MITECH MH660 User manual

MITECH CO., LTD.
www.mitech-ndt.com
www.ponpe.com

1
[e-mail]
CONTENTS
1 Introduction............................................................................................................................................................ 2
1.1 Features of the instrument......................................................................................................................... 2
1.2 Technical specifications..............................................................................................................................3
1.3 Standards and regulations applied...........................................................................................................3
1.4 Operating conditions...................................................................................................................................3
1.5 Application examples.................................................................................................................................. 3
1.6 Scope of delivery.........................................................................................................................................4
2 Product Feature.................................................................................................................................................... 4
2.1 Structure feature..........................................................................................................................................4
2.2 Impact device D........................................................................................................................................... 5
2.3 Other impact devices.................................................................................................................................. 5
2.4 Leeb rebound principle for hardness testing.......................................................................................... 5
2.5 Screen display............................................................................................................................................. 6
2.6 Keypad.......................................................................................................................................................... 6
2.7 Measuring conditions..................................................................................................................................7
3 Startup..................................................................................................................................................................... 7
3.1 Power supply................................................................................................................................................7
3.2 Connecting the instruments.......................................................................................................................7
3.3 Starting the instrument............................................................................................................................... 7
3.4 Configuration of the standby settings...................................................................................................... 8
4 Settings................................................................................................................................................................... 8
4.1 Test settings................................................................................................................................................. 9
4.2 Memory manager...................................................................................................................................... 12
4.3 Base calibration (Impact device calibration).........................................................................................12
4.4 Multi-point calibration............................................................................................................................... 13
4.5 System configuration................................................................................................................................ 14
4.6 HLX conversion function..........................................................................................................................16
4.7 Product information...................................................................................................................................17
4.8 Replace the batteries............................................................................................................................... 17
4.9 Communication..........................................................................................................................................17
4.10 Print via Bluetooth...................................................................................................................................17
5 Operation.............................................................................................................................................................. 18
5.1 Preparation of the sample....................................................................................................................... 18
5.2 Triggering the impact................................................................................................................................ 20
5.3 Conversion Deviations............................................................................................................................. 20
Number of impacts per measuring area...................................................................................................... 21
6 Fault and Troubleshooting.............................................................................................................................. 22
7 Maintenance, storage and care...................................................................................................................... 22
7.1 Performance check (before each use).................................................................................................. 22
7.2 Maintenance.............................................................................................................................................. 23
7.3 Transport and storage conditions...........................................................................................................23
7.4 Cleaning (after each use)........................................................................................................................ 24
7.5 Warranty..................................................................................................................................................... 24
7.6 Tips on safety.............................................................................................................................................24
Appendix.................................................................................................................................................................. 25
Table 1...................................................................................................................................... 25
Table 2...................................................................................................................................... 26
Table 3...................................................................................................................................... 27
Table 4...................................................................................................................................... 28
User Notes................................................................................................................................................................29
[email protected]

2
[e-mail]
1 Introduction
This hardness tester is designed for testing metallic materials, the hardness of which ranges from very
low to very high values. Hardness testing can be performed directly on-site and in any position. Typical
applications are large, heavy workpieces which could only be transported to a hardness testing machine
in a laboratory with great difficulty. It is especially suitable for applications in which standard indentation
hardness testing is either not feasible or not economical.
This hardness tester comprises an indicating device and an impact device. It is based on the rebound
hardness testing method according to Leeb. It is for testing the hardness of all material surfaces over a
large range of hardness quickly and independently.
1.1 Features of the instrument
The instrument represents a user-friendly microprocessor-controlled measuring system characterized by
the following benefits:
Wide measuring range
Based on the principle of Leeb rebound testing method, it can measure the hardness value of all metallic
materials. It can also measure the tensile strength of many metallic materials.
Impact device
Support seven types of impact device. Type of impact device automatically identified.
Impact direction correction
Impact direction automatically detected and corrected (after base calibration, except type G) , high
measuring accuracy in every impact direction, convenient measurement in any position.
Scale
Integrated conversion of the measured values to other popular hardness scales, e.g. HRC (Rockwell),
HRB, HV (Vickers), HB (Brinell), HS (Shore), HL (Leeb), Rm (Tensile strength for steel).
Calibration
Base calibration function and multi-point calibration function.
HLX conversion function
HLX conversion function to convert HLD values to HLC, HLG, HLDL and HLD+15, and vice versa.
Tolerance limit
Upper and lower limit can be set. It will alarm automatically when the test value exceeding the limit.
Display
Color TFT display (320×240 TFT LCD) with adjustable backlight, allow the user to work at worksites with
low visibility.
Memory
Integrated memory – Non-volatile, 500 series of measured values including each individual measured
value, mean value, testing date, impact direction, impact times, material and hardness scale etc..
Power saving
Two AA size alkaline batteries as the power source. Continuous operating period of no less than 100
hours (default brightness setting). Display Standby and Auto Power Off functions to save power.
Real time clock
The instrument clock keeps running tracking the time.
Communication
USB communication port. Online transfer of the measured data to PC or laptop via USB.
Printing
Built in Bluetooth module. Print test report wirelessly.
Robust design
Robust design allow the user to work at dusty worksites .
[email protected]
ponpe.com

3
[e-mail]
1.2 Technical specifications
The error and repeatability of the test value see the following table.
Table 1-1
No.
Impact
Device
Hardness value of the
test block
Measuring accuracy
Measuring
Repeatability
1
D
760±30HLD
530±40HLD
±6 HLD
±10 HLD
6 HLD
10 HLD
2
DC
760±30HLDC
530±40HLDC
±6 HLDC
±10 HLDC
6 HLD
10 HLD
3
DL
878±30HLDL
736±40HLDL
±12 HLDL
12 HLDL
4
D+15
766±30HLD+15
544±40HLD+15
±12 HLD+15
12 HLD+15
5
G
590±40HLG
500±40HLG
±12 HLG
12 HLG
6
E
725±30HLE
508±40HLE
±12 HLE
12 HLE
7
C
822±30HLC
590±40HLC
±12 HLC
12 HLC
Measuring range：170 to 960 HLD
Impact direction：360°. Auto detecting direction capability.
Built in conversion table from(to) HLD to(from) HLC、HLG、HLDL、HLD+15
Hardness Scale：HL、HB、HRB、HRC、HV、HS
Display：color TFT LCD，320×240 dots, adjustable backlight
Display of mean value, minimum value and maximum value.
Integrated data memory：500 measurement series.
Battery: two AA size, 1.5 Volt alkaline batteries
Continuous operating period：about 100 hours（with default brightness）
Communication：USB1.1; PC software is provided to transfer data between the instrument and PC.
Bluetooth support.
Multiple display languages (English, Chinese, etc.).
Weight: Approximately 220g.
Dimensions：120mm×67mm×31mm.
1.3 Standards and regulations applied
ASTM A956 (2006)、CNAL T0299 (2008)、JIS B7731 (2000)、DIN 50156 (2007)、DGZfP Guideline MC
1 (2008)、VDI / VDE Guideline 2616 Paper 1 (2002)、ISO 18625 (2003)、GB/T 17394 (1998)、JB/T 9378
(2001)、JJG 747 (1999).
1.4 Operating conditions
Operating temperature：-10℃～＋50℃;
Storage temperature：-30℃～＋60℃;
Humidity: ≤90％;
The surrounding environment should avoid of vibration, strong magnetic field, corrosive medium and
heavy dust.
1.5 Application examples
˗Hardness tests on already assembled machines or steel and cast constructions; e.g. on heavy and
large work pieces or on permanently installed system parts.
˗Rapid testing at many measuring points to examine the hardness over large areas.
˗Control measurement for rapid determination of a specific thermal treatment result; e.g. annealed or
quenched and tempered conditions.
[email protected]

4
[e-mail]
˗Testing of workpieces for which the test indentation should be as small as possible on sharp edges;
e.g. on rolls or grinded surfaces of machine parts.
˗Automatic hardness tests of mass-produced parts during manufacturing operation; e.g. automotive
industry.
1.6 Scope of delivery
Table 1-2
No.
Item
Qty
Remarks
Standard
config.
1
The main unit
1
2
Impact device D
1
With cable
3
Test block
1
4
Cleaning brush(I)
1
5
Small supporting ring
1
6
Battery
2
AA Size, Alkaline
7
Documents
1
Operating manual, Certificate
8
Carry case
1
9
Datapro Software
1
10
USB Cable
1
miniUSB-B to USB-A
Optional
config.
11
Cleaning brush(II)
For use with G type impact
device
12
Other type of impact devices
and support rings
Refer to Table 3 and Table 4 in
the appendix.
Note:
Test block – It is necessary to regularly conduct 3 to 10 test impacts on a reference hardness object to
verify the correct operation of the instrument. Various test blocks are available depending on the users’
hardness requirements. For added convenience, the test blocks also indicate the reference hardness
value in different hardness scales.
Support rings – Leeb Rebound testers only work correctly when the impact body is held at a proper
distance from the test surface during impact. The wide range of support rings permits testing on a great
variety of part geometries, i.e. flat surfaces, concave or convex cylindrical surfaces, spherical test
surfaces.
2 Product Feature
2.1 Structure feature
1,The main unit 2,Keypad 3,LCD display 4, Battery compartment
5,Socket of impact device 6, Bluetooth status 7,Impact device
8, Label 9, USB port
[email protected]
ponpe.com

5
[e-mail]
2.2 Impact device D
1,Release button 2,Loading tube 3,Guide tube 4,Coil unit
5,Connection cable 6,Support ring 7,Impact body
During measurement with this hardness tester, an impact body with a hard tip is impacted by spring
energy against the sample to be measured and then rebounds. During the impact, a permanent magnet
integrated in the impact body passed through a coil in which voltage is induced by the forwards and
backwards movement. This voltage is proportional to the velocities. The impact and rebound velocity is
measured when the impact body tip is approx. 1mm away from the sample to be measured. The
measuring signal is converted to the hardness value by the unit electronics, shown in the display and
stored in the unit memory (if set to strore).
2.3 Other impact devices
DC DL C D+15 E G
The main unit can be combined with any impact device to accommodate specific needs. Special impact
devices are available for use in confined spaces, with special component geometry or surface finish.
2.4 Leeb rebound principle for hardness testing
This hardness tester operates according to the Leeb principle, in which the hardness value is calculated
from comparing the energy of a test body before and after impacting on a sample.
The energy quotient is quoted in the hardness unit HL and is calculated
from comparing the impact and rebound velocities of the impact body. It
rebounds faster from harder samples than from softer ones, resulting in
a greater energy quotient which is defined as 1000×Vr/ Vi.
HL=1000×Vr/ Vi
Where,
HL— Leeb hardness value
Vr — Rebound velocity of the impact body
Vi — Impact velocity of the impact body
[email protected]

6
[e-mail]
2.5 Screen display
Below is the main screen of the main unit：
Material – Selected material.
Impact device – Type of impact device connected to the main unit
Impact direction – Impact direction setting (“AUTO” when automatically detecting the direction and auto
correction); Or detected impact direction after impact in auto direction mode.
File name – Next file name to store the measurement series.
USB status – Appears when the USB connection succeeds.
Time – Real time clock of the instrument system in HH:MM format.
Battery capacity – Shows the rest capacity of the batteries.
Measurements count – Number of measurements in a series.
Average times – Set number of measurements per series.
Test value – Shows last individual measured value before the test series closes; Or shows the average
measured value when the test series closes.
Scale – Hardness/Strength scale to display the test value.
Statistics – Shows minimum, maximum and average value of the test series.
Functions – Functions that can be executed. Functions are programmed and assigned to the function
keys F1 to F3. Note that the assignment of the function keys changes depending on the current
dialog/menu.
Testing operation could be carried out under this main screen. After each impact, it will display a singled
measured value; impact count plus one; the buzzer would alert a long howl if the measured value is not
within the tolerance limit. When reaching the average times, the buzzer will alert a long howl. After 1 to 2
seconds, the buzzer will alert a short howl, and display the average measured value.
2.6 Keypad
The instrument is designed to give the user quick access to all of the instrument’s functions. Its
easy-to-use menu system allows any function to be accessed with several key presses.
Function keys F1, F2 and F3.
Up arrow key - Navigate up; Increase values
Down arrow key - Navigate down; Decrease values
Selects and Confirms
Turn the main unit on or off; Cancel or close.
Selection of the test material.
Selection of the hardness scale. Displayed hardness scale
will affect all measurements in the current measurement series.
Changing the displayed hardness scale does not change the raw
data as measured in HL.
[email protected]
ponpe.com

7
[e-mail]
2.7 Measuring conditions
In order to avoid erroneous measurements:
˗Make sure that no heat or surface deformations occur at the testing point during the testing process.
˗Ensure the surface of the workpiece is clean, smooth and dry.
˗Ensure that the specimen is immobile and not subject to vibrations during the test (due to the
dynamic functioning of the hardness testing method). Thin parts must be specially fastened.
˗Use samples with large dimensions and enough mass if possible. Special measures must be taken
for specimens that weigh less than 5 kg.
˗Recommendation: Carry out at least 3 to 5 impacts at spaces of at least 3 to 5 mm at each
measuring point and use the average of the individual values.
˗Do not carry out an impact in an area that has already been deformed by another impact.
˗When preparing the surface, please observe that the condition of the material may be affected (e.g.
due to heating or cold working). As a consequence, the hardness is also influenced. If the surface is
inadequately prepared, the measuring results can be affected. Excessive surface roughness results
in lower HL values (the true hardness is greater than indicated) and broad variations of individual
measurements. Cold-worked surfaces produce excessively large HL values (the actual hardness is
less than measured).
3 Startup
3.1 Power supply
Two AA size alkaline batteries are needed as the power supply.
The battery compartment is situated at the instrument back. The cover is fastened with two screws. To
insert the batteries:
Loosen the two screws of the battery cover.
Lift the cover off upward.
Insert the batteries into the battery compartment.
Close the battery compartment and fasten the screws.
Turn on the instrument to make sure the battery is installed correctly and firmly.
3.2 Connecting the instruments
To prepare the instrument for operation, you have to connect an impact device to it. The instrument is
available with the Lemo socket connectors.
When connecting an impact device to the instrument, it’s not only important that the physical connection
be properly made. It’s also important that the instrument is properly configured to work with the installed
impact device.
3.3 Starting the instrument
To start the instrument, press down key until display activates. While the device is booting a splash
screen, the serial number of the unit, the installed software version, the date and time of the system
appear on the display.
The start display of the instrument appears as right
figure.
Press F1 key to change to a different language.
Press F3 key to skip the booting check process and enter
the measure mode immediately.
[email protected]

8
[e-mail]
The instrument carries out a self-check and then
switches over to the measure mode automatically if there
is no key operation.
The instrument is now ready for the first measurement.
The instrument will automatically reload last settings. It has a special memory that retains all of its
settings even when the power is off.
The type of connected impact device will be detected automatically if the impact device setting is “AUTO”.
User should check if the type of the impact device is correct. If the type of the impact device is incorrect,
change the setting or check the connection.
Probe specific parameters must be measured again if the impact body has been changed, or hardness
test shows deviations greater than ±6 HLD from the nominal value. Recalibration of the probe is
recommended if: the impact device has been cleaned; the impact device has not been used for a longer
time; or particular high accuracy is required. Refer to 4.3 for details.
To shut off the instrument, keep pressing down key until shutting down message appears.
Note:The instrument will shut off automatically if the battery capacity level is too low.
3.4 Configuration of the standby settings
To save battery power, the device supports the following power states:
Run state – The main unit is running at full frequency
Standby state – After 5 seconds (default setting) the brightness of the LCD display is tuned to a low
level and the CPU is running at reduced frequency. This has no effects on the data or the memories.
Pressing any key or performing a measurement sets the unit back to run state and the brightness is
tuned back.
Power off state – After 2 minutes (default setting) the instrument changes from standby state to power
off state. The main unit and the display is switched off and consumes almost no energy. Pressing any
key will stop the unit entering power off state while it prompts out “Idle Timeout!” and return back to run
state.
The change from run state to standby state is controlled by display standby delay setting. The time delay
can be configured by the user in the Display Standby Delay dialog box. The main unit can be reset to run
state by any user activity while in standby state.
4 Settings
On the main screen, press F3 key to open the main menu. Navigate with arrow keys through the menu
items.
Structure of the menus:
[email protected]
ponpe.com

9
[e-mail]
Note: If a specific menu item is disabled (appears in a different color), the high light cursor will
skip that item while navigating.
4.1 Test settings
Press arrow keys or F2 key to navigate up and down to
highlight the desired item.
Press or F3 key to change the setting or open the
setting dialog.
Press or F1 key to return to the main menu.
Preselected parameters of test setting:
˗Impact device – Automatically identified.
˗Impact direction – Automatically detected and corrected.
˗Material – Steel and cast steel
˗Hardness scale – HLD (if available for connected impact device type)
˗Average times – three
4.1.1 Impact device setting
The impact device setting can be fixed to a specific type of impact device depending on the one
connected to the main unit. As an alternative, AUTO item can also be selected to identify the type of the
impact device automatically.
Press arrow keys or F2 key to navigate up and down to
highlight the desired item.
Press or F3 key to confirm the selection.
Press key to cancel the change and close current
dialog box.
Make sure the selected or the automatically identified impacted device agrees with the connected one.
[email protected]