icm du 5080 b temperature measurement criteria

ICM-DU-5080-B

TEMPERATURE MEASUREMENT CRITERIA

APPLICATION: ONSHORE

This document is the confidential property of Chevron U.S.A. Inc. Neither the whole nor any part of this document may be disclosed to any third party without the prior written consent of Chevron U.S.A. Inc. Neither the whole nor any part of this document may be reproduced, stoned in any retrieval system or transmitted in any form or by any means (electronic, mechanical, reprographic, recording or otherwise) without the prior written consent of Chevron U.S.A. Inc.

Rev Date Description Author Sponsor

A 10108 General Revision HONR RUE

B 10/09 Revision JAEF RUE

October 2009 © 2004-2009 Chevron U.S.A. Inc. All rights reserved. 1 of 17

Temperature Measurement Criteria ICM-0U-5080-B

CONTENTS

1.0 Scope ............................................................................................ ..............................4

2.0 References .................................................................................... ..............................4

2.1 ......Purchaser Documents ......................................................................................4 2.2 ...... Industry Codes and Standards .........................................................................4 2 .3 ...... Other Publications ............................................................................................5

3.0 Acronyms ...................................................................................... ..............................5

4.0 General Technical Requirements .............................................................................5

4 .1...... Data ..................................................................................................................5 4.2 ...... Electrical Area Classification ............................................................................5 4.3 ...... Safety Instrumented System Service ...............................................................6 4 .4 ...... Material .............................................................................................................6 4.5 ...... RFI Interference Protection ..............................................................................6 4 .6 ...... Quality Assurance ............................................................................................6

5.0 Thermowells ................................................................................. ..............................6

5.1...... General ......................................................................................................... •...6 5.2 ...... Material .........................................................................................:................. ..7 5.3 ...... Insertion Lengths ..............................................................................................8 5 .4 ...... Thermowells in Piping ......................................................................................8 5.5 ...... Flanged Thermowells .......................................................................................8 5.6...... Stress Analysis .................................................................................................a

6.0 Thermocouples ............................................................................ ..............................9

6 .1 ...... General ............................................................................................................. 9 6 .2 ...... Hot Junctions ..................................................................................................10 6.3 ...... Thermocouple Heads .....................................................................................10 6.4 ...... Wells and Thermocouples ..............................................................................11

7.0 Resistance Temperature Detectors ........................................... .............................11

7.1 ...... General .................................. •........................................................................11 7.2 ...... Insulation ........................................................................................................11 7.3 ...... RTD Heads .....................................................................................................12 7.4 ...... Wells and RTDs .............................................................................................12 7.5 ...... Applications ....................................................................................................12

8.0 Temperature Transmitters .......................................................... .............................12

8 .1 ...... General ...........................................................................................................12 8 .2 ......Input Types .....................................................................................................13 8.3 ...... Mounting of Transmitters ................................................................................13 8.4 ...... Saline Environments ......................................................................................14 8.5 ...... Non-Corrosive Environments .........................................................................14


Temperature Measurement Criteria ICM-DU-5080-B

9.0 Indicating Thermometers ........................................................... .............................15

9 .1 ...... General ........................................................ .............................•• ........15 9.2 ......Bimetallic Thermometers ................................................... .............................15 9 .3 ...... Remote Indicators ............................................................. .............................15 9 .4 ...... Local Indicators ................................................................. .............................16

10.0 Filled and Mechanical Thermal Systems .................................. .............................16

11.0 Dial Thermometers ...................................................................... .............................16

12.0 Temperature Alarms and Shutdowns ....................................... .............................17

13.0 Installation Requirements .......................................................... .............................17

14.0 Nameplate and Tagging .............................................................. .............................17

15.0 Preparation for Shipment ........................................................... .............................17



1.0 SCOPE

1. Temperature instruments measure, indicate, and control the temperature of process equipment and systems.

2. This specification covers the minimum technical requirements for the design, purchase, and testing of temperature instruments to be installed at Purchaser downstream facilities.

3. This specification shall be used in conjunction with project technical requirements and data sheets for each instrument.

4. More specific and comprehensive criteria may need to be developed for particular project needs.

2.0 REFERENCES

1. The following documents are referenced herein and are considered part of this specification.

2. Use the latest edition of each document referenced below unless otherwise specified.

3. If conflicting statements exist within this document or between this document and the documents or drawings referenced, Supplier shall bring these to the attention of Owner for resolution.

2.1 Purchaser Documents

ICM-DG-5129 Data Guide for Temperature Instrument Data Sheets

ICM-DS-5129 Data Sheets for Temperature Instruments

G13-J1195 Instrument Installation Detail — 3/4" Screwed Thermowell

GB-J1196 Instrument Installation Details — Screwed Thermowell Installation in Piping

GB-J1197 Van Stone Thermowell Details for NPS —1 1/2" and 2" Flanged Connections

GB-J1198 Instrument Installation Details — Flanged Thermowell Installation in Piping

GB-J1200 Fabrication Detail — Thermowell for Furnace Stack

GB-J 1202 Instrument Installation Details — Reactor Skin Point Thermocouple

G1341203 Fabrication Details — Reactor Skin Point Thermocouple Assembly Details

GD-J1201 Installation for Furnace Tube Skin Point Thermocouple (SPTC)

2.2 Industry Codes and Standards

American Society of Mechanical Engineers (ASME)

PTC 19.3 Part 3= Temperature Measurement Instruments and Apparatus

American Society for Testing and Materials (ASTM)

A276 Standard Specification for Stainless Steel Bars and Shapes

A479 Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels

E1137 Standard Specification for Industrial Platinum Resistance Thermometers

Compressed Gas Association (CGA)

G4.4 Oxygen Pipeline Systems (EIGA Doc 13102)


Temperature Measurement Criteria

1CM-DU-5080-13

International Electrotechnical Commission (1EC)

60529+A1 Degrees of Protection Provided by Enclosures

60584-2 Thermocouples_ Part 2: Tolerances

60751 Industrial Platinum Resistance Thermometers and Platinum Temperature Sensors

international Society of Automation (ISA)

MC96.1 Temperature Measurement Thermocouples

National Association of Corrosion Engineers (MACE)

MR0103 Materials Resistant to Sulfide Stress Cracking in Corrosive Petroleum Refining Environments – Item No. 21305

2.3 Other Publications

Naval Post Graduate School, Monterey, California

NPS-59BC74112A Stress Analysis of nermowells (Unclassified), J. E. Brock, I 1 Nov 1974.

3.0 ACRONYMS

FF—Foundation Fieldbus

NPT—National Pipe Thread

PCS—Process Control System

RFI--Radio Frequency Interference

RTD—Resistance Temperature Detector

SIS--Safety Instrumented System

SPl—Smart Plant Instrumentation

SS—Stainless Steel

4.0 GENERAL TECHNICAL REQUIREMENTS

4.1 Data

1. A data sheet shall be provided for each temperature instrument.

2. Data sheets shall be in electronic or hard-copy format.

a. Smart Plant Instrumentation (SPI) is the preferred application to generate electronic data sheets.

b. Templates included in ICM-DS-5129 shall be used to generate hard-copy data sheets.

3. Instructions in ICM-DG-5129 shall be followed for filling out temperature instrument data sheets.

4.2 Electrical Area Classification

Temperature instruments shall be specified to meet project requirements for electrical area classification.

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4.3 Safety Instrumented System Service

1. Temperature instruments used in Safety Instrumented System (SIS) applications shall do the following:

a. Use separate temperature sensors and thermowells for process control system (PCS) and SIS services where practical.

b. Utilize only highly reliable sensing technologies.

c. Fail in the safe direction.

d. Be designed and installed to support regular on-line testing to verify accuracy and correct operation_

e. Comply with requirements of the applicable specification(s) pertaining to SIS.

2. Written acceptance by Purchaser is required in order to use duplex thermocouples/resistance temperature detectors (RTDs) sharing the same thermowell for both PCS and SIS applications.

4.4 Material

1. Instrument wetted parts shall be compatible with the process fluids.

2. Temperature instrument wetted parts shall be 316 stainless steel (SS) or better unless the process requires a special material per project piping specifications.

3. Wetted O-ring material selection shall be based on the nature of the process monitored.

a. 0-rings constructed of Teflon or Viton shall be used in hydrocarbon applications.

b. 0-rings constructed of Buna-N shall not be used in hydrocarbon applications.

4. Instruments exposed to sour process streams shall conform to NACE specification MR0103.

4.5 RFI Interference Protection

Radio frequency interference (RFI) protection for electronics shall be as follows: in a 10 voltmeter field strength with frequencies of 20 to 500 MHz, output signal from instrument under test shall have maximum variation of 0.5 percent of span.

4.6 Quality Assurance

Quality assurance provisions shall be in accordance with the project technical requirements.

5.0 THERMOWELLS

5.1 General

1. Thermowells shall be provided for temperature-measuring devices such as thermocouples, RTDs, and indicating thermometers.

2. Temperature sensors in atmospheric and non-hazardous services may be installed without a thermowell. Examples of such services are ambient air, motor windings, bearing temperatures, electronic equipment cabinets, furnace tubeskin points, and reactor multipoint temperature bundles.

3. Standard thermowell bore sizes shall be 0.26 inch (6.6 mm) and 0.385 inch (9.8 mm).

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ICM-DU-5080-B

4. Locations that require only occasional temperature measurements to check equipment (i.e., continuous measurement is not required) shall have test thermowells with the following.

a. An internal bore diameter of 0.385 inch (9.8 mm)

b. A 316 SS plug and chain

5. Thermowells installed in oxygen service shall meet the requirements of CGA G-4.4 and the engineering standards of the oxygen producer. (Refer to Article 4.3, "Velocity," of CGA G-4.4 for requirements.)

6. Thermowells shall be specified with their accompanying instrument so that the devices are dimensionally compatible.

7. Unless temperature limitations require ceramic or other material, thermowells in fired heater walls, ducts, and stacks shall be of type 310 SS, in accordance with ASTM A276.

8. Refer to GB-J1200 for furnace stack thermowell fabrication details.

9. If two independent readings of a temperature are necessary, a second temperature element located in a separate thermowell shall be provided.

10. Thermowells shall not be installed in the upstream and downstream straight runs of flow meters.

11. Purpose-designed multiple cluster thermocouple assemblies shall be used where reactor vessels containing fixed, packed catalyst beds are used and multiple temperature measurements are required, either in the vertical plane to monitor catalyst activity, or in the horizontal plane to detect channel flow.

a. Thermocouple assemblies shall be provided with specially fabricated thermowells of suitable length and inside diameter, which meet the vessel code requirements for material, wall thickness, and mounting connection.

b. The design shall be reviewed and accepted by Purchaser_

12. Thermowells shall be designed to be suitable for the service in which they are used.

a. For general service, drawings GB41195, GB-J1196, GB-Jl 197, GB-Jl 198, and GB-J1200 shall be considered as the minimum acceptable practice for thermowell selection.

b. For corrosive or erosive services, the use of alternative materials and construction shall be considered, subject to Owner's acceptance.

13. Temperature test points (thermowells) shall be provided so that test and performance data may be obtained, though the cost of permanent instrumentation is not justified.

14. Plating shall not be allowed unless reviewed and accepted by Owner for special applications.

5.2 Material

1. The minimum acceptable material for thermowells is 316L stainless steel for temperatures up to 1004°F (540°C) and 321L for higher temperatures.

2. Any other material required for special applications (e.g., reactors) shall be identified on the instrument data sheet.

3. Material shall be as per ASTM A479 Gr F316/321L and A479 Gr 316/321L.

4. Thermowells shall be manufactured from solid bore drilled material.


Temperature Measurement Criteria ICM-0U-5880-B

5.3 Insertion Lengths

1. Thermowell insertion length shall be 9 inches (228.6 mm) unless thermowell stress analysis requires a different insertion length.

2. A thermowell installed perpendicular to or at a 45-degree angle to the pipe shall have a minimum immersion length of 2 inches (50.8 mm) and a maximum distance of 5 inches (127 mm) from the inner wall of the pipe. If the thermowell is installed at an angle or in an elbow, the tip shall point to the flow in the process line.

3. Thermowells mounted in horizontal vessels shall have an insertion length of least 9 inches (228.6 mm) up to a maximum of 12 inches (304.8 mm).

a. Insertion length shall not exceed one-half the vessel diameter_

b. Exception: special situations such as agitated vessels may require shorter thermowell installations.

4. Insertion length of fired heater thermowells in fire boxes shall ensure that the end of the thermowell is not shielded from flame by tubes, bricks, etc., inside the heater.

5.4 Thermowells in Piping

1. Thermowells in piping shall be located as close as is practical to the point in the process at which the temperature is required.

2. Thermowell process connections shall be in accordance with the project piping specification.

3. Thermowells installed in insulated piping shall be specified with a 3-inch (76-mm) or 6-inch (152-mm) lagging extension, whichever is applicable.

5.5 Flanged Thermowells

1. Van Stone thermowells may be used for flanged thermowell process connections. Refer to GB-71197 for Van Stone thermowell design detail.

2. Use of slip-on flanged thermowells shall not be allowed.

5.6 Stress Analysis

1. Thermowell stress analysis shall be performed to avoid vibrations induced by the Von Karman vortex frequency, which may cause noise and possible failure of thermowells due to metal fatigue.

2. In high velocity streams, thermowells shall be of tapered stem design so that the thermowell natural frequency is at least 1.25 times greater than the Von Karman vortex frequency.

3. Each thermowell shall be provided with its vibration calculation (Strouhall or Von Karman trail).

4. The stress calculation and thermowell design for such applications shall be subject to Purchaser's review and acceptance.

a. if fluid Reynolds Number is less than 40,000, either ASME PTC 19.3 or the method described below may be used when performing thermowell stress analysis.

b. If fluid Reynolds Number is greater than 40,000, thermowell stress analysis shall be calculated using the method described below.

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ICM-0U-5080-B

Step 1: Determine the Stroubal Number (Ns):

For NR < 40,000: use Ns = 0.21

For 40,000 < N R < 400,000: use Ns = 0.24 (log 10 NR) - 0.894

For NR > 400,000: use Ns = 0.45

where:

NR = Reynolds Number

Ns = Strouhal Number

Step 2: Calculate the vortex frequency (f„ Hertz) as follows:

f„ = 12 Ns U/dt

where:

f, = Vortex frequency

U = Fluid velocity (feet/second)

d, = Thermowell diameter at the end (inches)

Step 3: Calculate the lowest natural elementary frequency (Q of the thermowell:

f,, = (Rf)(Ff)(d,,1L') EI(r +r)

where:

R f = Frequency response factor = [I - 0.4(d,+dj/L]

Ff = Frequency factor = [ 1.65+ 1.21(d,/d,)(1.0 - 0.094 d, Q]

dr = Outside root diameter of thermowell (inches)

L = Length of thermowell, root to tip (inches)

E = Young's modulus (28.6 x 106 for stainless steel)

Y = Specific weight of well material (lb./inch')

y'= Specific weight of fluid (lb./inch')

6.0 THERMOCOUPLES

6.1 General

I . Thermocouple properties, extension wires, color coding, and limits of error shall conform to 1EC 60584-2/ANSI ISA MC96.1, Class 1.

2. Thermocouples shall be prefabricated and swaged, with the following specifications:

a_ 18-gauge wire (minimum).

b. Hard-packed magnesium oxide insulation.

c. Metal-sheathed 1/4-inch (6.35-mm) OD 316 SS seamless tube with welded closed ends.

d. Ceramic potted extension wire exit from sheath.

3. Thermocouple pigtail wires shall be 22-gauge wire (minimum).



4. Thermocouple metal sheath shall be connected to the ground connection terminal strip in the thermocouple/transmitter head via the extension wire shield in the sealed transition piece; crimped connections are not acceptable.

5. The shields of both grounded and ungrounded thermocouples shall be grounded on the thermowell side; shields shall be grounded at only one point.

G. Thermocouples shall be duplex elements, except for fired heater applications, where single- element type N shall be used.

7. Duplex thermocouples shall be ungrounded and isolated (hot junctions not welded together).

8. Type E (Chrome]-Constantan) thermocouples shall be used in temperature ranges from —3280 to 32°F (-20011 to 0°C).

9. Type K (Chromel-Alumel) thermocouples shall be used in temperature ranges from 32° to 2300°F (00 to 1250°C).

10. Thermocouples installed in thermowells shall be spring-loaded type.

11. Thermocouples shall not be connected to more than one device.

12. Refer to GB-J 1203 for reactor skin point thermocouple fabrication detail.

6.2 Hot Junctions

1. Thermocouples with ungrounded hot junctions may be connected together for differential or averaging temperature measurement applications.

a. Individual thermocouples connected to isolated transmitters, however, are preferred.

b. Ungrounded sheathed thermocouples shall have a resistance of greater than 10 mega ohms at ambient temperature between the sheath and the thermocouples to ensure proper insulation.

2. Thermocouple hot junction shall be x-rayed to assure its uniformity (at least 10 percent of the batch and 100 percent for critical applications as defined by Purchaser).

3. When thermocouples with grounded hot junctions are used, the thermocouple head shall have an internal ground connection screw for the screen of the extension wire to be grounded.

a. Thermocouples shall have a grounded hot junction and high purity magnesium oxide insulation.

b. Thermocouples with grounded hot junctions shall be used only with Purchaser's acceptance.

4. Insulated hot junctions shall have an insulation resistance to ground of 50 mega ohms minimum at ambient temperature and 2 mega ohms minimum at 850°F (450°C).

6.3 Thermocouple Heads

1. Thermocouple heads shall have the following features:

a. Compression-type terminal block with brass terminals.

b. An extra terminal for attaching the extension wire shield connection (duplex thermocouples require six terminals).

c. Two internally threaded conduit connections.

2. Cast aluminum may be used for the thermocouple bead if the instrument is to be located in an environment that is not corrosive to aluminum.



ICM-DU-5080-B

3. 316 SS or Owner-accepted alternative shall be used for the thermocouple head if the instrument is to be located in an environment that is corrosive to aluminum.

4. Thermocouple wires within the termination head shall be installed with color coded PTFE sleeves to indicate the positive/negative, in accordance with ANSI ISA MC96.1.

6.4 Wells and Thermocouples

1_ Wells and thermocouples shall be provided preferably as matched units.

2. Thermowell dimensions shall result in good contact between the thermocouple and the well.

3. Larger epoxy-coated cast iron heads with sufficient terminal blocks for vendor to terminate both elements' wires shall be used.

4. Stainless steel chain shall be included.

5. Terminals within the head shall be clearly marked "+," "—," "ground," as appropriate.

6. Multi circuits within heads shall be clearly identified.

7. For further details of the thermocouple assembly, refer to drawing G1341203.

7.0 RESISTANCE TEMPERATURE DETECTORS

7.1 General

1. RTDs shall use a 100-ohm platinum (99.999 percent purity) element (resistance measured at 0°C) wound on a ceramic or glass core, hermetically sealed, and manufactured in accordance with EEC 60751, Class B.

2. RTDs shall be 3-wire ungrounded, 100 ohm at 0°C complete with thermowell, large cast iron .head, union, and terminal blocks for dual RTD termination.

3. For special high-accuracy applications; 4-wire RTDs shall be acceptable.

4. Platinum RTDs shall use one of the following standards for temperature coefficient:

a. Temperature coefficient of 0.00385°C-1 per IEC 60751, or

b. Temperature coefficient of 0.0039083°C-1 per ASTM E1137.

5. RTDs shall be enclosed in a 1/4-inch (6.3-mm) OD 316 SS (seamless tube with welded close ends) protection sheath (minimum), with an epoxy or ceramic sealed transition piece and 22 AWG minimum copper lead wires.

7.2 Insulation

1. RTDs shall use insulated nickel or nickel alloy wire from the platinum element to the epoxy or ceramic sealed transition piece where the copper wires shall be attached by welding or soldering. Crimped connections are not acceptable.

2. RTDs shall be fabricated with 18 AWG (minimum), in hard packed magnesium oxide insulation.

3. RTD lead wire insulation shall be color coded per IEC 60751.

4. Insulation resistance to ground shall be 50 mega ohms minimum at ambient temperature, and at least 2 mega ohms minimum at 450°C (850°F).



7.3 RTD Heads

RTD heads shall have the following features:

1. Cast aluminum construction if the instrument is to be located in an environment that is not corrosive to aluminum.

2. 316 SS construction (or Owner-accepted alternative) if the instrument is to be located in an environment that is corrosive to aluminum_

3. Compression-type terminal block with brass terminals with an extra screw provided for attaching the extension wire shield (duplex RTDs require 6 or S terminals).

4. Two internally threaded conduit connections.

5. Terminals within the head identified with wires color-coded in accordance with the local specifications or IEC 60751.

7.4 Wells and RTDs

1. Wells and RTDs shall be provided as thatched units.

2. Thertnowell dimensions shall result in good contact between the RTD and the well.

3. RTDs installed in thertnowells shall be spring-loaded type.

7.5 Applications

1. For measured temperatures below 1100°F (600°C), RTDs manufactured in accordance with IEC 60751 (or ASTM E1137) shall be used in the following cases:

a. In temperature measurement for calculations in which a thermocouple would not provide sufficient accuracy.

b. In control applications requiring high accuracy and repeatability, where the thermocouple voltage span would be less than 5 mV.

c. In differential temperature measurements of less than 5 mV or 115°F (50°C), in which case matched pairs shall be used.

2. RTDs shall be used on motor applications.

3. RTDs shall not be installed where excessive vibration exists.

8.0 TEMPERATURE TRANSMITTERS

8.1 General

1. Temperature transmitters shall have the following characteristics:

a_ A minimum accuracy, including the combined effects of linearity, hysteresis, and repeatability, of f 0.25 percent of the calibrated span.

b. A configurable input type (thermocouple or RTD) and span.

2. Transmitter output shall use 4-20 mA HART or Foundation Fieldbus (FF) signals.

3. LCD digital-type displays shall be preferred for indication.

4. Transmitter housing shall provide ingress protection (IP) equivalent to National Electronics Manufacturers Association (NEMA) 4X or EP 65 as defined in IEC 605529+A1.

5. Only one temperature measuring device shall be connected to a temperature element.


Temperature Measurement Criteria ICM-DU-5080-8

6. If the process temperature is required to be monitored by more than one device, one of the following shall be done:

a. It shall be converted using an electronic transmitter, or

b. Separate measuring elements and cabling shall be installed.

7. Temperature control loops shall have a temperature transmitter.

a. Standard input to the temperature transmitter shall be a 100-ohm platinum RTD, as described in Section 7.1.

b. RTDs shall be 3-wire ungrounded.

8. Burnout protection circuits shall be provided for remote temperature measurements.

9. Burnout direction shall be selected to reduce any hazard and an alarm shall be initiated.

10. Field-mounted temperature transmitters with integral indicators shall be used for temperature controllers and critical temperature measurements.

8.2 Input Types

1. Temperature transmitters shall be electronic and of smart-type design with an input from a thermocouple or RTD sensor.

2. Transmitters having a thermocouple input shall also provide the following:

a. Input/output isolation.

b. Cold junction compensation.

c. Automatic thermocouple burnout detection with selectable upscale or downscale failure mode.

d. Configurable transmitter burnout.

e. Built-in temperature linearization capability for output signal.

3. Transmitters having RTD input shall also provide the following:

a. Input/output isolation.

b. A dedicated screw connection for use in grounding the RTD extension wiring shield.

4. Multi-input temperature transmitters shall not be used for control applications (indication only).

8.3 Mounting of Transmitters

Temperature transmitters shall be mounted as follows:

1. On the thermowell, provided the head temperature is less than 160°F (70°C).

2. On stand (not close-coupled to element).

3. Remotely from the thermowell if the head temperature is 160°F (70°C) or greater, or where access is difficult.

4. As close as to the element as is practical.



8.4 Saline Environments

1. Temperature transmitters used in a facility near a large body of salt water shall utilize 316 SS electrical housing material and 316 SS support bracket and support bolts.

2. Connections to transmitter housing shall meet the following requirements:

a. If cables are used, cable terminators and glands shall be either brass or 316 SS, and entry threads shall be nickel-plated brass or 316 SS.

b. If conduit is present, an approved method of connecting the conduit to the instrument housing shall be used (Approved method generally utilizes a union and metal-clad cable or flexible conduit between the rigid conduit and the instrument housing.)

c. If PVC-coated steel conduit is used, a urethane touch-up coating shall be applied to Feld cuts and internal reams to prevent corrosion.

d. Threads (electrical connections and access caps on both ends of the transmitter housing) shall be coated with an approved thread lubricant, such as Thomas & Betts Kopr-ShieidTm, to prevent corrosion.

Caution Instrument housings with a "Flameproof" or "EEx d" rating require the use of a non-setting lubricant, per IEC-60079-14. Fuchs Lubritech PBC BA200 is approved by the British Approval Service for Electrical Equipment in Flammable Atmosphere (BASEEFA) for use in this type of application.

3. Unused electrical ports shall be plugged with 316 SS threaded plugs.

4. Use of aluminum instrument housings in saline environments shall require written acceptance from Owner.

a. Instrument housing shall be constructed of a marine grade aluminum alloy containing less than 0.1 percent copper.

b. Instrument shall be located inside a panel or other enclosure, sheltered from the elements and wash-down spray. Enclosure shall be equipped with drain.

c. If instrument cannot be located inside a panel or other enclosure, instrument housing shall be painted with a base coat of epoxy resin and a second coat of polyurethane resin, with the total thickness of coatings not less than 100 microns.

5. A heat-shrink wrap shall be installed around the entire transmitter electrical connection, including the cable gland.

8.5 Non-Corrosive Environments

1. If the instrument is to be located in an environment that is not corrosive to aluminum, transmitter housing shall be Supplier's standard cast aluminum.

2. Support bracket and support bolts shall be compatible with aluminum and provide corrosion resistance.

3. Plated materials shall not be used.

a



9.0 INDICATING THERMOMETERS

9.1 General

1. Indicating thermometers shall be heavy-duty bimetallic sealed-type.

2. Indicating thermometers shall have a minimum accuracy of f 1.0 percent of the scale span.

3. Indicating thermometers shall be designed to install into a thermowell with a 0.10 inch (2.5 mm) clearance between the thermometer stem and the inside diameter of the thermowell.

4. The stem length 'of thermometers shall be selected to bottom out in the thermowell in which they are to be installed.

5. Thermometers shall be furnished with thermowells.

6. The use of mercury-in-steel thermometers may be considered only when an accuracy better than 1 percent span is required, and shall require Owner's review and acceptance.

7. The normal operating temperature shall be within the middle third of the scale.

9.2 Bimetallic Thermometers

Bimetallic thermometers shall have the following features:

1. Single or multiple helix measuring element contained in a dampening fluid.

2. Minimum 5-inch (127-mm) diameter dial face with a non-glare white finish and black or contrasting color markings.

3. 316 SS weatherproof case with bezel ring for temperatures up to 1020°F (550°C).

4. One-quarter inch (6.35-mm) OD protection tube.

5. Hexagonal head or wrench flats.

6. Adjustable, heavy-duty, every-angle-type construction.

9.3 Remote Indicators

Remote temperature indication in the central control room shall be shown on the P&IDs and, as a minimum, shall be provided at locations given in Table 1 _

Table 1: Remote Temperature Indicator Locations

Columns Inlet and outlet process lines.

Vessels Inlet and outlet lines where different temperatures are expected.

Heat Exchangers On inlet and outlet of both sheik and tubesides for each exchanger bank, to give both direct and differential temperatures.

Heaters On process inlet and outlet, as a minimum. In each pass as required by the heater design. Furnace floor when Low NOx bumers are used.

Blowers/Compressors Inlet and outlet of casings and interstage connections.

Process Streams Downstream of interconnections of important streams.

Air Coolers Product inlet and outlet streams.

Flow Meters At flow transmitters where temperature correction of flow is required.



9.4 Local Indicators

Local indicators shall be provided at the following locations and shown on the F&ID:

1. Outlet water streams from condensers and coolers.

2. Discharge of blowers and compressor casings.

3. Lube oil and cooling water circulation systems for equipment such as pumps, turbines, and compressors.

4. Storage tanks.

10.0 FILLED AND MECHANICAL THERMAL SYSTEMS

1. Filled thermal element transmitters and controllers are not recommended.

2. Filled thermal system-type thermometers may be used only in remote locations or in extreme process temperature ranges, and shall have Owner's written acceptance.

3. The use of direct-actuated (e.g., capillary or bimetal) temperature switches shall require Owner's written acceptance_

4. The use of self-actuated temperature regulators shall require Owner's written acceptance.

5. Thermal systems for local pneumatic transmitters shall have the following:

a. Dimensions of approximately 318 inch (10 mm) OD bulb of 5 inches (125 mm) maximum length.

b. A capillary of PVC-covered armored stainless steel, not greater than 6 feet (2 m) in length.

c. A minimum flexible extension length of 1.5 feet (500 mm).

6. Thermal systems for direct-connected instruments shall have the following:

a. A maximum length of 18 feet (6 m) of armored capillary.

b. A 112-inch NPT male stainless steel compression fitting, to enable the bulb to be fully inserted and fastened into the 112-inch NPT female connection on the well.

11.0 DIAL THERMOMETERS

1. Dial thermometers shall be bimetallic, heavy duty, every-angle-type with 5-inch (125-mm) diameter anti-parallax dials and manufacturer's standard weatherproof case.

2. Ranges shall be standardized to the extent practical, and selected to ensure that the normal process operating temperature falls as near as possible to midpoint of range.

3. The stem shall be 114-inch (6.35-mm) OD Type 310 stainless steel with a 112-inch (I2.7-mm) NPT male connection.

4. Stem lengths shall be to the manufacturer's standard.

5. Identification of thermometer shall be a wired-on tag of stainless steel showing tag number.

6. If a local bimetallic temperature indicator is appropriately positioned, then a separate local electronic indicator shall not be required.



12.0 TEMPERATURE ALARMS AND SHUTDOWNS

1. High-temperature alarms and shutdowns shall be required on the discharge of compressors.

a_ Because temperatures may rise rapidly, thermocouple or RTD-type sensors shall be used.

b. Filled thermal systems shall not be used.

2. Temperature alarms shall be derived from transmitter signals.(4-20 ma HART or FF) and not from field-mounted switches.

13.0 INSTALLATION REQUIREMENTS

1. When temperature measurement is required following the combining of two or more streams (such as at the outlet of a multipass heater), the thermowell measuring the combined temperature shall be located as follows:

a. In liquid service—a minimum of 10 pipe diameters downstream of the junction.

b. In gas or vapor service—a minimum of 30 pipe diameters downstream of the junction.

2. Thermowell installation shall be per the project piping specification.

3. Refer to GB-J1202 for reactor skin point thermocouple installations.

4. Refer to GD-J 1201 for heater/furnace tube skin thermocouple installations.

14.0 NAMEPLATE AND TAGGING

1. Each piece of a temperature instrument assembly shall be either stamped or provided with a permanently attached stainless steel tag engraved with tag numbers 114 inch (6.4 mm) high.

2. Thermocouples shall also be stamped with ANSI ISA MC96.1 designation.

3. Thermowells shall have the following information stamped on the side of the flange:

a. Material

b. Nominal "V' dimension

c. Heat number (for traceability as per ISO)

d. Tag number

e. Size

f. Rating

15.0 PREPARATION FOR SHIPMENT

1. Flange faces shall be protected by solid covers.

2. Threaded connections shall have thread protectors.

3. End connections shall be covered to exclude dirt.

4. Temperature instrument assembly shall be shipped flat in a container with waterproof paper or plastic liner; openings in the liner shall be taped shut.

5. Indicating thermometer gauge movements shall be blocked to avoid excessive vibration.

6. The shipment shall be clearly marked on at least two sides with the following information:

a. Purchaser order number, name, and shipping address

b. Manufacturer

7. A transmittal document shall be accessible without opening the shipment and shall clearly identify the number of instruments with the model number(s) and instrument tag number(s).

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