This standard specifies the requirements for instruments for measuring the vibration severity of rotating and reciprocating machines. This standard applies to the measurement of the vibration severity of rotating or reciprocating machines in accordance with GB6075. GB/T 13824-1992 Requirements for vibration severity measuring instruments GB/T13824-1992 Standard download decompression password: www.bzxz.net
This standard specifies the requirements for instruments for measuring the vibration severity of rotating and reciprocating machines. This standard applies to the measurement of the vibration severity of rotating or reciprocating machines in accordance with GB6075.
Some standard content:
National Standard of the People's Republic of China Requirements for instruments forming vibration intensity measuring instruments Requirements for instruments forming vibration intensity measuring instruments This standard is equivalent to the international standard 1S02954-1987 Mechanical vibration of rotating and reciprocating machines - Requirements". 1 Subject content and scope of application This standard specifies the requirements for instruments for measuring vibration intensity of rotating and reciprocating machines. This standard is applicable to the measurement of the moving intensity of rotating or reciprocating machines according to GB6075. 2 Reference standards GB2298 Mechanical vibration and shock terminology GB6075 Basis for the formulation of machine vibration standards 3 General requirements GB/T13824-92 For vibration intensity measuring instruments The maximum root mean square value of vibration velocity is defined as the unit for measuring machine vibration intensity. Therefore, instruments that meet this standard should be able to directly indicate or record the root mean square value of vibration velocity. Appendix A gives the method for checking the true root mean square value indication. Vibration measuring instruments usually include vibration sensors, amplifiers with frequency compensation, indicating or recording instruments, and power supplies. 3.1 The frequency range of vibration intensity measuring instruments should be 10~1 000Hz. 3.2 The ratio of the sensitivity value in the measurement frequency band to the 80Hz reference sensitivity value is called relative sensitivity, and its deviation should not exceed the value given in the following table. The following table lists the sensitivity deviation limits allowed in the frequency range of 1~10000Hz. FrequencyWww.bzxZ.net 10:000 Nominal value Relative sensitivity Minimum value Maximum value In order to minimize the error caused by vibration outside the measurement frequency range, the sensitivity should drop rapidly in the manner specified in the above table and the figure below at the limit frequency. The figure below shows the change process of the nominal value of relative sensitivity in the entire frequency range of 1 to 10000Hz and the permitted deviation limit value. Relative I divergence *Tolerance line GB/T13824—92 Test point n1.622.5346681L.62238456#1u1.622.634568u1.622.5346810Frequency car, z\ Nominal value and permissible deviation limit of relative sensitivity In some cases, in order to avoid interfering vibrations that are not related to the vibration characteristics of the evaluated machine, it is necessary to "The upper and lower limits of the measured frequency range are gradually limited. For this purpose, the instrument can be equipped with additional high and low filters. It is recommended to select the cut-off frequency and edge steepness of this filter in accordance with the provisions of the International Electrotechnical Commission (IEC). 3.3 When selecting the range, the indication of the lowest vibration intensity value to be measured should be at least equal to 30% of the full-scale value. The maximum and minimum values of the vibration intensity range should be stated (according to Table 1 in GB6075). For example, the vibration intensity measurement with a range of 0.28 to 28 mm/s". 3.4 The error of the vibration intensity measuring instrument is composed of the allowable deviation of the frequency response given in Article 3.2 and the calibration error of the absolute value of the sensitivity at the base frequency of 80 Hz. The maximum value of the measurement error can be 10% of the indicated value, including the calibration error at 80 Hz of the full base value. The measurement error of vibration sensors and indicating instruments (see 4.8 and 5.4), various types of vibration sensor fixtures (see Chapter 4), and various lengths of connecting cables between vibration sensors and indicating instruments provided by the manufacturer (see 4.14) shall not exceed the above limit values within the entire permissible operating temperature range and when the power supply voltage fluctuates by ±10%. 3.5 The sensor should be calibrated by the vibration excitation method. The deviation between the vibration direction and the sensitive axis of the sensor should not exceed ±5°. The total harmonic distortion of the excitation vibration velocity should not exceed 5%, and the error of the excitation vibration velocity should be within ±3% within the entire measurement frequency range. The vibration intensity instrument should be calibrated at room temperature of 20 ±5° and at a frequency of 80Hz using a vibration level of Vra=100n1m/s. 4 Requirements for vibration sensors and connecting cables 4.1 Inertial vibration sensors should be used to measure the vibration of the object being measured relative to a stationary reference system. 4.2 The vibration sensor should be rigidly fixed to the object to be measured. No mechanical resonance should occur in the mechanical fixings or the sensor itself within the sensor operating frequency band. 4.3 In the entire measurement frequency range, the lateral sensitivity ratio of the sensor should be less than 10% for the fixing method that complies with the relevant standards. The maximum value of the linear response of the vibration velocity of the sensor in the direction of the desensitizing axis should be at least three times the full-scale vibration velocity. GR/T13824--92 4.4 In order to show the degree of influence of the vibration sensor on the object to be measured, the effective mass of the vibration sensor should be given. In order to make it suitable for more fields, its mass should be as small as possible. The following method can be used to determine whether the mass of the sensor is excessive: double the mass of the sensor by adding a mass. If the new reading is 12% worse than the original, it means that the mass of the vibration sensor is too large relative to the object being measured, and its measurement result should be eliminated. 4.5 The amplitude and frequency range of the vibration sensor should be sufficient to avoid exceeding the allowable measurement error specified in Article 3.4. 4.6 The sensor should be able to withstand at least one times the maximum specified vibration input value in all directions without changing its performance. 4.7 Equivalent to the self-excited interference caused by hum and noise The input quantity and the equivalent input quantity of the external interference and external excitation generated by the interference field, when their sizes are as follows, have no effect on the measurement. When the obtained value is related to the direction of the instrument in the field, the unfavorable value should be taken. The manufacturer shall give the test results under the following interference: 4.7.1 The sensor shall withstand a uniform magnetic field strength of 100A/m, 50Hz or 60Hz. The magnetic field strength shall be measured before inserting the sensor. 4.7.2 The sensor shall withstand a uniform air noise field with an effective sound pressure value of 100 dB relative to a reference value of 2×10-'Pa in each octave. Such sound pressure values can be generated by a random noise signal generator or a frequency signal generator in the frequency range of 32 to 2000Hz. 4.7.3 If the sensor and the measured object are conductively connected, and the indicator is operated on the grid voltage, the ground terminal of the sensor shall be provided with an effective value of 100 mA power frequency ground current and discharge it at the ground terminal of the indicating device. 4.8 The operating temperature range of the vibration sensor and connecting cable should be given. Within this range, the measurement uncertainty should not exceed the forging limit value specified in Article 3.4. 4.9 The allowable temperature range that the sensor and connecting cable can withstand without being damaged should be given. 4.10 The maximum limit value of non-working vibration and impact in any direction that the sensor can withstand without being damaged should be given. 4.11 The maximum humidity value that the sensor and connecting cable (including additional cables) can withstand and continue to work normally should be given. If the sensor can be used in any other harsh environment, the ability of the sensor to withstand such an environment should be given. 42 The strain sensitivity of the sensor on its mounting surface caused by the base should be given. 4.13 The expected life and test cycle of the sensor shall be given. 4.14 If there is a connecting cable between the vibration sensor and the indicating instrument, its length shall be at least 1 m. The manufacturer shall indicate what additional extension cables can be used without exceeding the tolerances given in 1.5. Requirements for indicating instruments 5.1 The indicating instrument may be a pointer instrument, a graphic recorder or a digital display instrument. The scale shall be marked in rm (mm/s). 5.1.1 The instrument shall be able to indicate the true root mean square value of the vibration velocity. 5.1.2 The calibration error of the instrument shall not exceed ± 2.5% of the full scale value. 5.1.3 The value below 1/5 of the full scale value shall be easily read on the indicating part of the instrument. 5.2 When a sinusoidal signal with a frequency within the measurement frequency range and an amplitude of 70% of the full scale value is applied to the corresponding voltage input of the indicator, its initial overshoot shall not exceed 10% of the final reading. When the peak value difference of the pointer oscillation is compared with the final position of the pointer, its maximum value should not be less than 1.5 of the full scale value, and no negative impact should occur. 5.3 There should be a device to check the magnification. It can be used to adjust the total magnification of the indicator with an error of ±20 at a specified frequency (for example, 50Hz). 5.4 The operating temperature range of the indicating instrument should be given.5 The maximum humidity that the indicating instrument can withstand and continue to work normally should be given. If the indicating instrument is used in any other harsh environment, the ability of the indicating instrument to withstand such environment should be indicated. 6 Requirements for power supply The requirements for the input power supply of the sensor and the indicating instrument should be specified. A1 Test circuit GB/T13824-92 Appendix A Test method for root mean square value (effective value) voltage indicator (reference) Real effective value table Side generator Positive recovery wave generator W——Network diagram of the frequency response of the instrument under test A1 Test circuit of effective value voltage indicator The following method can be used as a test method suitable for effective value voltage indicator. The values given are based on the definition of the crest factor: crest factor wherein, is the larger amplitude of the general asymmetric rectangular wave shown in Figure A1 (i.e., U, U, whichever is larger); i is the effective value of the waveform. From the definition, we know that For the general case shown in Figure A1, it can be expressed as: ua+i Three special cases of the test circuit: a. Symmetric square wave U, = Unit = T/2 b. Asymmetric square wave There are two types of asymmetric square waves: (a) U. > U.., T/2 (b)U,U.,t; =T/2 c. Rectangular pulse wave Uh = 0,t, Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.