Waygate Technologies USM Go+ Operating Manual

USM Go
USM Go+

Technical Reference and Operating Manual Id. No. 49 155

This issue 6 (02/2013) applies to the following software versions:

USM Go: 2.08 (March 6, 2013)

USM Go+: 2.08 (May 28, 2013)

You will find the software version and the serial number of your instrument on the second operating level
(CONFIG2 - ABOUT)

© GE Sensing & Inspection Technologies GmbH | Technical content subject to change without notice.

First operating level (Base)

To change between the first and the second operating level:

USM Go: Press the joystick for 2 seconds.

USM Go+: Press the center key of the keypad for 2 seconds.

USM Go Issue 6 (02/2013) 0-3

First operating level (Options)

To change between the first and the second operating level:

USM Go: Press the joystick for 2 seconds.

USM Go+: Press the center key of the keypad for 2 seconds.

0-4 Issue 6 (02/2013) USM Go

Second operating level

USM Go Issue 6 (02/2013) 0-5

Second operating level (continued)

0-6 Issue 6 (02/2013) USM Go

Status display icons

Icon Meaning Icon Meaning

SD memory card is inserted,
flashes when the SD card is accessed

Angle-beam probe 30° … 90°, flat surface,
Reflection from the backwall

Freeze active (Freeze),
Display is „frozen“.

Angle-beam probe 30°, curved surface,
Reflection from the inner surface of tube

Magnify gate is active Angle-beam probe 80°, curved surface,

Reflection from the outer surface of tube

Pulser-receiver separation is turned off Angle-beam probe 90°, surface wave

Pulser-receiver separation is turned on DAC mode = TCG is active

Pulser-receiver separation is turned on and set

DGS reference echo has been recorded

to through-transmission mode

Reject function is active DGS reference echo has been recorded,

transfer loss > 0

AGT is active dB REF is active

Calibration reminder

USM Go Issue 6 (02/2013) 0-7

Power level indicators Keypad functions

3

4

2

2

3

4

5

5

USM Go USM Go+

Icon Meaning

Battery charge level,
remaining operating time
in hours (approximate value)

Charger/power adapter is connected,
percentage of battery charge level
(approximate value)

Warning: Low battery charge level,
remaining operating time
in minutes (approximate value)

1

1

1 Increasing the gain level in increments

2 Decreasing the gain level in increments

3 Navigation operating levels and function groups

4 Function key 1, individually assignable

5 Function key 2, individually assignable

0-8 Issue 6 (02/2013) USM Go

Navigation using joystick (USM Go) or keypad (USM Go+)

USM Go USM Go+ Function

Navigation between function groups,
adjusting values

Navigation within a function group,
adjusting values

Changing between operating levels (press for 2 seconds)

USM Go Issue 6 (02/2013) 0-9

0-10 Issue 6 (02/2013) USM Go

Contents

0 Übersichten

First operating level (Base). . . . . . . . . . . . 0-3

First operating level (Options). . . . . . . . . . 0-4

Second operating level . . . . . . . . . . . . . . . 0-5

Second operating level (continued) . . . . . 0-6

Status display icons . . . . . . . . . . . . . . . . . 0-7

Power level indicators. . . . . . . . . . . . . . . . 0-8

Keypad functions . . . . . . . . . . . . . . . . . . . 0-8

Navigation using joystick (USM Go)

or keypad (USM Go+). . . . . . . . . . . . . . . . 0-9

1 Introduction

1.1 Safety information . . . . . . . . . . . . . . . . . 1-2

Battery operation . . . . . . . . . . . . . . . . . . . 1-2

Software . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Defects/errors and exceptional stresses. . 1-3

1.2 Important information on

ultrasonic testing . . . . . . . . . . . . . . . . . . 1-3

Prerequisites for testing with

ultrasonic test equipment . . . . . . . . . . . . . 1-3

Operator training . . . . . . . . . . . . . . . . . . . . 1-4

Technical test requirements . . . . . . . . . . . 1-4

Limits of testing . . . . . . . . . . . . . . . . . . . . . 1-5

Ultrasonic wall thickness measurement . . 1-5

Effect of the test object material . . . . . . . . 1-5

Effect of temperature variations . . . . . . . . 1-6

Measurement of remaining wall thickness 1-6

Ultrasonic evaluation of flaws . . . . . . . . . . 1-6

Flaw boundary method . . . . . . . . . . . . . . . 1-6

Echo display comparison method . . . . . . . 1-7

1.3 The USM Go. . . . . . . . . . . . . . . . . . . . . . . 1-8

Instrument versions USM Go and USM Go+1-9

Options . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

Special features of the USM Go . . . . . . . 1-11

1.4 The DMS Go. . . . . . . . . . . . . . . . . . . . . . 1-12

1.5 How to use this manual . . . . . . . . . . . . 1-12

USM Go Issue 6 (02/2013) 0-1

Contents

1.6 Layout and presentation in

this manual . . . . . . . . . . . . . . . . . . . . . . 1-13

Attention and note symbols. . . . . . . . . . . 1-13

Listings . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13

Operating steps. . . . . . . . . . . . . . . . . . . . 1-13

2 Standard package and accessories

2.1 Standard package . . . . . . . . . . . . . . . . . . 2-2

2.2 Add-on functions . . . . . . . . . . . . . . . . . . 2-3

2.3 Preconfigured function packages. . . . . 2-4

2.4 Recommended accessories. . . . . . . . . . 2-5

3 Initial start-up

3.1 Instrument positioning . . . . . . . . . . . . . . 3-2

3.2 Power supply. . . . . . . . . . . . . . . . . . . . . . 3-2

Operation with charger/power adapter . . . 3-2

Operation using batteries . . . . . . . . . . . . . 3-4

Charging the batteries. . . . . . . . . . . . . . . . 3-8

3.3 Connecting a probe . . . . . . . . . . . . . . . . 3-9

3.4 Inserting the SD memory card. . . . . . . 3-10

3.5 Starting the USM Go . . . . . . . . . . . . . . . 3-11

Powering On . . . . . . . . . . . . . . . . . . . . . . 3-11

Powering Off . . . . . . . . . . . . . . . . . . . . . . 3-12

Factory default setting (Reset) . . . . . . . . 3-12

4 Principles of operation

4.1 Overview of operator's controls . . . . . . 4-2

4.2 Display screen. . . . . . . . . . . . . . . . . . . . . 4-3

A-scan representation . . . . . . . . . . . . . . . . 4-3

Functions on the display screen . . . . . . . . 4-4

Gain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

Measurement line . . . . . . . . . . . . . . . . . . . 4-5

Status display icons . . . . . . . . . . . . . . . . . 4-6

Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

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Contents

4.3 Navigation and function keys . . . . . . . . 4-7

Navigation. . . . . . . . . . . . . . . . . . . . . . . . . 4-7

Function keys . . . . . . . . . . . . . . . . . . . . . . 4-7

Key combinations . . . . . . . . . . . . . . . . . . . 4-8

Power key . . . . . . . . . . . . . . . . . . . . . . . . . 4-8

4.4 Operational concept . . . . . . . . . . . . . . . . 4-9

Operating levels . . . . . . . . . . . . . . . . . . . . 4-9

Selecting and setting functions . . . . . . . . . 4-9

Function HOME . . . . . . . . . . . . . . . . . . . 4-11

Activating functions. . . . . . . . . . . . . . . . . 4-12

4.5 Important default settings . . . . . . . . . . 4-13

Language setting . . . . . . . . . . . . . . . . . . 4-13

Units setting . . . . . . . . . . . . . . . . . . . . . . 4-14

Decimal separator. . . . . . . . . . . . . . . . . . 4-14

Date format, Date, and Time . . . . . . . . . 4-15

Selecting the instrument orientation . . . . 4-16

4.6 Default settings of the display. . . . . . . 4-16

Selecting the color scheme. . . . . . . . . . . 4-16

Selecting the A-scan color . . . . . . . . . . . 4-17

Selecting the grid . . . . . . . . . . . . . . . . . . 4-18

Setting the brightness . . . . . . . . . . . . . . . 4-18

4.7 Saving the settings. . . . . . . . . . . . . . . . 4-19

Recalling settings . . . . . . . . . . . . . . . . . . 4-21

Displaying dataset name. . . . . . . . . . . . . 4-22

5 Operation

5.1 Overview of the functions . . . . . . . . . . . 5-2

Function groups first operating level . . . . . 5-3

Function groups second operating level . . 5-4

5.2 Setting the gain. . . . . . . . . . . . . . . . . . . . 5-6

Setting the dB increment of gain. . . . . . . . 5-6

5.3 Assignment of function keys. . . . . . . . . 5-8

5.4 Setting the display range

(function group RANGE) . . . . . . . . . . . 5-10

RANGE . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11

PROBE DELAY. . . . . . . . . . . . . . . . . . . . 5-11

VELOCITY . . . . . . . . . . . . . . . . . . . . . . . 5-12

DISPLAY DELAY . . . . . . . . . . . . . . . . . . 5-13

USM Go Issue 6 (02/2013) 0-3

Contents

5.5 Setting the pulser

(function group PULSER). . . . . . . . . . . 5-14

VOLTAGE (pulser voltage) . . . . . . . . . . . 5-14

ENERGY. . . . . . . . . . . . . . . . . . . . . . . . . 5-15

WIDTH . . . . . . . . . . . . . . . . . . . . . . . . . . 5-16

DAMPING . . . . . . . . . . . . . . . . . . . . . . . . 5-17

PRF MODE (pulse repetition frequency) . .5-17

5.6 Setting the receiver

(function group RECEIVER). . . . . . . . . 5-19

FREQUENCY . . . . . . . . . . . . . . . . . . . . . 5-19

RECTIFY. . . . . . . . . . . . . . . . . . . . . . . . . 5-20

DUAL (pulser-receiver separation) . . . . . 5-20

REJECT . . . . . . . . . . . . . . . . . . . . . . . . . 5-21

5.7 Setting the gates
(function groups

GATE A and GATE B) . . . . . . . . . . . . . . 5-22

Tasks of the gates. . . . . . . . . . . . . . . . . . 5-22

A-START/B-START

(starting point of the gate) . . . . . . . . . . . . 5-23

A-WIDTH/B-WIDTH

(width of the gates) . . . . . . . . . . . . . . . . . 5-23

A-THRESHOLD/B-THRESHOLD
(response and measurement

threshold of the gate) . . . . . . . . . . . . . . . 5-24

TOF MODE . . . . . . . . . . . . . . . . . . . . . . . 5-25

Starting point of gate B . . . . . . . . . . . . . . 5-27

Automatic gate height . . . . . . . . . . . . . . . 5-28

5.8 Calibrating the USM Go . . . . . . . . . . . . 5-29

Calibrating the display range. . . . . . . . . . 5-29

Choice of the measuring point . . . . . . . . 5-29

Calibration with straight-beam and

angle-beam probes . . . . . . . . . . . . . . . . . 5-30

Calibration using dual-element probes . . 5-34

5.9 Making measurements . . . . . . . . . . . . . 5-37

General notes . . . . . . . . . . . . . . . . . . . . . 5-37

5.10 dB-difference measurement

(function group dB REF) . . . . . . . . . . . 5-38

Recording a reference echo . . . . . . . . . . 5-39

Deleting a reference echo . . . . . . . . . . . . 5-39

Echo height comparison . . . . . . . . . . . . . 5-40

0-4 Issue 6 (02/2013) USM Go

Contents

5.11 Rating of welds

(function group AWS D1.1) . . . . . . . . . 5-41

Rating of welds according to AWS D1.1. 5-42

5.12 Flaw position calculation with

angle-beam probes. . . . . . . . . . . . . . . . 5-45

PROBE ANGLE . . . . . . . . . . . . . . . . . . . 5-46

THICKNESS . . . . . . . . . . . . . . . . . . . . . . 5-47

X VALUE. . . . . . . . . . . . . . . . . . . . . . . . . 5-48

O-DIAMETER . . . . . . . . . . . . . . . . . . . . . 5-48

COLOR LEG. . . . . . . . . . . . . . . . . . . . . . 5-49

5.13 Defining the probe angle . . . . . . . . . . . 5-50

BLOCK . . . . . . . . . . . . . . . . . . . . . . . . . . 5-51

5.14 Enabling options (Upgrade). . . . . . . . . 5-52

5.15 Configuring the USM Go for

test tasks . . . . . . . . . . . . . . . . . . . . . . . . 5-53

TOF MODE. . . . . . . . . . . . . . . . . . . . . . . 5-53

Phantom echo detector. . . . . . . . . . . . . . 5-58

Configuring the measurement line . . . . . 5-59

Enlarged display of reading . . . . . . . . . . 5-62

LARGE (alarm signal). . . . . . . . . . . . . . . 5-64

MAGNIFY GATE (spanning the gate). . . 5-65

Activating the magnify gate function . . . . 5-66

Automatic A-scan freeze (Freeze) . . . . . 5-68

5.16 Setting the display . . . . . . . . . . . . . . . . 5-70

ASCAN FILL . . . . . . . . . . . . . . . . . . . . . . 5-71

Working with Echo Max . . . . . . . . . . . . . 5-72

5.17 General setup . . . . . . . . . . . . . . . . . . . . 5-73

EVAL MODE . . . . . . . . . . . . . . . . . . . . . . 5-73

Gate logic . . . . . . . . . . . . . . . . . . . . . . . . 5-74

Selecting the pulser type. . . . . . . . . . . . . 5-75

Locking the joystick. . . . . . . . . . . . . . . . . 5-76

Configuring the alarm output. . . . . . . . . . 5-77

Power saving mode . . . . . . . . . . . . . . . . 5-79

TOF in LAYER . . . . . . . . . . . . . . . . . . . . 5-80

Backwall echo attenuation (BEA) . . . . . . 5-82

Displaying the envelope curve

(ENVELOPE) . . . . . . . . . . . . . . . . . . . . . 5-83

Automatic gain control

(Auto Gain Control) . . . . . . . . . . . . . . . . . 5-84

USM Go Issue 6 (02/2013) 0-5

Contents

Calibration reminder . . . . . . . . . . . . . . . . 5-86

Password protection . . . . . . . . . . . . . . . . 5-87

5.18 Distance-amplitude correction (DAC) . 5-91

Recording a DAC curve . . . . . . . . . . . . . 5-92

Setting up the DAC . . . . . . . . . . . . . . . . . 5-94

Turning the DAC evaluation off. . . . . . . . 5-95

Deleting the DAC curve . . . . . . . . . . . . . 5-96

Editing DAC points . . . . . . . . . . . . . . . . . 5-96

Adding DAC points . . . . . . . . . . . . . . . . . 5-97

Multiple DAC curves . . . . . . . . . . . . . . . . 5-97

AWS D1.1 in DAC/TCG . . . . . . . . . . . . . 5-99

Sensitivity correction . . . . . . . . . . . . . . . . 5-99

Echo evaluation using DAC/TCG . . . . . 5-100

5.19 Distance-amplitude curve according to

JIS Z3060-2002 (JISDAC) . . . . . . . . . . 5-102

Activating JISDAC

(DAC according to JIS) . . . . . . . . . . . . 5-102

Recording a DAC curve . . . . . . . . . . . . 5-102

Setting up JISDAC . . . . . . . . . . . . . . . . 5-105

Sensitivity correction . . . . . . . . . . . . . . . 5-106

Turning the JISDAC evaluation off . . . . 5-106

Deleting the DAC curve. . . . . . . . . . . . . 5-107

Echo evaluation using DAC . . . . . . . . . 5-107

5.20 Distance-amplitude curve
according to JB/T4730 and

GB 11345 (CNDAC) . . . . . . . . . . . . . . . 5-109

Evaluations according to CNDAC . . . . . 5-109

Standards and reference blocks . . . . . . 5-110

Activating the CNDAC. . . . . . . . . . . . . . 5-111

Recording a DAC curve . . . . . . . . . . . . 5-111

Setting up CNDAC . . . . . . . . . . . . . . . . 5-114

Sensitivity correction . . . . . . . . . . . . . . . 5-115

Adjusting reference lines. . . . . . . . . . . . 5-116

Turning the CNDAC evaluation off . . . . 5-116

Deleting the DAC curve. . . . . . . . . . . . . 5-117

Echo evaluation using DAC . . . . . . . . . 5-117

5.21 Evaluation according to the

DGS method . . . . . . . . . . . . . . . . . . . . 5-119

Using the DGS for measurements . . . . 5-119

Validity of the DGS method. . . . . . . . . . 5-121

0-6 Issue 6 (02/2013) USM Go

Contents

Starting the echo height evaluation

according to DGS . . . . . . . . . . . . . . . . . 5-123

Basic settings for the

DGS measurement . . . . . . . . . . . . . . . . 5-123

Recording a reference echo and

turning the DGS curve on . . . . . . . . . . . 5-125

Locks, error messages . . . . . . . . . . . . . 5-127

Sound attenuation and

transfer correction. . . . . . . . . . . . . . . . . 5-128

Using multiple DGS curves. . . . . . . . . . 5-128

Turning the DGS evaluation off . . . . . . 5-129

Deleting a DGS reference echo . . . . . . 5-129

Probe data . . . . . . . . . . . . . . . . . . . . . . 5-130

trueDGS angle-beam probes . . . . . . . . 5-133

6 Documentation

6.1 Test reports. . . . . . . . . . . . . . . . . . . . . . . 6-2

Storing test reports . . . . . . . . . . . . . . . . . . 6-2

Displaying test reports . . . . . . . . . . . . . . . 6-4

Printing test reports. . . . . . . . . . . . . . . . . . 6-6

Deleting test reports . . . . . . . . . . . . . . . . . 6-7

Storing the A-scan and parameters

in the test report . . . . . . . . . . . . . . . . . . . . 6-9

6.2 Storing memos . . . . . . . . . . . . . . . . . . . 6-10

Creating a new memo file . . . . . . . . . . . . 6-10

Editing a memo file . . . . . . . . . . . . . . . . . 6-11

Attaching a memo file to test report . . . . 6-12

6.3 Storing a report header . . . . . . . . . . . . 6-13

Creating a new header file . . . . . . . . . . . 6-13

Editing a header file . . . . . . . . . . . . . . . . 6-14

Including a header file in the test report . 6-15

6.4 Viewing and storing parameters . . . . . 6-16

6.5 Videos . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17

Recording a video . . . . . . . . . . . . . . . . . . 6-17

Viewing a video. . . . . . . . . . . . . . . . . . . . 6-19

6.6 Documentation using UltraMATE . . . . 6-21

6.7 Data Recorder (option). . . . . . . . . . . . . 6-22

Creating a Data Recorder file . . . . . . . . . 6-23

Activating a Data Recorder file . . . . . . . . 6-25

Storing readings in the grid matrix . . . . . 6-26

USM Go Issue 6 (02/2013) 0-7

Deleting readings . . . . . . . . . . . . . . . . . . 6-27

A-scan preview . . . . . . . . . . . . . . . . . . . . 6-28

Viewing Data Recorder files . . . . . . . . . . 6-28

Turning the grid matrix on/off . . . . . . . . . 6-29

Service interface (Mini RS232-C) . . . . . . . 8-3

8.2 Peripherals. . . . . . . . . . . . . . . . . . . . . . . . 8-4

9 Appendix

7 Maintenance and care

7.1 Instrument care. . . . . . . . . . . . . . . . . . . . 7-2

7.2 Battery care . . . . . . . . . . . . . . . . . . . . . . . 7-2

Battery care. . . . . . . . . . . . . . . . . . . . . . . . 7-2

Charging the batteries. . . . . . . . . . . . . . . . 7-3

7.3 Maintenance . . . . . . . . . . . . . . . . . . . . . . 7-3

7.4 Software updates . . . . . . . . . . . . . . . . . . 7-4

Download of update files. . . . . . . . . . . . . . 7-4

Installing an update. . . . . . . . . . . . . . . . . . 7-5

8 Interfaces and Peripherals

8.1 Interfaces. . . . . . . . . . . . . . . . . . . . . . . . . 8-2

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2

USB interface . . . . . . . . . . . . . . . . . . . . . . 8-3

0-8 Issue 6 (02/2013) USM Go

9.1 Function directory. . . . . . . . . . . . . . . . . . 9-2

9.2 EU Declaration of Conformity . . . . . . . 9-11

9.3 Manufacturer/Service addresses. . . . . 9-11

9.4 Environmental protection regulations 9-13

WEEE directive (Waste Electrical and

Electronic Equipment) . . . . . . . . . . . . . . . 9-13

Disposal of batteries . . . . . . . . . . . . . . . . 9-14

9.5 Recycling directives . . . . . . . . . . . . . . . 9-16

Overview . . . . . . . . . . . . . . . . . . . . . . . . . 9-16

Materials to be disposed of separately . . 9-19

Other materials and components . . . . . . 9-22

Recycling data of the USM Go . . . . . . . . 9-29

10 Specifications

10.1 Specifications of

USM Go and USM Go+ . . . . . . . . . . . . . 10-2

Display screen . . . . . . . . . . . . . . . . . . . . 10-2

Display . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3

Connectors . . . . . . . . . . . . . . . . . . . . . . . 10-3

Memory. . . . . . . . . . . . . . . . . . . . . . . . . . 10-4

Pulser . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4

Receiver . . . . . . . . . . . . . . . . . . . . . . . . . 10-5

Gates . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6

Memory. . . . . . . . . . . . . . . . . . . . . . . . . . 10-6

Environment . . . . . . . . . . . . . . . . . . . . . . 10-7

Protection . . . . . . . . . . . . . . . . . . . . . . . . 10-8

Options . . . . . . . . . . . . . . . . . . . . . . . . . . 10-9

10.2 Specifications according to

EN 12668 . . . . . . . . . . . . . . . . . . . . . . . 10-11

Contents

11 Index

USM Go Issue 6 (02/2013) 0-9

0-10 Issue 6 (02/2013) USM Go

Introduction 1

USM Go Issue 6 (02/2013) 1-1

1 Introduction Safety information

ATTENTION

1.1 Safety information

The USM Go has been designed and tested according
to DIN

EN 61010-1: 2011-07, Safety requirements for
electrical equipment for measurement, control and lab
oratory use, and was technically in perfectly safe and
faultless condition when leaving the manufacturing
works.

In order to maintain this condition and to ensure a safe
operation, you should always read the following safety
information carefully before putting the instrument into
operation.

The USM Go is an instrument for materi­als testing. Any use for medical or any
other applications is not permitted!

The instrument may only be used in industri­al environments.

The USM Go is waterproof according to IP67. It can be
operated either with the corresponding lithium-ion bat
teries or with the charger/power adapter. The charger/
power adapter meets the requirements of electrical
safety class II.

-

Battery operation

For the battery operation of the USM Go, we recom­mend the corresponding lithium-ion battery. You should
only use this battery for the battery operation.

­You can charge the lithium-ion battery either within the
instrument itself or in an external charger. If a lithium-ion
battery is inserted, charging starts automatically as
soon as you connect the charger/power adapter to the
USM Go and to the mains power supply.

For power supply, please also see Chapter 3.2 Power
supply, page 3-2. For the use of batteries, please also
see Chapter 7.2 Battery care, page 7-2.

Software

According to the current state of the art, software is nev­er completely free from errors. Before using any soft­ware-controlled test equipment, it is therefore neces­sary to make sure that the required functions operate
perfectly in the intended combination.

If you have any questions about the use of your test
equipment, please contact your nearest representative
of GE Sensing & Inspection Technologies.

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Important information on ultrasonic testing 1 Introduction

Defects/errors and exceptional stresses

If you have reason to believe that a safe operation of
your USM Go is no longer possible, you have to discon
nect the instrument and secure it against unintentional
re-connection. Remove the lithium-ion battery.

A safe operation is no longer possible for example

● if the instrument shows visible damages,

● if the instrument no longer operates perfectly,

● after prolonged storage under adverse conditions

(e.g. exceptional temperatures or especially high air
humidity, or corrosive environmental conditions),

● after being subjected to heavy stresses during trans­portation.

1.2 Important information on ultrasonic testing

­Please read the following information before using your

USM Go. It is important that you understand and ob
serve this information to avoid any operator errors that
might lead to false test results. Such false test results
could result in personal injuries or property damages.

Prerequisites for testing with ultrasonic test equipment

This operating manual contains essential information on
how to operate your test equipment. In addition, there
are a number of factors that affect the test results, but a
description of all these factors goes beyond the scope
of this operating manual. The three most important pre
requisites for a safe and reliable ultrasonic inspection
are:

● Operator training

● Knowledge of special technical test requirements and

limits

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● Choice of appropriate test equipment

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1 Introduction Important information on ultrasonic testing

Operator training

The operation of an ultrasonic test device requires prop­er training in ultrasonic test methods.

Proper training comprises for example adequate knowl­edge of:

● the theory of sound propagation,

● the effects of sound velocity in the test material,

● the behavior of the sound wave at interfaces between

different materials,

● the propagation of the sound beam,

● the influence of sound attenuation in the test object

and the influence of surface quality of the test object.

Lack of such knowledge could lead to false test results
with unforeseeable consequences. You can contact for
example NDT societies or organizations in your country
(DGZfP in Germany; ASNT in the USA), or also GE
Sensing & Inspection Technologies, for information on
the existing opportunities for training of ultrasonic in
spectors as well as on the qualifications and certificates
that can finally be obtained.

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Technical test requirements

Every ultrasonic test is subject to specific technical test
requirements. The most important ones are:

● the definition of the scope of inspection

● the choice of the appropriate test method

● the consideration of material properties

● the determination of limits for recording and evalua-

tion.

It is the task of the those with overall responsibility for
testing to ensure that the inspector is fully informed
about these requirements. The best basis for such infor
mation is experience with identical test objects. It is also
essential that the relevant test specifications be clearly
and completely understood by the inspector.

GE Sensing & Inspection Technologies regularly holds
specialized training courses in the field of ultrasonic
testing. The scheduled dates for these courses will be
given to you on request.

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Important information on ultrasonic testing 1 Introduction

Limits of testing

The information obtained from ultrasonic tests only re­fers to those parts of the test object which are covered
by the sound beam of the probe used.

Any conclusions from the tested parts to be applied to
the untested parts of the test object should be made with
extreme caution.

Such conclusions are generally only possible in cases
where extensive experience and proven methods of sta
tistical data acquisition are available.

The sound beam can be completely reflected from
boundary surfaces within the test object so that flaws
and reflection points lying deeper remain undetected. It
is therefore important to make sure that all areas to be
tested in the test object are covered by the sound beam.

Ultrasonic wall thickness measurement

All ultrasonic wall thickness measurements are based
on a time-of-flight measurement. Accurate measure
ment results require a constant sound velocity in the test
object. In test objects made of steel, even with varying
alloying constituents, this condition is mostly fulfilled.
The variation of sound velocity is so slight that it is only

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of importance for high-precision measurements. In oth
er materials, e.g. nonferrous metals or plastics, the
sound velocity variations may be even larger and thus
affect the measuring accuracy.

Effect of the test object material

If the material of the test object is not homogeneous, the
sound waves may propagate at different velocities in dif
ferent parts of the test object. An average sound velocity

­should then be taken into account for the range calibra

tion. This is achieved by using a reference block with a
sound velocity equal to the average sound velocity of
the test object.

If substantial sound velocity variations are expected,
then the instrument calibration should be adjusted to the
actual sound velocity values at shorter time intervals.
Failure to do so may lead to false thickness readings.

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1 Introduction Important information on ultrasonic testing

Effect of temperature variations

The sound velocity within the test object also varies as
a function of the material's temperature. This can cause
appreciable errors in measurements if the instrument
has been calibrated on a cold reference block, whereas
the measurement is carried out on a warm test object.
Such measurement errors can be avoided either by ad
justing the temperature of the reference block used for
calibration or by taking the temperature effect into con
sideration on the basis of a correction factor obtained
from published tables.

Measurement of remaining wall thickness

The measurement of the remaining wall thickness on
plant components, e.g. pipes, tanks, and reaction ves
sels of all types which are corroded or eroded from the
inside, requires a perfectly suitable gauge and special
care in handling the probe.

The inspectors should always be informed about the
corresponding nominal wall thicknesses and the likely
amount of wall thickness losses.

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Ultrasonic evaluation of flaws

In present-day test practice, there are basically two dif­ferent methods of flaw evaluation:

If the diameter of the sound beam is smaller than the ex­tent of the flaw, then the sound beam can be used to ex­plore the boundaries of the flaw and thus determine its

­area.

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If, however, the diameter of the sound beam is larger
that the extent of the flaw, the maximum echo indication
from the flaw must be compared with the maximum
echo indication from an artificial flaw provided for com
parison purposes.

Flaw boundary method

The smaller the diameter of the probe's sound beam,
the more accurately the boundaries, i.e. the actual flaw
area, can be determined by the flaw boundary method.
If, however, the sound beam is relatively broad, the flaw
area determined can substantially differ from the actual
flaw area. Care should therefore be taken to select a
probe which will give a sufficiently narrow sound beam
at the position of the flaw.

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Important information on ultrasonic testing 1 Introduction

Echo display comparison method

The echo from a small, natural flaw is usually smaller
than the echo from an artificial comparison flaw, e.g. cir
cular disc flaw of the same size. This is due, for in­stance, to the roughness of the surface of a natural flaw,
or to the fact that the sound beam does not impinge on
it at right angles.

If this fact is not taken into account when evaluating nat­ural flaws, there is a risk of false evaluation.

In the case of very jagged or fissured flaws, e.g. shrink
holes in castings, it may be that the sound scattering oc
curring at the boundary surface of the flaw is so strong
that no echo at all is produced. In such cases, a different
evaluation method should be chosen, e.g. use of the
backwall echo attenuation in the evaluation.

The distance sensitivity of the flaw echo plays an impor­tant part when testing large components. Attention
should be paid here to choosing artificial comparison
flaws which are as far as possible governed by the same
"distance laws" as the natural flaws to be evaluated.

The ultrasonic wave is attenuated in any material. This
sound attenuation is very low, e.g. in parts made of fine­grained steel, likewise in many small parts made of oth

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er materials. However, if the sound wave travels larger
distances through the material, a high cumulative sound
attenuation can result, even with small attenuation coef
ficients. There is then a danger that echoes from natural
flaws appear too small. For this reason, an estimate
must always be made of the effects of attenuation on the
evaluation result and taken into account if applicable.

If the test object has a rough surface, part of the incident
sound energy will be scattered at its surface and is not

­available for the test. The larger this initial scattering, the

smaller the flaw echoes appear, and the more errors oc
cur in the evaluation result.

It is therefore important to take the effect of the test ob­ject's surfaces on the height of the echo into account
(transfer correction).

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1 Introduction The USM Go

1.3 The USM Go

The USM Go is a lightweight and compact ultrasonic
flaw detector which is especially suitable

● for locating and evaluating material flaws,

● for measuring wall thicknesses,

● for saving and documenting test results.

Due to its design, the USM Go can be used in almost all
flaw detection applications in a wide range of industries,
including aerospace, power generation, automotive, as
well as oil and gas. These include:

Weld inspection

● Trigonometric projections

● AWS

● DAC

● DGS

Inspection of forgings and castings

● Manual PRF adjustment

Rail inspection

● High PRF (up to 2000 Hz)

● Lightweight: 850 g (1.87 lb)

● Small and ergonomic

Inspection of composites

● RF display

● 2 gates A and B

● Gate B is triggered by the event in gate A

For even more demanding applications

● Narrow band-pass filters

● Low-noise digital amplifiers

● Optional square pulsers

● DAC (TCG) with 120 dB/µs slope

● Backwall echo attenuation (BEA)

● Phantom echo detector

● DGS

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The USM Go 1 Introduction

Instrument versions USM Go and USM Go+

A joystick is used in the USM Go for navigation, for
changing settings, and for selecting adjustment values.

USM Go

These functions are carried out by means of five keys in
the keypad of the USM

Go+. The arrow keys in the key-

pad correspond to the movement of the joystick in the
corresponding direction, and pressing the center key
corresponds to pressing the joystick.

USM Go+

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1 Introduction The USM Go

Options

Various options extend the basic functions of the USM
Go and can be enabled by a code in each case.

USM Go Base

● Basic version, for universal ultrasonic
test jobs.

USM Go AWS

● Amplitude evaluation according to AWS D1.1 for the
weld inspection.

USM Go DAC

● DAC amplitude evaluation using up to 16 points ac­cording to EN 1712, EN 1713, EN 1714, ASME, and
ASME

III, in conformity with JIS Z3060

● DAC (TCG) 110 dB dynamic

● DAC (BEA) 120 dB/µs slope

USM Go DGS

● DGS amplitude evaluation according to EN 1712

USM Go with an on-board data logger

● Recording and documentation of measurement val­ues in linear and grid file mode.

USM Go with square pulser

● Enables the fine adjustment of initial pulse parame­ters

● Voltage setting 120 … 300 V in increments of 10 V

● Pulse duration setting 30 … 500 ns in increments of

10

ns

● PRF

● 3G (gate C)

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