GE MFE DMS 2 User manual

Krautkramer DMS 2 / 2E
Operating Manual
GE
Inspection Technologies Ultrasonics
www.ge.com/inspectiontechnologies

DMS 2/DMS 2E
Operating Manual
GE Inspection Technologies Ultrasonics
Ident-Nr. 021-002-151, Rev. H

THIS PAGE
INTENTIONALLY BLANK

Important Notice
DMS 2 Operating Manual Page iii
Important Notice
The following information must be read and understood by any
user of a Krautkramer ultrasonic thickness gauge. Failure to
follow these instructions can lead to errors in thickness mea-
surements or other test results. Decisions based on erroneous
results can, in turn, lead to property damage, personal injury or
death.
General Warnings
Proper use of ultrasonic test equipment requires three essential
elements:
• Selection of the correct test equipment.
• Knowledge of the specific “test application requirements.”
• Training on the part of the instrument operator.
This operating manual provides instruction in the basic set up
and operation of the Krautkramer thickness gauge. There are,
however, additional factors which affect the use of ultrasonic
test equipment. Specific information regarding these additional
factors is beyond the scope of this manual. The operator
should refer to textbooks on the subject of ultrasonic testing for
more detailed information.
Operator Training
Operators must receive adequate training before using ultra-
sonic test equipment. Operators must be trained in general
ultrasonic testing procedures and in the set up and perfor-
mance required by a particular test. Operators must under-
stand:
• Soundwavepropagationtheory.
• Effects of the velocity of sound of the test material.
• Behavior of the sound wave where two different materials
are in contact.
• Areas covered by the sound beam.
More specific information about operator training, qualification,
certification, and test specifications is available from various
technicalsocieties,industrygroups,andgovernmentagencies.
Testing Limitations
In ultrasonic testing, information is obtained only from within the
limits of the sound beam. Operators must exercise great caution
in making inferences about the test material outside the limits of
the sound beam. For example, when testing large materials it
may be impossible or impractical to inspect the entire test piece.

Important Notice
Page iv DMS 2 Operating Manual
When a less-than-complete inspection is to be performed, the
operator must be shown the specific areas to inspect. Infer-
ences about the condition of areas not inspected, based on
data from the evaluated areas, should only be attempted by
personnelfullytrainedinapplicablestatisticalandprobability
techniques. In particular, materials subject to erosion or
corrosion,inwhichconditionscanvarysignificantlyinanygiven
area, should only be evaluated by fully trained and experienced
operators.
Sound beams reflect from the first interior surface encoun-
tered. Because of part geometry and overlapped flaws or
overlapped surfaces, thickness gauges may measure the
distance to an internal flaw rather than to the back wall of the
material. Operators must take steps to ensure that the entire
thickness of the test material is being examined.
Ultrasonic Thickness Measurement Critical Operating
Procedures
The following operating procedures must be observed by all
users of ultrasonic thickness gauges in order to minimize errors
intestresults.
1.
Calibration of Sound Velocity
The principle of operation of an ultrasonic thickness gauge is
that the instrument measures the time of flight of an ultrasonic
pulse through the test piece and multiplies this time by the
velocity of sound in the material. Thickness measuring error is
minimized by ensuring that the sound velocity to which the
instrument is calibrated is the sound velocity of the material
being tested. Actual sound velocities in materials often vary
significantly from the values found in published tables. In all
cases, best results are obtained if the instrument is calibrated
on a velocity reference block made from the same material as
the test piece; this block should be flat and smooth and as thick
as the maximum thickness of the test piece.
Operators should also be aware that the sound velocity may
not be constant in the material being tested; heat treating, for
example, can cause significant changes in sound velocity. This
must be considered when evaluating the accuracy of the
thicknessprovidedbythisinstrument. Instrumentsshould
always be calibrated before testing, and the calibration should
be checked after testing, to minimize testing errors.

Important Notice
DMS 2 Operating Manual Page v
2. Probe Zero Procedure
The probe zero procedure must be performed as described in
this manual. The probe zero block should be clean, in good
condition, without noticeable wear. Failure to properly perform
the probe zero procedure will cause inaccurate thickness
readings.
3.
Effects of Temperature on Calibration
Temperature variations change the sound velocity of materials
and transducer delay lines and, therefore, calibrations. All
calibrations should be performed on-site, and with test blocks
at the same temperature as the test piece, to minimize errors
due to temperature variations.
4.
Transducer Selection
The transducer used in testing must be in good condition
without noticeable wear of the front surface. Badly worn
transducers will have a reduced effective measuring range.
The specified range of the transducer must include the com-
plete range of thicknesses to be tested. The temperature of
the material to be tested must be within the transducer’s
temperature range.
5.
Use of Couplants
Operators must be familiar with the use of ultrasonic couplants.
Testing skills must be developed so that couplant is used and
applied in a consistent manner to minimize variations in
couplant layer thickness and errors in test results. Calibration
and actual testing should be performed under similar coupling
conditions, using a minimum amount of couplant and applying
consistentpressureonthetransducer.
6.
Doubling
Ultrasonicthicknessgaugeswill,undercertainconditions,
display readings which are twice (or, in some cases, three
times) the actual material thickness being measured. This
effect, commonly known as “doubling,” can occur below the
minimum specified range of the transducer. If the transducer
being used is worn, doubling is possible at a thickness greater
than the minimum of the specified range.
When using a new transducer, any reading which is less than
twice the minimum specified range of the transducer may be a
“doubled” reading, and the thickness of the material being
tested should be verified by the use of other methods. If the
transducer shows any sign of wear, doubling may occur at a

Important Notice
Page vi DMS 2 Operating Manual
thickness greater than twice the minimum of the specified
range. This thickness should be determined by calibrating the
instrument/transducer combination on reference blocks that
represent the complete range of possible thicknesses that may
be encountered in testing. This is particularly important when
the test piece is being ultrasonically measured for the first time
or in any case where the history of thickness of the test
specimenisunknown.

Table of Contents
DMS 2 Operating Manual Page vii
Contents
................................................................................... Page
1. Getting Started................................................................ 1
1.1 How To Use This Manual..........................................1
1.2 Ten Steps to Launch Your Gauge............................. 1
1.3 How the DMS 2 Measures Thickness .................... 14
1.4 Important Features of the DMS 2 ...........................19
1.5 What’s in this Manual.............................................. 20
2. Understanding the DMS 2 Keyboard, Menu
System, and Displays ...................................................22
2.1 Recognizing Displays ............................................. 22
2.2 Menu System.......................................................... 24
2.3 Display Screen Features ........................................35
2.4 Keypad Features .................................................... 43
3. Setting Up the DMS 2..................................................... 45
3.1 BatteryInstallation .................................................. 45
........................................................................... Page
3.2 InitialInstrument Setup ...........................................46
3.2.1 DisplayAdjustment ..................................... 48
3.2.2 GlobalSettings ........................................... 50
3.2.3 OPER (Operation) Settings ........................ 52
3.3 Thickness Gauging Setup ......................................55
3.3.1 Probe Type/Measurement Mode
Specification ...............................................55
3.3.2 ALARMSettings .........................................62
3.3.3 Probe Zeroing Procedures .........................65
3.3.4 Calibration Procedures............................... 66
3.3.5 Locking the Instrument Settings .................69
3.4 Storing Data in the Data Recorder.......................... 71
3.4.1 Data Recorder Capabilities......................... 71
3.4.2 Building a Master Comment List ( )
and Using the Virtual Keyboard.................. 74

Table of Contents
Page viii DMS 2 Operating Manual
................................................................................... Page
3.4.3 Creating a Data File.................................... 75
3.4.4 Editing the Names of Elevations,
Locations, and other File Content Labels ... 82
3.4.5 Storing A-scans with Thickness
Measurements............................................84
3.4.6 Additional Information on Working with
DataFiles....................................................85
4. Measuring Thickness ................................................... 90
4.1 Working in the Test Mode ....................................... 91
4.1.1 Activatingthe Test Mode............................. 91
4.1.2 Freezing the A-scan Display
(TEST-FREEZE)......................................... 94
4.1.3 Using the Minimum-Capture Mode for
Enhanced Measurement ............................95
4.2 Measuring and Recording Thickness .....................97
4.2.1 Opening an Existing Data File .................... 97
4.2.2 Activating the Test Mode and Storing
Measurements............................................98
4.2.3 Closing a Data File ................................... 101
................................................................................... Page
4.3 Data Enhancement Features................................ 102
4.3.1 Attaching Comments to a Data Point........ 102
4.3.2 Recording Detailed Measurements with a
Micro-Grid................................................. 104
4.3.3 EditingExisting Files with theAppend,
Insert, and Delete Functions..................... 106
4.3.4 Changing the Digital Thickness Display to
Indicate an Uncoupled Probe
(I/O — LAST R) ........................................ 110
4.4 Adjusting theA-scan Display .................................111
4.4.1 How the A-scan Display can be Modified ..111
4.4.2 Adjusting the Instrument’s Gain................ 114
4.4.3 Adjusting Range ....................................... 115
4.4.4 PositioningtheA-scan with DELAY .......... 117
4.4.5 Purpose of the A-gate and B-gate ............ 118
4.4.6 Choosing the Rectification Method ........... 124
4.5 Working with B-scan Thickness Mapping.............126
4.6 Saving, Recalling, Clearing TG Setups
(Parameter Sets) .................................................. 130
............................................................................................

Table of Contents
DMS 2 Operating Manual Page ix
................................................................................... Page
5. Working with Stored Data ...........................................135
5.1 Introduction to the Data Recorder (DR) Mode...... 135
5.1.1 Selecting an Existing Data File ................. 140
5.1.2 Interpreting the DR Mode / RECORD
Submenu Display .....................................140
5.1.3 Closing (De-selecting) a Data File............ 143
5.1.4 Deletinga Data File .................................. 143
5.2 Navigating in the Data Recorder Mode ................ 144
5.2.1 ChangingtheActiveDataFile ..................144
5.2.2 Navigating from Point to Point Within a
DataFile ...................................................145
5.2.3 Moving to a Specific Position Within a
DataFile ...................................................145
5.2.4 Searching for Specific (Tagged)
Attributeswithina Data File ...................... 146
5.2.5 Automatic Advance Features.................... 150
5.2.6 Adjusting the Data Recorder
(NAV Window) Display ............................. 154
5.2.7 Storing and Recalling A-scans.................. 155
c ................................................................................. Page
5.3 Modifying a Data File’s Organization and
Contents ...............................................................156
5.3.1 EditingExisting Files with the Append,
Insert, and Delete Functions..................... 157
5.3.2 Modifying Data File Content Labels and
Notations................................................... 161
5.3.3 Changing Thickness Measurement
Values From the DR Mode .......................163
5.4 SettingThicknessAlarms .....................................164
5.5 Statistical Evaluationof DataFile Contents ..........165
5.6 Checking the Instrument’s Available Memory....... 166
6. Generating Reports, Printing Data, and Connecting
to External Devices..................................................... 167
6.1 Interfacing with External Devices.........................167
6.1.1 Specifying Printers.................................... 167
6.1.2 Connecting to a Personal Computer ........168
6.2 Sending Data Directly to a Printer ........................168
6.3 Generating Reports ..............................................169

Table of Contents
Page x DMS 2 Operating Manual
................................................................................... Page
6.3.1 Selecting the Report Type ........................170
6.3.2 Transmitting a Report ...............................171
7. Specifications..............................................................172
7.1 DMS 2 Specifications............................................ 172
7.2 Probe Specifications............................................. 175
7.2.1 Dual Element Probes................................ 175
7.2.2 Single Element Probes ............................. 177
7.2.3 Recommended probes for the
D-MultiMode ............................................178
8. Application Notes ....................................................... 179
8.1 General Notes ......................................................179
8.1.1 Flaws ........................................................179
8.1.2 Surface Conditions ...................................179
8.1.3 Curved Surfaces....................................... 179
8.2 Thickness Measurement on Hot Test Pieces ....... 180
8.3 Measurement Through Coatings..........................181
8.4 TopCOAT (Measurement Mode) (Optional).......... 184
................................................................................... Page
8.4.1 Specify Topcoat Probe and Measurement
Mode......................................................... 184
8.4.2 Calibrating for T-COAT Measurement
Mode......................................................... 185
8.4.3 Topcoat Probe Zeroing Procedure ........... 186
8.4.4 CalibratingCoating-MaterialAcoustical
Velocity ..................................................... 187
8.4.5 Identifying the Velocity Reference Block... 188
8.5 Auto-V Measurement Mode
8.5.1 Specifying AUTO-V Measurement Mode.. 189
9. Warranty and Worldwide Service ..............................190
Appendixv A: Hardware Assembly Instructions .......... 192
Appendix B. Choosing the File Type .............................. 193
Appendix C: Helpful Hints............................................... 202
Appendix D: Upgrading the DMS 2/DMS 2E
Instrument .........................................................................204
Index................................................................................... 206

1. Getting Started
DMS 2 Operating Manual Page 1
1.1 How To Use This Manual
This manual will explain how to set up and operate the DMS 2
and DMS 2E Ultrasonic Thickness Gauges. We suggest that
you start by reviewing this introductory “Getting Started”
chapter. It outlines the most important features of the instrument,
explains what you’ll need to know to initially set up your instru-
ment, and introduces the basic steps to follow when recording
data. This chapter also explains how to use the rest of the
manual. Finally, at the end of this chapter you’ll find an explana-
tion of the differences between the DMS 2 and DMS 2E
instruments. You’ll need to refer to the rest of the manual for
detailed information on the specific features you’ll use most.
You’ll find the following sections in this chapter:
• Ten Steps to Launch Your Gauge (Section 1.2)
• How the DMS 2 Measures Thickness (Section 1.3)
• Important Features of the DMS 2 (Section 1.4)
• What’s in this Manual (Section 1.5)
1.2 Ten Steps to Launch Your Gauge
This quick-start procedure is designed to help you quickly use
the instrument. Most measurement applications and user
preferences will require that you take additional set-up steps
before you can measure and record “live” inspection data.
Even if additional adjustments are required, you’ll find it much
easier to make the adjustments and locate information in this
instruction manual after you work through this quick-start
procedure.
Follow these steps to launch your gauge.
Step 1: Install four (4) AA size alkaline batteries in the instru-
ment, as shown in Figure 1-1. (Refer to Section 3.1 for infor-
mation on using rechargeable batteries.)
1. Getting Started

1. Getting Started
Page 2 DMS 2 Operating Manual
Step 2: Select a compatible probe and plug its cable into the
top of the gauge as shown in Figure 1-2. Note that if you install
a single-element style probe, you won’t be able to select the
dual measurement mode as specified in Step 3. (Refer to
Chapter 7 for probe selection.)
Step 3: Press to turn on the DMS 2. The TG menu will
be displayed with the TGMODE submenu accessed. Use the
under each selection to choose the settings shown in
Figure 1-3. Note that if you’ve installed a DIALOG probe, the
instrument will automatically recognize it. (You may set the
instrument’s time and date, at this point, by following the steps
in Section 3.2.2. Refer to Sections 3.2 and 3.3 for complete
setupinstructions.)
FIGURE 1-1—Install four AA alkaline batteries in the instrument as shown here.

1. Getting Started
DMS 2 Operating Manual Page 3
Step 4: If you select the AUTO zeroing procedure, the instru-
ment will zero the probe on its own. If instead you selected
manual zeroing, zero the instrument-probe combination by
using the following procedure.
• With the probe uncoupled (not touching any material),
press .
• Couple the probe’s measurement surface (after applying
couplant) to the ZERO BLOCK on the front of the DMS 2.
• The instrument display will indicate when the zeroing
process is complete.
NOTE: Couplant must be used between the measurement
surfaces of all probes and the material being tested. Thickness
readings can not be obtained without the use of couplant.
Step 5: Determine the material velocity by performing a one-
point calibration. Note that while the default velocity setting
represents common steel (0.2313 × 106inches per second),
you must calibrate the instrument to match the specific
material that you’re inspecting. In Step 3, you selected the dual
measurement mode. Most probes will allow you to perform a
one-point calibration and operate in this mode. See Sections
3.3.1 and 3.3.4 for additional calibration options. Otherwise,
use the following procedure to calibrate your instrument.
FIGURE 1-2—The instrument’s connectors are shown here.

1. Getting Started
Page 4 DMS 2 Operating Manual
FIGURE 1-3—Shown here are the five selections contained in the TGMODE submenu. Follow the
instructions in this figure to continue the initial setup of your instrument.

1. Getting Started
DMS 2 Operating Manual Page 5
couplant and couple the attached probe to the material that
FIGURE 1-4—A calibration standard of known thickness is
required to properly calibrate the DMS 2. The standard
should be constructed of the same material that you’ll be
inspecting. This figure also shows how the display screen
will appear during the calibration process (A-scan has been
omitted for clarity).
• Select a test standard with a known thickness. The
standard should be made of the same material that you’ll
be testing, and ≥ the thickest measurement expected.
• Start the calibration process by pressing .
• Apply couplant to the calibration standard and couple the
probe to the known-thickness calibration standard.
• Follow the instructions displayed in Figure 1-4 and press
to change the displayed thickness reading until it
matches the standard’s known thickness.
• When the displayed and known thicknesses match, press
. This process will determine the velocity at which
sound moves through the material being tested.
The calibration procedure is now complete.

1. Getting Started
Page 6 DMS 2 Operating Manual
Step 6: Press to activate the Test Mode. Your DMS 2
display should look like the one shown in Figure 1-5. Apply
couplant to test sample you wish to test. It’s best to select a
test sample that’s free of paint and coating. If you’re testing
material that has a coating or paint, you must select a multi-
echo measurement mode (Return to
Step 3 and set the
mode to Dual-M, S-Peak or S-Flank. Alternatively, you can
inspect coated material using the optional TopCOAT mode.
Remember that the type of material being tested should
match the material used to make the calibration standard in
Step 5.

1. Getting Started
DMS 2 Operating Manual Page 7
FIGURE 1-5—With the probe
coupled (be sure to use
couplant) and the instrument
set to the Test mode, the
DMS 2 display should look like
the one shown here. If your
instrument isn’t registering a
thickness value, first try
adjusting the GAIN, so that the
A-scan ECHO crosses the
A-gate. Press under GAIN
to change the level of gain.
Increasing the gain increases
the amplitude of the displayed
signal and the height of the
echo. (Refer to Section 4.4.2
for more information on
adjusting the GAIN, or see
Section 4.4.5 on how to
change the A-gate height.)

1. Getting Started
Page 8 DMS 2 Operating Manual
Step 7: Thickness data can be stored in data files in the
onboard data recorder. Before data can be recorded, a file
must be created using the FILE CREATION FUNCTION. This
(shown in Figure 1-6) is accessed by pressing .
Follow this example to create a linear file type.
• Activate the FILE CREATION FUNCTION by pressing
. Four selections will appear across the bottom of the
displayscreen.
• Press below the selection titled TYPE until
FILE TYPE LINEAR is displayed at the top of the screen.
• Press below the selection titled ITEM. You’ll
note that these items define features of the data file. The
following ITEM must be specified during the file creation
process for a LINEAR file type (Example):
1. START POINT (first point in the file)
2. END POINT (last point)
• With the item START POINT highlighted, press below
the VALUE selection until the number 3 appears.
• Now, press below the ITEM selection until END POINT
ishighlighted.Then, press below the VALUE selection
until the number 10 appears.
• You’ve now specified a linear file type with eight data points
(numbered from 3 to 10). For now, we’ll leave READING
TYPE set to STANDARD.
• Now that all ITEMS have been specified, press
under the selection NEXT to continue the file
creation process. The virtual keyboard will open, giving you
the chance to specify the file name. After specifying the file
name, as described in Step 8, you’ll return to the FILE
CREATION SCREEN 2 shown in Figure 1-6. This screen
will allow you to add descriptive notes to the file and finish
the file creation process.

1. Getting Started
DMS 2 Operating Manual Page 9
FIGURE 1-6—Pressing
activates the FILE
CREATION FUNCTION. Here,
the user completes the first
step in the file creation
process by specifying the
file type. (In this case, the
LINEAR file type has been
selected.) The user then
defines various file features
called ITEMs. The second
display, which appears
during the file creation
process, allows the user to
specify the File Name (as
shown in Figure 1-7) and
maximum and minimum
acceptable material
thicknesses. In Section
5.3.2, you’ll learn how to use
this screen to insert various
descriptions into the file
header (specifying the probe
serial number, for instance).