Demattia Flex Cracking Tester
Rubber Testing Equipment
Standards
Description
GenFlex tests whether a rubber product can be bent over and over without cracking. That matters wherever the part spends its working life in motion - a sole, a hose wall, a boot upper - because a compound that holds up in a tensile test can still split once it is flexed a few hundred thousand times.
The tester reproduces that flexing in the laboratory under fixed conditions of speed, mode and degree of bend, so results from one run can be compared with the next. The specimen is fixed into the movable grips and watched for the first crack; an intelligent failure system stops the run when the specimen gives way.
The tester flexing a specimen through its stroke.
A second recording of the same tester.
Models and Specifications
Two models cover two specimen shapes. GenFlex-B1 takes a long strip and runs a longer stroke; GenFlex-B2 takes a wider piece, moves it a shorter distance and cycles faster.
| Item | GenFlex-B1 | GenFlex-B2 |
|---|---|---|
| Specimen | 154 × 25 ±1 × 6.3 ±0.15 mm | 108 ±0.5 × 70 ±0.5 mm |
| Reciprocating stroke | 57 mm | 44 mm |
| Maximum distance between fixtures | 75 mm | 57 mm |
| Testing speed | 300 ±10 cpm | 340 to 400 ±10 cpm |
| Counter | LCD 0 to 999,999 | LCD 0 to 999,999 |
| Dimensions (W × D × H) | 13.8 × 23.6 × 29.5″ (35 × 60 × 75 cm) | 13.8 × 23.6 × 29.5″ (35 × 60 × 75 cm) |
| Weight | 172 lbs (78 kg) | 172 lbs (78 kg) |
| Power | 110 V / 60 Hz or 220 V / 50 Hz | 110 V / 60 Hz or 220 V / 50 Hz |
Have Questions or Need to Confirm a Detail?
Tell us the specimen you flex and the count you need to reach, and we will confirm which model to quote. A quick request online is enough to start.
For Laboratories
Need Additional Quality Control Equipment to Build Your Laboratory?
Flex cracking testing is only one part of a complete quality control laboratory. NextGen can help you equip your entire lab with rheometers and viscometers, abrasion and flex testers, ageing and salt spray chambers, hardness and rebound testers, specimen cutting presses, and other supporting solutions, all coordinated as one complete project.
- One partner to equip your complete laboratory
- Installation, training, calibration
- Support for the life of the equipment
FAQs
The following industry standards are typically followed when testing with the DeMattia Flex Cracking tester:
ISO 132, ISO 6943, ASTM D813, ASTM D430-B and JIS K_6260
Most commonly, rubber sole material is used in a DeMattia Flex tester. Due to the fact that the rubber soles are being used daily and coming into contact with roads, dirt and other elements, they endure the maximum level of flexing. It is the friction from all the flexing that can lead to a surface crack which can lead to failure of the rubber compound.
While rubber has an extremely high strength rating, it also exhibits some faulty characteristics after being exposed to heat, cold weather and humidity/temperature changes. After being exposed to these elements, it is common for a crack to develop on the surface and these cracks have a tendency to continue to grow. DeMattia Flex Cracking can help to estimate the rubbers lifespan after a crack has formed in the materials surface.
Up to 6 specimens can be tested at one time after setting the frequency per your industry standard.
The specimen must first be created in the size required per the industry standard. NextGen can supply the ASTM D430, Method B cutting dies along with the D813 mold required to perform these tests. ISO moulds can also be provided as a custom order.
The DeMattia test allows the operators to analyze the fatigue-cracking properties of the material in question. It provides a picture of the potential lifespan of the material when being used in its service application.
The DeMattia Flex Tester provides a representation of the ability for a punctured rubber specimen to resist crack growth while enduring bending and flexing. Because of the large number of variables, there is no exact correlation to draw between the test results and the ability of the rubber to perform in its intended application.
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