03430 Non-Invasive Measurement of Corrosion of Flange Sealing Surfaces (51300-03430-SG)

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Non-Invasive Measurement of Corrosion of Flange Sealing Surfaces

John J. Nyholt

BP-America

501 Westlake Park Blvd.

Houston, TX 77079

Frank Dodd

Automated Inspection Systems

4861 Sunrise Drive

Martinez, CA 94553

ABSTRACT

Piping and pressure vessel nozzle flange leaks contribute to the loss of containment,health, safety, and environmental (HSE) issues in the petrochemical industry. This paper discusses a project to mitigate flange leaks through a non-intrusive nondestructive (NDE)technique by early detection and quantification of flange face corrosion.

A case study of two amine units from a US gas plant is presented. Process leaks hadoccurred on piping and nozzle flanges due to CO2 corrosion and erosion of raised-face

sealing surfaces. Several corroded flanges were removed and submitted for a study of advanced NDE detection and sizing techniques capable of in-service inspection prior to ascheduled plant maintenance shutdown. If possible, the NDE techniques were to usestandard NDE test equipment and conventionally trained NDE technicians. During phaseI of the project, a specialized manual ultrasonic shear wave (UT-SW) procedure wasdeveloped and used for the initial on-stream inspection. In phase II, an ultrasonic imagingtechnique was developed using an automated ultrasonic imaging system (AUT) and aspecial miniature scanner that rides on the outside diameter of the flange hub.

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CORROSION2003 Paper No.

03430

1

Copyright

2003 by NACE International. Requests for permission to publish this manuscript in any form, in part or in whole must be in writing to NACE

International, Publications Division, 1440 South Creek Drive, Houston, Texas 77084-4906. The material presented and the views expressed in this paper are

solely those of the author(s) and not necessarily endorsed by the Association. Printed in U.S.A.



After some successful field trials, both phase I and phase II test methods expanded toother petrochemical applications such as inspection of HF-Alky refinery pipe flanges,H2S, and other services where flange damage may occur. Other flange designs, such as

ring type joints (RTJ’s) were also added to the project. After 18 months of use, the UTtechniques were released to interested petrochemical companies within the AmericanPetroleum Institute (API) and the Petroleum Environmental Research Forum (PERF)industry consortium. The techniques were also given to professional NDE trainingcompanies in the US and UK in order to promote its HSE benefits across the industry. Asof this writing, 12 inspection companies have trained ultrasonic technicians on themanual technique.

Key Words: Flange corrosion, non-destructive testing, ultrasonic examination, CO2

corrosion, HF-Alky corrosion

INTRODUCTION

A BP gas plant in Colorado experienced a sharp increase in hazardous liquid leaks in piping and pressure vessel nozzle flange connections in amine service. The company

carries a No-Leaks policy as part of their “no harm to people, property, or theenvironment” program. Subsequently, the business unit tasked the company’s UpstreamTechnology Group (UTG) to investigate and mitigate the cause of these leaks. The project included the development of a non-intrusive NDE method capable of detectingand sizing raised face flange corrosion of amine piping flanges. Seven corroded flangesamples were sent to the UTG-NDE department for the feasibility study. This paper discusses the NDE technique(s) developed and implemented over the last 2 years. For the

purposes of this project, flange sizes and pressure ratings range from 1 inch to 20 inchesin diameter and 150 PSI to 600 PSI pressure ratings. Other flange sizes and pressureratings are inspectable using the implementation guidelines of the special NDE procedures from this project.

The project focused on examining the integrity of the flange-sealing surface (raised faceof the flange) as the primary leak path. The field samples indicated severe corrosion of the raised face, flange bore, and flange to pipe weld. Conventional radiography (RT) or ultrasonic shear wave (UT-SW) examination is capable of inspecting the flange to pipe butt weld, and the substantial thickness of the bore made corrosion measurement less of aconcern. The project was later expanded to include ring type joints, and other types of

damage mechanisms such those found in refinery HF-Alky units.

The target performance parameters for the non-intrusive NDE technique were:

1.Detection and measurement of the radial extent of flange face corrosion fromthe inside diameter bore to raised face corner to the outside diameter of the raisedface.


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2. The radial extent of corrosion noted against the known location of the sealingring of the flange. For raised face flanges, a flexitallic CG type gasket is typicallyused.3. The depth of corrosion into the flange face is usually considered immaterial for leak path considerations.

4.A measurement accuracy of 0.050-inches (12.7mm) of radial corrosion loss wasconsidered acceptable.

EXPERIMENTAL PROCEDURE

Due to the complexity of flange geometry and inaccessibility of the raised face area,radiography was excluded as a viable non-intrusive flange face inspection method.Another fully volumetric inspection technique was needed. Ultrasonic examination wasselected as the most reliable method for detecting and sizing flange corrosion.

Two ultrasonic techniques were selected for this application: one transmitting sound from

the flange neck (figure #1), and one from the back of the flange (see figure #2).

Figure 1 - Insonofying from the flange neck

Figure 2 - Insonofying from the back of the flange

Test trials performed on the corroded samples revealed the advantages and limitation of each technique:


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Insonofying from taper of the nozzle neck: • Feasible but time consuming in the field application

• 360-degree coverage possible

• Poor sensitivity (tends to find only to gross corrosion)

• Complicated, requires a high level of operator expertise• Difficult to model. Flange taper angles and lengths are

not specified in ANSI B-16.5

• Limited scan access due to the short length of the taper

• Contoured probe shoe requirement for most flange sizes

• Requires sound skip off of bore ID for certain flange sizes

Insonofying from the back of the flange (between the bolts): • Only limited coverage beneath bolt areas (Must use beam skew angle)

• Currently the most sensitive test available

• Utilizes the surface characterizing capabilities of a 45 degreeshear wave incident angle (Can detect raised face serration lines)

• Less complicated to apply than the nozzle neck technique

• Can be modeled from flange design specifications in ANSIB-16.5

• Can be automated or semi-automated with specializedhardware and software

Without an inordinate amount of operator expertise, applying ultrasound from the flange

taper would fail to reliably detect flange face corrosion. The varying sound path and beam spread characteristics of this technique yielded poor sensitivity and resolution.

Transmitting ultrasound from the back of the flange yielded good flange face flawdetection sensitivity and resolution. The method proved useful to simultaneouslydifferentiate between corroded and non-corroded areas of the flange face and adjacent bore by coordinating ultrasonic reflections and probe positions related to the bore toraised face corner, the edge of the corrosion line (see figure #3).


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Figure 3 - Corner trap signals vs. probe position

NDE Procedure Development

The manual UT technique is dependent on accurate sound mapping in relation to the position of the 45-degree UT-SW probe as measured from the outer edge of the flangehub (common reference point). For each welding neck flange size and pressure rating, a1:1 ratio drawing is created from tables 9, 12, 15 and 19 of ASME B-16.5. The length of the raised face is calculated and added to the drawings. When appropriate, ultrasonicthickness measurement and caliper readings are taken in order to create accurate fielddrawings. The sound path and probe positions for the bore to raised face corner and outer diameter of the raised face are added to each drawing to define the ultrasonic scan boundaries for that particular flange. The UT examiner carries a book of flange drawings

as well as an ultrasonic flaw detector, protractor, steel measuring ruler, UT probes andcouplant. The relatively portable and lightweight equipment allows for a one-man crewand easy access to difficult flange locations.

Figure 4 – ASME/ANSI B-16.5 dimensioning

For the full range of flange sizes and locations, some flanges require additional ultrasonicsound beam angles in order to provide full coverage of the raised face. Quick-connect


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wedges in 45, 50, 55, and 60-degree shear wave angles are called out for certain flangesin the flange inspection procedure.

A miniature probe (0.25 inch (6.35m) diameter or less) is typically used for most flangesizes. The UT system is calibrated to sound path distance with a carbon steel miniature

distance calibration (DSC) block. No ultrasonic sensitivity calibration is performed inthis application. The test is designed to work with no surface preparation under mostconditions. Paint thickness, condition, and surface irregularities prevent uniformultrasonic coupling, and flanges were found to vary in ultrasonic attenuation levels. Theoperator is expected to adjust instrument gain up or down to maintain a 5-10% amplitude“rolling surface” signal from the raised face serrations on the instruments A-scan display.

The probe is raster scanned between the bolts 360 degrees around the flange. UT signalsand probe positions are measured from the OD of the flange hub to indicate the raisedface to bore corner signal and the outside diameter of the raised face diameter refractedsignal. Intermediate signals indicate corrosion, and their probe positions are recorded as

flange face corrosion.

INITIAL FIELD APPLICATION

A single ultrasonic level III operator performed the first field application of the manualUT technique on two amine units in Colorado. Plant operations, maintenance, andinspection personnel, with the help of UTG corrosion engineering and NDE specialists,defined the scope of this work using operating conditions, process history, and qualitativerisk analysis. Unit piping drawings (P&ID’s) were used to highlight potential flangedamage areas with respect to the amount of CO2 treated, pressure drops, flow velocities,and temperature. 194 flanges were chosen for on-line inspection. Scaffolding was

supplied where appropriate, and orange ribbons were used to flag test locations. Allinspections were completed in two man-weeks.

To the author’s knowledge, there is no industry standard for acceptance criteria, risked based inspection (RBI) ranking scheme, or fitness for service (FFS) analysis schemeexists for flange corrosion. However individual inspection and maintenance departmentsmay have rules of thumb for replacing damaged flanges. For this project, the followingacceptance criteria was used:

• Accept: No flange face corrosion noted

• Monitor: Flange face corrosion noted. Gasket sealing surface in tact.

• Reject: Flange face corrosion has compromised the gasket sealing surface

Rejected flanges were recommended for repair or replacement. “Monitor” flanges were placed on an 18-month re-inspection interval. Note that some petrochemical companieshave adopted a 50% loss of sealing surface area as a flange replacement criterion.

The timing of this inspection was set at 7-months prior to a scheduled plant shutdown.


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Inspection Results

CO2 corrosion was prevalent in the amine trains. Of the first twelve flanges examined,eleven had severe bore and flange face corrosion (> 50% loss of the flange face). Inaddition to the intermediate ultrasonic corner trap signals from corrosion, ultrasonic

signals would dance from mixed phase flow of product swirling in the corrosion/erosioncavities of the flange face. The plant isolated and removed one 8 inch 150 lb pipe flangewith 0.50 inch (12.7mm) of corroded flange face reported per the new UT technique.Flange face corrosion was verified, and the actual extent of this corrosion was measuredat 0.483 inch (12.27mm).

The test results for all of the 194 flanges inspected are listed in Table #1: The drawingnumber inspection point and amine train relate to the location of each inspection point.The flange size, flange rating and flexitallic CG gasket ID relate to dimensionalrelationships of the flange and gasket-sealing surface. The bore to gasket ID representsthe open crevice between the ID of the raised face to the inner edge of the gasket seal.

One of the useful corrosion measures is the percent of this gap that is corroded. A valuegreater than 100% indicates that the corrosion has exceeded the gasket seal, which isreported in the column for estimated flange face loss behind the gasket. The radialmeasurement of flange face corrosion from the ID bore is also noted. Bore corrosion isnoted, but not measured. An “accept” flange that has bore corrosion noted indicates thatthe flange is not a present concern even though the damage mechanism is present. Thefirst flange of each pair noted represents the one closest to the vessel (nozzle), the oneclosest to a block valve, or the upper flange in a vertical pair. The second nozzlementioned always denotes the opposing flange.

The initial inspection resulted in 36 replace recommendations, 56 flanges were noted for

monitoring, and 23 were not examined because the were either inaccessible, or had beenupgraded to stainless steel sometime prior to the test. For those that were to bemonitored, additional field notes recorded the flange face corrosion/erosion as either general (equally corroded around the flange face), or localized (limited to one side or portion of the flange face). If the manual UT operator is properly qualified, the test iscapable of characterizing corrosion and is repeatable within 0.100-inch (2.54mm). Areview of the unit P&ID’s and examination spreadsheet can identify particular areas of the unit where damage is prevalent. In this application, this would include flanges relatedto the amine regenerator reboiler, the rich/lean amine exchangers, and the rich amineflash tank.

The 7 month lead time on flange damage allowed the plant to prefabricate piping spoolswith replacement flanges, procure replacement pressure vessel nozzles, plan manpower

for repairs, and determine a realistic shutdown time. At the plant’s discretion, many of the flanges marked for monitoring were instead replaced. In total, 70 flanges wereremoved from the two amine trains. Each flange was visually inspected, and the radialextent of flange face corrosion measured with calipers. Given the 70-flange test population, the following manual UT performance measures were as follows:


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• 58 correct calls (within 0.100 inch (2.54mm) of corrosion)

• 10 false calls (corrosion not detected within 0.100 inch)

• 2 false-positive calls

An 83% correct call rate for 0.100-inch measurement accuracy was considered

acceptable an initial field demonstration.A 15% false call rate (successful detection, but less than 0.100-inch measurementaccuracy) was attributed to operator interpretation error and mechanical measurementerror (use of a steel ruler to measure probe positions in difficult body postures).A 2% false-positive call rate (called corrosion when none was present) was acceptable,and was also attributed to operator data interpretation error.

Based on the initial field trial, the test was very successful in terms of detectingcorrosion, successful in measuring corrosion, and has a low probability of false positivecalls. The primary error sources are the experience level of the operator, proper datainterpretation, and correct mechanical measurement of probe positions in relation to the

A-scan data.

The new manual UT technique was written into a specific UT procedure and transferredto other business units in the UK and US. A 3-day special application course was givenin Aberdeen, Scotland and Houston, Texas. The 70 flange samples were used for operator training, hands-on experience, and operator qualification exams. After the manual UTtechnique was perfected, the project moved on to Phase II; semi-automated ultrasonicimaging.

SEMI-AUTOMATED UT INSPECTION TECHNIQUE

A US automated UT manufacturer was selected to design and build a miniature flange

scanner with magnetic wheels that would ride on the outside diameter of the flange hub(X-Axis) and a transducer arm that would advance and retract the UT-SW probe on the back of the flange (see photo in Figure #5).

Figure #5 – Semi-automated flange scanner


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The scanner would interface with a laptop PC system with an ultrasonic pulser-receiver board and digitizer card. UT-imaging software would record raw A-scan data for every0.01-inch (.254mm) of probe motion for playback and coordination with Y-axis probemotion within 0.001-inch (.025mm) accuracy. As the most complicated aspect of themanual UT test is coordinating the probe position with the ultrasonic response of the

instrument, the semi-automated test automatically records the two together as a permanent record, and outputs the resulting ultrasonic image into a cross sectional viewwith overlay of the actual flange face dimensions (See figures #6A and 6B).

Figure #6A - Ultrasonic image of a raised faced flange with no corrosion

The description and use of the ultrasonic imaging screens are as follows:

• The upper left hand image is a C-scan, or plan view.

• The upper right hand image is a raw data cross sectional imageuncorrected for sound beam angle.

• The lower left hand image is the B-scan cross sectional image thatcontains gated (selected sound path) ultrasonic data.

• The lower right hand image is the A-scan raw data. The data can bescrolled to exactly repeat the A-scans for each probe position of each scan

line, as useful training tool for UT operators.

All screens update with each other with curser movement in any one of them. Thecorrosion at any given point may be measured directly by curser placement and numericreadout.


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Figure #6B – Ultrasonic image of raised face flange with corrosion

In figure #6B, the C-scan image indicates corrosion for each scan line 360 degrees around theflange. The image deflection toward the right indicates the radial extent of corrosion around theflange. The remaining screens display images from each particular scan line chosen from the C-scan image:

The procedure for the semi-automated technique is simple. Pre-written system parameter files are stored for immediate use. The UT operator simply enters flange size and

pressure rating into the laptop computer, places the scanner at the 12 O’clock position of the flange, moves the transducer to the OD edge of the flange, and starts the scan. Theflexible scanner arm allows the operator to lift the probe over the flange bolts andcontinue scanning between the bolts. The average inspection time per flange is 15minutes including set-up, data collection, and tear down. The suitcase size UT systemand scanner connect with one umbilical chord.

ONGOING INSPECTION PROGRAMS

The awareness and use of proactive inspection of flange corrosion is still emerging across

the industry. These non-intrusive NDE inspection techniques can assist the corrosionengineer with confirming the integrity of pipe flanges and pressure vessel nozzles at risk for corrosion, and measure the extent of damage for monitoring, repair (weld-out andmachined in-place), or replace decisions. Following the release of the manual and semi-automated flange inspection techniques, several petrochemical companies have askedtheir NDE contractors to learn both techniques. However at the time of this writing, themanual technique has been the most common. The semi-automated test is less popular due to the $35,000 investment in equipment. It is assumed that the manual test may suffer


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from the same operator error as conventional manual UT, and that the semi-automatedtest takes out nearly all operator error. As this is an on-line test, much of the datavalidation for the work performed to date is pending some future shutdown.

The semi-automated UT test is particularly popular with refining HF-Alky units, where

flange leaks due to corrosion are understood as a high HSE risk. A refinery in CorpusChristi used the semi-automated technique on a HF-Alky unit, and validated some of thefield data. Feedback on the difference between the semi-automated UT results and theactual measured corrosion:

• Average difference: 0.04-inch (1.020mm)

• Maximum difference: 0.08-inch (.203mm)

• Minimum difference: 0.01-inch (.254mm)

Ring Type Joints

These techniques have also been used to inspect the faces of RTJ joints, however for some RTJ flange sizes, the ring groove may shadow the area of interest. In some cases, itis best to insonify from the nozzle neck. According to reports from the field, acombination of techniques works best. However work on improved ultrasonic techniques,such as ultrasonic phased array, is in progress.

Training Programs

To date, three training courses have been held in the US and five in the UK. There are 15approved manual UT operators in the US and 20 in the UK. The training program,including equipment and flange samples have been handed over to a professional NDE

trainer. More three-day courses are planned for 2003.

User Feedback

End-users and students from previous flange inspection courses routinely provide both positive and negative feedback on the techniques. Comments that resulted in techniquemodifications include:

1. The default criteria of reject for any loss of gasket seal can result in a false call due to acorrosion line that follows the ID of an off-center gasket.Solution: Add a measurement of the gasket OD to the OD of the flange hub to measure

and compensate for off-center gaskets.

2.While inspecting HF-Alky unit flanges, bulky PPE (gloves) prevent the use of finemotor skills required for these techniques.Solution: A second-generation semi-automated scanner and manual UT probe holder with digital probe position readout were designed for use with heavy gloves.


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3. Neither technique works well with one peculiar type of HF-Alky corrosion thatexhibits flange face corrosion with an unusually smooth surface (typically from anerosion component). Both of the current techniques rely on corner trap signals from theedges of the flange face corrosion. The manual technique performed poorly in detectingthis type of damage, however the semi-automated technique is capable if indicating that

the bore to raised face corner trap is out of place (corroded) and alerts that operator thatthis condition is present.Solution: Ultrasonic phased array technology (UT-PA) could generate where a greatnumber of sound beam angles (by insonofying from the nozzle neck or the back of theflange hub) to interrogate the flange face in an instant by drawing a high-resolutionimage of the face and corrosion (See figure #7). The feasibility of this technique iscurrently under investigation. UT-PA equipment is currently cost prohibitive for most NDE providers, however the cost and physical size of the equipment are both reducingrapidly. A hand-held UT-PA with a miniature linear array probe is now commerciallyavailable for around $50,000 US.

Figure #7 – Ultrasonic phased array application

CONCLUSIONS

A successful on-line inspection technique for piping flanges and pressure vessel nozzleshas been demonstrated. In the case study noted, two weeks of unit shutdown time for twoamine units were credited to this new UT inspection technique.

Apart from known flange face corrosion problems at gas plants with CO2 and H2Sdamage mechanisms, and refinery HF-Alky units, the need for such an on-line inspectiontechnique is in the discovery stage. Industry codes around RBI and FFS as well asindividual plant inspection programs should consider flange corrosion when calculatingthe effects of potential damage mechanisms active on their process units.

When flange face damage is detected, semi-automated UT may be used to image thedamage as a permanent record, and monitor its growth in subsequent examinations.

As new emerging technologies, such as UT-PA mature, they may complement or evenreplace the techniques discussed in this writing. A single probe may be placed on thenozzle and image the flange face without raster scanning or the use of a magneticwheeled scanner. Time will tell.

ACKNOWLEDGEMENTS


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AIS Inspection SystemsSunrise, CA

Davis NDEAlabaster, AL

Mechanical IntegrityHumble, TX


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Table #1 – Initial inspection examination results

Drawing

#

Inspection

Point

Amine

Train

Flange

Size(inch)

Flange

Rating(psi)

FlexitallicCG Gskt

ID (inch)

Bore

to

GsktGap

(inch)

BoreCorrosion

noted Y-N

Flange Face

Corrosion(inch)

Percentof Gap

Corroded

Estimated

F.F. loss

behindGskt.

(inch)

ReplaceMonitor

AcceptMFD-201 1 Nozzle 1 8 300 9.188 0.59 Y -0.85 144.07% -0.25 Replace

MFD-201 1 Pipe 1 8 300 9.188 0.59 Y -0.6 101.69% -0.01 Replace

MFD-201 2 Nozzle 1 1 150 1.250 0.125 N/A N/A #VALUE! N/A N/A

MFD-201 2 Pipe 1 1 150 1.250 0.125 N/A N/A #VALUE! N/A N/A

MFD-202 1 Nozzle 1 3 600 4.000 0.5 Y 0 0.00% 0 Accept

MFD-202 1 Pipe 1 3 600 4.000 0.5 No 0 0.00% 0 Accept

MFD-202 10 PIPE 1 4 300 5.000 0.5 MINOR 0 0.00% 0 Accept




MFD-202 2 Pipe 1 2 150 2.750 0.375 Y 0 0.00% 0 Accept

MFD-202 2 Valve 1 2 150 2.750 0.375 N/A N/A #VALUE! N/A N/A

MFD-202 3 Pipe 1 2 150 2.750 0.375 Y 0 0.00% 0 Accept

MFD-202 3 Valve 1 2 150 2.750 0.375 Y 0 0.00% 0 Accept

MFD-202 4 Nozzle 1 4 150 5.000 0.5 Y -0.3 60.00% 0 Monitor

MFD-202 4 Pipe 1 4 150 5.000 0.5 Y -0.3 60.00% 0 Monitor



MFD-202 6 PIPE 1 4 300 5.000 0.5 Y -0.45 90.00% 0 Monitor




MFD-203 1 Nozzle 1 and 2 3 150 4.000 0.5 N/A N/A #VALUE! N/A N/A

MFD-203 1 NOZZLE 1&2 3 N/A N/A #VALUE! N/A N/A

MFD-203 1 pipe 1 and 2 3 150 4.000 0.5 N/A N/A #VALUE! N/A N/AMFD-203 2 PIPE 1 10 300 11.313 0.656 N/A N/A #VALUE! N/A N/A


MFD-203 3 PIPE 1 4 300 5.000 0.5 N/A N/A #VALUE! N/A N/A


MFD-203 4 FLANGE 1 8 300 9.188 0.59 Y -0.2 33.90% 0 Monitor

MFD-203 5 pipe 1 8 300 9.188 0.59 y -0.35 59.32% 0 Monitor

MFD-203 6 PIPE 1 3 300 4.000 0.5 Y NOISE #VALUE! Replace

MFD-203 7 PIPE 1 3 300 4.000 0.5 Y NOISE #VALUE! Replace



MFD-204 10 NOZZLE 1 12 150 13.375 0.688 Y -0.2 29.07% 0 Monitor

MFD-204 11 NOZZLE 1 20 150 20.688 0.344 Y -0.4 116.28% -0.056 Replace

MFD-204 12 Pipe 1 10 150 11.313 0.656 N/A N/A #VALUE! N/A Accept

MFD-204 12 Valve 1 10 150 11.313 0.656 N/A N/A #VALUE! N/A Accept


MFD-204 13 Reducer 1 4 150 5.000 0.5 No 0 0.00% 0 Accept

MFD-204 14 Pipe 1 6 150 7.188 0.594 Missed Missed #VALUE! Missed Missed

MFD-204 14 Valve 1 6 150 7.188 0.594 Missed Missed #VALUE! Missed Missed





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Drawing

#

Inspection

Point

Amine

Train

Flange

Size(inch)

Flange

Rating(psi)

Flexitallic

CG Gskt

ID (inch)

Boreto

Gskt

Gap

(inch)

Bore

Corrosion

noted Y-N

Flange Face

Corrosion(inch)

Percent

of Gap

Corroded

EstimatedF.F. loss

behind

Gskt.

(inch)

Replace

Monitor

Accept


MFD-204 2 pipe 1 8 300 9.188 0.59 Y -0.2 33.90% 0 Monitor MFD-204 3 Nozzle 1 8 300 9.188 0.59 Y -0.3 50.85% 0 Monitor




MFD-204 5 Nozzle 1 12 150 13.375 0.688 Noise 0 0.00% 0 Accept





MFD-204 7 pipe 1 12 150 13.375 0.688 Y -0.55 79.94% 0 Monitor




MFD-204 9 Pipe 1 12 150 13.375 0.688 N/A N/A #VALUE! N/A N/A



MFD-205 10 PIPE 1 1.5 150 2.125 0.313 NO 0 0.00% 0 Accept


MFD-205 12 PIPE 1 10 150 11.313 0.656 NO 0 0.00% 0 Accept

MFD-205 13 Pipe 1 10 150 11.313 0.656 NO 0 0.00% 0 Accept

MFD-205 2 Nozzle 1 3 150 4.000 0.5 Y Minor #VALUE! 0 Monitor

MFD-205 2 Pipe 1 3 150 4.000 0.5 Y Noise #VALUE! 0 Accept


MFD-205 3 Valve 1 8 150 9.188 0.59 Y -0.35 59.32% 0 Monitor










MFD-206 1 Reducer 2 1.5 300 2.125 0.313 NO 0 0.00% 0 Accept

MFD-206 1 Valve 2 1.5 300 2.125 0.313 NO 0 0.00% 0 Accept

MFD-206 2 Pipe 2 1.5 300 2.125 0.313 NO 0 0.00% 0 Accept


MFD-206 3 Pipe 2 1.5 300 2.125 0.313 NO 0 0.00% 0 AcceptMFD-206 3 Valve 2 1.5 300 2.125 0.313 NO 0 0.00% 0 Accept

MFD-206 4 Reducer 2 1.5 300 2.125 0.313 NO 0 0.00% 0 Accept


MFD-206 5 Pipe 2 1.5 300 2.125 0.313 NO 0 0.00% 0 Accept



MFD-207 2 Valve 2 8 300 9.188 0.59 NO 0 0.00% 0 Accept



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Drawing

#

Inspection

Point

Amine

Train

Flange

Size(inch)

Flange

Rating(psi)

Flexitallic

CG Gskt

ID (inch)

Boreto

Gskt

Gap

(inch)

Bore

Corrosion

noted Y-N

Flange Face

Corrosion(inch)

Percent

of Gap

Corroded

EstimatedF.F. loss

behind

Gskt.

(inch)

Replace

Monitor

Accept


MFD-207 4 Pipe 2 8 300 9.188 0.59 Y 0 0.00% 0 AcceptMFD-207 4 Valve 2 8 300 9.188 0.59 No 0 0.00% 0 Accept


MFD-207 5 Valve 2 8 300 9.188 0.59 No 0 0.00% 0 Accept

MFD-207 6 PIPE 2 8 300 9.188 0.59 Y -0.6 101.69% -0.01 Replace

MFD-207 7 Nozzle 2 8 600 8.875 0.438 NO 0 0.00% 0 Accept

MFD-208 1 Nozzle 2 8 150 9.188 0.59 Y -0.7 118.64% -0.11 Replace

MFD-208 1 Pipe 2 8 150 9.188 0.59 Y Minor #VALUE! 0 Accept






MFD-208 12 Valve 2 8 150 9.188 0.59 N/A N/A #VALUE! N/A Accept




MFD-208 14 Pipe 2 8 150 9.188 0.59 Y -0.5 84.75% 0 Removed




MFD-208 16 Pipe 2 8 150 9.188 0.59 Y -0.5 84.75% 0 Removed


MFD-208 18 PIPE 2 1.5 150 2.125 0.313 Y -0.7 223.64% -0.387 Replace


MFD-208 2 Nozzle 2 3 300 4.000 0.5 No 0 0.00% 0 Accept



MFD-208 3 Pipe 2 6 600 6.875 0.438 Y -1 228.31% -0.563 Replace










MFD-208 8 Valve 2 2 300 2.750 0.375 No 0 0.00% 0 AcceptMFD-208 9 Pipe 2 2 300 2.750 0.375 Y -0.4 106.67% -0.025 Replace





MFD-209 2 pipe 2 4 150 5.000 0.5 Y -0.6 120.00% -0.1 Replace

MFD-209 2 Valve 2 4 150 5.000 0.5 Y -0.6 120.00% -0.1 Replace



16



Drawing

#

Inspection

Point

Amine

Train

Flange

Size(inch)

Flange

Rating(psi)

Flexitallic

CG Gskt

ID (inch)

Boreto

Gskt

Gap

(inch)

Bore

Corrosion

noted Y-N

Percent

of Gap

Corroded

EstimatedF.F. loss

behind

Gskt.

(inch)

Replace

Monitor

Accept


MFD-209 3 PIPE 2 4 150 5.000 0.5 Y -0.95 190.00% -0.45 ReplaceMFD-209 4 Nozzle 2 8 300 9.188 0.59 N/A N/A #VALUE! N/A N/A



MFD-209 6 PIPE 2 8 300 9.188 0.59 Y #VALUE! MINUS BORE




MFD-210 1 pipe 1 6 300 7.188 0.594 NO 0 0.00% 0 Accept








MFD-210 3 Pipe 2 4 150 5.000 0.5 Y -0.5 100.00% 0 Replace


MFD-210 4 Nozzle 2 4 300 5.000 0.5 Y -0.8 160.00% -0.3 Replace

MFD-210 4 Reducer 2 4 300 5.000 0.5 Y -1.09 218.00% -0.59 Replace




MFD-210 7 PIPE 2 4 150 4.000 0.5 Y MINOR #VALUE! 0 Accept






MFD-211 4 NOZZLE 2 10 150 11.313 0.656 N/A N/A #VALUE! N/A N/A

MFD-211 5 NOZZLE 2 2 150 2.750 0.375 N/A N/A #VALUE! N/A N/A

MFD-211 6 NOZZLE 2 8 150 9.188 0.59 Y -0.6 101.69% -0.01 Replace


MFD-213 1 pipe 2 3 150 4.000 0.5 No 0 0.00% 0 Accept



MFD-213 3 Nozzle 2 3 150 4.000 0.5 Y Noise #VALUE! 0 Monitor


MFD-213 4 Nozzle 2 3 150 4.000 0.5 No 0 0.00% 0 AcceptMFD-213 4 Pipe 2 3 150 4.000 0.5 Y 0 0.00% 0 Accept



MFD-213 6 Pipe 1 and 2 8 300 9.188 0.59 Y -0.6 101.69% -0.01 Replace

MFD-213 6 Valve 1 and 2 8 300 9.188 0.59 Y -0.6 101.69% -0.01 Replace

MFD-213 7 Nozzle 1 and 2 8 300 9.188 0.59 Y -0.6 101.69% -0.01 Replace

MFD-213 7 pipe 1 and 2 8 300 9.188 0.59 Y -0.6 101.69% -0.01 Replace

MFD-213 8 Nozzle 1 and 2 8 300 9.188 0.59 Y -0.6 101.69% -0.01 Replace

Flange Face

Corrosion(inch)


17



Drawing

#

Inspection

Point

Amine

Train

Flange

Size(inch)

Flange

Rating(psi)

Flexitallic

CG Gskt

ID (inch)

Boreto

Gskt

Gap

(inch)

Bore

Corrosion

noted Y-N

Flange Face

Corrosion(inch)

Percent

of Gap

Corroded

EstimatedF.F. loss

behind

Gskt.

(inch)

Replace

Monitor

Accept

MFD-213 8 Pipe 1 and 2 8 300 9.188 0.59 Y 0 0.00% 0 Accept

MFD-213 9 PIPE 2 8 150 9.188 0.59 N/A N/A #VALUE! N/A N/AMFD-214 1 PIPE 2 2 150 2.750 0.375 Y -0.28 74.67% 0 Monitor


18

Documents

03430 Non-Invasive Measurement of Corrosion of Flange Sealing Surfaces (51300-03430-SG)