KERN & SOHN HMR User Manual

Sauter GmbH

Ziegelei 1
D-72336 Balingen
E-Mail: [e-mail]

Tel: +49-[0]7433- 9933-199
Fax: +49-[0]7433-9933-149
Internet: www.sauter.eu

Instruction Manual

HMR

DIGITAL LEEB HARDNESS TESTER

Model: HMR

Table of contents

1. Overview

1.1 HMR Advantages

1.2 Main Application & Testing Range

1.2.1 Main Application

1.2.2 Testing Range

1.3 Configuration

1.4 Working Conditions

2. Structure Feature & Testing Principle

2.1 Structure Feature

2.1.1 Hardness Tester Appearance

2.1.2 Parts of the Main body

2.1.3 D Type Impact Device

2.1.4 Different types of Impact Devices

2.2 Leeb Hardness Testing Principle

3. Technical Specifications

4. Preparation & Testing

4.1 Preparation and Inspection before Testing

4.1.1 Preparation of Sample Surface

4.1.2 System Setting

4.1.3 Presetting Testing conditions

4.2 Testing Program

4.2.1 Start-up

4.2.2 Testing

4.2.3 Reading the Measured Value

4.2.4 Power Off

5. Advice

6. Operation in Details

6.1 Power On

6.2 Power Off

6.3 Testing

6.3.1 Full description of the Main Display

6.3.2 Testing Operation at the Main Display

6.3.3 Key Operation at the Main Display

6.4 Menu Structure

6.5 Test Set

6.5.1 Impact Direction Setting

6.5.2 Average Times Setting

6.5.3 Material Setting

6.5.4 Hardness Scale Setting

6.5.5 Tolerance Limit Setting

6.5.6 Hardness / б b Setting

6.6 Print Set

6.7 Memory Management

6.7.1 View from No.1 Group/ View from Ending Group

6.7.2 View from Selected No. Group

6.7.3 Data Transfer

6.7.4 Delete by Group No.

6.7.5 Delete all Data

6.7.6 Deletion Confirmation

6.8 Browsing Memory Data Groups

6.9 System Reset

6.9.1 LCD Brightness Setting

6.9.2 Date/ Time Setting

6.10 Software Information

6.11 System Calibration

6.12 EL Background Light

6.13 Auto Power Off

6.14 Battery Replacement

6.15 Connection of Data Transmission Cable

7. Fault Analysis & Fault Clearance

8. Servicing & Maintenance

8.1 Impact Device Servicing

8.2 Normal Maintenance Program

9. Calibration

10. Transport and Storage Conditions

11. Declaration of Conformity
APPENDIX
Table 1
Table 2
Table 3
Table 4

1. Overview

1.1 HMR Advantages

 Wide measuring range based on the principle of

Leeb Hardness testing theory. Leeb Hardness of
all metallic materials can be measured.

 Large screen (128 x 64 dot matrix LCD) showing

all functions and parameters.

 Testing at any angle, even upside down
 With EL background light
 Direct display of hardness scales HRB, HRC,

HV, HB, HS, HL

 Seven impact devices are available for special

applications. Automatical identification of type of
impact devices

 Large capacity memory can store 500 groups,

information including single measured value,
mean value, testing date, impact direction,
impact times, material, hardness scale etc.

 Upper and lower limit can be preset. It will alarm

automatically if the result value is exceeding the
limit.

 Battery information: rest capacity of battery is

indicated.

HMR-BA-e-1212 1

Sauter GmbH

Ziegelei 1
D-72336 Balingen
E-Mail: [e-mail]

Tel: +49-[0]7433- 9933-199
Fax: +49-[0]7433-9933-149
Internet: www.sauter.eu

Instruction Manual

HMR

No.

Item

Qua
ntity

Remarks

Stan
dard
Config
uration

1

Main body

1

2

D type impact
device

1

With cable

3

Standard test
block

1 4

Cleaning brush
(I)

1

5

Small support
ring

1
6

Alkaline battery

4

AA size

7

Manual

1 8

Instrument case

1 9

Optio
nal
Config
uration

11

Cleaning brush
(II)

1

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.

13

DataPro for
HL200 software

1 14

Communication
cable

1

 Software calibration function
 Software to connect with PC and USB port
 Compact metal case, suitable for use under poor

working conditions

 Continuous working period of not less than 50

hours with two Alkaline batteries (AA size);

 Auto Power Off to save energy
 Dimensions: 132 mm x 76.2 mm
 Weight: 345 g

1.2 Main Application & Testing Range

1.2.1 Main Application

 Die cavity of molds
 Bearings and other parts
 Failure analysis of pressure vessels, steam

generators and other equipment

 Heavy work piece
 Testing the surface of a small hollow space
 Material identification in the range of metallic

materials

1.2.2 Testing Range

Please refer to Table 1 and Table 2 in the APPENDIX.

1.3 Configuration

Table 1-1

2. Structure Feature & Testing Principle

2.1 Structure Feature

2.1.1 Hardness Tester Appearance

1. Main body 2.Impact device

2.1.2 Parts of the Main body

1.4 Working Conditions

Working Temperature: 0°C up to +40°C
Storage Temperature: -30°C up to +60°C
Relative humidity: ≤ 90%
Vibrations, strong magnetic field, corrosive medium and
heavy dust should be avoided in the surroundings.

HMR-BA-e-1212 2

1 Socket of USB
2 Aluminium case
3 Belt hole
4 Battery cover
5 Keypad
6 LCD Display
7 Socket of Impact Device
8 Aluminium case, (backside)
9 Label (backside)

2.1.3 D Type of Impact Device

1. Release button

2. Loading Tube

Sauter GmbH

Ziegelei 1
D-72336 Balingen
E-Mail: [e-mail]

Tel: +49-[0]7433- 9933-199
Fax: +49-[0]7433-9933-149
Internet: www.sauter.eu

Instruction Manual

HMR

N
o
.

Typ
e of
im
pact
devi
ce

Hardness value
of Leeb
standard
hardness block

Error of
displayed
value

Repeata
bility

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

3. Guide Tube

4. Coil unit

5. Connection cable

6. Impact body

7. Support ring

2.1.4 Different types of Impact Devices

2.2 Leeb Hardness Testing Principle

The basic testing principle is to use an impact body of a
certain weight which impacts against the testing surface
under certain test force. The impact velocity and the
rebound velocity of the impact body are measured
respectively when the spherical test tip is located 1mm
above the surface being tested.
The calculation formula is as follows:

HL= 1000 x VB/VA

Where HL= Leeb Hardness Value
VB= Rebounding velocity of the impact body
VA= Impact velocity of the impact body

3. Technical Specifications

 Error and repeatability of the displayed value,

see Table 3-1:

HMR-BA-e-1212 3

 Measuring range: HLD: (170 ~ 960) HLD
 Measuring direction: 0 ~ 360°
 Hardness Scale: HL, HB, HRB, HRC, HRA,

HV, HS

 Display: dot matrix LCD,128 x 64 dots
 Data memory: max. 500 groups
 Power supply: 3V, (2AA size Alkaline batteries)
 Continuous working period: about 50 hours

(with backlight off)

 Communication interface: USB1.1

4. Preparation & Testing

4.1 Preparation and Inspection before Testing

4.1.1 Preparation of Sample Surface

Preparation of the sample surface should conform to the
relative requirements in APPENDIX Table 3.

 During the preparation of the sample surface,

any heating or cold processing on this surface
should be avoided.

 Too big roughness of the surface being

measured could cause errors. The surface of the
sample should show metallic luster, be smooth
and polished, without any stains of oil etc.

 Support of the sample is not necessary for

heavy objects. Medium-weight samples have to
be placed onto a smooth and stable plane. It
must be placed in absolute equability and
without any wobble.

 Curved surface: The best testing surface, of

course, is flat. When the curvature radius R of
the surface to be tested is smaller than 30 mm
(D, DC, D+15, C, E and DL type of impact
device) and smaller than 50 mm (G type of
impact device), the small support rings should
be chosen.

 The sample should have enough thickness, the

minimum thickness of it should conform to
Table 3.
*For a sample with a hardened layer on its surface,
the depth of the hardened layer should also conform
to Table 3.

 Coupling: Light-weight samples must be firmly

coupled with a heavy base plate. Both coupled

surfaces have to be flat and smooth; there may

not rest any redundant coupling agent. The

impact direction must be vertical to the coupled

Sauter GmbH

Ziegelei 1
D-72336 Balingen
E-Mail: [e-mail]

Tel: +49-[0]7433- 9933-199
Fax: +49-[0]7433-9933-149
Internet: www.sauter.eu

Instruction Manual

HMR

surface. If the sample is a big plate, long rod or
bending piece, it can be deformed and become
unstable, even though its weight and thickness
is big enough; accordingly, the test value might
not be accurate. So the sample should be
reinforced or supported at its back.

 Magnetism of the sample itself should be

avoided.

4.1.2 System Setting

See 6.9 for details.

4.1.3 Presetting Testing conditions

See 6.5 for details.

4.2 Testing Program

The hardness tester has to be verificated by using the
hardness block. The error and repeatability of the
displayed value should be within the regulation of
APPENDIX Table 2.

4.2.1 Start-up

1) The plug of the impact device has to be inserted into the
socket of the impact device of the instrument.

2) The key has to be pressed to power on. Now the
instrument is in testing condition.

4.2.2 Testing

- The release button on the upside of the impact device
has to be pressed to start testing. The sample and the
impact device as well as the operator are all required to be
stable now. The action direction should pass the axis of
the impact device.

- Each measurement area of the sample usually needs 3
to 5 times of testing operations. The result data dispersion
should not be more than the mean value ± 15 HL.

- The distance between any two impact points or from the
centre of any impact point to the edge of the sample
should conform to the regulation of Table 4-1.

- If an accurate conversion from the Leeb hardness value
to another hardness value is requested, a contrastive test
is needed to get conversion relations for the special
material. An inspected qualified Leeb hardness tester and
a corresponding hardness tester have to be used to test at
the same sample respectively. For each hardness value,
each homogeneous measurement, 5 points of Leeb
hardness value are needed. They are in the surroundings
of more than three indentations which need conversion of
hardness. The Leeb hardness arithmetic average value
and the corresponding hardness average value as
correlative value respectively are used to establish an
individual hardness contrastive curve. The contrastive

curve at least should include three groups of correlative
data.
Table 4-1

4.2.3 Reading the Measured Value

4.2.4 Power Off

The key has to be pressed to power off.

5. Advice

- The impact device must be replaced during the
instrument is powered off. Otherwise the type of impact
device cannot be identified by the main body. The circuit
board of the main body may get damaged.

- If the testing times are less than the preset times value,
the current test value can not be saved. 【 AVG 】 can be
pressed to end the testing process in advance if the values
shall be saved.

- When pressing 【 AVG 】 to end testing in advance, the
【 Auto save】 , 【 Auto transfer】 settings will not work.

- Only D and DC type of impact device have got the
function of strength measurement. Using other types of
impact device, the 【 Set hardness orбb 】 can not be
modified. The 【 Set hardness orбb 】 setting will be set
to【 Hardness 】 automatically after replacing the impact
device, whether the setting is【 Hardness 】 or not before.

- Not all materials can be converted to all hardness style
values. The hardness style is reset to HL automatically
after changing material. So, material has to be selected
first before changing the hardness style.

6. Operation in Details

6.1 Power On

The key has to be pressed to power on the instrument.
Following is shown on the screen:

The type of impact device will automatically be detected
during powering on. This information will be displayed on
the screen (Probe Type). After several seconds, the

HMR-BA-e-1212 4