Compression tests is another test that will help us to perform a successful quality control of the material in question, determining its resistance to compressive stress or load.
This practice is used concrete or cement, rubbers, rocks, woods, plastics, composites, etc. e incluso para valorar el aguante de piezas acabadas.
They evaluate the safety, durability and integrity of materials and components.
How are compression tests performed?
In order to carry out the test, a test tube of the material to be tested on a specific test rig. The test is performed in such a way that the procedure specification is met and the necessary data is collected on the press gauges.
Compression test data provide results in the form of a stress-strain diagram that, among other things, show the following;
- The creep limit, the point at which the material enters the state of yield, causing irreversible deformation of the specimen.
- The single resistance limit or breaking strength limit, which represents the maximum stress a material can withstand before breaking.
- The breaking point, which indicates the exact stress at which the material breaks.
At Servosis we have the necessary machinery to carry out this type of material compression tests. Among our catalog for compression testing machines we find the SERIE MES.
Compression testing machines
SERIE MES
The Series MES are for testing specimens of concrete, rock, cement and other materials. of construction between 150 and 800t. This type of machine are built according to ENE standards -EN 12390-4 WITH PRECISION Class 1 according to UNE-7500-1.
These machines can be equipped with single-acting or double-acting actuator.
In the first case, it is controlled with a proportional valvesufficient for simple compression tests.
In the second, is controlled by a servo valve and incorporates a displacement reader and double pressure sensor. This system provides the machine with high pressure control, which is necessary for certain types of tests.
It is also possible to close the control loop by force or position, in this way MES series machines equipped with double-acting cylinder are an improved alternative to traditional compression testing presses.
All machines of the MES series are prepared for the connection of an additional testing frame, normally for bending tests on prismatic specimens. Both the hydraulics and the control system are prepared as standard for the incorporation of this second compression test frame.
A specific application for the MES Series is the performance of tests on rocks, for which we need various accessories:
-Hoek cellfor triaxial test according to UNE 22- 950-92
-Strain gage measurement module, Direct module for direct measurement with strain gages for Poisson coefficient calculation glued on the specimen. Standard 4 channels expandable to 8.
-Measurement module with deflectometer, for axial deformation measurement and modulus calculation.
ANALOG MEASUREMENT MODULES
Measurement with strain gages
Strain gages directly glued on the specimen are used to measure the axial and diametrical deformations that occur in the specimen during the triaxial test.
Usually the test is performed using 4 bands. 2 of them for axial deformation measurement and 2 for diametral deformation.
The compression testing presses of the MES series can incorporate measuring systems with belts to perform these tests, from the measurement obtained. the Poisson's coefficient is obtained.
This equipment is equipped with a wheatstone bridge signal conditioner. The measurement of the different bands is connected to a previous step that completes the wheatstone bridge and the measurement of this one to the conditioner.
ANALOG MEASUREMENT MODULES
Measurement with deflectometers
When the test does not require the use of strain gagesIn order to have a direct measurement of the deformations that occur in the specimen, an option to have a direct measurement of the deformations that occur in the specimen is the use of deflectometers.
Mounted on specific supports or in contact with the compression plates of the press, these devices offer a direct deformation measurement for the calculation of modulus, axial deformations, etc....
La MES series , Servosis testing machines can incorporate analog measurement modules for use with deflectometers or any other type of extensometry element.
MES series. Control Software
The machine is controlled through the PCD2K software, where the user has different possibilities for its use:
The options for general use, with which the maximum performance possibilities are available in the performance of compression tests. The customer can configure his test in a customized way and process the data afterwards.
Customized windows for compression tests under Standard, which provide maximum simplification in the performance of a specific test, since only the elements necessary for the performance of this specific test are included in a single window, and the results of all the calculations indicated in the standard are obtained directly. These windows are always designed according to the needs of the test and the customer's request.
The same machine can be loaded as many times as many times as many times as many times as many times as many times as many times as many times as many Test standards as desired with no other limitation than the maximum load capacity imposed by the machine and the maximum speed, determined by the hydraulic unit.
In the test report the Standard will appear under which the test was performed, the test parameterization, the machine data and the test results, in addition to the Graph curve Force/Deformation.
At Servosiswe have all the necessary equipment to perform both compression and non-compression tests.
If you want more information about our compression tests get in touch with us!
