AWS Procedure - Rev 2.pdf

8/10/2019 AWS Procedure - Rev 2.pdf

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Forward

While it is recognized that phased array technology is becoming more widespread and

popular within various industries, it has not yet been specifically addressed by the

AWS. The following document was written to satisfy customer requests. Its purpose is

to serve as a guideline to align the Phasor XS with the current methodology prescribed

in Clause 6, Part F, of the AWS D1.1, 2008 Code.

This is achievable due to the well-established fact that an array transducer with the

same physical properties of size, shape, and frequency, as a conventional monolithic

transducer, will have identical acoustic properties.

This document has been produced in typical procedure format, for the sake of

familiarity. As such, it is intended as a guideline only.


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Table of contents

SECTION PAGE

1. Scope 3

2. References 3

3. Personnel 4

4. Equipment 4

5. Calibration 6

6. Examination 13

7. Indication evaluation and reporting 18

Annex A: dB Accuracy Procedure 23

Annex B: Horizontal Linearity Procedure 29

Annex C: Search Unit Check 33

Annex D: Drawings 37


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1. Scope

1.1.This procedure describes the use of the Phasor XS utilizing the sectorial and

A-scan views. For the detection and interpretation of discontinuities in groovetype welds and the associated heat affected zones (HAZ). Applicable part

thickness range is from 5/16 to 8 inclusive of material thickness as prescribed

byPart F of the AWS D1.12008 code. (herein referenced as the code)

1.2.Limitations

1.2.1. This procedure is not intended for the inspection of tube-to-tube (tubular)

T, Y, K connections

1.2.2. This procedure is not intended for the inspection of base material.

However, discontinuities discovered in the adjacent base material shall be

reported to the Owner / Engineer for disposition.

1.2.3. As a supplement to the method(s) described herein, RT is recommended

for the detection of piping porosity in ESW, and EGW weldament.

1.2.4. For discrepancies between this procedure, and the code, the code shall

hold precedence.

2. References

2.1.American Welding SocietyAWS D1.1 Structural Welding Code Steel

2.2.American Society for Nondestructive Testing (ASNT) - SNT-TC-1A Personnel

Qualifications

2.3.GE Inspection Technologies (GEIT) - Phasor Owner Manual.

(www.geinspectiontechnologies.com)
http://www.geinspectiontechnologies.com/http://www.geinspectiontechnologies.com/http://www.geinspectiontechnologies.com/http://www.geinspectiontechnologies.com/


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3. Personnel

3.1. Personnel shall be certified in accordance with the ASNT SNT-TC-1A, or be

certified in accordance with the employers written practice. Provided that the

employers written practice contains, as a minimum, the requirements of SNT-

TC-1A.

3.2.Personnel performing exams shall be a certified level I, II, or a level III who has

taken, and passed a Level II Practical certification test.

3.2.1. Level I personnel shall only perform exams under the direct supervision

of a level II, or III, and shall not independently (1) conduct exams, (2)

interpret exam results, or (3) write a report of exam results.

3.3.All personnel conducting exams in accordance with this procedure shall

demonstrate proficiency by successfully passing a general, specific and

practical exam administered by a level III, or a Level II so designated by a level

III, and applying the methodology of this procedure and the rules of AWS D1.1.

4. Equipment

4.1.The ultrasonic instrument shall be the Phasor XS.

4.1.1. For compliance with Sec. 6.22 of the AWS code, reference the Phasor

Owners Manual for the technical specifications.

4.2.The search unit shall be comprised of transducer model # 115-000-866,

coupled to wedge # 118-350-037 for straight beam, or the standard 60 AWS

wedge for angle beam. The use of other search units by engineer approval is

not addressed within this document.


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4.3.The International Institute of Welding (IIW) Type 1 or Type 2 ultrasonic

reference block(s) shall be used for distance and sensitivity calibration, a

drawing of which can be found in Annex D, Drawing 2. Other approved

reference blocks (DSC, DS, and SC) may also be used, provided that the

reference sensitivity of the instrument/search unit combination is adjusted to

achieve equivalent results as that of the IIW block. Drawings for these blocks

can be found in Annex D, Drawing 4.

4.4.Any suitable couplant material of glycerin type, or a cellulose gum and water

mixture shall be used between the search unit and base material. A wetting

agent may be added to improve consistency. Light machine oil or equivalent

may be used for coupling on calibration blocks.


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5. Calibration

5.1. General

5.1.1. Reference Annex A and B for equipment qualification requirements.

5.1.2. A transducer element, cable, and coupling check shall be made prior to

an exam or series of exams, and again at the completion of an exam or

series of exams, but not to exceed intervals of 8 hours, and at any time of

suspected system irregularity. Reference Annex C for equipment

programming, and guidance.

5.1.3. The primary testing angle used for calibration shall be selected from

table 5.1

5.1.4. Calibration shall be performed with the Phasor set up in accordance with

table(s) 5.2, or 5.3.

5.1.5. Calibration intervals for sensitivity and horizontal sweep shall be made

by the operator at the location of each weld being tested, and at intervals

not to exceed 30 minutes as testing proceeds.

5.1.6. Recalibration shall be made after:

a) Change of personnel.

b) Time intervals not to exceed a maximum of 2 hours.

c) Any change to the search unit, or changing of the search unit.

d) Any disruption of the electronic circuitry. (i.e. battery swap, powerfailure)

e) Any instance of system irregularity.

5.1.7. The use of corner reflectors shall be prohibited for calibration.


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5.2. Straight beam calibration

5.2.1. With the Phasor programmed in accordance with Table 5.2, place the

search unit on face A and adjust the leg function such that 2 plate

thicknesses are displayed on the screen.

5.2.2. For sensitivity, place the search unit at a location on the base material

that is free of discontinuities. Adjust the gain control to display the first back

reflection at 50% to 75% of amplitude. (A%A reading in the results

window).

5.3. Angle beam calibration

5.3.1. A linear screen range shall be achieved to represent the actual sound

path in metal. The following method describes the use of the IIW2

reference block. However any suitable block described in 4.3 may be used.

5.3.2. Using the primary testing angle, and with the Phasor programmed in

accordance with Table 5.3, adjust the instrument to achieve a linear screen

range as follows:

5.3.2.1. Place the search unit at position D as depicted in Annex D

Drawing 1.

5.3.2.2. Adjust the leg function to display the 2 and 4 radius on the

screen, maximizing the signal(s) amplitude. (NOTE: For this

process, the Material Thickness function may also be adjusted.

However, prior to examinations, the Material Thickness function

shall be returned to the actual component thickness as prescribedin Table 5.3.)

5.3.2.3. Place the beam cursor on the primary testing angle to ensure the

readings in the Results windows are for this angle.


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5.3.2.4. In the CAL submenu (HOME > PART > CAL) adjust the gates to

surround where the beam cursor intersects the reflection from the

4 radius. (NOTE: the gates may also need to be narrowed.)

Maximize the signal response from the 4 radii by adjusting the

probe position. Adjust the gain such that the amplitude response

reads less than 100% in the A%A results window. Adjust the

VELOCITY S until the SA reading in the results window reads 4.

5.3.2.5. In the same manner as described in 5.3.2.4, adjust the PROBE

DELAY such that the SA result reads 2 for the response from the

2 radii reflector.

(NOTE: Alternately, the method described in the Phasor Owners

Manual may be used to achieve a linear screen prescribed in 5.3.2.)

5.3.3. With the Phasor programmed in accordance with table 5.3, adjust the

DbD gain control such that the response from the 0.060hole, when the

search unit is placed at position A from Annex D Drawing 1, is maximized

with the primary testing angle from Table 5.1, to display a resulting

amplitude in the A%A between 40% to 60%. The resulting DbD setting is

the zero reference level and shall be recorded on the Ultrasonic Test

Report Table 7.1 under Reference level (b).

(NOTE: The reference level may also be achieved by using only one side

of the gain in the Phasor. DbA or DbD. In this case toggle the steps key

to display the gain being used in the home screen. To activate the Level

above reference function, press and hold the orange key next to the gain

sub-menu box. In either case it is important to note the sum of all gain

applied above reference.


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Table 5.1


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Table 5.1 (cont.)


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Table 5.2

PROBE MENU

(Sub-menu) (Tab) (Value)

PRB DAT Dialog Probe Load Def

PRB GEO

Frequency 2.3 MHz

Number of Elements 16

Pitch 0.040

Elevation 0.650

WDGE DAT Element 1 Position Low end

WDGE GEO

Velocity .1086 in/s

Wedge Front 0.000

Offset Z 1.00 (Annex C)

Angle 0.0 deg

OFFSET Origin Offset 0.000

PART MENU


PLAN Material Thickness Enter material thickness

CAL as described in section 5.2

SCAN MENU


ELECTRNC

Type Linear

Focal Point Unfocused

Wave Type Longitudinal

SCN PATT

Angle Start 0.0 deg

Angle Stop 0.0 deg

Angle Step 1.0 deg

APERTURE

Number of Steps 1

First Element 1

Aperture Size 16

Aperture Step 1

DISPLAY MENU


VIEW

View Mode Frame

Angle corrected OnData Source Amp A

BACKGRND Color Leg On

RESULTS1

Reading 1 Beam

Readings may bedisplayed in any order

Reading 2 A%A

Reading 3 SA

Reading 4 PA

UT MENU


BaseDisplay Start Material

Display Delay 0.000 in

Leg 2.3

Pulser

Voltage 150V

Width 220ns

PRF Value set to maximum

ReceiverFrequency 2MHz

Ascan Rectify Fullwave

GATEMODE

Gate select Gate A

Logic Positive

Gate Display On


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Table 5.3

PROBE MENU


PRB DAT Dialog Probe Load Def

PRB GEO

Frequency 2.3 MHz

Number of Elements 16

Pitch 0.040

Elevation 0.650

WDGE DAT Element 1 Position Low end

WDGE GEO

Velocity .1086 in/s

Wedge Front 0.711

Offset Z 0.435 (Annex C)

Angle 47.5 deg

OFFSET Origin Offset 0.000

PART MENU


PLAN Material Thickness Enter material thickness

CAL as described in section 5.3

SCAN MENU


ELECTRNC

Type Sector


Wave Type Shear

SCN PATT

Angle Start 35.0 degminimum

Angle Stop 70.0 deg

Angle Step 1.0 deg

APERTURE

Number of Steps 1

First Element 1

Aperture Size 16

Aperture Step 1

DISPLAY MENU


VIEW

View Mode Frame

Angle corrected OnData Source Amp A

BACKGRND Color Leg On

RESULTS1

Reading 1 Beam

Readings may be

displayed in any order

Reading 2 A%A

Reading 3 SA

Reading 4 PA

UT MENU


BaseDisplay Start Material

Display Delay 0.000 in

Leg 2.3

Pulser

Voltage 150V

Width 220ns

PRF Value set to maximum

ReceiverFrequency 2MHz

Ascan Rectify Fullwave

GATEMODE

Gate select Gate A

Logic Positive

Gate Display On


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6. Examination

6.1.General

6.1.1. An X line for flaw location shall be marked on the test face of the

weldament in a direction parallel to the weld axis. The location distance

perpendicular to the weld axis is based on the dimensional figures on the

detail drawing and usually falls on the centerline of the butt welds, and

always falls on the near face of the connecting member of T and corner

welds, the face opposite Face C. (see Table 5.1 for Face descriptions.)

6.1.2. A Y accompanied with a weld identification number shall be clearlymarked on the base metal adjacent to the weld being examined at the left

end on Face A (see Table 5.1 for Face descriptions.) This identification

number serves as:

a) Weld identification,

b) Identification of Face A,

c) Distance measurements and direction (+ or -) from the X line,

d) Location measurements from weld ends or edges.

6.1.3. A couplant described in 4.4 shall be used between the search unit and

scanning surface.

6.1.4. All surfaces to which the search unit(s) is applied shall be free of weld

spatter, dirt, grease, oil, paint, loose scale, or any material/condition which

would prevent the transmission of ultrasound, and shall have a contour

allowing intimate coupling.


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6.2.Base metal examination

6.2.1. The entire volume of base metal through which ultrasound must travel to

examine the weld shall be examined for laminar reflectors utilizing the

straight beam search unit calibrated in section 5.2. If any area of base

material exhibits a total loss of back wall reflection or displays an indication

equal to, or greater than the original back wall reflection height, and is

located such that its presence will interfere with the transmission of the

ultrasound for the weld inspection, its size, location, and depth from the A

Face shall be determined and reported on the ultrasonic test report, and an

alternate weld scanning procedure shall be used.

6.2.1.1. When the indication is larger than the search unit a full loss of theback wall reflection will usually occur. By sliding the search unit off

the indication until a 50% drop in amplitude from the indication is

realized, and then by measuring to the centerline of the search

unit, is generally reliable for determining the edges of the

indication.

6.2.1.2. The size evaluation of an indication which is smaller than the

search unit must be made by sliding the search unit toward theindication until a signal begins to form. At this point, the leading

edge of the search unit is indicative of the edge of the indication.

6.2.2. If all or part of the weld is deemed inaccessible due to laminar

indications, and cannot be examined in accordance with the

requirements of table 5.1, the examination shall be conducted using one

or more of the following alternate procedures, as necessary, to attain full

weld coverage.

a) Weld surfaces shall be ground flush in accordance with the

applicable paragraph(s) of the code,

b) Test from Faces A and B,

c) Utilize alternate search angles.


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6.3. Weld examination

6.3.1. Welds shall be tested with the search unit described in Section 4.2, and

calibrated in Section 5.3. Following calibration, and during testing, the

only instrument adjustment permitted is the sensitivity level (gain)

setting.

6.3.1.1. Sensitivity shall be increased from the reference level to scanning

level in accordance with scanning levels described in Table 7.5A,

or 7.5B as applicable.

6.4. Scan patterns (see Figure 6.4)

6.4.1. It is intended as a minimum that all welds are to be examined by passingsound through the entire volume of the weld and HAZ in two crossing

directions, wherever practical.

6.4.2. All butt welds shall be examined from each side of the weld axis. Corner

and T welds shall be primarily tested from one side of the weld axis only.

All Welds shall be examined using the applicable scanning pattern, or

patterns as shown in Figure 6.4, as necessary to detect both longitudinal

and transverse discontinuities.

6.4.3. To detect longitudinal defects, the following movements may be

combined from figure 6.4

6.4.3.1. Scanning Movement A, Rotation angle a = +/-10deg.

6.4.3.2. Scanning Movement B, Scanning Distance b shall be such that

the full section of the weld is being examined with the primary

angle from Section 5.3.

6.4.3.3. Scanning Movement C, Progression Distance c shall be

approximately one half the array width.

6.4.4. To detect transverse defects, cover the full weld section with one of the

following movements from Figure 6.4


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6.4.4.1. Scanning pattern D, when weld reinforcement is ground flush.

6.4.4.2. Scanning Pattern E, when weld reinforcement is not ground

flush. Scanning Angle e = 15deg. maximum.

6.4.5. For electroslag or electrogas welds, use Scanning Pattern E, with the

search unit rotation angle e between 45deg. to 60deg.


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Table 6.4

Scanning Patterns


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7. Indication Evaluation and Reporting

7.1. When a discontinuity indication appears on the screen, the maximum

attainable reflection from the indication shall be adjusted to produceamplitude equivalent to the horizontal reference level (set in Sec. 5.3.3.).

The instrument reading in dB shall be used as the Indication Level, a, for

calculating the Indication Rating, d, as shown in the ultrasonic test report

Fig 7.1.

7.2. The Attenuation Factor, c, in the ultrasonic test report shall be attained by

subtracting 1 inch of sound path (SA in the results window) from the

distance to the indication and multiplying the remainder by 2, and rounded to

the nearest dB value.

7.3. The Indication Rating, d, in the ultrasonic test report represents the

algebraic difference in decibels between the indication level with correction

for attenuation as indicated by the following expression:

Gain in dB: ac =d

(Use: abc = d if the method noted under 5.3.3. is being used)

NOTE: Traditionally the indication level a is the sum of all gain applied. For

the purpose of this document the indication level is expressed as the amount of

gain OVER the reference gain. Therefore the equation will be a c = d, and

NOT a bc = d

7.4. Lengths of indications with ratings more severe than Class D shall be

determined by measuring the distance between the transducer centerline

locations where the indication drops 50% in amplitude (6dB) below the

rating for the applicable flaw classification. The length shall be recorded as

discontinuity length on the ultrasonic test report.


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7.5. Each weld discontinuity shall be accepted or rejected on the basis of its

indication rating, and its length in conformance with the applicable Table

7.5A or 7.5B. Only those indications that are found to be unacceptable need

be recorded on the test report. The exception being those welds identified in

the contractual documents as being fracture critical. Fracture critical welds,

which are within 6dB inclusive of the minimal unacceptable rating, shall be

included on the test report.

7.6. Each unacceptable discontinuity shall be indicated on the weld by a mark

directly over the discontinuity for its entire length. The depth from the

surface and indication rating shall be clearly noted on the adjacent basemetal.

7.7. Retesting of welds that have been repaired shall be documented on a new

line in the ultrasonic report, if the original is used, and shall be designated by

an R prefix in the indication number. If additional report forms are used, the

R designation shall prefix the report number, and / or the weld number, or

any such manner that clearly identifies the weld as being previously

repaired.


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Table 7.1

Ultrasonic Report Form


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Table 7.5A

AWS D1.1 STRUCTURAL WELDING CODE STEEL

UT ACCEPTANCE-REJECTION CRITERIA (Statically Loaded Nontubular Connections)


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Table 7.5B

AWS D1.1 STRUCTURAL WELDING CODE STEEL

UT ACCEPTANCE-REJECTION CRITERIA (Cyclically Loaded Nontubular Connections)


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Annex A

dB accuracy procedure

1.dB Accuracy Procedure.

Note: In order to attain the required accuracy (+ 1%) in reading the indicationheight, the Display must be graduated vertically at 2% intervals at horizontalmidscreen. These graduations shall be placed on the Display between 60%and 100% of screen height. This may be done with use of a graduatedtransparent screen overlay. If this overlay is applied as a permanent part ofthe ultrasonic unit, care should be taken that the overlay does not obscurenormal testing displays.

(1) Program the Phasor in accordance with Table 5.2. Thencouple the straight beam search unit to the block shown inDrawing D.1 and position "T".

(2) Adjust the distance calibration so that the first 2 inch backreflection indication (hereafter called "the indication") is athorizontal mid-screen.

(3) Adjust the calibrated gain or attenuation control so that the

indication is exactly at or slightly above 40% screen height.(NOTE: the pulser voltage may be turned down if the gainvalue will not go low enough to establish a 40% value.)

(4) Move the search unit toward position U, until the indicationis at exactly 40% screen height.

(5) Increase the sound amplitude 6dB with the calibrated gainor attenuation control. The indication level theoreticallyshould be exactly 80% screen height.

(6) Record the dB reading under "a" and actual % screenheight under "b" from step 5 on Line 1 of the "UltrasonicUnit Calibration Report", Form A.1 of this annex.

(7) Move the search unit further toward position U, until theindication is exactly 40% screen height.

(8) Repeat step 5.


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(9) Repeat step 6. Except, information should be applied tothe next consecutive line on the "Ultrasonic Unit CalibrationReport", Form A.1.

(10) Repeat steps 7, 8 and 9 consecutively until the full range of

the gain control or attenuator is reached (60 dB minimum).

(11) Apply the information from Rows "a" and "b" to the belowreferenced equation (Section 2. Annex A) or thenomograph (Form A.2) to calculate the corrected dB.

(12) Apply corrected dB from step 11 to Row "c".

(13) Subtract Row "c" value from Row "a" value and apply thedifference in Row "d", dB error. These values may beeither positive or negative and should be noted with a plus

sign "+" or a minus sign "-".

(14) Information shall be tabulated on a form, includingminimum equivalent information as displayed on the"Ultrasonic Unit Calibration Report" (Form A.1) and the unitevaluated in accordance with instructions shown on thatform.

(15) Form A.2 provides a relatively simple means of evaluatingdata from item (14). Instructions for this are given in (16)through (18) below.

(16) Apply the dB information from Row "e" (Form A.1) verticallyand dB reading from Row "a" (Form A.1) horizontally as Xand Y coordinates for plotting a dB curve on Form A.2.

(17) The longest horizontal length, as represented by the dBreading difference, which can be inscribed in a rectanglerepresenting 2 dB in height, denotes the dB range in whichthe equipment meets the Code requirements. Theminimum allowable range is 60 dB.

(18) Equipment that does not meet this minimum requirementmay be used, provided correction factors are developedand used for discontinuity evaluation outside the instrumentacceptability linearity range, or the weld testing and thediscontinuity evaluation is kept within the acceptablevertical linearity range of the equipment.

Note: The dB error figures (Row d) may be used ascorrection factor figures.


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2. Decibel Equation.The following equation shall be used to calculate decibels:

dB1 = Row a

dB2 = Row c

%1 = Row b

%2 = Is the average of Row b disregarding the first andlast three tabulations

dB+%

%x20=dB 1

1

2

2

log


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Form A.1

Ultrasonic Unit Calibration Report Form

Ultrasonic Unit Model: Serial No.:

Search Unit - Size: Type: Frequency: MHZ

Calibration - Date: Interval: 2 Months Method:

Block Serial No.: Data: As Found As Adjusted

Supplemental Instructions:

Start with the lowest dB level that you can obtain a 40 percent display height indication from. Add 6 dB's andrecord this dB reading in Row A and display height Row B as the starting points on the tabulation chart.

After recording these values in Rows A and B, slide the transducer to obtain a new 40 percent display

height. Without moving the transducer add 6 dBs and record the new dB reading and the new display height inRows A and B. Repeat this step as many times as the unit allows.

Find the average % screen values from Row B by disregarding the first 3 and the last 3 tabulations. Usethis as %2in calculating the corrected reading.

The following equation is used to calculate rowc:

%1 is Row B

%2 is the average of Row B disregarding thefirst and last three tabulations.

dB1is Row A

dB2is Row C

The dB Error "Row D" is established by subtracting Row C" from Row A": (A - C = D).

The Collective dB Error "Row E" is established by starting with the dB Error "Row D" nearest to 0.0,collectively add the dB Error Row D values horizontally, placing the sub-totals in Row E".

Moving horizontally, left and right from the Average % line, find the span in which the largest and smallestCollective dB Error figures remain at or below 2 dB. Count the number of horizontal spaces of movement,subtract one, and multiply the remainder by six. This dB value is the acceptable range of the unit.

In order to establish the acceptable range graphically, Form D-9 from AWS D1.1 may be used as follows:

(1) Apply the collective dB Error Row E values vertically on the horizontal offset coinciding with the dB readingvalues from "Row A".

(2) Establish a curve line passing through this series of points.

(3) Apply a 2 dB high horizontal window over this curve positioned vertically so that the longest section iscompletely encompassed within the 2 dB Error height.

(4) This window length represents the acceptable dB range of the unit.

dB+%

%x20=dB 1

1

2

2

log


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Ultrasonic Unit Calibration Report Form A.1 (cont.)

NUMBER 1 2 3 4 5 6 7 8 9 10 11 12 13

Row A dB READING

Row B DISPLAY HEIGHT

Row C CORRECTED READING

Row D dB ERROR

Row E COLLECTIVE dB ERROR

Accuracy Required: Minimum allowable Range is 60 dB. %2(Average) %

Equipment is: Acceptable for Use Not Acceptable for Use Recalibration Due Date:

Total qualified range dB to dB = dB Total error dB (From the Chart above)

Total qualified range dB to dB = dB Total error dB (From AWS Form D-9)

Calibrated by: Level: Location:


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Form A.2

dB Accuracy Evaluation Report Form

Ultrasonic Unit Model: Serial No.:

Search Unit - Size: Type: Frequency: MHZ.


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Annex B

Horizontal Linearity, Internal Reflectors, and Resolution

1. Horizontal Linearity Procedure.1.1 This qualification procedure is performed with the straight beam

search unit, which produces longitudinal wave with a sound velocityof almost double that of shear wave. It is necessary to double theshear wave distance ranges to be used in applying this procedure.Example:

The use of a 10 in. [250 mm] screen calibration in shear wave wouldrequire a 20 in. [500 mm] screen calibration for this qualification procedure.

The following procedure shall be used for instrument certification:

(1) Couple a straight beam search unit meeting the requirementsof paragraph 4.2 to the DS block (Drawing D.1 in Position U).

(2) To attain a 20 in. [500 mm] screen calibration, adjust the firstand fifth back reflections to their proper locations with use ofthe distance calibration and zero delay adjustments.

(3) Each indication shall be adjusted to reference level with thegain or attenuation control for horizontal location examination.

(4) Each intermediate trace deflection location shall be correctwith +2% of the screen width. With the display width at 20 in.[500 mm] the +2% would be equivalent to +.400 in. [10 mm].

2. Internal Reflections Procedure.(1) Calibrate the equipment in accordance with 5.3

(2) Remove the search unit from the calibration block withoutchanging any other equipment adjustments.

(3) Increase the calibrated gain or attenuation 20 dB more

sensitive than reference level.

(4) The screen area beyond 1/2 in. [12 mm] sound path andabove reference level height shall be free of any indication.


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3. Resolution Requirements.3.1 The combination of search unit and instrument shall resolve three holes

in the RC resolution reference test block shown in Drawing D.1, or D.3.The search unit position(s) from Drawing D.1 are as follows:

(1) The 45 degree shall be placed at position S.

(2) The 60 degree shall be placed at position R.

(3) The 70 degree shall be placed at position Q.

3.2 The resolution shall be evaluated with the instrument controls set atnormal test settings and with indications from the holes brought tomidscreen height. Resolution shall be sufficient to distinguish at least

the peaks of indications from the three holes. Use of the RC resolutionreference block for calibration shall be prohibited. Each combination ofinstrument search unit (shoe and transducer) shall be checked prior toits initial use. This equipment verification shall be done initially witheach search unit and UT unit combination. The verification need not bedone again provided documentation is maintained that records thefollowing items:

(1) UT machines make, model and serial number.

(2) Search units manufacturer, type, size, angle, and serial

number.

(3) Date of verification and technicians name.


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Form B.1

Ultrasonic Unit Calibration Report Form B.1

Ultrasonic Unit Model: Serial No:

Search Unit - Size: Type: Frequency: MHZ

DS Block Serial No: Calibration Interval: 40 hours use

Horizontal linearity :

INDICATION

NUMBER

LOCATION ACCEPTABLE

RANGE

ACTUAL

LOCATION

1 4.0" 3.6 to 4.4

2 8.0" 7.6 to 8.4

3 12.0" 11.6 to 12.4

4 16.0" 15.6 to 16.4

5 20.0" 19.6 to 20.4

Internal Reflections:

IIW Block SN: Reference Level: dB

Remove search unit from block without changing any equipment settings

Increase the calibrated gain 20 dB more sensitive than reference level

Is the CRT screen area beyond 1/2" sound path and above reference level height free of

any indications? Yes: No:___

Equipment Status:

As Found As Adjusted

Not Acceptable for Use Acceptable for Use

Calibrated By: Level: Date:_____________

Reviewed By: Location:____________________


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Form B.2

Ultrasonic Unit Resolution Report Form B.2

Ultrasonic Unit Model: Serial No:___________________________

IIW Block Serial No: Resolution Block Serial No:_____________

RESOLUTION REQUIREMENTS:

Longitudinal Mode - Transducer and instrument shall resolve all 3 distances

Shear Wave Mode - Transducer and instrument shall resolve the 3 test holes

TRANSDUCERS:

Serial No. Size Type Frequency Angle(s)

Equipment is: Acceptable for Use Not Acceptable for Use_________

Performed By: Level: __ Date:_________

Reviewed By: Location:_____________________


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Annex C

Search unit check

1. This annex is written as a supplemental document to support this procedure anddescribes the method(s) to perform the following:

1) Transducer element, cable, and coupling check.2) Calculate the Z offset.

2. Due to the proximity of each element in relation to the face of the wedge (e.g. the1stelement is closer to the bottom of the wedge than the last due to the slope of the

angle.) each individual element will have a different delay in succession fromlowest to highest. To display this, program the Phasor according to the table in thisannex.2.1. Elements that do not produce a response are dead elements.

2.1.1. The number of dead elements shall not exceed more than 3 total in thearray, and no more than 2 adjacent for the array to be consideredacceptable.

2.1.2. Poor coupling will display a decrease, or lack of sound transmissionthrough all or part of the wedge. In this case remove the wedge, andre-couple the probe.

2.2. Elements that do produce a response, but appear out of sequence, or

otherwise not in line with the rest of the slope, are wired incorrectly and notfiring in the proper sequential order.


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PROBE MENU

(Sub-menu) (tab) (value)

Probe GeometryNumber of elements 16

Pitch 0.040Wedge Dat Elem 1 Pos Low End

Wedge GeometryOffset Z 0

Angle 0

Offset Probe Delay 0.000s

PART MENU


Part Velocity L .1080 in/us

SCAN MENU


Electronic

Type Linear


Wave Type Longitudinal

Scan Pattern Angle Start 0.0 deg

Aperture

Number of Steps 16

First Element 1

Aperture Size 1

Aperture Step 1

DISPLAY MENU


View Angle Corrected On

Results1

Reading 1 P%A

Reading 2 PSA

Reading 3 Beam

Reading 4 SA

UT MENU


Base Display Delay 0.0

Pulser

Voltage 150V

Width 220ns

Receiver Frequency 2MHz

Gate mode TOF mode Flank


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Results for a 1D probe

The pattern created is the result of firing each individual element in sequence,and the step like slope that is created is due to the different thickness inwedge material, or delay, beneath each element.


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3. Determining the Z Offset.

Material thickness and leg functions must be adjusted to your wedge in orderto display the step pattern on the screen.

The A gate must frame the wedge echoes.

The gain must be high enough so that the P%A reading is the result of thefirst element being barely > 100% FSH.

Position the beam cursor to the last element so that it is reading in the SA.

For formulas use:

D1 = delay of first element (PSA)D2 = delay of last element (SA)N = number of elements

To determine the Z offset:

Z offset = (D1 + D2) / 2

1) Z = (9.14mm + 13.60mm) /22) Z = (22.74mm) /23) Z = 11.37mmSpecified value 11.5mm Measured value 11.37mm


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Annex D

Drawings

Drawing D.1


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Drawing D.2


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Drawing D.3


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Drawing D.4

AWS Procedure - Rev 2.pdf

Documents