I want to get the relationship between hertz and fpm.
Announcement
Collapse
No announcement yet.
How to convert Feet per Minute(FPM) to Hertz?
Collapse
X

Re: How to convert Feet per Minute(FPM) to Hertz?
The situation is in a wood plant where a tenonor has different gap spacing
for three lines. One line has 12" spacing another has 10" and the last has 8"
spacings. The feet per minute to hertz ratio or relationship I guess would
have to be based on the diameter of the sprocket to the motor speed which
is being driven by an inverter.
The current machine in question was setup to have 100fpm = 60hz. I want to know if this is just simply getting the relationship of 1hz = 1.67fpm? by
dividing 100 by 60. This machine has 8" spacings.
The other machine which has 10" spacing does not have a relationship like this since it was a machine that was modified in the plant.
Comment

Re: How to convert Feet per Minute(FPM) to Hertz?
Originally posted by Robert FogtHertz means one cycle per second.
I do not see a way to convert that directly to a unit of speed. You will need to describe your circumstances.
Robert,
Please refer to the #3 Reply. This was meant for you and not a reply to myself.
Thanks,
Rich
Comment

Re: How to convert Feet per Minute(FPM) to Hertz?
If you know the diameter of the sprocket that drives the wood, first calculate the circumference.
circumference = Pi * diameter
So a 10 inch diameter wheel will have a 31.4 inch circumference. And at 1 hertz (once per second) the wheel will move 31.4 inches/second.
31.4 inches/second * 60 = 1884 inches/minute
1884 inches/minute / 12 = 157 foot/minute
Comment

Re: How to convert Feet per Minute(FPM) to Hertz?
Originally posted by Robert FogtIf you know the diameter of the sprocket that drives the wood, first calculate the circumference.
circumference = Pi * diameter
So a 10 inch diameter wheel will have a 31.4 inch circumference. And at 1 hertz (once per second) the wheel will move 31.4 inches/second.
31.4 inches/second * 60 = 1884 inches/minute
1884 inches/minute / 12 = 157 foot/minute
We have the diameter of the sprocket but we also have a gearbox attached to the motor that has a ratio of 34.45 on the nameplate but no output number. This will change the FPM
Comment

Re: How to convert Feet per Minute(FPM) to Hertz?
The hertz will vary but nominally it is 60Hz. I just need the relationship between the two that also includes the gearbox. The hertz is variable by the use of an inverter to increase or decrease the speed of the chain. The motor is 1760RPM but the output is changed by the gearbox ratio of 34.45.
Comment

Re: How to convert Feet per Minute(FPM) to Hertz?
I agree with the post before this one...
There is not a direct relationship, but when comparnig HZ to FPM in a wind tunnel (or duct) you can use the formula:
velocity = sqrt((Pressure*2)/density)
This then can be compared to the HZ that the pressure was taken at... this would be experimental data.
Comment
Comment