The vibration test of the vibration table is divided into sine and random vibration. Because of the different physical processes, there is no strict equivalent relationship between the two. So, when choosing the test mode, no sine to random severity grade conversion. Next, let's show you what's the sine vibration:
Sinusoidal vibration tests use a sinusoidal signal with fixed or varying frequencies and amplitudes. At each moment, only one frequency is applied, and the test conditions include frequency range or fixed frequency, amplitude, and test duration.
Sine vibration in real environment seldom occurs independently of a single frequency vibration. This is true even when measuring acceleration directly on rotating machinery. Such as gears and bearings, the actual tolerances and gaps usually cause slight variations in frequency. The random characteristics of rotating machinery will also have some form of random vibration.
Sinusoidal vibration can be described as deterministic motion. Following the established law, it is possible to determine the state of any specified time in the future from the past state. In the process of sine sweep test, the modification method is usually used to determine the time of failure, because the failure is very likely to be closely related to the specific frequency, and the effect of the random vibration test method is not very obvious.
Of course, the sine test method usually takes longer time to excite the failure than the random test method, because it only takes a short time at each resonance point during each sweep.
Although only one frequency is applied at any time, if the sweep rate is slow enough, the specific formant of the sample can be maximized. It can also be used to detect potential destructive resonance points, especially in design and development experiments.
Another use of the sinusoidal vibration test is the resident test at the following frequencies:
A, the known forced frequency;
B, the resonant frequency of the sample
The above is the sine vibration test method, if you still do not know, welcome to inquire, we will serve you wholeheartedly.