Specimen grinding / finishing machine

for blanked / laser cut / milled sheet metal tensile specimens

The fundamental requirement to receive correct results of sheet metal tensile testing is the specimen itself – correct dimensions, finished surface at the edges and correct preparation in general without influencing if mechanical properties of the tensile specimen.

Punching / blanking is the most effective and economical method of sample production if there is the possibility  to remove in fast and effective way the work-hardened zone / damage of edge of the specimen. The sheet metal tensile specimen PSM 2000 (well known since 1970) was re-designed to meet this requirement in a perfect and fast way. The use of the machine is as easy so also an unskilled worker is able to prepare high quality specimens after several minutes of training. The specimens will receive perfect parallelism in gage length (within parallelism of 0.02 mm). The grinding process takes less than 2 or 3 minutes (depending on the kind of specimens). The quality meets and accede the requirements of all testing norms and IDDRG international deep drawing research group.

The machine is under continuous improvement process and actually we are building the fifth generation. At this the grinding belt will receive the tension by a pneumatic system. This increases the comfort and also the reliability of parallelism of grinding.

PSM2000 the synonym for highest quality in sheet metal tensile specimen preparation

Suitable for blanked specimens and also specimen cut be laser, water jet, milling and others…

The machine is contents an industrial level of quality with a grinding belt of 2000 mm length. The grinding speed of the belt meets the required speed for grinding process on metal (30 m per second) and has an big surface of the grinding consumables (surface 2’000 mm in length x 100 mm in width = 200.000 mm²). For special requirements we are able to deliver special grinding belt with cooling function ore for special materials like titanium, stainless steel, carbon steel and more. Some of our customers are using also aluminium oxyd grinding paper to use this machine also for specimen grinding for spectral analyses (not to contaminate the metal with carbon from SiC-paper).

Sheet metal tensile specimen - shapes according the different standards

Die Probenschleifmaschine kann für alle unten gezeigten Zugproben ausgelegt werden

Identifier

ISO6892 B1-1
DIN 50125
shape 1
A50

ISO6892 B1-2
DIN 50125
shape 2
A80

ISO6892 B1-3

shape 3
(similar JIS)

Press hardening
special
(close to ISO)
A30

ASTM E8/E8M

shape
type 12,5

ASTM E8/E8M

shape

type subsize

JIS

shape
Z2241

GOST

GOST
sub

ISO

ASTM

Lt

L

200

250

200

~136

200 (min.)

100
(min. - <200)

200

 

151.2

B

C

20

30

35

9

20

10

35

 

20

h

B

~50

~50

~55

45 (min.~45)

>50 min
(shall cover
2/3 of grips)

>30
(shall cover
2/3 of grips)

~55

 

~40

R

R

20

20

25

15

20 (min.12.5)

15 (min.6)

25

 

15 (min.6)

Lc

A

75 (min.57)

120 (min.90)

60 (min.)

36

75 (min. 57)

36 (min.32)

60

 

36

L0

G

50

80

50

30

50 +1

25 +1

50

 

 

b0

W

12.5 +1

20 +1

25 +1

5

12.5+0,2

+ 0..1

25

 

12.5

aT    < 19< 6   

Lc paralism

0.06

0.12

0.12

0.06

0.05

0.02

0,1

 

 

b+

punch with oversize to remove damaged edge / cold hardened zone by grinding

 

Video

Contour grinding with high quality - Illustration of working principle

sheet metal tensile specimen is positioned (for demonstration) on the grinding belt. The grinding belt respectively the grinding head with pulley rollers are shaped like the tensile specimen (including the radius). Within on two minutes (including specimen loading) the damaged / cold hardened zone from punching will be removed by finishing with grinding paper. All influencing deformations and failure of specimen (like cold hardened zone from blanking, micro cracks, material compression, material deforming) will be removed completely.

These abrasive technology generates no heat. Because of the low temperatures (up to about 60 degrees C) the material characteristics are not influenced. To change the mechanical properties of the specimens a temperature of >120 degrees are required – fare away what grinding process will bring up.

 

For different specimen shapes different grinding heads (with different distances of pulley rollers) and different specimen holders are available. The exchange of this heads is possible in less than 2 minutes. Because of very special design now we are able to support also specimens with Lc of only 36 mm/ L0 of 30 mm (at radius 15 mm) can be finished.

Typical specimens shapes: A80 / A50 / ASTM A370 / JIS / A30

Grinding head with grinding belt rollers is designed exact according specimen shape (reduced section including radius)

The finishing process for a specimen for a sample batch (up to 15 mm) for:

  • specimen loading
  • grinding both sides
  • take off the specimens

takes only 2 minutes

The specimen quality is higher than every other method for finishing sheet metal tensile specimens. Valid is also the statement of industry: If r+n values are required the specimen grinding machine can’t be missed indispensable.

Because from sheet metal plate to „ready to test“ tensile specimen takes only three minutes (including blanking the specimen this is just THE system suitable for low and medium throughput within a short time.

... even if the loaded truck with coils is waiting to receive the final acceptance / release of tensile test.

The specimen grinding machine PSM 2000 is one of the most recognized principles in the field of sample preparation for tensile tests on sheet metal. In some particularly sensitive to reactive materials is the only adequate system to remove the damaged edges - because even a high precision CNC milling machine will change the properties of this sensitive material.

More and more, this machine is also required for the tensile test specimens of particularly hardened specimens with low elongation (Keywords: hot forming, hot forming dies, hot stamping, press hardening, machining of hardened tailored blanks).

Thus, with this grinding process, also samples with tensile strength of 1’600 MPa or higher can be finished.

The specimen grinding PSM2000 is now used for solving this particular problem of high-strength sheet / hot stamping tensile specimens from the following companies:

Customer

State

ZIP Town

VOLKSWAGEN AG

DE

38436 Wolfsburg

VOLKSWAGEN AG

DE

38436 Wolfsburg

VOLKSWAGEN AG

DE

38436 Wolfsburg

VOLKSWAGEN AG

DE

38436 Wolfsburg

BRAUN-CarTec GmbH

DE

66773 Schwalbach

MAGNA IHV GmbH

DE

73441 Bopfingen

Magna International Stanztechnik GmbH

DE

37308 Heiligenstadt

BENTELER Automotive Rumburk s.r.o

CZ

408 01 Rumburk

Mubea Transmission

DE

58586 Weitefeld

voestalpine Polynorm GmbH & Co. KG

DE

73529 Schwäb Gmünd

Benteler Automotive SK s.r.o.

SK

901 01 Malaky

voestalpine Stamptec GmbH

DE

04626 Schmölln

Cosma Engineering Europe AG

DE

02722 Weikersdorf

HQM induserv GmbH (third party lab)

DE

08058 Zwickau

Gestamp Griwe Hot Stamping GmbH

DE

37339 Haynrode

GEDIA Gebrüder Dingerkus GmbH

DE

57439 Attendorn

Voestalpine Automotive Body Parts Inc.

US

WHITE GA 30184

TWB Company, L.L.C.

US

MI 48162 Monroe (Michigan)

Benteler Automotive SK s.r.o.

CZ

463 31 Chrastava

Ford Werke Saarlouis

DE

66740 Saarlouis

Benteler ?R, s.r.o.

CZ

438 01 Žatec

LINDE + WIEMANN Stanztechnik GmbH

DE

01920 Elstra

… further companies …

 

 

Indispensable this grinder will be if the specimens are hot deformed and cured in the mold: The samples can be machined only by such as lasers or wire EDM. Afterwards, however, the edge of the thermal influence (laser, etc.) must be freed.

When it comes to quality of the sample preparation grinding is essential for critical materials. So this machine is at almost all manufacturers of car seat safety systems related components: seat rails:

  • CRH Solingen
  • CRH USA - Alabama
  • BROSE Coburg
  • BROSE CANADA
  • BROSE Tschechien
  • FAURECIA Stadthagen

As simple the technique – as unbeatable the application and resluts. Also because unskilled workers may prepare high quality specimens.

You are using an extensometer to measure the elongation until rupture? The specimen grinding machine also is suitbale to solve your problems of rupture the tensile specimen outside of measuring knives: If required we can do a special reduction of grinding desk: This will cause a sidecut of your specimens 0.04 each side. Finally your specimens will brake just in the middle of the receive correct results in elongation.

Tensile specimen blanking machines, punching tools and specimen grinding machine are available for forces of 10 – 7'500 kN and for standards according ISO / DIN / EN, ASTM, BS, Afnor, Jis, Ghost, etc. This systems are suitable for sheet metal specimen preparation for thicknesses from 0.03 up to 13 mm.