TANK GAUGING AND ALARM SYSTEMS

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 1 of 19

TABLE OF CONTENTS 1.0

SCOPE

2.0

REFERENCES

3.0

DEFINITIONS

4.0

GENERAL

5.0

LEVEL GAUGING SYSTEMS

6.0

ALARMS AND SHUTDOWNS

1

04/23/97

0B

01/16/97

Approved for Construction Revised Para. 4.3 Approved for Design With Yanpet Comment

0A

09/11/96

0

08/13/96

Rev

Date

GRS

RCD

SNP

04/28/97

JM

04/28/97

RNS

RCD

SNP

01/16/97

JM

01/17/97

Approved for Design

GRS

RCD

SNP

09/18/96

JM

09/18/96

For client approval

GRS

RCD

SNP

08/13/96

Orig

Ckd By

Description

Approved By

Client Approval

SAUDI YANBU PETROCHEMICAL COMPANY YANPET EXPANSION PROJECT SPECIFICATION FOR AUTOMATIC TANK GAUGING SYSTEM AND LEVEL ALARMS

Document1

SPECIFICATION NO:

REV:

2J-010

1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

1.0

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 2 of 19

SCOPE This specification defines the minimum requirements for automatic gauging systems and level alarm and shutdown requirements on product storage tanks on the Saudi Yanbu Petrochemical Company Expansion Project. This specification shall be used in conjunction with instrument data sheets provided with the purchase documents. Any deviation proposed by the Seller must be resolved and a clarification obtained in writing from the Buyer before any work is done.

2.0

REFERENCES The following publications form a part of this Specification. Unless otherwise specified herein, use the latest edition. 2.1

Project Specifications A-010

General Specifications for Sellers A-011 Shop Preparation of Equipment & Material for Shipment and Storage

2.2

2J-013

Alarm and Signal Handling

2J-016

Instrumentation - Temperature

API (American Petroleum Institute) Publications MPMS 3.1B Standard Practice for Level Measurement of Liquid Hydrocarbons in Stationary Tanks by Automatic Tank Gauging MPMS 7.4 Static Temperature Determination Using Fixed Automatic Tank Thermometers RP 2350

Overfill Protection for Petroleum Storage Tanks STD 2540 Manual of Petroleum Measurement Standards, Chapter 11, Section 1

2.3

NFPA (National Fire Protection Association) Code 30 70

Document1

Flammable and Combustible Liquids Code National Electrical Code

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

3.0

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 3 of 19

DEFINITIONS Unattended Area: One that is continuous observation for 24 hours per day.

not

under

Class I (Flammable) Liquid: A liquid having a flash point below 37.8°C. High Level Alarm: Level alarm, set above the normal fill level of liquid in a tank. High/High Level Alarm: Level alarm, set above the high level alarm point, that shall allow sufficient time for an orderly shutoff or diversion of liquid before the tank overflows. 4.0

GENERAL 4.1 Vessels and tanks utilized for product storage and filled from pipeline or marine vessel shall be provided with Automatic Tank Gauging (ATG) systems and level alarm systems as defined in this specification and referenced standards, codes, and project specifications. The specification shall be applied as follows: a. Product storage tanks, except cryogenic, shall be equipped with a Hydrostatic Tank Gage (HTG) system for liquid level measurement b. Cryogenic product storage tanks shall be equipped with a servo-operated automatic tank gauging system which minimizes tank wall penetrations (i.e. tank top connection only). c. Tanks and vessels that are used for storage of Class 1 liquids shall be equipped with a high level alarm. Also, vessels in this type of service in unattended areas shall be equipped with a high-high level shutdown system. Level alarms and shutdowns shall be independent of the automatic gauging system. 4.2 Components and systems shall meet applicable national, state, and local code requirements for their intended use.

1

4.3 All devices shall be certified as being suitable for a nonincendive circuit in accordance with NEC and ISA S12.12. Specifically the surface temperature of any component shall not exceed 160 deg C based on an ambient temperature of 50 deg C. If such certification is not available then they shall be certified as explosion proof and installed in conformance with NEC requirements for explosion proof devices. In addition they shall meet the parameter requirements of ISA 12.12 with respect to their use in a nonincendive circuit.

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 4 of 19

4.4 Electrical equipment and circuits for instrumentation and controls shall be certified for the electrical area classification in which they are to be installed, in accordance with National Electrical Code (USA), NFPA-70. 4.5 Electrical or electronic instruments or devices for use in hazardous areas shall be approved for the installation location by a nationally recognized authority. Examples are Underwriters Laboratories (UL), Factory Mutual (FM), the Canadian Standards Association (CSA) in North America, and (BASEEFA) in Europe. 4.6 The field instruments and controls, including local panels, shall be suitable for operation in the open where the temperature and relative humidity can go as high as 65°C and 93%, respectively. Temperature, humidity and salt content in the atmosphere are ideal for fungus growth and corrosion. Instrumentation, controls and systems shall be able to operate continuously without their normal physical and functional reliability being affected by the tropical environment. Tropic proofing shall be accomplished by selection of materials not susceptible to fungus growth or moisture. Treatment of any susceptible materials shall be with a protective coating to prevent the growth of fungus, to prevent corrosion and to prevent absorption of moisture. Varnish used for the treatment of instrumentation equipment and components shall conform to military specification (USA) MIL-V-173 or suitable substitute with prior approval of Buyer. 4.7 Component and system preparation for final shipment shall be in accordance with Specification A-011. Seller shall submit, in writing, any special handling and storage requirements. 5.0

LEVEL GAUGING SYSTEMS The ATG shall be a field-proven, microprocessor based system for tank level gauging, suitable for custody transfer and/or inventory control purposes as defined in API MPMS, Chapter 3, Section 1B. All ATGs, both Hydrostatic Tank Gauging (HTGs) and Servooperated Automatic Tank Gauging (STGs), shall be part of the same gauging system. 5.1

Hydrostatic Tank Gauging (HTG) System Figure 1 indicates a typical HTG system and the calculations required of the system. The system shall consist of, as a minimum, the following components and capabilities. a. Two smart electronic pressure transmitters for measurement of hydrostatic head of liquid in the tank. The first transmitter shall be located near the bottom of the tank, above the anticipated sediment level. The second transmitter shall be located above the lower transmitter, preferably in a vertical plane, approximately 2.5 meters or 25 percent of the maximum safe fill height, whichever is less.

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 5 of 19

Mounting and structural support of these transmitters shall conform to Figure 2 and should take into account the manufacturer’s recommendation. b. On pressurized tanks, a third smart electronic pressure transmitter shall be furnished for measurement of static pressure in the tank and shall be installed in the vapor space of the tank. c. One remote interface unit (RIU) for receiving and processing inputs from the above transmitters and the Resistance Temperature Detectors (RTD) temperature element(s) or transmitter(s) (furnished by others). Communication mode between the process sensing/transmitting devices and the RIU shall be manufacturer’s standard. d. 5.2

Level connection shall avoid fill and drain line areas.

Servo-operated Automatic Tank Gauging (STG) System

STG systems shall consist of, as a minimum, the following components and capabilities. The STG shall be furnished by the tank supplier, complete with the internal stillwell and structural supports as indicated in Figure 3. a. One microprocessor controlled tank gauge, suitable for top mounting on a cryogenic product tank. Metallurgy of the STG shall be as specified on the instrument data sheet attached to the procurement documents. b. The Seller shall furnish the necessary components in his STG system to measure (or calculate) the following process parameters and transmit them, via a common field mounted translator, to Owner’s Distributed Control System (DCS) (see paragraph 5.3): • •

Liquid level in millimeters, Spot and average temperature in °C.

c. The data shall be utilized by the DCS for the calculation and/or indication of level, temperature(s) and volume of the product. d. Stilling wells shall be supported directly by the bottom plate of the tank, where it is judged that no movement of the bottom plate will occur, such as in the case of tanks on rigid foundations. Where settlement of the bottom plate is anticipated, stilling wells shall be supported from the tank shell. e. Pressurized storage tanks shall require the servo-driven gage transmitter to be mounted on a full bore ball valve atop a calibration chamber on the tank roof connection flange. The metallic measuring cable (wire) shall be of Invar (an alloy of nickel and iron that exhibits very low thermal expansion). The measuring drum within the servo-driven gage transmitter chamber shall be fully temperature compensated. Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 6 of 19

f. The servomechanism measuring drum shall be magnetically coupled to the servo drive variable speed positioner, so that the drum compartment that is exposed to the tank contents is physically isolated from the instrument compartment. The instrument compartment shall be gastight, so that flammable vapor cannot enter the instrument compartment and escape to the outside atmosphere. g. Servo-driven displacer gage transmitters shall be equipped with four independently adjustable level alarm switches. High and/or High/High alarm contacts integral to the level transmitter shall be used only as a secondary alarm function and shall not perform an interlock or Emergency Shutdown (ESD) function. h.

Each displacer type level gage shall be equipped with a lower reference point. The lower reference point shall be a fixed horizontal plate. The plate may be welded directly to the tank floor plate, or affixed to the tank shell, or attached to the fixed lower end of a required stilling well. If the plate is attached to the stilling well, the plate height shall be not less than 50.8 mm (2 in.) above the tank floor plate. The level at the reference plate shall be tank zero for purposes of calibration.

i.

Each displacer type level gage shall be equipped with an upper reference point, known as the upper tank stop reference point. Ullage measurements and calibration shall be based on this upper reference.

j.

Where a stilling well is required, the size of the well shall be determined on the basis of the manufacturer's recommendation for the particular gage installed. The pipe size of the stilling well shall be dependent on the following: •

Stilling well height in meters.

•

Type of gage installed.

•

Travel of the measuring wire over the measuring drum width in millimeters per meter.

•

Required accuracy of final measurement

The following general rule may be used to size the stilling well D = d + 70 + Ln

Where:

Document1

D

=

diameter of stilling well in millimeters.

d

=

diameter of displacer.

L

=

height measured from top in meters.

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 7 of 19

n = allowable deviation of the stilling well from the vertical in millimeters per meter. 5.3

Communication Communication between ATG and Owner’s DCS shall be serial interface by fiber optic or co-axial cable. MODBUS RTU protocol is preferred; other protocol requires Owner’s written approval. Common field mounted signal translator unit(s) capable of receiving data from both HTGs and STGs and communicating with the DCS shall be provided, if required. 5.4

Control and Display

The Seller shall quote a personal computer (PC), if normally required for his system, as a separate line item in his proposal. It is preferred that the Owner’s DCS be utilized to perform all of the functions of the ATG system which would normally be performed by the Seller’s PC. The Seller shall furnish the Owner a software package of Seller’s system, in mutually agreed upon form, suitable for installation on DCS. The Seller shall work the Owner/DCS vendor in order to furnish a software package that is fully compatible with DCS capabilities (e.g. communication with supervisory computers and printers, password security, hard-wired discrete or serial link control outputs). The Seller shall provide detailed instructions for loading, initializing, configuring, and operating the software on DCS. The software shall include the Seller’s standard system function, display, and report capabilities plus optional capabilities specified on the instrument data sheet. The software package shall be the Seller’s current edition with a minimum of one year’s operating time in service. The Seller shall provide historical performance data on his software prior to receipt of purchase order. The Seller shall provide a receiver type liquid level indicator (meter) suitable for mounting at grade near the base of the relevant tank. Level indication shall be (1) direct reading in SI units or (2) zero to 100 percent uniform with multiplying factor in SI units permanently affixed to the dial face. 5.5

Power Supply

The Contractor shall provide 120-volt AC, 60 Hertz, single-phase Uninterrupted Power Supply (UPS) power for the ATG, which in turn will supply power for operation of the electrical circuits and instruments associated with the ATG.

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

5.6

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 8 of 19

Temperature Measurement

The Seller shall furnish the following temperature sensing/transmitting devices, as required, in accordance with API MPMS 7.4. Platinum 100 ohm resistance temperature (RTD) elements shall be utilized for temperature measurement in ATG systems. a. Single point RTDs shall be provided for use by HTG systems in determining liquid volume at 15°C. Assembly shall be 1m minimum length and located approximately midway between the hydrostatic head transmitters. b. Single point RTDs may be utilized on tanks of 5000 bbl. capacity or less where temperature stratification is not likely to occur. c. A temperature averaging probe, as defined in API MPMS 7.4, utilizing multiple RTD type elements shall be provided for tanks greater than 5000 bbl. capacity where temperature stratification is anticipated and in cryogenic tank service, regardless of size. d. When specified on the instrument data sheet, smart electronic temperature transmitter(s) shall be furnished with the temperature element(s). 5.6

Calibration and Testing 5.6.1

Factory Acceptance Test

The Seller shall perform factory calibration and testing on the HTG(s), including software, prior to shipment. Seller’s PC, with Buyer-approved software package, may be used for the factory tests. Unless waived in writing, the Buyer or his representative shall witness the testing. 5.6.2

Site Acceptance Test

The Seller may be required to perform calibration and testing on the HTG(s) at the plant site, utilizing the Buyer’s DCS. The Seller shall include the cost for this work as a separate line item in his proposal. 5.6.3

Field Calibration

The procedure for the initial operational calibration of the HTG and the periodic calibrations required for accuracy and repeatability are described in detail in API MPMS 3.1B. The procedure to be followed will depend on the purpose of the HTG. Calibration specifications (error limits) and procedures of HTG systems for use in Custody Transfer service are much more stringent than those required for Inventory Control service. Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

6.0

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 9 of 19

ALARMS AND SHUTDOWNS Level Alarm and Shutdown/Interlock systems shall comply with the requirements and specifications in API-2350 and NFPA-30. 6.1

Alarms 6.1.1 Level alarm systems shall be independent of tank level gauging systems. Level alarms shall be powered by and transmitted to DCS for display and logging via routing separate and apart from level gauging systems. In addition to DCS alarm, the system shall provide visual and audible alarms, installed in location(s) occupied by personnel during product receipt. The visual and audible alarms shall be initiated upon the occurrence of any of the following: a.

The existence of a high liquid level in the storage tank. b. An electrical circuit open or a ground fault in the high level alarm initiating circuit or the signaling device circuit. c. The failure of the high level alarm system control equipment (integral internal supervision). 6.1.2 services.

The above criteria shall apply to the following

a. Tanks containing a Class I liquid shall be equipped with a high level alarm to prevent overfill. b. Tanks with heating coils shall be equipped with a low level alarm to prevent drying and overheating of the coils. c. Low pressure refrigerated storage tanks, cryogenic storage tanks, high pressure spheres and cylindrical storage vessels shall be equipped with high level alarms to prevent overfilling. 6.1.3 On tanks containing other than Class I liquid, high and/or level alarms may be an integral part of a level gauging system provided they perform no safety interlock or shutdown function. Visual and audible alarms other than DCS are not required on these services.

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

6.2

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 10 of 19

Shutdowns/Interlocks 6.2.1 In addition to the high level alarm system requirements, each storage tank containing a Class I flammable liquid and located within an unattended facility shall be equipped with a high/high level (HHL) detection, alarm and shutdown system. The HHL system shall be capable of shutting off or diverting the flow of flammable liquid at the point of origin within the facility or at the point of receipt into the storage tank in the event of a high/high liquid level or a power failure in the level-alarm system. 6.2.2 High/high level detection and alarm devices performing interlock and/or shutdown functions required to be installed in Class I flammable liquid service in accordance with API RP 2350 and NFPA 30 shall be considered to be in critical service. These devices shall not be subservient to or an integral part of any other device or system, including the tank gauging system. However, a parallel alarm function may exist within a DCS or other related control and/or information system. 6.2.3 The Triple Modular Redundant (TMR) system in the area Remote Instrument Enclosure (RIE) shall be utilized in these shutdown/interlock services with the following possible exceptions. a. If distance from TMR to shutdown device exceeds TMR capabilities. b. If the liquid involved in an overflow is not Class 1 and/or will not present a safety or operational hazard. Shutdown/interlock systems other than TMR (e.g. hardwired relay logic) may be considered for these exceptions. Implementation requires Company approval. Shutdown and interlock systems, regardless of type, shall be powered by Buyer’s UPS system. Shutdown alarms shall be transmitted via serial link from TMR, or via hardwire from other types, to DCS for display and logging via routing separate and apart from level gauging systems.

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

6.3

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 11 of 19

Level Detectors and Switches 6.3.1

Detectors

Point level detection for high and high-high alarm systems in cone-roof atmospheric tanks shall be implemented with external chamber float type detectors (manufactured by Magnatrol or equal). The detector chamber shall be piped to permit cleaning, testing, and calibration while the tank is in service. Testing and calibration shall not require filling the tank above its normal fill level. Refer to Figure 4 for schematic. Point level detection for high and high-high alarm systems in pressurized and/or refrigerated tanks and spheres shall be implemented with a thermal dispersion (heated thermocouple) type temperature detector (manufactured by Thermocouple Products Co. or equal). The thermocouple(s) shall be the ungrounded type. Refer to Figure 5 or 7 for detail. Where it may be required to install a thermocouple probe in a pressurized tank, three (redundant) flanged probes shall be installed. They will be configured for 2oo3 voting shutdown. Where it may be required to install a thermocouple probe in a refrigerated tank, where internal tank pressures do not exceed 21 kPa, the probe shall be mounted on an appropriately sized standpipe atop a full-bore, approvedtype ball valve so that the probe may be withdrawn through a compression gland and replaced as a unit without removing the tank from service. Such a design shall require specific Company approval. Point level detection for high and high-high alarm systems in floating roof tanks shall be implemented with a slack cable type level detector. Separate detectors are required for high and high-high alarms. Refer to Figure 6 for detail. A variety of other types of detectors are available for consideration when process conditions warrant and may be used with written approval from the Company. (Refer to API 2350, Appendix D). 6.3.2

Switches

Switches shall be hermetically sealed, single pole double throw, micro-switch type in weatherproof enclosures and certified for the electrical area classification in which they are to be installed. Switch contacts shall open to alarm or initiate a shutdown or interlock action.

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

6.4

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 12 of 19

Testing, Inspection and Maintenance

Prior to commissioning, the high level alarm/shutdown system(s) shall be tested for operability and performance in accordance with applicable specifications and code requirements. Procedures for testing, inspection, and maintenance of overfill alarm and protection systems shall be established taking into account API 2350 requirements and manufacturer’s recommendations.

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Document1

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 13 of 19

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 14 of 19

FIGURE 2

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 15 of 19

FIGURE 3

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 16 of 19

FIGURE 4 EXTERNAL CHAMBER TYPE FLOAT SWITCH

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 17 of 19

FIGURE 5 FIGURE 5 HEATED THERMOCOUPLE ASSEMBLY - HIGH-LEVEL PROBE

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 18 of 19

Explosionproof displacement switc h (for two-s tage sys tem, two s eparate s witc h units are required, mounted a minimum of 380 mm apart.) Explosionproof flexible connector Conduit

Operation Checker Cable

Linkage

Displac er

Seal Floating Roof

Cable Guide

High/High Setting

Seal High Setting Floating Roof

Acc ess ible at ground level

NOTE: Two-stage system shall be defined as one that requires a high level alarm as well as a high/high Level alarm. Each alarm shall require a separate and dedicated device Each switch housing including mountings and operation checker shall be grounded to tank shell By approved flexible metallic bonding jumpers.

FIGURE 6 SLACK CABLE TYPE HIGH/HIGH DETECTOR MOUNTED ON INTERNAL FLOATING ROOF TANK

Document1

CONTROL SYSTEMS ENGINEERING

Saudi Yanbu Petrochemical Company Yanpet Expansion Project Yanbu, Saudi Arabia Fluor Daniel Contract 6820XX

Fluor Daniel Intercontinental, Inc. Specification No. 2J-010 Rev 1, 25April97 Page 19 of 19

DETAIL OF PROBE TIP IS SHOWN IN FIGURE 5

FIGURE 7 TC PROBE ASSEMBLY INSTALLED IN DOUBLE ROOF TANK

Document1

CONTROL SYSTEMS ENGINEERING