Principles of NDT Methods on Railway Axles

Transcription

1 Sheet 1 of 38 Dipl.-Ing. Thomas Heckel, BAM VIII.43 Dipl.Ing. Uwe Völz, BAM VIII.43 Dipl.-phys. Rainer Boehm, BAM VIII

2 Sheet 2 of Introduction 2. NDT by manufacturer 3. In-service inspection 4. In-service inspection 5. Signal processing

3 Sheet 3 of 38 High speeds High levels of dynamic stress Complex vehicle design More frequent testing Time-consuming removal of wheelsets Testing and diagnostics strategy based on mechanised testing facilities that enable the in situ and ex situ testing of wheelsets Introduction

4 Sheet 4 of Inspection of wheel rims 2 - Inspection of wheel discs Inspection after manufacturing 3 - Inspection of axle shafts 4 - Inspection of axles with longitudinal drilled hole 5 - Inspection of rails Automatic Testing on Railway Components

5 Sheet 5 of 38 Inspection after production In-service inspection Flaw Flaw Riss Amplitude F R R Amplitude F F2 soundpath Soundpath A-Scan A-Scan Soundpath Gate Amplitude Gate Ultrasonic Testing on Railway Axles

6 Sheet 6 of Introduction 2. NDT by manufacturer 3. In-service inspection 4. In-service inspection 5. Signal processing

7 Sheet 7 of 38 Inspection after production Goal: Flaw Find flaws caused by production process, Volumetric defects, non-metal inclusions, shrinking holes Testing technique: Amplitude F R R unfocused normal beam probe, Longitudinal wave, Frequency 2 MHz to 4 MHz, imersion technique Soundpath Acceptance criteria: A-Scan Amplitude height (DAC) Recording level DSR 2 mm or 3 mm Automated Inspection after Production

8 Sheet 8 of 38 Inspection has to be performed on complex geometries In the area close to the surface UT sensitivity is reduced (additional MT inspection) 2D-movement of probes is necessary to adapt to curved surface Inspection has to be finished in less than 15 minutes Question: Is there a way to improve UT inspection in production? Boundary conditions for UT inspection after production

9 Sheet 9 of 38 Probe used: Frequency = 10 MHz Focus = 100 mm Diameter = 10 mm Resolutionration of scan 0,1 mm by 0,1 mm Recording level DSR 0,125 mm High resolution measurements on axle (laboratory)

10 Sheet 10 of 38 v = v j v = v j + 12 db v = v j + 24 db *)Measrements performded on similar specimen Sizing of typical volumetric flaws can be performed down to DSR 0,2 mm, High resolution measurment for in-service inspection (laboratory)

11 Sheet 11 of Introduction 2. NDT by manufacturer 3. In-service inspection 4. In-service inspection 5. Signal processing

12 Sheet 12 of 38 Automated in-service inspection system for hollow axles

13 Sheet 13 of 38 In-service inpsection Flaw Crack Goal: Find defects caused by operation, find crack-type flaws Testing technique: Amplitude F F2 Unfocused angle beam probes, Typical angles of incidence: 38, 45, 70 Frequency 4 MHz or 5 MHz A-Scan A-Bild Soundpath gate Amplitude gate Soundpath Schallweg Acceptance criteria: Gate mode for amplitude and soundpath, recording level SCD 2mm In-service inspection of hollow axle

14 Sheet 14 of 38 R35 Center Inner surface R85 R90 α = 45 Outer surface Geometries and soundfields at three-center curves

15 Sheet 15 of 38 Inner surface Outer surface Rotation Rotation Soundpath Soundpath Saw cut on the shaft Saw cut on curve Typical indications of geometry change

16 Sheet 16 of 38 Using only information of the gate signal may reduce information (indication of flaw will be lost)! Example: Indications from geometry and flaw

17 Sheet 17 of 38 L P = 256 mm s = 77 mm s = 77 mm Typical indication from geometry using A-Scan method Inspection result: Geometry change at end of shaft

18 Sheet 18 of 38 s s Mounted seat unmounted seat u S = 78 mm u S = 81 mm Noise caused by the mounted wheel Noise removed using gate level 80% Comparison: Mounted and unmounted seat

19 Sheet 19 of 38 L P = 266 mm S = 85 mm! S = 85 mm! s = 77 mm s = 77 mm Soundpath of indications is too large there is no flaw Inspection result: Indication at posit ion= 266 mm

20 Sheet 20 of Introduction 2. NDT by manufacturer 3. In-service inspection 4. In-service inspection 5. Signal processing

21 Sheet 21 of 38 Inspection System Wittenberge Depot

22 Sheet 22 of 38 Phased Array Probe f = 2,7 MHz β = 48 Transducer Size: 22 x 20 mm 2 Number of Elements: 14 Angle of Incidence: 28 to 72 Priciple of Axle Testing with Phased Array Probes

23 Sheet 23 of 38 Delay Time Distribution Delay Time Distribution Position of Active Elements N N N Angle Focus Scan Electronic Change of Angle of Incidence Electronic Change of Point of Focus Electronic Change of Position of Soundbeam Possibilities of Phased Array Inspection Systems

24 Sheet 24 of 38 COMpact Phased Array Systems developed by BAM

25 Sheet 25 of 38 Development and Simulation of Probes

26 Sheet 26 of 38 Simulation Results for Soundfields

27 Sheet 27 of 38 Area of Interest Couplant (Water or Oil) Axle Phased Array Probe Wheel Disc Prototype of Phased Array Probe

28 Sheet 28 of 38 PK Displaying Measured Data

29 Sheet 29 of 38 O α = a 4a 4a 1a 1a a 5a 5a 3a 3a 2a 2a B 8a 5a 3a 2a 485 9a C A 6a mm 440 Results of Testing the Prepared Wheelset

30 Sheet 30 of 38 Areas of interest Wheelset with three brake discs Concept for Test-System

31 Sheet 31 of 38 PK 1 PK 3 PK 5 PK 6 PK 4 PK 2 Testing with six phased array probes Positioning of Phased Array Probes

32 Sheet 32 of 38 Example inspection data from a test shaft with reference defects

33 Sheet 33 of Introduction 2. NDT by manufacturer 3. In-service inspection 4. In-service inspection 5. Signal processing

34 Sheet 34 of 38 B2S B Scan Signal processing Wheeldisk Ø = 1400 mm RF data record Size of picture 1300 by 1300 mm 2 Signal processing for disks and axles using RF data 1/2

35 Sheet 35 of 38 B Scan Signal processing Signal processing for disks and axles using RF data 2/2

36 Sheet 36 of 38 Volumetric flaw in front of backwall PA-beam probe using angles -12 to 51 in steps of 7 Longitudinal wave 5 MHz Simulation of ultrasond images using RF data

37 Sheet 37 of 38 B-Scan Signal processing Probe: Array type with 16 Elements, Frequency 4 MHz, Angle of incidence 35 to 70 Transversal wave Measurements on specimen using phased array

38 Sheet 38 of 38 Thank you! Bundesanstalt für Materialforschung und -prüfung Fachgruppe VIII.4 Zerstörungsfreie Prüfung, elektrische Verfahren Unter den Eichen D Berlin Dipl.-Ing. Thomas Heckel ++49 (0) Thomas.Heckel@bam.de