OPERATION INSTRUCTION

OF

LEEB

MULTIFUNCTIONAL

HARDNESS TESTER

2  

CONTENTS

1、 GENERAL DESCRIPTION························3

2、 TEST PRINCIPLE·······························3

3、 FUNCTION AND APPLICATION··················4

4、 STRUCTURE DESCRIPTION·····················10

5、 OPERATING METHOD AND NOTICES············10

3  

Ⅰ.GENERAL DESCRIPTION

Leeb Hardness Tester is a new type of portable, multifunctional,

dynamic hardness measuring instrument. it is designed adopting

advanced technology of microprocessor Leeb Hardness Tester features

high accuracy, reliable performance, small size, wide measuring range

and easy operation, etc. It is suitable for quick hardness measurement of

metal materials, especially suitable for site measurement of large-size

parts and difficult-to-dismantle components. It can automatically convert

the HL hardness values into the hardness of Brinell. Rockwell, Vickers

and Shore according to different materials and directions and then record.

And it is indeed a desired hardness measuring instrument.

Ⅱ.TEST PRINCIPLE

Hardness measurement carried out by Leeb Hardness Tester is a

dynamic method which is on the basis of the principle of energy

measurement. During a hardness test, an impact body, equipped with

tungsten carbide test ball, impacts under spring force against the test

surface and then rebounds from the surface. Impact and rebound

velocities are measured in a contactless manner. That means it is

accomplished by the Coil in the impact device and the permanent magnet

built in the impact body. During impact, the magnet passes through the coil,

impact and rebound movements induce electromotance in the coil, the

electromotance is proportional to the velocities. The signals are checked and

processed into Leeb hardness value .The conversion formula is as follows:

HL=1000×

HL----Leeb hardness Va

Vr

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Vr----rebound velocity of impact body (peak point voltage)

Va----impact velocity of impact body (peak point voltage)

When different impact devices are adopted, the achieved Leeb hardness

value should be marked with relevant symbol after them, such as 800HLD,

800HLG, etc.

The measured Leeb hardness values when different impact devices are

adopted should not be replaced with each other .For example:

800HLD≠800HLG.

Converting Leeb hardness into other harness, different impact devices

ask for different conversion relations.

The hardness converted from the Leeb one should be written as follows, for

example:

The Rockwell hardness value of scale C measured by type D impact

device should be written as 40.5HRCLD; The Brinell hardness value measured

by type D+15 impact device should be written as450HBLD+15;The type D

Shore hardness value measured by type C impact device should be written as

56.2 HSDLC.

Ⅲ. FUNCTION AND APPLICATION

1. Main Application

·Hardness measurement of products for mass producing.

·Site hardness test for machinery of heavy parts.

·Hardness measurement of heavy parts.

·Hardness measurement of the mould cavity.

·Hardness measurement of small space machinery.

·Failure analysis of equipment.

·Distinguishing metal materials in stock.

·Hardness controlling test for the heat treatment of anneal, temper, quench,

5  

etc.

2. Main Technical Specifications

Measuring accuracy: In the same measuring range, the measuring

average error of multiple test value are not greater than ±0.8%(relative

to the range HL800±50).When automatically converting into the

hardness values of Brinell (HB), Rockwell (HRB,HRC), the measuring

error is ±3%～±12.5%.When converting into shore hardness

value(HSD), the measuring error is ±1.5%～±4.5%.

Working temperature:0—40℃

Working voltage:4.7—6.0V DC

Test direction: Arbitrary

Weight: 0.67kg (Standard disposition: hardness tester + D type impact

device)

Dimensions (L x W x H):268x86x47mm

Once charged working time: approx. 24 hours

3. Main Function

·During the test, the illumination can be turned on or shut off at any

needed time.

·Test date can be preset by the keyboard.

·Test directions and test materials can be preset by the keyboard.

·5 types of impact devices (D,DC,D+15,C,G)can be equipped.

·6 kinds of hardness(HL,HRB,HRC,HB,HV,HSD)can be converted into

each other, the hardness and tensile strength can also be converted into

each other.

·It can print out test results as many as wanted and the greater errors

6  

can be canceled.

·The present test mode and measured value can be displayed by

full screen.

·Last group of measured values and all the preset parameters can

be recorded after the machine is shut off.

·Battery voltage can be tested automatically. When the working

voltage is lower than the rated value, the characters displayed

on the screen flash alarming.

4. Impact Device

The hardness tester can be equipped with 5different kinds of impact

devices. Type D is the base one and the other 4 types apply to various

special hardness tests.

·Type D impact device: Applied to most hardness tests.

·Type DC impact device: Suitable for inner hole and inner cylinder

hardness tests.

·Type D+15 impact device：Suitable of hardness test of furrow or

concave surface.

·Type C impact device: Suitable for hardness measuring of

surface-hardened parts, surface-covered layer and thin wall.

·Type G impact device : Only suitable for hardness measuring of

dense parts whose Brinell hardness is not higher than 650HB.

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5. Specifications of impact Device

Specifications Type of Impact Device

D,DC D+15 G C

Mass of impact Body(g) 5.5 7.8 20.0 3.0

Impact Energy(N.mm) 11.0 11.0 90.0 2.7

Diameter of Impact Ball

(mm)

3.0 3.0 5.0 3.0

Diameter of Impact Device

(mm)

20.0 20.0 30.0 20.0

Length of Impact

Device(mm)

150/85 165 250 140

Materials of Impact body

top (mm)

tungsten

carbide

tungsten

carbide

tungsten

carbide

tungsten

carbide

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6. Measurement and Conversion Range

Impact Device

D,DC

LD: 200～900

HRC HRB HB HV HSD

Steel and cast steel 17.9-68.5 59.6-99.5 80-647 80-940 32.5-99.5

Alloy Tool Steel 20.4-67.1 80-898

Gray Cast-iron 93-334

Nodular Graphite

Cast Iron

131-387

Cast Aluminium

Alloy

30-159

Pinchbeck Alloy

(Brass)

13.5-95.3 40-173

Copper-tin Alloy

(Bronze)

60-290

Pure Copper 45-315

Impact Device D+15 LD+15: 300～900

HRC HRB HB HV HSD

Steel and Cast Steel 19.3-67.9 90-638 80-937 33.3-99.3

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Impact Device C LC: 350～950

HRC HRB HB HV HSD

Steel and Cast Steel 20.0-69.5 80-683 80-957 31.1-99.6

Impact Device G LG: 300～750

HRC HRB HB HV HSD

Steel and Cast Steel 46.4-99.2 90-646

Gray Cast-iron 92-326

Nodular Graphite Cast

Iron

127-364

NO. Materials LD B(Mpa)

1 Carbon Steel 622-720 1192-1710

2 Chromium Steel 622-736 1146-1845

3 Chrome-vanadium Steel 622-757 1165-1993

4 Chrome-nickel Steel 622-753 1142-1986

5 Chrome-molybdenum Steel 622-745 1139-1888

6 Chrome-nickel-molybdenum Steel 622-745 1171-1947

7 Chromansil Steel 622-753 1155-1971

8 Stainless Steel 622-720 1145-1725

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IV. STRUCTURE DESCRIPTION:

V. OPERATING METHOD AND NOTICES:

1. Sample Preparation

(1)Surface preparation

During preparing the surface of the sample, great care must be taken to

avoid the change of the surface hardness caused by heat or cold treatment.

During the course of processing, if the surface is too hot, the hardness of the

material will be usually lowered, on the contrary, the hardness will be higher.

The roughness of the sample surface is a very important requirement. If the

roughness is too great, the Leeb hardness values of the values of the surface

will be lower and differ too much to each other because of the surface

deforming too much and absorbing too much impact energy. So the surface of

the sample must be smooth or grinded.

(2)Curve Surface

During the test of the curve surface sample whose curvature radius R is less

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than 30mm (Impact Device type D, DC, D+15, C) and 50mm (Impact Device

the type G), an special positioning cap is needed.

For the convenient tests of various special curve surfaces, choose the

supporting ring for different impact devices according to the following table.

NO. Model Note

1 R10-15 Measuring outside surface of cylinder

R10-R15

2 R14.5-30 Measuring outside surface of cylinder

R14.5-R30

3 ZY11-13 Measuring inside surface of cylinder

R11-R13

4 ZY12.5-17 Measuring inside surface of cylinder

R12.5-R17

5 ZY16.5-30 Measuring inside surface of cylinder

R16.5-R30

6 QR10-15 Measuring outside spherical surface

SR10-SR15

7 QR14.5-30 Measuring outside spherical surface

SR14.5-SR30

8 ZHR11-13 Measuring inside spherical surface SR11-SR13

9 ZHR12.5-17 Measuring inside spherical surface

SR12.5-SR17

10 ZHR16.5-30 Measuring inside spherical surface

SR16.5-SR30

11 TC Measuring outside surface of cylinder

Adjustable Radius

R10-∞

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(3) Support of Test Sample

For heavy samples, support is not necessary.

For medium size , they must be absolutely steadily put on the smooth and

fixed flat surface.

For light samples, they must be coupled with the fixed supporting unit.

The coupling surface must be flat and smooth. The couplant should not

be too much and the test direction must be vertical to the coupling surface.

When testing large size samples such as large area plate, long rod, curve

piece, even the sample is fairly heavy and thick, the sample may also be

deformed causing incorrect hardness. So the back of the test position

should be supported and fixed.

(4)Sample should not be magnetic for itself

Corresponding to various impact devices, the weight and thickness of

sample surface is requested to be as follows;

Sample

Impact Device

Weight of Sample(kg) Minimum

Thickness(mm) Light Medium Heavy

Need to

be

Coupled

Need to

be

Fixed

Directly Sample Hardened

Layer

D,DC,D+15 0.05-2 2-5 >5 3 0.8

G 0.5-5 5-15 >15 10

C 0.02-0.0

5

0.5-1.5 >1.5 1 0.2

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Corresponding to various impact devices, the surface roughness of sample is

requested to be as follows;

Type of Impact

Device

Sample Surface

Roughness Ra

Corresponding

Original National

Standard

ISO

Standard

D,DC,D+15 2um ▽6 N7

G 7um ▽4 N9

C 0.4um ▽8 N5

2. Operation Instruction:

Function area diagram of LCD screen

7 8 9 PAPER

FEED

PRINT

4 5 6 LAMP

ENTER

AVERAGE

DELETE

1 2 3 SET

DATE

H

δ b

0

SENSOR DIRECTION MATERIAL

Diagram of the keyboard function

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(1) Starting

Insert the cable plug of the Impact Device into the input receptacle, press

the power switch and the machine is turned on. After one second, if the

tester is used for the first time, the three numerals displayed in the value

display area are “000”(from right), test time area displays “0”, hardness

type area displays “HL”, test direction is. “↓”, material symbol area

displays“1”. If it is not firstly used, all the areas Display the mode of last

test. If the testing parameters that you need coincide with the present

mode, the test may be started. Otherwise, reset the parameters through

the keyboard.

(2) Set test parameter

Set test date

Press the key “SET DATE”, value display area will display“y00”, then

the year (4 numerals) may be input. After that it will display “n00”, when

the month (2 numerals) may be input. Then after the mouth, it

displays“d00” and the day (2 numerals) may be input. Now the date is set.

After the date is set, if you press the key “ SET DATE ” again, the screen

displays the mode before being set.

·Set impact direction

Set this parameter according to the actual impact direction of the

impact device when measuring.

Press the key “DIRECTION”, there are 5 impact directions to be chosen.

horizontally slantly down vertically down slantly up vertically up

→ → → ↙ → ↓ → ↖ → ↑

The set parameter will display the relevant impact direction in the

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direction display area.

· Set hardness type and tensile strength (shorten as

“strength ”thereinafter)

Press “H/δ b” key and there will be 6 kinds of hardness and strength to be

chosen.

Leeb Brinell Vickers Rockwell C Rockwell B Shore D Strength

HL HB HV HRC HRB HSD 0b

The set parameters will display the relevant hardness and tensile strength

in the display area and the value area will show the number.

·Set material

Press the key “MATERIAL” and there are 8 kinds of materials that can

be chosen cyclically.

Material symbol area shows the symbol of the chosen material and

value display area displays the number corresponding to the chosen

material.

The materials corresponding to the material symbol are as follows:

Material

Symbol

1 2 3 4

Measuring

Hardness

Steel and

Cast Steel

Alloy Tool

Steel

Gray

Cast-iron

Nodular

Graphite

Cast Iron

Measuring

Strength

Carbon

Steel

Chromium

Steel

Chrome-

Vanadium

Steel

Chrome-

Nickel Steel

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Material

Symbol

5 6 7 8

Measurin

g

Hardness

Cast Aluminium

Alloy

Pinchbeck

Alloy

(Brass)

Copper-tin

Alloy

(Bronze)

Pure

Copper

Measurin

g Strength

Chrome-molybdenu

m

Steel

Chrome-nickel

-

Molybdenum

Steel

Chromansi

l Steel

Stainles

s Steel

·Set impact device

Press the key“0/SENSOR” and there are 5 types of Impact Devices (D,

DC, D+15, C, G) that can be chosen cyclically.

Note: If the customer asks the tester only to be equipped with type D

impact device, the function will have been canceled before supplying.

(3) Measurement

If it is necessary, the tester may be tested by standardized test block

before using.

·Loading

Push down the loading jacket to lock the impact body.

·Positioning

Tightly press the support ring (which is at the lower part of the impact

body) on the sample surface, the distance between two testing positions

should be not less than 3mm.

·Starting

Press the release button ( which is on the top of the impact body)to

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have test. The test piece, impact device and operator should all be

steady. The apply force direction should be in line with the axis of

impact device.

·After every test, value display area will show the hardness and strength of

this test, at the same time, the number of test times will add one.

Tested value displays “E ” means that value exceeds the conversion

range and this test loses efficacy. The test times area displays without

any change. (Except for “E” which is got after converted)

(4) Check of the test result

Press the numeral key(the numeral should be no more than test times,

otherwise, the tester will have no response), the result of this test will be

displayed. The characters in the value area begin flashing and it is ready

for the result check. Press the keys “H/δ b”, “MATERIALS”, the data

conversion can be performed. If you want to delete the result that deviates

too much, press the key “AVERAGE/DELETE”. The following test

results will move forward and the total test times will reduce one. At this

time, the result check mode has been quitted. Press the key “LAMP” or

have a test and this will quit the check mode without any test results

deleted.

Note: If preset the test date and impact device under the check mode, the

check mode will be quitted too.

(5) Displaying the average value of one group of test values:

Generally, the measured value should be the average of 3～5 or even

more times of tests. However, the test times should be no more than 9,

otherwise, the former 9 test values can not be reserved.

Press the key “AVERAGE/DELETE” when it is not in the check mode,

the value display area will display the average of the hardness or strength

of this group tests and at the same time show the symbol “AVE”. After

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this, this group of test is finished.

Note: Whenever before the tester is shut off of after it is turned on, if

the average is displayed or the test times is 9, this group of test will be

over. The next test begins from the first position. If the average is not

displayed or the test times is less than 9, the next test follows the last one.

(6) Printing

Press the key “PRINT”, the printer will automatically print out every test

result and the average.

·Example1

DATE: 1999.12.20

MATERIALS: STEEL

DIRECTION:↓

=====================

NO. LD

1 815

2 811

3 809

AVE 812

Note: Test date: DEC 20,1999

Test material: Steel and cast steel

Test direction: Vertically down

Hardness: Leeb (type D impact device)

Test times: 3

Average: HLD=812

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·Example 2

DATE:1999.12.21

MATERIAL: STEEL

DIRECTION:↓

==================

NO. LD HB

1 398 138

2 210 ***

3 508 227

AVE 372 121

Note: 1) Test date: DEC 21,1999

Test material: Steel and cast steel

Test direction: Vertically down

Hardness: Leeb ( type D impact device)

2) “***” will be displayed when printing Brinell hardness at the

second time. It is because that the leeb hardness is chosen before test and

when the test is over, press the key “H/δ b” to select Brinell Hardness, for

the Leeb hardness value exceeds conversion range, the corresponding

Brinell hardness value will be displayed as “E” and printed out as “***”.

3) If the Brinell hardness is chosen directly before test and there is no

change in other parameters, the second test is shown as “E” and will be

deleted automatically. There is no the third test result when printing and

the second test is displayed as : LD:508;HB:227

4) If the Hardness is set as “Leeb”, it only prints Leeb hardness value.

If the other hardness and strength are set, it prints both the Leeb hardness

value and the converted value. Other hardness value, strength value and

average are all converted from the Leeb hardness value and its average.

5) Press any key corresponding to “test date”, test material and “test

20  

direction”, the head of the table will be reprinted next time.

Measurement of Steel and Cast Steel:

If the sample (or test block)is shaped by forging process and

the Brinell hardness

(F=30D∧2)is142 ～ 305(LD400 ～ 590),the errors of automatic

converting is greater. So the Hardness “Leeb” should be chosen.

Refer to the following table according to the average of HLD.

HLD-HB (F=30D∧2)

(8) Attached notes:

·During test, the illumination can be turned on or shut off at any time.

HLD 0 1 2 3 4 5 6 7 8 9

400 142 143 144 145 145 146 147 148 149 149

410 150 151 152 152 153 154 155 155 156 157

420 157 158 159 160 160 161 162 163 163 164

430 165 166 166 167 168 168 169 170 171 171

440 172 173 174 174 175 176 176 177 178 179

450 179 180 181 182 182 183 184 184 185 186

460 187 187 188 189 190 190 191 192 193 193

470 194 195 196 196 197 198 198 199 200 201

480 202 202 203 204 205 205 206 207 208 208

490 209 210 211 211 212 213 214 215 215 216

500 217 218 219 219 220 221 222 223 224 224

510 225 226 227 228 229 229 230 231 232 233

520 234 235 235 236 237 238 239 240 241 242

530 242 243 244 245 246 247 248 249 250 251

540 252 253 254 255 256 257 258 258 259 260

550 261 262 263 265 265 266 268 269 270 271

560 272 273 274 275 276 277 278 279 280 281

570 282 284 285 286 287 288 289 290 292 293

580 294 295 296 297 299 300 301 302 302 305

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However, the illuminating time should not be too long for its depleting

too much power.

·Test date can be changed at any time during the test.

·The set hardness, strength and test material can be changed at any time

during the test and then the test values of this group will be

automatically converted according to the new parameters.

·The set impact direction can be changed at any time during the test. The

test value before changement is still the same but the one after

changement is adjusted automatically according to the new direction.

·The test result can be printed out as many as wanted and also can be

printed out at any time according to the new parameters. Every time of

printing will print out the test values and their average of this

group of tests.

·The test result can be recorded after the tester is shut off.

3. Maintenance and Repair

(1) Maintenance

·Charge the tester termly. Generally, charge the tester for 10 hours every

8～24 hours′work.

·The impact device should be periodically cleaned and checked to see

whether the release button and positioning cap are loosen and whether

the impact body and the duct are dirty. When cleaning them, firstly

remove the supporting ring, secondly bring out the impact body, then

turn a brush into the bottom of the duct counterclockwise and bring it

out. After 5～6 time of brush, reassemble the impact body and the

supporting ring.

·Release the impact body after the test is over.

·Absolutely forbid injecting any lube into the impact device.

22  

·Replace print paper

Push the paper box cover outwards and remove it. After the print paper is

fit on, insert the end of the paper into the formfeed entry and press the key

“PAPER PEED”, replace the paper box cover after the end of the paper

moves out of the printer.

·Replace color bar

Remove the bolts from the tester, open the top cover and replace the

ribbon. After the ribbon is replaced, turn the knob according to the

indicating direction on the ribbon to tauten it.

·Replace battery

Open the battery cover on the back of the tester, there are four No.5

Ni-cd chargeable batteries inside. They usually can work for 3 years.

Open the cover and replace them after they are invalid.

·Check of hardness value

After every 1000～2000 measurements, the hardness tester should be

inspected for its accuracy. During inspecting, carry3 ～ 5tests on

standardized block and read off the HL values, then compare the average

HL value with the nominal value of the standardized test block. If the

measuring accuracy of the tester is within the range of allowable error,

than means the hardness tester is in normal state. If the measured values

exceeds the nominal value by±0.8%, the tester should not be used and

should be repaired.

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(2) Repair

The normal troubles can be checked and repaired according to the

following table. Please contact the manufacturer for other troubles′repair.

Trouble Cause Possible remedy

No display

display flashes

unable to charge

Battery potential is too

low

Make charge

Battery is damaged Replace battery

Fuse is broken Replace fuse

No value

displaying

Poor contact of impact

device

Clean and reassemble

Cable broken Reconnect

Too large

measuring error

Sample inadequately

prepared

Prepare sample over again

according to Section V.1(1)

Sample discrete value is

too large

Sample is not stably

supported

Support sample according to

Section V.1(3)

Wrong operation Operate according to Section

V.2(3)

The inside of the impact

device is too dirty

Clean the inside of the impact

device

Printer does not

Normally work

Shut off the tester immediately

and then restart after one

minute