Bearing functions
Functions related to i.e. bearing lifetime and geometry
- pyvib.bearing.bearingcharfrequencies(D, d, n, theta=0.0)
Calculate bearing characteristic orders from dimensions. Equations taken from: Rolling element bearing diagnostics-A tutorial by R Randall and J Antoni
- Parameters
- Dfloat
Pitch diameter
- dfloat
roller diameter
- nint
Number of rollers
- thetafloat, optional
Contact angle in degrees
- Returns
- bearingarray_like
Bearing fault orders (inner, roller, cage, outer)
- class pyvib.bearing.bearinglifetimemodel(L10)
Makes a Weibull lifetime distribution for a bearing
- Parameters
- L10float
Lifetime of bearing in million revolutions
- .. method:: life:
Get lifetime in million revs based on probability of survival
- .. method:: survival:
Get survival probability based on number of revs
- returns
bearing (class object)
Bearing object
Methods
life(S)Get lifetime in million revs based on probability of survival
survival(L)Get survival probability based on number of revs
- life(S)
Get lifetime in million revs based on probability of survival
- Parameters
S (float) – Probability of survival. <0.0, 1.0>
- Returns
L – Lifetime in million revolutions
- Return type
float
- survival(L)
Get survival probability based on number of revs
- Parameters
L (float) – Lifetime in million revs
- Returns
S – Survival probability <0.0, 1.0>
- Return type
float
- pyvib.bearing.bearingsimulation(t, s, fo, beta=1000.0, omr=10400.0, taustd=0.02, initpause=0.0, amp=1.0, debug=False, seed=None)
Make a simulation of a bearing with an outer race fault
- Parameters
- tfloat 1D array
Time signal
- sfloat 1D array
Shaft angle position in number of rounds
- fofloat
Outer race fault frequency
- betafloat, optional
The damping ratio
- omrfloat, optional
Resonance frequency in Hz
- taustdfloat, optional
Standard deviation change in percentage between each impact
- initpausefloat, optional
Initial pause in rounds before first impact
- ampfloat or function, optional
The impact amplitude vibration: - If float, the same amplitude all the time - If function, the instantaneous velocity is used as input and
the amplitude is returned
- debugboolean, optional
Whether debug information is returned If true, the percentage finished is printed
- seedint or None, optional
Choose a seed number for numpy, must be positive.
- Returns
- xfloat 1D array
The bearing vibration
- pyvib.bearing.bearingsimulation_ahc(t, s, fo, amp, beta=1000.0, omr=3543.0, initpause=0.5)
Make a simulation of a bearing with an outer race fault where the shaft speed can pass 0 rpm speed.
- Parameters
- tfloat 1D array
Time signal
- sfloat 1D array
Shaft angle position in number of rounds
- fofloat
Outer race fault frequency
- ampfunction(v)
Amplitude function with shaft velocity as input. Must return scalar amplitude only
- betafloat, optional
The damping ratio
- omrfloat, optional
Resonance frequency in Hz
- initpausefloat, optional
Initial pause in fault-periods before first impact
- Returns
- xfloat 1D array
The bearing vibration