The issue of screw joint vibration safety is of ongoing interest to product developers, production experts, industrial engineers, maintenance and safety officers. The reason for this is obvious: safety takes top priority. So don’t leave things to chance – put your products through an independent Junker vibration test in our laboratory.
Junker vibration test: when does a fastener come loose?
What is a Junker vibration test?
The Junker vibration test described in DIN 65151 allows us to compare different fasteners and their ability to maintain clamp load under extreme conditions in just 30 seconds. The test is carried out using a transverse dynamic load. The results provide the design engineer with information about joints design safety and how effective their selected fasteners really are. One exciting element of this type of test is finding out how long the preload force is maintained for, which elements the preload force drops for and how much by exactly. Sometimes, the preload force is lost completely, which can cause major problems.
When should a Junker vibration test be carried out?
Anywhere that joints are exposed to vibrations will put high demands on the fasteners. Typical examples include applications in railway and aviation technology, where joints are exposed to particularly high dynamic loads. In-component vibrations lead to micro-movements and cause screws to come loose by themselves if the fasteners are not secured correctly. This situation must be avoided at all costs. A Junker test will show you whether your screw fastener will really hold.
How the test process works
The DIN 65151 Junker test shows the loss of preload force relative to the duration of a dynamic load. For the test, the screw in question is mounted on a test rig and the clamped parts are subjected to a transverse dynamic load. A load cell is used to measure and record the preload force throughout the test while it is put under a constant transverse load. This not only enables testing of the particular fasteners, but also allows direct comparison with possible alternatives. Our short video shows how the test works in practice.
What are the benefits for customers?
The Junker test is used to determine which fasteners maintain clamp load when under the influence of vibration and which don’t. Having this information helps engineers to design safe joints with a long service life.
Bossard – your expert in Junker vibration tests
Access to accredited test laboratories with cutting-edge measuring techniques forms the basis for reliable quality assurance and high-quality products. Bossard has a number of selected test laboratories worldwide that are accredited according to ISO 17025 and as well as quality management systems registered to ISO 9001. Let our experienced Junker vibration test specialists support you with their extensive expertise.
Contact our experts to find out more about Bossard’s Expert Test Services. We look forward to hearing from you!
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