

PRO-CESS

SIGNAL TEMP. PRESS.



N° By REVISED DATE

OFF SHEET OF

1. Type: Press Vacuum

Comp. Diff. Press

2. Setting:ype: Set in Field Factory Set

Internal External Dial

3. Dead Band: Fixed Adj. Min.

GENERAL

ELEMENT

4. Type: Diaphragm Bourdon Bellow.Other:

5. Material: Bronze SS Alloy Sr.

Other:

6. Connection: MFR STD

Bottom

Other: Size

7. Mounting: Local Surface Flush

8. Type: Snap

Other:

SWITCH

9. Quantity: Single Dual

10. Form SPST SPDT DPDT

11. Rating: Amps V Hz

Other:

12. Load: Non–Inductive

13. Enclosure:General Purpose Weatherproof

Intrinsically Safe System

Explosion Proof Class Group Div

14. Conduit Connection: 1/2” N.P.T.F.

Manufacturer & Model No

STD:

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PRESSURE SWITCHES

REV. TAG. N° PROCESSCONDITION

ADJ.RANGE

SET POINT OPERATINGSERVICE NOTES

20.42b

PROCESS SIGNAL TEMP. PRESS.



N° By REVISED DATE

OFF SHEET OF

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AUG.940

PDVSA 20.42a

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PRESSURE SWITCHES

a. Specify pressure, vacuum, compound, or differential pressure.b. Check setting in field or factory. Check internal or external setting adjustment. Check

whether calibrated setting dial is required.c. Specify fixed or adjustable dead band.d. Specify diaphragm, bourdon, bellow, or write MFR. STD.e. Select element material, for stainless fill in number, or write MFR. STD.f. specify conection size or write MFR. STD. Specify bottom or back connection.g. Specify mounting – Local (pipe) surface or flush.h. Check Mercury or Snap acting, or write MFR. STD.i. Specify number of switch in common housing.j. Specify switch form.k. Electrical rating in amps or watts, dc, or if, ac, give frequency in Hz.l. Check inductive or non–inductive load.m.Check one: general purpose, weather proof or explosion proof. Use NEMA identification.n. Check MFR. STD. or specify connection size.

TABULATION:

‘‘Process Conditions’’ refers to process condition which actuates switch such as‘‘High Level’’. ‘‘Adj Range’’ refers to limits within which a set point may beestablished, such as ‘‘1–18 #’’. If the pressure switch is in instrument air line, theset point may be specified in both process and signal units. ‘‘Notes’’ should beindicated by a number or letter and then explain in the space below the tabulation.




PRESSURE CONTROL VALVES PILOTS AND REGULATORS

ProcessData

BODY

TRIM

NOTES

Tag No

Non–Flashing Flashing Erosive Corrosive With solids

Service

Liquid


SPECIFICATION REFERENCES I.S.A S 75.01PDVSA–K–301

N° By REVISED DATE

OFF SHEET OF

Gas Steam

Units

Service conditions

Maximum Normal Minimum

C.V.

PSIAK

Pipe line Size–Inches INSULATION

Flow rateInlet pressure

TemperatureSpecific gravity or molecular WTViscosityCompressibility factorSpecific heat ratioCritical pressureFor flashing services only

IN

Class

dBNoise levelRequired ANSI/FCI Leakage

Max. Diff. pressure valve should withstand

C.V.

cPz

SCH OUT SCH

TypeSizeMfr & ModelBody/Bonnet MatlLinerEnd Conn.Flg Face Finish

Flow DirectionBonnetLub & Iso ValvePacking Material

Type of Actuator

Supply to PilotSelf Cont. Ext. Conn.Diaphragm Material

Filt. Reg. Supply GageLine StrainerHousing VentInternal Relief

Diaghragm RatingSpring RangeSet Point

ACTUATOR/PILOT161719202122242526272829

End Ext.

2021222324252627

282930313233

30

323334

TypeSizeCharacteristicSeats

Packing Type

1

2

13

353637

3940

19

Pc Vapour pressure% FlashCalculatedCalculatedFour

Gas C.V. Liquid C.VSelectedSelected

Five Six (Bubble Tight)

Plug/Ball/Disk Matl.Seat MaterialSoft seatCage/Guide Material

Rated

Stem Material

38

Yes No Matl.

Yes No Matl.

Yes No

ANSI Class

Rated Travel

1 2 Balanced UnbalCv FL XT

Yes No Matl.

ACCESORIES

20.51

In Out

MFR. Model No

1. All items shall be corrosion resistant to marine atmosphere

Pilot

Outlet pressure

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REVISION DATE

CATÁLOGO DE INGENIERÍA

INSTRUCTIONS TO FILL FORM 20.51

Page 1

AUG.940

PDVSA 20.51

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PRESSURE CONTROL VALVES – PILOT & REGULATORS

1–4. Identification and service or location. It is assumed that each tag numberis for a single valve.

5. Pressure reducing, back pressure control, or differential pressureregulator.

6. Globe, angle, or Manufacturer’s Standard (MFR.STD.).7. Body connection size and inner valve size.8. Guiding may be top, top and bottom, skirt, or MFR.STD. Select single or

double port, if applicable.9. Specify screwed (NPT), flanged, or weld end; and flange rating, such as

150 lb ANSI.10–11 Specify materials.

12. Write in ‘‘yes’’ or use check mark if required.

13. Quick open, equal percent, linear, etc.

State Characteristic:

L = LinearLV = Linear V PortEP = Equal PercentageEPT = Equal Percentage TurnedEPB = Equal Percentage BalancedQ = Quick Opening

Or use your own code and identify in notes.

14. Refers to seal between body and top works, such as diaphragm, stuffingbox, etc.

15. Refers to seat, plug, stem; in general, all internal wetted parts.16. Use only to specify soft seat, otherwise material will be same as trim

specified in line 14.17. Use if required.18. Max allowable sound level dBA 3 ft from pipe and 3 ft downstream of the

valve outlet.19. Actuator may be spring type or springless pressure balanced.20. The pilot is a integral or external auxiliary device which amplifies the force

available through an operating medium, usually air.21. Give pressure available and specify medium.22. Refers to valve pressure sensing system. Specify whether controlled

pressure is sensed internally or by means of an external line requiring anadditional piping connection.




REVISION DATE

CATÁLOGO DE INGENIERÍA

INSTRUCTIONS TO FILL FORM 20.51

Page 2

AUG.940

PDVSA 20.51

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23–24. Specify diaphragm material and pressure or temperature limits, ifapplicable.

25. Range over which pressure setting can be made.

26. Specification of set pressure does not apply to factory setting. This mustbe called for specifically, if required.

27. Specify filter regulator, with or without gage, if required for air supply topilot. Write ‘‘yes’’ or use check mark.

28. specify if strainer is to be furnished with valve. Write ‘‘yes’’ to check off;or give style or model number.

30–31. Options available in gas regulators. On line 30 specify‘‘bug–proof’’ ifrequired.

34. State liquid, steam, gas units gpm, lb/h/ft3/min. etc.

35. Name of fluid and state whether vapor or liquid if not apparent.

36. State maximum quantity required by process and corresponding Cv.

37. State operating quantity required by process and corresponding Cv.

38. The manufacturer shall fill in the valve Cv and FL (Liquid Pressure)Recovery Factor without reducers or other accesories.

39. Operating inlet pressure and pressure differential with units (psia, psig,inches H2O or Hg). Note at this point that one might consider howminimum conditions will fit the sizing.

40. Maximum inlet pressure if different from normal.

41. State the maximum pressure drop in shut–off position to determine properactuator size. This is actual difference in inlet and outlet pressure statedin psi, inches of H2O or Hg, etc.

42. State °F or °C.

43. State operating specific gravity and molecular weight.

44. State operating viscosity and its units. State flash at valve outlet, i.e., ofmax flow that will be flashed to vapor because of the valve pressure drop.

45. In the case of vapor, state superheat and in the cases of liquid, state thesolids, if present.

46. Note vapor pressure of fluid as well as the critical pressure.

47. Give manufacturers predicted sound level dBA.

48. Complete when available.




PDVSA k-301

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