Portable hardness testers Bench hardness testers Automatic systems

ERNST is a company with over 50 years’ experience in the research, design and production of high quality metal hardness testers.
Active in the international market with an extensive range of metal hardness testers, it gathers information and requests from a demanding and diversified market, in order to continue to be at the forefront of the production of machines for controlling, measuring and testing materials.
ERNST patents are the story and the future of the company, a company that is constantly researching new technological solutions to the still unsolved problems in metal hardness testing.

The sales program of Ernst includes:

• Rockwell hardness testers

• Brinell hardness testers

• Vickers hardness testers

• Portable hardness testers

• Bench hardness testers

• Metal hardness testers

Among all kinds of inspections that are carried out in a workshop testing of hardness is the most diversified.
Testing can be made at 3000 kp (29430N) or with some hundreds grams; in laboratories, testing is made even with few grams.
It is possible to test the hardness of heavy castings as well as of pins for horology, from the hardest sintered materials to the softest alloys.
There are so many methods and hardness scales to be used that even those who have a considerable workshop experience can get confused when facing such problems.

Ernst manufactures and distributes different kinds of metal hardness testers, to meet the various testing requirements.

It is possible to move the work piece under the tester as well as the tester over the work piece. The first case concerns bench hardness testers, that allow holding and clamping of the part during testing; bench hardness testers are suitable for testing of small and medium parts.
The second case concerns portable hardness testers that can be clamped to the work piece or simply placed on large and irregular parts.

Testing on particularly difficult parts should be evaluated from time to time.

The range of bench hardness testers:

NR3 DR / NR3 DSR Rugged and easy-to-use Rockwell / Superficial Rockwell bench hardness testers, with standardized preload and load. Test loads for Brinell testing. Output RS232

AT130 DR / AT130 DSR Bench hardness testers for Rockwell / Superficial Rockwell testing. Standardized preload and test loads. Test loads for Brinell testing. Four different stands available. Output RS232

AT200 DR / AT200 DSR Bench hardness testers, similar to AT130, with digital readout through microprocessor.
Swift testing, data printing, statistics, tolerances, etc. Eight or more hardness scales available. Four test stands available. Test loads for Brinell testing.
Output RS 232 and CENTRONICS.

MTR Bench hardness tester ESATEST-series
ESATEST-series makes use of a new testing principle that allows testing of odd shaped parts, difficult test points, as grooves, holes, involutes.
With one test only, it is possible to display the hardness values at different loads. This is particularly helpful when testing of surface treated areas to learn immediately the case depth.
Test results are automatically shown on a LCD backlit display.
The electronics permits further different functions.
MTR is the motorized version of the ESATEST-series.
Output RS232 and CENTRONICS.

TWIN Bench hardness testers for testing of Rockwell and Superficial Rockwell hardness.
Test head displacement, load change and load application are automatic.
45 mm penetrator’s stroke
Insensitive to any deflection of the test piece.
Possibility of removing the elevating screw assembly for in-line applications.
The electronics permits further different functions.
Output CENTRONICS

BRE-AUT Automatic hardness tester for Brinell testing with variable loads from 500 to 3000 kp.
Suitable for custom in-line applications.
Output RS232 and CENTRONICS.

The range of Ernst portable hardness testers include:

COMPUTEST SC Portable hardness testers with direct reading of test results on LCD backlit display. Seven or more hardness scales available. Static testing on flat and cylindrical surfaces and on different metals.
Test load 5 kp. Output RS232.

DYNATEST SC Portable hardness tester similar to COMPUTEST SC, but with heavy load (more than 100 kp).
Four or more hardness scales available.
Unique of its kind, this portable tester allows the accuracy of a bench hardness tester thanks to the heavy load.
Ouput RS232.

HANDY Portable hardness testers ESATEST-series
Portable execution of the MTR model. Weight of the instrument 1.5 kg
Output RS232.

STE A / STE B Dynamic or static-dynamic portable hardness testers working with calibrated pins. Test load 1580 kp. Test results in Brinell scale and tensile strength. In compliance with the Brinell 30 D² standards.
 

Metal hardness testers

Almost all ERNST hardness testers are particularly suitable for testing metals, giving the operator the possibility to choose the right hardness scale and the test load according to the test material.

The following table can be a valid aid to choose the most suitable hardness testers for your purposes:
 

Rockwell hardness testers

The Rockwell hardness test can be divided into two groups: Rockwell and Superficial Rockwell.
The difference is given by the test loads, which for the Rockwell test are heavier than for the Superficial Rockwell test.

The ERNST Rockwell hardness testers are designed to take the advantages from the Rockwell test, such as the employ of diamond indenters for testing tempered steel or hard metals, and the ball penetrators for soft metals. The Rockwell method allows testing of plastic even under load.

The ERNST Rockwell hardness testers allow overcoming some limitations of the Rockwell method.
The main disadvantage of the traditional Rockwell hardness testers is that the accuracy of testing depends to a large degree on the perfect contact between the work piece and its support, usually called the anvil.
In the presence of oil coat, some grease or other between the test part and the anvil, a little movement occurs during load application, when added to the indentation depth, gives a wrong result, decreasing the hardness value.
Because it is not always possible to work in perfect conditions, for example in heat treatment or workshop environments, this is an important consideration.

To overcome this problem, almost our hardness testers (AT-series, TWIN, BRE-AUT, COMPUTEST SC, DYNATEST SC) work according to a modification to the Rockwell principle.
In this case, a support on the test surface gives the penetration depth. Therefore, any movement of the part, elevating screw or stand, does not influence the test result.
Thanks to this method, the same advantages of the Brinell and Vickers principle are reached.

The ERNST bench hardness testers have a third important component, called clamping shield.
The clamping shield is used for locking of the test piece, avoiding the use of any special support; the clamping shield can be easily removed if needed.
In portable hardness testers, this component is called base, it is interchangeable and helps creating a perfect support on the test piece.
 

Brinell hardness testers

I Brinell hardness testers allow employing heavy loads in quite simple and rugged structures
The indentation diameter is read with an optical system (eyepiece or microscope).
Testing is possible even if positioning of the piece is not perfect, because the Brinell test is not sensitive to deflection of the test piece.
It is possible to derive the tensile strength value simply by multiplying the Brinell hardness number by a certain factor, changing according to the test material.
In spite of the heavy load, an accurate surface preparation is needed to obtain reliable results.
For this reason, the Brinell test cannot be considered a quick test and it is not suitable for testing of high volumes.
To overcome this problem, Ernst has designed a series of Brinell hardness testers operating according to Rockwell method, but using Brinell penetrators and loads.
In this case, the difference of penetration between preload and load gives the indentation measure.
Test results are directly shown on the display or on the dial indicator in Rockwell numbers that will be converted in Brinell numbers using the proper table.
This method is more convenient in the case of high volume testing, as it allows avoiding the optical reading and the surface preparation required by the classic Brinell hardness testers.
To increase the accuracy in the case of high volume testing, the range of Ernst Brinell hardness testers give the operator the possibility to introduce a new and temporary calibration of the Brinell scale, based on Brinell test blocks, where the indentation has been made by classic Brinell testers.

Vickers hardness testers

The working principle of Vickers hardness testers is the same as the Brinell one, but in this case it employs only one indenter, being a pyramidal diamond with square base.
After the indentation is made, the two diagonals will be measured and as these are almost never the same, the average value will be considered.
As per the Brinell hardness number, the Vickers number is given by the relationship between the applied load and the surface area of the indentation.
There are different test loads, but the most common used are: 1, 2, 5, 10, 30kp (9.81, 19.62, 49.05, 98.10, 294.30).
It is possible to work with Vickers hardness testers employing loads lighter than 1 kp (9.81 N) entering in this way the micro-indentation hardness field, whose main application takes place in metallographic laboratories.
Even in the presence of layers, Vickers hardness testers can be conveniently employed, using increasing loads to determine the case depth.
As for Brinell hardness testers, Vickers hardness testers are not sensitive to any deflection of the work piece.
The limitation of the Vickers method is due to the low speed of operation, as the measurement of indentation has to be made optically (microscope or profile projector) or employing computer automatic systems for indentation reading distributed by ERNST.
The test area must be carefully prepared and polished. For this reason, perpendicularity of the indenter axis is a very important factor, as any inclination would give an irregular indentation.
For these reasons, Vickers method is not recommended for testing in production lines.
To overcome these disadvantages, we have designed a new series of hardness testers to read the Vickers hardness in a rapid and easy way.
These testers make use of our patented ESATEST technology based on the measurement of electrical resistivity.

Some of our hardness testers:

DYNATEST SC Heavy load portable hardness tester Testing load more than 100 k p (98 N) Digital readout in Rockwell and Brinell hardness scales (Vickers and other scales on request) Print functions in 5 languages, statistics, 1000 tests can be stored, RS232 output, backlit display. Performances comparable to a bench tester.

HANDY ESATEST Portable hardness tester Digital readout in Vickers hardness scale (other scales on request) A new concept of hardness tester for testing of odd shaped parts and difficult test points. Possibility of testing flat and cylindrical surfaces, gear evolvents, etc.

COMPUTEST SC Light load portable hardness tester (5 kp). Digital readout in Rockwell, Brinell and Vickers hardness scales (other scales on request). Optional bench stand for testing of small parts. Magnetic support and other equipment available. Print functions in 5 languages statistics, 1000 tests can be stored, RS232 output, backlit display.

STE Ernst Calibrated Pins Tester Portable hardness tester for Brinell testing. Testing load 1580 kp Precise – easy to use – reading of one impression only

NR3 Digital hardness tester, based on the Rockwell test principle with instantaneous readout in Rockwell and Brinell scales (other scales on request). Suitable for testing of small parts and plastic materials.

AT130 Semi-automatic bench hardness tester, based on Rockwell test principle with instantaneous readout in Rockwell and Brinell scales (other scales on request). Overhanging parts can be clamped without any extra support. Four different stands are available for testing large parts. Testing is not influenced by flexions or bending of the work piece.

AT200 Semi-automatic bench hardness tester, digital readout in Rockwell hardness scale and in equivalent Brinell, Vickers and other hardness scales. Sequential application of preload and load. Storing of 4000 hardness values in 64 different files, printing of the test certificate in 5 languages, display of statistics and histogram. Large LCD backlit display, 107x57mm Clamping of overhanging parts without any extra support. Four different stands are available for testing large and irregular parts.

ESATEST MTR A new concept of hardness tester for testing of odd shaped parts and difficult test points, as grooves, holes, involutes, etc. Digital readout in Vickers hardness scale (other scales on request). Motorized test load application. With one test only, it is possible to display the hardness value at different loads from 9.8 to 98 n (1-10 kp) and to notice any anomaly or non-homogeneity of the material. The 16bit microprocessor system allows handling of more than 4000 hardness values.

TWIN Automatic hardness tester motorized. Digital readout in Rockwell and superficial Rockwell scales and in equivalent Brinell, Vickers and other scales. Indenter’s stroke 45mm Max measurable height 420mm Automatic load change Large memory, up to 4000 values can be stored in 64 different files Printing of test certificate in 5 languages, display of statistics and histogram, Centronics and PC output. Unaffected by any deflection of the test piece. Possibility of testing very large and irregular specimens.

AT300 DR-TM AT300 DR-TM is a motorized hardness tester, particularly suitable for high volume testing (approx 1000 pcs/hour), custom in line applications for a completely automatic test process and test part selection. The possibility to motorize also the test head motion permits a considerable reducing of the test time. A very versatile stand permits testing of large parts. The basement of the stand contains a convenient accessory drawer.

BRE-AUT Automatic Brinell hardness tester Test time reduced by 85% in comparison with the traditional Brinell testers. Adapted for completely automatic in-line operation. The 16-bit microprocessor of the electronic console has been designed to guarantee full documentation of the test process, providing a wide range of functions such as: adjustable tolerances, calibration, serialization of readings and lot number, print, statistics, graph, etc. The test certificate can be printed in different languages.