Important information on ultrasonic testing
1 Introduction
Krautkrämer USM 100
Rev. - (09/2021)
27
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.
Ultrasonic evaluation of flaws
In present-day test practice, there are basically two dif-
ferent methods of flaw evaluation:
If the diameter of the sound beam is smaller than the ex-
tent of the flaw, then the sound beam can be used to ex-
plore the boundaries of the flaw and thus determine its
area.
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.
Summary of Contents for Krautkramer USM 10
Page 1: ...Krautkr mer USM 100 Operating Manual Id No 160M4395 Rev 09 2021...
Page 18: ...18 Rev 09 2021 Krautkr mer USM 100...
Page 19: ...Krautkr mer USM 100 Rev 09 2021 19 Introduction 1...
Page 34: ...1 Introduction How to use this manual 34 Rev 09 2021 Krautkr mer USM 100...
Page 35: ...Krautkr mer USM 100 Rev 09 2021 35 Standard package and accessories 2...
Page 43: ...Krautkr mer USM 100 Rev 09 2021 43 Initial start up 3...
Page 59: ...Krautkr mer USM 100 Rev 09 2021 59 Principles of operation 4...
Page 94: ...4 Principles of operation Multi color LED 94 Rev 09 2021 Krautkr mer USM 100...
Page 95: ...Krautkr mer USM 100 Rev 09 2021 95 Operation 5...
Page 177: ...Krautkr mer USM 100 Rev 09 2021 177 Documentation 6...
Page 191: ...Krautkr mer USM 100 Rev 09 2021 191 Maintenance and care 7...
Page 199: ...Krautkr mer USM 100 Rev 09 2021 199 Interfaces and Peripherals 8...
Page 205: ...Krautkr mer USM 100 Rev 09 2021 205 Appendix 9...
Page 219: ...Krautkr mer USM 100 Rev 09 2021 219 Specifications 10...
Page 225: ...Krautkr mer USM 100 Rev 09 2021 225 Index 11...
Page 241: ...11 Index Krautkr mer USM 100 Rev 09 2021 241...
