Checkline TI-UMX2 - Manual (Page 25)

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different inherent sound velocities. For example, the velocity of sound through steel
is about 0.233 inches per microsecond, versus that of aluminum, which is about 0.248
inches per microsecond. If the gauge is not set to the correct sound velocity, all of the
measurements the gauge makes will be erroneous by some fixed percentage.
The TI-UMX2 has 8 preset material types with common fixed velocities to select
from. There is also 1 custom programmable velocity available for non-standard known
material velocities.
Basic Material Type
In order to calibrate the TI-UMX2 according to a specific material to be tested, the user
can select a basic material type from a list with approximate velocity values according
to various material types. It’s important to note that these velocities will not always be
an exact representation of the material being tested. They will typically be more than
adequate฀for฀ongoing฀‘historical’฀material฀degradation฀inspections.฀The฀following฀is฀a฀
list of the preset materials, and the procedure to select and calibrate the TI-UMX2:
1. Press and hold the single TI-UMX2 button, located on the top end cap, until the top
level menu options begin scrolling on the alpha display. Once this occurs, the button
can now be released. The menu options will scroll one to the next in a time delayed
sequence, and will display all the menu options in a
continuous loop.
2. When MATL is displayed, immediately press and
release the button to enter the sub menu options. Again, the options will begin
scrolling in a continuous loop.
TI-UMX2 Material Chart
Material Types Abbreviations Velocity in/msec Velocity m/sec
Aluminum RLU 0.2500 6350
Steel (4340 Mild) STL 0.2330 5918
Stainless Steel (304) STLSTL 0.2229 5662
Iron IRON 0.2320 5893
Cast Iron CIRO 0.1800 4572
PVC PVC 0.0940 2388
Polystyrene PLST 0.0920 2337
Poly Urethane PLUR 0.0700 1778
Custom CUSTOM USER USER
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10.0 Pulse-eCHo CoaTInG & CoaTInG TeCHnIQues
10.1 Introduction to Pulse-echo Coating Measurement (PeCT)
In the previous sections we’ve discussed the need for detecting pits and flaws (pulse-
echo) in materials, along with the requirement to measure through and eliminate errors
caused by coated materials (echo-echo). Until now, both modes were needed in order
accomplish both tasks. Pulse-echo mode was used for flaw detection, and echo-echo
mode was used to eliminate the coating thickness and provide a nominal material
thickness only. With this in mind, it often became cumbersome toggling between both
modes respectively.
In a majority of applications involving coated materials, inspectors are often interested
in monitoring both the thickness of the material, as well as the thickness of the coating.
Therefore, the TI-UMX2 has been designed to provide the user with the ability to
measure the material and coating thicknesses simultaneously, while maintaining the
ability to detect flaws and pits all in a single mode called Pulse-Echo Coating (PECT).
This฀is฀accomplished฀by฀using฀a฀custom฀hybrid฀combination฀mode฀utilizing฀properties฀
from the basic modes along with a group of special techniques and theoretical wave
phenomena’s.
The฀TI-UMX2฀is฀preset฀to฀a฀coating฀velocity฀of฀0.0850฀in/µsec฀(2159฀m/sec)฀from฀the฀
factory. This velocity is a very close approximation of the common coating velocities
found฀in฀the฀ield.฀However,฀this฀can฀be฀changed฀to฀another฀known฀coating฀velocity,฀
using฀DataComm฀utility฀software฀to฀set฀a฀‘custom’฀velocity฀that฀can฀be฀uploaded฀to฀the฀
TI-UMX2.
10.2 enabling Pulse-echo Coating Mode (PeCT)
The฀special฀PECT฀mode฀is฀only฀available฀for฀use฀with฀‘dual฀element’฀transducers.฀When฀
the TI-UMX2 is initially powered up, the gauge will automatically check to see if the
transducer฀plugged฀into฀the฀gauge฀can฀be฀recognized.฀All฀Electromatic฀Equipment฀
Company coating enabled transducers are equipped with the auto recognition feature. If
the฀TI-UMX2฀doesn’t฀recognize฀that฀a฀special฀coating฀enabled฀transducer฀is฀plugged฀into฀
the gauge, the coating feature will be disabled entirely. There are a number of coating
enabled transducers available from Dakota. Please contact us with your application
requirements for additional information on frequencies and diameters currently offered.
noTe: When PECT mode is used, the coating value cannot be viewed on the
TI-UMX2.฀Only฀the฀base฀material฀thickness฀is฀displayed.฀However,฀if฀the฀measurements฀
are stored to a file and downloaded to a PC, the coating measurements can be viewed
as they are saved within the file. The actual A-Scan waveform is also stored in the file.
This can prove very valuable, as it provides the inspector additional confidence that the
measurement was successful overall. Finally, all TI-UMX2 settings are also saved for
each individual reading, again offering confidence and detail for reporting
The following procedure demonstrates how to enable PECT mode: