How to measure with the DGS, Introduction | Epson USN 52R, USN 52L

Introduction

How to measure with the DGS

1.1 How to measure with the DGS

The DGS option (Distance - Gain - Size) enables you to compare the reflecting power of a natural flaw in the test object with the reflecting power of a theoretical flaw (disk-shaped reflector) at the same depth.

AAttention:

You are comparing the reflecting power of a natural flaw with that of a theoretical flaw (= disk-shaped reflector) at the same depth. No definite conclusions with regard to the natural flaw (roughness, oblique

position, etc.) are permitted.

The basis of this comparison of the reflecting powers is the so-called DGS diagram. This diagram consists of a set of curves showing the interrelationship of three in- fluencing factors:

•Distance D between probe and disk-shaped reflector,

•Gain difference G between disk-shaped reflectors of different sizes and an infinitely large backwall,

•Size S of the disk-shaped reflector.

The factor S is always constant for one curve of the set of curves.

The following illustrates the general DGS diagram. This diagram is standardized with regard to the near-field length and the element diameter:

DGS-6

Issue 02, 03/99

Krautkramer USN 52R/USN 52L Option DGS

Image 181

Epson USN 52R, USN 52L manual How to measure with the DGS, Introduction

Contents

Technical Reference and Operating Manual USN 52R / USN 52L Index Introduction Function overview Basics of operation Recording a Distance-Amplitude Configuring the USN 52R/USN 52LStoring measured values Data Logger Printing display contents and instrument Printing instrument settingsDocumentation with the PC program Interfaces 10-7 10-210-8 Issue 05, 02/00 Krautkramer USN 52R/USN 52L Introduction Defects/errors and exceptional stresses Safety informationIntroduction Storage batteries Important notes Preconditions for testing with ultrasonic flaw detectorsSoftware Technical test requirements Operator training Wall thickness measurements with ultrasonics Limits of testingEffect of the material of the test object Effect of temperature variations Assessing flaws using ultrasonicsMeasurement of remaining wall thickness Flaw boundary scanning method Echo display comparison method USN 52R/USN 52L Special features of the two versionsUSN 52R USN 52L Introduction Service Getting to know the adjustment functionsSpecifications and basic settings Remarks on this manual Descriptions of functions Layout of this manualOperating steps Keys Issue 05, 02/00 Krautkramer USN 52R/USN 52L Standard package and accessories Standard package and accessories Product type Description Standard package Recommended accessories Required accessoriesProduct type Description Order no GCH1 Recommended outside products Issue 05, 02/00 Krautkramer USN 52R/USN 52L Setting into operation Setting into operation Power supplyPositioning the USN 52R/ USN 52L Inserting the batteries Setting into operation Battery operationAAttention Nickel Cadmium NiCd Left Alkaline Alk Right LED Using the battery chargerStatus Probe connection Starting the USN 52 R Switching on Screen saver Reset Basics of operation Basics of operation USN 52R and USN 52L USN 52L Scan display Display Functions on the display Measurement line Indications beneath the A-scanAngle and X-VALUE Status line Menu line Function keys KeypadSpecial keys Special keys of the USN 52L for setting the display Accelerated adjustment Setting the functionOperational concept Changing the operating levels Selection of measured value for enlarged display Function keys Only USN 52L Keys for special functions Setting the measurement units Important basic settingsSet language Operation Issue 05, 02/00 Krautkramer USN 52R/USN 52L Operation Operation Function overview first operating level Gain Gain adjustment Adjustment of the USN 52R/ USN 52LSetting the dB Step Range Calibration range Selection of basic dataCoarse in steps Delay Setting the delay MTL VEL Setting the sound velocity FREQ. Frequency Setting the receiver Damping Electrical damping of the probe RECTIF. Setting the rectification mode Pulser Changeover of initial pulse Setting the pulser REP-RATEset the required percentage value with M Start Gate adjustment Start Start of the gate Thresh Determination of thresholdWidth Width of the gate Start Gate start Calibration functions Adjustment of the freely selected value Zero Probe delayMTL VEL Sound velocity Data set names and Memo mode in .10 on Recall Loading of a stored settingStoring data Clearing the instrument setting Store Storing the instrument settingsSET# Selection of data set Displaying stored A-Scans preview Clearing all data Calibration of display range USN 52R/USN 52L calibration Calibration with a straight-beam probe Straight-beam probe with delay Known sound velocity Calibration with angle-beam probesUnknown sound velocity Path error Flank modeCalibration with a dual T/R probe Higher sound velocity Automatic calibration Preconditions Preparing the instrument for digital measurementGate Logic Recall of dB difference Set Amplitude to dB Threshold Calibrating the sensitivity B DAC/TCG Function group TCG DAC/TCG mode Operation Recording a Distance- Amplitude Curve Operation Operation DAMPING, FREQ.,RECTIF., MTL VEL, Pulser and Reject Echo evaluation withAmplitude is set to dB Threshold DAC mode TCG mode Preparations Measuring thicknessMeasuring the thickness Determining the number of Files Storing measured values Data LoggerNumber of measurement locations = 2500 Number of Files Selecting a File Clearing Files File Mode Thickness Copy Mode Datalogger MeasureStoring measured values File Number Viewing stored readings ErrorClearing the measured values Configuring the USN 52R/ USN 52L Left function group Left Table Value Diam Center Table MEAS.UNITS Right Table Amplitude Amplitude display Graticule Display graticule Intensity Display brightness only USN 52R Freeze Mode Storage modeHigh LOW DB Step Sets step range Gate Logic Setting the gate logic Location Selecting the measurement location File Number Selecting a file Value Displaying the measured value File Mode Enabling the Data LoggerClearing the measured value MEAS. Units Setting the measurement units Language Setting the display language Data set names Data set namesMemo function Data SET Name Entry of a data set name Data SET Direc Data set directory Memo Storing additional information Entering texts Filling in a data header Data set names Issue 05, 02/00 Krautkramer USN 52R/USN 52L Baud Rate Setting the transfer speed Setting the RS232 interfaceLength Setting the length of a byte Parity Parity check Printer type Copy Mode Setting data communicationHard Copy Mode Setting the flaw location calculation Thickness Material thickness Angle Angle of incidenceValue X-value of the probe Displaying the measured values Diam Test object diameter Measure Method of measurement for sound path measurement Setting the measurement methods TOF Measurement mode for time of flight Function check Locking set valuesAuxiliary devices Power supply Range Suppression Reject Damping Rectification Gate threshold Thickness measurement Issue 05, 02/00 Krautkramer USN 52R/USN 52L Documentation Printing instrument settings and display contents Copy Mode Documentation Documentation with the PC program UltraDOC Issue 05, 02/00 Krautkramer USN 52R/USN 52L Servicing and maintenance Maintenance of NiCd cells Cleaning the USN 52R/ USN 52LServicing and maintenance Charging NiCd cells Handling AlMn batteries Handling NiCd cells Issue 05, 02/00 Krautkramer USN 52R/USN 52L Interfaces, Peripherals Interfaces, Peripherals InterfacesSerial interface RS Interfaces, Peripherals Layout of 7 pin Lemo socket RS Layout of 4 pin Lemo socket charger socket, switching output Baud Rate Connection of a peripheral Printing Data Logger report Transferring the display contents Data Logger report format Operation Set Copy Mode to Report Interfaces, Peripherals Transferring measurements values in the Data Logger to a PC Transferring measurement values Transfer formats Printing display contents and instrument settings Byte-No Data Format X.XXX Esccodereturn USN 52R/USN 52L remote operation Interfaces, Peripherals Delay Length Store Sequence of commands of the Memo code Configuring the Memo functionDefining data header Number of fields Example for a header definition Eschn 9RETURN Entering Memo text Lemo Analog outputs Analog voltage for the sound path of an echo RF modeRectified echoes Measure = 0 to 1st TTL switching output Specifications Specifications Echo height resolution Measurement resolutionDisplay rectification Frequency -3dB ranges DAC/TCG Operating temperature Storage temperatureBattery mode Probe connectors Issue 05, 02/00 Krautkramer USN 52R/USN 52L Appendix Appendix Function directory DAC Echo TCG Curve TCGDAC/TCG TCG Damping Rcvr Data SET Preview MEM Data SET MEMFREQ. Rcvr Gain Pulser Puls MTL VEL BasicRecall MEM RECTIF. Rcvr REP-RATE Puls Reject PulsStore MEM Velocity #1 EC Certificate of Conformity Krautkrämer GmbH & Co. oHG Service addressesFrance Japan USA 10-10 Issue 05, 02/00 Krautkramer USN 52R/USN 52L Changes Changes Index Copy Mode DAC 12-4 Issue 05, 02/00 Krautkramer USN 52R/USN 52L Parameter Dump 5-58, 6-3 Parity Reject Krautkramer USN 52R/USN 52L Issue 05, 02/00 12-7 Value Zero 5-13 Zoom key Operating Manual Option DGS R5 TCG/DGS R6 TCG/DGS L4 TCG/DGS L5 TCG/DGS DGS-17 ContentsDGS-29 DGS-6 DGS-4 Issue 02, 03/99 Krautkramer USN 52R/USN 52L Option DGS DGS-5 How to measure with the DGS DGS-7 Overview of the method of proceeding Overview of the DGS menu Switch from TCG to DGS mode DGS modeOverview of the DGS menu Function group DGS mode Gain Menu functions Function table DGS mode PROBE-# ATT-REF Page Operating the DGS Operating the DGS Storing a new probe Operating the DGS Preparing the DGS evaluation Diameter of the equivalent Operating the DGS Carrying out a DGS evaluation Or O Switching off the DGS mode Switching off the DGS mode Storing data Page Codes for remote control Codes for remote control ATT-REF DGS-32 Issue 02, 03/99 Krautkramer USN 5 /USN 52L Option DGS