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Minmetals Yingkou Medium Plate Co., Ltd. has two sets of the Power Plant
15000m3 / h air separation unit (1 #, 2 # ASU), its supporting
Import 2X2MSGE + 3ARC / 30 machine using pressurized air 4
Level compression, two sets of gear box of a centrifugal compressor, the main design parameters
As follows: entrance flow 28000m3 / h, the entrance pressure 0157MPa, Pai
Gas pressure 613MPa.
1 vibration value of the high -
111 fault phenomenon
July 1, 2006 to arrange for an air separation plant 1 # air pressurization
Machine maintenance, mainly the disintegration of water to clean the oil cooler side of the dirt to improve the
Its cooling efficiency; At the same time, replaced the 1-4 rotor vibration probe
(Air-pressurized aircraft from October 2003 to run for the first time in more
Probe for vibration). After overhaul in the process of testing and found a loaded,
4-axis vibration of the rotor increases the value of a sudden, when the pressure rose to
413MPa, the value of excessive vibration, air supercharger drive chain jumping.
Preliminary analysis of the view that the replacement of vibration in the probe after the
A four-axis vibration of the phenomenon of increased value, the probe may be the quality of
Or the installation of quality problems. So check the demolition of a four vibration
Probe whether the end of the protection layer bumps, and re-install the probe. An
Equipment to be cautious since there is no visual distance, when the touch probe
And then returned to the shaft wall, and then measurement of gap voltage, and then according to space
From the voltage regulator, and confirmed by the inspection accuracy. Mechanical inspection
Scroll bolts connecting the entrance and found no signs of loosening.
And a second test, when the pressurized air to the machine load
210MPa when a rotor shaft vibration value of 19μm, 4 to
Sub-axial vibration value of 17μm. Use of hand held vibrometer for vibration detection
Fixed value of: a rotor 18μm, four rotor 15μm. When the air
Pressurized gas to drive to load more than 413MPa, a four-axis rotor
Vibration value of the rapid increase in vehicle air-pressurized aircraft. Rotor shaft vibration level
Fixed value increased from 19μm to 43μm, 4-axis vibration value of the rotor by
17μm up to 35μm, the air supercharger rotor shaft vibration chain
Values shown in Table 1.
Table 1 of pressurized air rotor shaft vibration value chain
Unit: μm
Name
Alarm value of the value of parking
Low-limit high-limit low-limit high-limit
Rotor 1 - 34 - 43
Rotor 2 - 31 - 39
Third, the rotor 4 - 28 - 35
112 reasons for inspection and analysis of fault
Two test aircraft air pressurization failure, it is necessary to determine a
4-axis vibration of the rotor of the reasons for increased value. First of all, based on careful instrument
Measured a vibration probe 4 gap voltage, determines that there is no question
Title; also examined a 4 rotor connector import and export of various ministries, but also
No problem. Then immediately contact the manufacturer of professional maintenance personnel to
Confirmation test at the scene. Professional Vibration Analysis with Data Acquisition
Online analysis instrument, the result also reflects a four rotor
Excessive shaft vibration value. As a result of three kinds of detection methods (vibration detection
Head, hand-held instrument and vibration analyzer vibration data acquisition) test
Results are consistent, so to determine the value of the rotor shaft vibration due to the high turn
Son itself.
The disintegration of the two groups to check the air pressurization machine gear box, in the demolition of the entrance
Vane found that between the guide vanes and the volute has a junction deformation
Pieces of stainless steel (specification: 10mm × 6mm × 1mm) will be a
Injured parts of the entrance of the impeller blades, the rotor-side bearing clearance of the load value
To 0127mm. When the demolition of four rotor impeller also found when scraping
Injury phenomenon, fixed diffuser plate 4 of the 12 broken screws M5
A 5, diffuser plate to adjust the nine stainless steel gasket (specifications:
0105mm) lost one-third of both the rotor bearing surface 4
There is the phenomenon of carbonized film.
11211 rotor vibration level
Pieces of stainless steel pipe will be injured impeller, rotor dynamic Ping
The destruction of value, the load-side gap increases bearing wear.
Vibration causes the rotor 4 11212
Impeller was foreign body abrasions, diffuser plate broken screws, expansion
Adjust the voltage set to be blown gasket broken, and fell by a third, the destruction
Balancing the rotor.
11,213 Diffuser screw plate fixation Fracture
Due to the fixed diffuser plate screw loose, diffuser plate and the cochlear
Shell formed a gap between the high-pressure air into the diffuser plate pad adjustment
After letters from the Department gas leak, the air pressurized aircraft run-off long-term
Process was broken high-pressure air blowing extrusion of the gasket together to form a
Types of outward expansion, and will be crowded off the screw by stars.
113 excluded from the measures
(1) a, 4 rotor removed, sent to the manufacturer
Impeller repair damage, re-adjust the dynamic balance of the rotor.
(2) replace the diffuser pads to adjust and switch to non-0145mm
The production of steel re-adjusted Rust pads in order to increase the strength of pads. And
Will cut off the diffuser plate screws removed all the original
M5 thread hole hole wire M6 changed in order to increase the strength of screws.
(3) the replacement of a load-side rotor bearing and rotor 4 bilateral
Bearings, the replacement of a three-tier oil seal (oil is running in the phenomenon),
Re-adjustment of a four rotor vibration probe gap voltage.
(4) the dissolution of the three, four coolers, the removal of diffuser plate, the prosecution
Blown investigation and removal of foreign bodies such as pieces of the gasket. Bottom gear pin fastening screw
Silk, check the centering unit value.
Disposed of after the conducting air-pressurized the first load test
Vehicles. When loaded to 610MPa, the level to maintain the value of the rotor shaft vibration
In 11 ~ 13μm, unchanged; 4 rotor shaft vibration value
Maintained at 20 ~ 23μm, and with a slight increase in pressure rise.
Come to light of the above two solutions.
The first option: dynamic balance of rotor has been done to deal with, if
Outlet pressure will be set up in the air pressurization below 610MPa machine can be transported
Line and wait for the rotor in place after the replacement of spare parts. However, spare parts
Arrive at least a cycle of more than half a year, during which not sure really
Paul-axis vibration value of the rotor 4 is no longer rising.
The second program: four rotor shaft vibration of high value because
Balancing enough accuracy. Order to completely rule out the failure, will have to re -
The disintegration of gear box, the removal of the rotor 4 and the manufacturer to re -
Correction Balancing the need to increase the two-day inspection period.
In order to ensure the air supercharger drive in an air separation plant until repairs before
During the operation there is no problem, and finally decided to adopt the second side
Case, re-do the demolition of four rotor dynamic balance. Re-install, the first
When the second load test rotor shaft vibration levels drop to 15 ~
18μm. The author believes that although the four-axis vibration of the rotor of a higher value
, But relatively stable, safe operation of air-pressurized aircraft.
In order not to affect the production, decided to let the air pressurized plane normal to start
Run. During operation of the air pressurized to strengthen inspection machine and
Close attention to a value of four rotor shaft vibration trend of development, to ensure that the set
Preparation of normal operation.
2 vibration fluctuations in the value of drift
November 12, 2007 rotor parts all in place,
1 # big overhaul ASU. During this period, the air pressurized aircraft transported a total of
Line a year and a half hours, during which the operating normally, a four-axis rotor
Vibration value will remain basically unchanged.
211 fault phenomenon
The overhaul, the replacement of the air pressurized machine a 4 to
Son of load bearing side, gas seal, diffuser plate 4 pads and adjustment
Probe vibration. Overhaul the air pressurization load test machine, a
Value of the rotor shaft vibration level from 13μm down to 10μm, and
4 rotor shaft vibration value of 24 ~ 32μm, the value of close to jumping, and
Axis vibration value and drift up and down, great range.
212 Failure Analysis
In a thorough overhaul in the replacement of defective parts and components, thus
Not in the maintenance of quality problems. Must find from other sources
The cause of the malfunction, the focus should be confirmed that the rotor vibration probe 4 is
Whether there is a problem because only four rotor vibration probe the location of the installation
In the spiral case and the gear box between the exposure to external and also the most easily
Problems of weak links.
Through on many occasions to be demolished, and adjustment of the probe, found that four
Site-level cantilever probe is too long, sufficient strength, the location of the probe installation
Happens to be the replacement of the gas leak closed part of the airflow to the Purge, making detection
The first measurement data up and down drift, the formation of false data. The cause of the malfunction is
In the design, installation deficiencies and shortcomings.
Improvement measures and the effect of 213
The installation of the original design of the probe out to dismantle the base, re -
Design, production. When installing the probe, the cantilever probe to reduce fixed
Length to increase its strength. Adjustment of the probe is installed, the air pressurized aircraft
For load testing, rotor shaft vibration levels from the original value of 18μm
Down to 10μm, the problem completely resolved. Pressurized air before and after maintenance
Machine a 4-axis vibration of the rotor changes the value in table 2.
Table 2 repair a machine before and after the air-pressurized, four changes in the value of the rotor shaft vibration table
Unit: μm
Rotor rotor 4 at the project level
Maintenance of the top 16 ~ 18 12 ~ 14
Replacement of the probe test after the 19 ~ 43 17 ~ 35
The first test after overhaul 11 ~ 13 20 ~ 23
Maintenance of the second test 11 ~ 13 15 ~ 18
Overhaul of the first test after 10 ~ 11 24 ~ 32
Overhaul of the second test after 10 ~ 11 9 ~ 10
At present, the air pressurized aircraft has been in operation for the stability of more than 8
Months, production for the company to provide a strong protection.
3 Conclusion
Through the two air pressurized rotor shaft vibration values so high
Impaired processing, recognize the failure of an air separation plant to fully develop the analysis
Ideas and issues from various aspects of the detailed, in-depth analysis, this
Like the cause of the malfunction can be detected at an early date and to find reasonable measures to make air
Separation plant to resume normal operation as soon as possible.