Multi functional rotor and shaft test bench system

The multifunctional rotor test bench can perform general vibration measurement of rotating machinery; Start stop test, vibration measurement of rotor over critical speed（BODE diagram); The influence of rotor structure form (one span, two spans, two spans, and the number of counterweight disks) on critical speed; soft(scratch)The vibration mode of the rotor; Sliding bearing oil filmeddyOil film oscillation of sliding bearings; Sliding bearing collisionRubbing testNon contact measurement of radial vibration and axial displacement of the shaft; Sliding bearing axis trajectory; Vibration measurement of bearing seat and platform body; Attempt to perform dynamic balancing of single-sided, double-sided, and multi sided rotors, in total11 types of experiments.

For vibration testing of multifunctional rotor test benches, three methods can be used for measurement: acceleration sensors, velocity sensors, or displacement sensors. Install acceleration and velocity sensorsInstalled on the bearing seat of the test bench. If it is an acceleration sensor, directly connect the output of the sensor to the corresponding channel of the collectorICP port; If it is a speed sensor, directly connect the output of the sensor to the voltage signal input port of the corresponding channel of the collector. The collector collects vibration signals and inputs them into the computer, observes and records the waveform and spectrum of the vibration signals obtained, and compares the characteristics of the vibration signals measured by the acceleration sensor and the velocity sensor. Observe the changes in vibration signal and frequency spectrum after changing the speed of the rotor test bench.

Axis trajectoryWhen the rotor is runningaxisofpositionInstall two eddy current displacement sensor probes onto the sensor bracket in the middle of the experimental platform, forming a mutual connection90 degrees and adjust the distance between the two probes and the spindle. At this point, after the rotor test bench is started, the two sensors measure its instantaneous displacement in two vertical directions (X, Y), which is synthesized into a Lissajous diagram, and the key phase positions are marked on the Lissajous diagram. Each rotation corresponds to a rotor axis motion trajectory and a key phase mark. If two key phase marks appear, it indicates that an oil film has appeared on the sliding bearingeddyAt the same time, half speed vibration appears in the spectrum.

Rigid rotor dynamic balancing and flexible(scratch)There is a fundamental difference in the dynamic balance of a rotor. When the rotor operates below the first critical speed, it can be considered a rigid rotor; When the rotor operates above the first critical speed, it is considered to be flexible(scratch)Sexual rotor. The dynamic balancing of rigid rotors is usually carried out using the principle of single-sided weighted ternary drawing method, which is completed by a computer.

During the experiment, select a position on the counterweight plate of the rotor test bench (such as the position where reflective paper is attached) as the initial position, and then use the screws in the attachment of the rotor test bench as an unbalanced weight to add to the counterweight plate. Then measure and estimate according to the above method to obtain the unbalanced weight and position.

Start stop test, vibration measurement of rotor over critical speed（BODE diagram can be used to test several lateral vibration frequencies that affect the operation of the machine within the entire working speed range, their changes in the precession direction of the sliding bearing, and to decompose whether there is a motion mechanical fault or a machine structural fault, thereby quickly identifying the fault location.

（2） Structural composition

The multifunctional rotor test bench consists of:1 base, 2 main shafts, 3 counterweight plates, 4 speed regulating DC motors, 5 main shaft supports, 6 oil containing bearings and cups, 7 motor supports, 8 couplings, 9 eddy current sensor brackets, and 10 speed sensor brackets, as shown in Figure 1.

（3） Experimental content

According to the purpose of the experiment, the test bench can be assembled into several different types (one span, two spans, three spans, and several counterweight disks). Verify vibrations caused by quality imbalance, etc; Verify the theory of oil film oscillation; Verify free rotor disturbance. Combined with the software platform, the following experiments can be conducted:

1) General vibration measurement of rotating machinery;

2) Start stop test, rotor over critical vibration measurement (BODE diagram);

3) The influence of rotor structure form (one span, two spans, and several counterweight disks) on critical speed;

4) , Soft(scratch)The vibration mode of the rotor;

5) Sliding bearing oil filmeddy；

6) Oil film oscillation of sliding bearings;

7) Sliding bearing collisionRubbing test；

8) Non contact measurement of radial vibration and axial displacement of the shaft;

9) Sliding bearing axis trajectory;

10) Vibration measurement of bearing seat and platform body;

11) Conduct dynamic balancing of single-sided, double-sided, and multi sided rotors by adding weights;

in total11 types of experiments, analysis methods include:Vibration monitoring and analysis charts: Bode plot, spectrum plot, 3D spectrum, spectrum chromatography, order spectrum, 3D order spectrum, order chromatography, trend analysis chart, bar chart, polar coordinate chart, axis trajectory chart, axis centerline chart, torsional vibration frequency response chart, etc.

1. Main technical indicators:

（1）Range of speed adjustment:0-10000 revolutions per minute/Divided, stepless, digital display speed controller: speed displayed directly;

（2）Type of rotor table:threeCross rotor vibration test bench;

（3）Size (length)X width x height): ≤ 1300mm x 130mm x 210mm;

（4）Number of rotors:6；

（5）Number of shafts:4Root;

（6）Axis size: Φ 10 × 550 (1 piece), Φ 10 × 380（2Root);

（7）Weight:200kg。

2. to configure:

（1）threeCross rotor vibration test bench1 set(including base, spindle, counterweight disk, speed regulating DC motor, spindle support, oil bearing and oil cup, motor support, coupling, eddy current sensor bracket, speed sensor bracket);

（2）Attachment configuration:Oil collection box1 piece, 3 internal hexagonal wrenches, 1 oil injection pot, several screws, sensor bracket6Only coupling4Only, shaft sleeve5 pieces, counterweight plate6Only.

（3）Sensor:

A.speed sensor：

frequency range0.5～1kHz；

Working conditions:0～50℃.

B. Photoelectric sensor

Installed on the shaft at the factorybeEnd;

Working power supply:10～15V；

Operating current30mA；

Working conditions:0～50℃；

Applicable speed range:20～10000RPM；

measure distance10～40mm.

C. Eddy current displacement sensor (2mm range)

The probe model isTwo types: ф 8 and ф 18; Non linearity: 0.2%;

Output method: amplitude limiting± 5V; Power supply: ± 15Vdc to ± 18Vdc;

Temperature range:0～70℃； Installation method: rail or screw installation.