This standard specifies the conditions, equipment and methods for the performance test of wet Roots vacuum pumps that exhaust directly into the human space. This standard applies to the performance test of wet Roots vacuum pumps. QB/T 1445-1992 Performance test method of wet Roots vacuum pumps QB/T1445-1992 Standard download decompression password: www.bzxz.net

Light Industry Industry Standard of the People's Republic of China
Performance Test Method of Wet Roots Vacuum Pumpwww.bzxz.net
Subject Content and Scope of Application
QB/T1445—1992
This standard specifies the conditions, devices and methods for the performance test of wet Roots vacuum pumps that exhaust directly into the human space. This standard applies to the performance test of wet Roots vacuum pumps. 2 Test Conditions
The following conditions should be met during the test:
The difference between the actual speed of the pump and the design speed is not greater than ±5%; the pump inlet is continuously filled with appropriate clean water; b.
The test environment temperature is 5~~35℃.
3 Test Device
3.1 Vacuum Gauge
Single-tube mercury pressure gauge or vacuum pressure gauge not less than 0.4 level or other pressure instruments that can meet the test and accuracy requirements. 3.2 Flowmeter
According to the measured flow rate, select glass rotor flowmeters with different flow ranges and an accuracy of not less than 2.5. The upper limit flow value of the flowmeter should not be less than 1.6 times the maximum value of the measured flow. If a single flowmeter cannot meet the requirements, two or more flowmeters can be used together. Other flowmeters that can meet the test and accuracy requirements are allowed to be used, and the corresponding calculation methods are given. 3.3 Other instruments
Tachometer,
0.5 level voltmeter, ammeter, power meter or other dynamometer; sound level meter;
Thermometer:
e. Barometer.
3.4 ​​Test bench
The test bench is shown in the figure. The glass rotor flowmeter should be installed vertically, and the distance between the flange plane of the lower air inlet and the ground should not be less than 200mm. Supplementary sealing water pipes and pressure gauges are installed at the pump inlet to replenish sealing water and display the vacuum degree in the system during testing. Approved by the Ministry of Light Industry of the People's Republic of China on February 21, 199238
quasi-thermal network
implemented on August 1, 1992
gas-water mixture
QB/T1445--1992
air
1 base; 2-vacuum pump; 3-water inlet switch; 4-vacuum gauge; 5-main line; 6-manual valve; 7-glass rotor flowmeter test bench schematic diagram
4 test method
4.1 principle
Use the "constant pressure method" to test the pumping speed of the pump, that is, during the test flow process, the vacuum degree in the vacuum system remains unchanged. 4.2 steps
Install the pump on the test bench according to the figure, close the manual valve (6) by about 1/2, then start the pump, open the water inlet switch (3), and after the pump runs smoothly, adjust the valve (6) to obtain different vacuum degrees. It is recommended to adjust to the lowest value of vacuum first, and then adjust it up in sequence. Each vacuum degree should measure its corresponding pumping speed, rotation speed, shaft power, measure no less than 8 vacuum points, and measure the noise under rated vacuum degree.
4.3 Calculation of pumping speed
aCalculation formula
60(p2-)Np2T)
Where: Q-
-Pumping speed under suction state, m/min;
-Rotameter flowmeter indication, m2/h;
Standard state atmospheric pressure, MPa (take pi=0.101MPa); Measured atmospheric pressure, MPa;
p—Vacuum degree (vacuum gauge indication), MPa; Thermodynamic temperature of standard state (T,=293K); Ti
-Thermodynamic temperature during test, K (T2=273K+test gas temperature). When the actual speed is different from the design speed, the Q value is corrected according to formula (2). Q =Qn
Wherein: Q—the pumping speed at the design speed, m\/min; Q-the pumping speed at the measured speed calculated according to formula (1), m/min; n
the design speed, r/min;
the measured speed, r/min.
4.4 Calculation of pump shaft power
Quasi-thermal
(1)
·(2)
Where: N pump shaft power, kw;
I-—current, A;
V-—voltage, V;
cosg--—motor power factor;
n1-motor efficiency, %;
QB/T1445—1992
n2——belt rotation efficiency (take n2=95%). Test report
Y3 IVcostni72
·(3)
Fill in the test results in Appendix A (supplement) "Wet Roots vacuum pump performance test record", and draw the pumping speed-vacuum degree, power-vacuum degree curve, that is, Q-force, Np curve. 40
Standard access network NAT
om class standard industry data wide. Free download
Roots vacuum pump
Test medium
Recorder
Maximum pumping speed
Inlet diameter
Working volume
Vacuum degree
Additional instructions:
# Number
QB/T1445--1992
Appendix A
Performance test record sheet of wet Roots vacuum pump (supplement)
Performance test record sheet of wet Roots vacuum pump original data
Model:
m\/min;Speed
_r/min,
mmRated pumping speed m/min,
Flowmeter
Test location
Calculator
This standard is proposed by the Technical Equipment Department of the Ministry of Light Industry. Noise
This standard is under the jurisdiction of the National Light Industry Machinery Standardization Center. Motor
%Speed
Power factor cosn
Actual pumping speed
This standard was drafted by Shenyang Paper Machinery Factory and Sichuan Light Industry Machinery Factory. The main drafters of this standard are Rong Huahuan and Sun Tianrong. Standard search network.bz
mStandard travel fee
Shaft power
Volume power
r/mint
Test date
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