KERN & SOHN HN-D - Manual (Page 6)

Sauter GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [email protected] Tel: +49-[0]7433- 9933-199
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Instruction Manual
HN-D
HN-D-BA-e-1213 6
A little coupling substance (i.e. Industry Vaseline) has to
be filled between the two components. Then the two parts
have to be pressed together. If the weight of the supporting
object is more than 5 kg, it can be replaced by the test
block.
5) Samples should be thick enough with sufficient layered
surface. If the D-type of impact sensor is used, the
thickness of the sample should be less than 5 mm and the
surface absorption layer (surface- hardening layer) should
not be less than 0.8 mm. To perform accurate hardness
measurements, the best way is to remove this layer before
testing.
6) If the testing sample surface isn’t horizontal and flat, the
curvature radius of the testing and nearby surface should
be larger than 30 mm. An appropriate supporting ring has
to be selected and installed.
7) A sample should not be magnetic. The signal of the
impact sensor would be seriously affected, which might
cause inaccurate test results.
A long operating life is provided by modern electronics with
power saving features. The large LCD display always
shows how HN-D Impact Hardness Tester is configured to
the tests. Variable function screen allows a quick change
of common test parameters. On the screen hint line the
other active control keys are positioned. No subjective
measuring errors are possible, highly repeatable results
are given to the user. Reliable test results are assured by
internal self diagnostics with error messages.
Readings can be stored automatically in the internal
memory or can be directly sent to a printer. PC evaluation
software allows for data analysis.
Tests in more points can be carried out by repeating the
above steps 1 to 4.
8. Troubles and solutions
If there may occur any other failures or defects, please
don’t hesitate to contact SAUTER GmbH. We will care for
your problems with the HN-D as soon as possible.
9. Maintenance and Service
9.1 Impact Device Maintenance
After 1000- 2000 times use, the impact device and the
impact body should be cleaned with a nylon brush. The
screw of the supporting ring has to be turned off before the
catheter can be cleaned. Then the impact body has to be
taken out and it has to be rotated into the tube with the
nylon brush in anti-clockwise direction. The brush has to
be pulled out when touching the bottom. This procedure
has to be repeated several times. Then the impact body
has to be loaded and the supporting ring reinstalled. The
impact body should be released after use. The use of any
lubricant is banned.
9.2 How to Store the Reports
Printing paper is thermal paper and it should be preserved
to avoid heat and direct light. If the print records are
necessary to be kept in long-term conservation, they
should be copied and preserved in time.
9.3 Normal Maintenance procedures
If the error is larger than 12HLD by calibrating the
hardness tester, the steel ball or the impact body has to be
renewed. Those parts may be worn out and this may lead
to failure in operation.
In case if any other abnormal phenomena occur to the
Hardness Tester, it should not be either demolished or any
fixed assembly parts may not be adjusted. Instead, just
contact our company, send your instrument to our address.
We will care for a prompt checking and if necessary, repair
of the device.
Appendix 1 Daily Checking
The test block (optional available) is mainly used to
calibrate the Hardness Tester. The error and repeatability
of it should be in the scope defined in following table:
Note:
HLD is the mean value of 5 Leeb Hardness values
measured on the test block.
HLD is the value marked on the test block.
is the maximum value of 5 Leeb Hardness values
measured on the test block.
ist he minimum value of 5 Leeb Hardness values
measured on the test block.
Appendix 2 Factors affecting the Accuracy
Incorrect operation or improper testing conditions can
seriously affect the accuracy. The following factors are the
main accounts in lack of accuracy:
1) Roughness of sample surface
When the impact body impacts on the sample, a small pit
will arise on the surface of it. The less roughness, the less
consumption of impact energy is needed. According to
this, the roughness of the surface should be Ra≤ 1.6.