procedure for ut

8/12/2019 Procedure for UT

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LARSEN & TOUBRO LIMITEDPAGE NO.- 1 OF 11

DATE:-05..11.07MSQ UP GRADATION (EPCC 1)

PROJECT REV.NO.- 0

PROCEDURE FOR ULTRASONIC

TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

CONTENTS:

1.0 PURPOSE

.0 SCOPE

!.0 REFERENCES

".0 INSPECTION PERSONNEL

5.0 UT EQUIPMENTS

#.0 CALIBRATION FOR TESTING

7.0 TESTING PROCEDURE

$.0 ACCEPTANCE & REJECTION CRITERIA

%.0 ATTACMENTS.

APPROVED B' L & T REVIEED APPROVED B' JACOBS


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PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

1.0 PURPOSE:

The purpose of this procedure is to provide sufficient guidelines to operators,

examiners, inspectors, and engineers etc. to apply ULTRASONIC TEST method

correctly and efficiently as a Non-Destructive Test tool for determination of

discontinuities in welds.

.0 SCOPE:

The Scope of this procedure covers all structural steel column welds !uild-up

Sections" which are li#ely to $e fa$ricated at %o$ site&shop of 'S( )p gradation

*ro%ect, *anipat +efinery, *anipat, aryana. This procedure will $e valid for *late-to-

*late welded %oint only. Thic#ness of structural mem$ers varies from mm to /

mm. 'aterial Spec 0 1S 232 4r. 5&!. 6 1S 22 4r. 11

3.0 REFERENCE:

57S D., Sec 3

SNT-T8-5 of 5SNT.

4.0 INSPECTION PERSONNEL

)ltrasonic Testing shall $e performed $y NDT 9evel 11 personnel in accordance with

SNT-T8-5. NDT :ualification shall include demonstration of a$ility to apply the rules

of the 57S D . code in the accurate detection and disposition of discontinuities.

5.0 UT EQUIPMENTS

5.1 Basic Unit

The )T e:uipment shall $e the pulse echo type suita$le for use with transducers

oscillating at fre:uencies $etween and 3 ';. The display shall $e an 5 scan

rectified video trace.



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PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

The ori;ontal linearity of the test instrument shall $e :ualified over the full sound

path distance to $e used in testing in conformance with 3. and shall $e

chec#ed for correct cali$ration at 2 month intervals in conformance with 3. '; shall $e used.

5.2.1 T"PE OF SEARC! UNITS

5.2.1.1Straight $eam 9ongitudinal wave" search unit transducers shall have an active area

of mm dia crystal si;e.

5.2.1.25ngle $eam search units crystal shall $e ? x @ mm rectangular. The search unit shall

produce a sound $eam in the material $eing tested within plus or minus 2 o. 1f one of

the following proper anglesA Bo, 3oor >/o. The dimensions of the search unit shall

$e such that distance from the leading edge of the search unit to the index point shallnot exceed .

5.3 R#s$%&ti$n

Cor straight $eam search unit, the transducer shall $e set in position C= on the 117

$loc# as specified in the 57S D.. Transducer and instrument shall resolve all three

distances. Cor angle $eam search unit, +8 $loc# shall $e used as per clause no.

[email protected]./.

5.4 Int#'na% R#(%#cti$n:

5ngle $eam search unit shall meet the criterion of clause 3.2>. hours of instrument use as

per clause 3.


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PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

5.4 *ro$e *arameters

T)*# Si+#

oNormal $eam *ro$e mm dia

5ngle *ro$e

>/o, 3o, Bo5ngle pro$e ?mm E @mm crystal

Cre:uency of pro$es 2'; to >';.

,.0 CALIBRATION FOR TESTIN-

,.1 Ca%i'ati$n $( Bas# Unit

The detector until shall $e cali$rated $y an approved Third party yearly or after any

ma%or repair or service done to the e:uipment. 1n addition to this, the e:uipment

:ualification shall $e performed as per 57S D . clauseFFFFF.

5ll cali$rations and tests shall $e made with the re%ect control turned off.

,.2 /ai%) Ca%i'ati$n T#sts

The Gperator shall carry out and #eep record of daily cali$ration chec#s of the

followingA

Time-$ase linearity

4ain

Sensitivity

*ro$e 1ndex8ali$ration of 5ngle !eam search units shall $e done with the use of an approved

cali$ration $loc#, each angle-$eam search unit shall $e chec#ed after each eight

hours of use to determine that the contact face is flat, the sound entry point is correct

and the $eam angle is within allowed tolerance.



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PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

,.3Ca%i'ati$n $( Ti# Bas#

Time $ase and range cali$ration shall $e set to accurately cover the entire ultrasonic

$eam distance for each pro$e selected for examination of the sample, using $asic

cali$ration $loc#s with artificial or defect reflectors at the commencement of each %o$

or pro$e change. The cali$ration shall $e chec#ed fre:uently throughout the

examination.

,.4R#(#'#nc# Ca%i'ati$n B%$cs

The 1nternational 1nstitute of 7elding 117 0 H 6 H2" )T reference $loc# shall $e the

standard used for $oth distance cali$ration and 117 0 H $loc# shall $e used for

sensitivity cali$ration. Gther porta$le $loc#s may $e used provided the reference

level sensitivity for instrument & search unit com$ination shall $e ad%usted to $e the

e:uivalent of that achieved with the 117 $loc#. The use of a corner reflector for

cali$ration purpose shall $e prohi$ited.

,.5B#a In# ($' An%# P'$#

The angle pro$e is positioned in the H $loc# to o$tain maximum echo for mm

radius. The index point is verified with the mar#ing in the cali$ration $loc#.

,.,St'ait B#a Ca%i'ati$n

S6##* 7 The hori;ontal sweep shall $e ad%usted for distance cali$ration to present

the e:uivalent of at least two plate thic#nesses on the display.

S#nsiti8it) 7 The sensitivity shall $e ad%usted at a location free of indications so thatthe first $ac# reflection will $e / to B/I of full screen height.

,.9An%# B#a Ca%i'ati$n

S6##* 7 The hori;ontal sweep distance shall $e ad%usted to represent the actual

sound path distance $y using the 117 $loc#.

The distance cali$ration shall $e made using either the / in /2mm" scale or 1n.

2/mm" scale on the display, whichever is appropriate. 1f, however, the %oint



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PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

configuration or thic#ness prevents full examination of the weld at either of these

settings, the distance cali$ration shall $e made using / in. or 2 in. >mm or

/mm" scale as re:uired.

A*%it $' S#nsiti8it) 7 The Transducer shall $e set in a position on the 117 H

$loc# to the indication from the ./mm hole to attain a hori;ontal reference-line height

indication. The maximum deci$el reading o$tained shall $e used as the R#(#'#nc#

L#8#%. .

8ali$ration for sensitivity and hori;ontal sweep shall $e made $y the )T operator %ust

prior to and at the location of testing each weld.

+ecali$ration shall $e made after a change of operators, each


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PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

+eferencing code section

,.


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PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

5nnex " shall $e determined and reported on the )T report, and an alternate weld

scanning procedure shall $e used.

9.3. Inicati$n L#8#% >a?

7hen a discontinuity indication appears on the screen, the maximum attaina$le

indication from the discontinuity shall $e ad%usted to produce a hori;ontal reference

level trace deflection on the screen. The ad%ustment shall $e made with the cali$rated

gain control, and the instrument reading in deci$els shall $e used as the Inicati$n

L#8#%@ a?@ for calculating the Inicati$n Ratin@ ?.

9.4 Att#n&ati$n Fact$'@ c

The 5ttenuation factor, c shall $e attained $y su$tracting in. 2/mm" from the

sound path distance and multiplying the remainder $y 2. This factor shall $e rounded

out to the nearest d! value.

9.5 Inicati$n Ratin@ .

The 1ndication +ating, d represents the alge$raic difference in deci$els $etween the

indication level and the reference level with correction for attenuation as indicated in

the following expressionsA

1nstruments with gain in d!A a 0 $ 0 c L d.

9., Basis ($' Acc#*tanc# $' R##cti$n.

Jach weld discontinuity shall $e accepted or re%ected on the $asis of its indication

rating and its length in conformance with 5cceptance 8riteria mentioned. Gnly thosediscontinuities which are unaccepta$le need $e recorded on the test report.

9.9Si+# E8a%&ati$n P'$c#&'#

St'ait B#a T#stin 7 The approximate si;e evaluation of the reflector shall $e

made $y $eginning outside of the discontinuity and moving the transducer toward the

area of the discontinuity until the indication on the display $egins to form. The leading

edge of the search unit at this point is indicative of the edge of the discontinuity.



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PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

An%# B#a T#stin 7 The following procedure shall $e used to determine lengths

of indications which have d!ratings more serious than for a 8lass D indication as per

5cc 8riteria. The length of such indication shall $e determined $y measuring the

distance $etween the transducer centreline locations where the indication rating

amplitude drops /I 3d!" $elow the rating for the applica$le discontinuity

classification.

9.; Inacc#ssii%it)

1f part of a weld is inaccessi$le to testing with the re:uirements mentioned in the

ta$le 3.B of 57S D. due to laminar content, the testing shall $e conducted using

one or more of the following alternative procedures as necessary to attain full weld

coverage.

7eld surfaces" shall $e ground flush

Testing from !oth sides. Cace 5 6 Cace !"

Gther search unit angles shall $e used.

Gther scanning patterns can also $e used. See sr. no. < of 5nnex "

;.0 ACCEPTANCE REECTION CRITERIA

The applica$le 5cceptance 6 re%ection criterion is as per Ta$le 3.< of 57S D..

See attachment".


10/11

Single side scanning f! Single "

60#$%% &in% $' % F$ll #ea(

'a%) *1 "+

,$-le side scanning f! ,$-le " 60

#$%% &in%. U' % )alf -e( 'a%) n -%)

sides * "+



PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

ANNE 1 D /#tai%s $( $ Ticn#ss@ =#% $ints@ an Scannin *att#'ns #t$s.

1. F$' $ Ticn#ss 10 12. An%# $( P'$# 7 90$@ F'#. $( P'$# 7 2M!+.

2. F$' $ Ticn#ss 20@ 25 32D. An%# $( P'$# 7 90$@ F'#. $( P'$# 7 2M!+.


Face #

Face

F$ll #ea( Pa%) *1 "+ alf #ea( 'a%) * " 'a%)+


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PROJECT REV.NO.- 0


TESTING

PROCEDURE NO.-

LT/MSQ/P/UT/011

3. =#n t# =# *%at# $int (itt# 6it F%an# *%at#@ Scannin t$ # $n# as *#' t#

#%$6 s#tc ($' 6# (%an# $inin a'#a.


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