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Beats Per Minute

jey_c ยท 2011-03-11 16:15

Any idea about how to measure hydraulic breaker BPM(Beats Per Minute), is there any specific technique?

Replies11
  1. #1Hendrik2011-03-11 18:47

    How fast can you count? Far as I know the only way to know is to look up the specifications of the breaker. However as a general rule, the bigger the breaker the less BPM, for example Krupp breakers have a range of 570-1700BPM for the small HM60 and 280-450BPM for the HM4000. However this does not mean a HM2300 will have BPM rate halfway between the 60 and 4000, it has a range of 280-540BPM. The reason for the range is that at idle the breaker will have less BPM than at full speed. www.hydrotecno.it/UserFile/File/Pali/MartelloIdraulico.pdf

  2. #2motrack2011-03-11 21:51

    We just adjust hyd flow to high side of breakers manf specs and give it a test. If there is a problem with the hammer you will hear it.

  3. #3Lee-online2011-03-11 22:27

    Flow them and check the nitrogen charge. NPK hammers are slow and heavy hitting but the Cats are fast and lighter hitting. Its just how they are designed.

  4. #4hvy 1ton2011-03-11 22:29

    Anybody ever use a chronograph to check the hammer speed?

  5. #5RonG2011-03-12 05:29

    I would be inclined to do an audio recording of it in operation,capture it in any computer and using a free program called "Audacity" you could possibly count the audio spikes by filtering if necessary and isolate the the impulses to determine the frequency of the strikes. If you recorded onto a laptop with Audacity installed on it it should be pretty simple. There are other free programs as well but Audacity is the one that I am used to so is my choice.I use it to measure the shutter speeds of cameras that I am working on. If you have an ocilloscope you can measure it that way.The reciprocal of time equals frequency but if you had a scope you would know that.Ron G

  6. #6wsw2011-03-12 18:50

    If flow and pressure is adjusted right, you should know if the breaker is working right. I have done some big breakers and you can almost count the beats on the larger ones, but I myself would be more interested in production P/hr than beats per minute. What particular breaker are you using and on what carrier

  7. #7Hendrik2011-03-12 19:22

    I reckon slow and heavy is better than fast and light, less wear on the breaker. Don't think you'd find too many breakers above 1 tonne that are fast. Obviously the smaller breakers need speed to be productive, as they don't have the weight behind them.

  8. #8jey_c2011-03-13 13:59

    I am using a furakawa breaker F35 on a P300-6 komatsu excavator

  9. #9heavylift2011-03-13 14:51

    we had one that was tap.......... tap......... tap... then a little dust... they called a mechanic. charged the nitrogen... then tap break tap break... no more making dust after they charged the cylinder..

  10. #10jey_c2011-03-13 16:23

    how can i do an audio recording, do i have to use a special microphone ?

  11. #11RonG2011-03-13 17:48

    No,just the normal built in mic on a laptop or any mic that will record an audio signal.You will be reading the wave form on your computer display using Audacity,the display will be amplitude modulated and the output will be similar to an oscilloscope display. The timebase of your soundcard which is what you are using to read the audio input is usually 48khz which is plenty fast for audio work.Ron G