METHOD OF DIAGNOSTICS OF TURBOMACHINE TRANSMISSION BEARINGS AND DEVICE INTENDED FOR ITS REALIZATION Russian patent published in 1998 - IPC

FIELD: diagnostics of turbomachines. SUBSTANCE: in "Training" mode, vibration pickup is positioned on mechanical oscillating element. The latter is installed in motor, and range of motor shaft rotational frequency from f_min to f_max is determined when motor shaft rotates within f frequency range from Δf to (Δf≤f_min), with motor rotational frequency varying in steps of f₁ which is less than or equal to minimum frequency f₂ of motor shaft rotation. Rigidity and coordinates of reference points of mechanical oscillating element are also determined. At these points difference of any two amplitudes A_i,A_k of vibration pickup oscillations ΔA for "standard" bearing is considerably less than minimum amplitude of vibration pickup oscillations (ΔA = A_i-A_k≪ A_min for given "standard" bearing. Oscillation amplitude of vibration pickup for given "standard" bearing is taken for maximum permissible amplitude A_m.p.. In diagnostics mode vibration pickup is placed on mechanical oscillating element with rigidity and coordinates of reference points determined in "Training" mode. Mechanical oscillating element is installed in motor with bearing under test, motor shaft is rotated at frequency f being within the range of f₁ to f₂, and vibration pickup oscillation amplitude is measured. If amplitude is below maximum permissible oscillation amplitude A_m.p. of vibration pickup, bearing is fit for further operation. If oscillation amplitude exceeds maximum permissible oscillation amplitude A_m.p. of vibration pickup or is equal to it, bearing under test must be rejected. Device intended for method realization has series-connected vibration pickup, amplifier and indicator. It is provided with n(n≥1) mechanical oscillating elements. Every mechanical oscillating element carries vibration pickup, first feedback resistor, n second feedback resistors, decoder with n outputs and m(m≥1) inputs. Vibration pickups are provided with permanent storages, m outputs of which are connected to decoder inputs. Decoder outputs are connected to first leads of second feedback resistors, the second lead of which are combined and connected to first lead of first feedback resistor and to second input of amplifier, the output of which is connected to second lead of first feedback resistor. EFFECT: more reliable diagnostics.