【Weekly Topic】(The winner of the big prize is announced every Monday; common equipment failures) 2011.08.15-08.22
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This post was last edited by hannianlong on 2011-8-20 at 11:06. Let’s discuss (common equipment failures, their causes, and methods of diagnosis). For example: Centrifugal pumps (used in circulating water systems). Failures: Cavitation often occurs, damaging the pump. Methods of diagnosis: Fluctuations in current, fluctuations in outlet pressure, and fluctuations in flow rate occur during cavitation. Causes: This pump suffers from cavitation frequently; it is determined that the high installation height is the cause of such cavitation. * l: X8 ^5 1. Please feel free to share your thoughts and post based on your own understanding； 2. For regular responses (i.e., those that include meaningful analysis or discussion), a reward of 5 to 20 wealth points or 1 to 3 charm points is given; more generous rewards are offered for in-depth analyses, as well as forward-looking and accurate responses
Spiral coal feeder: Fault: Frequent jamming. Diagnosis: Increased current and rising furnace temperature. Reason: The coal contains impurities such as wood and iron pieces ； The shaft of the spiral coal feeder is out of alignment.
Reply 1# hannianlong For example: Centrifugal pump. Fault: Overheating of bearings. Methods for diagnosis: Touching with hands, infrared thermometer. Causes: Damaged bearings, improper bearing clearance or installation, inadequate lubrication, bent pump shaft, misaligned couplings. m; ?2 p7 m% o/ N' _+ ]9 S
Compressor motor renovation: There was originally a compressor with a capacity of 420 cubic feet, equipped with a motor of 1400 KW and operating at 2950 revolutions per minute. Modification was carried out due to the motor being too small. The motor capacity has been increased from 1400KW to 1600KW. The foundation remains unchanged. The motor has a special structure. After the modification, testing revealed a vibration level of 0.08 mm. Judgment: 1. Dynamic balance issue. 2. Alignment issue. 3. Bearing issues. Judgment method: Touching by hand, vibration meter. Reason: 1. The motor was sent back to the factory for balancing, and the balancing was done properly. 2. There is no gap between the bearing and the bearing cover. 3. Alignment is proper. The vibration during another test run was 0.042.
Equipment name: Centrifuge. Fault: Shutdown due to high vibration. Detection method: High machine vibration triggers an interlocked shutdown. Solution: Stabilize the feed rate and composition； Inspection and maintenance of the equipment itself.
Equipment name: Centrifugal pump. Fault: Leakage in the mechanical seal (double-face seal). Detection method: Drop in the liquid level of the mechanical seal flushing tank. Solution: Replace the damaged seal components
Equipment name: Piston compressor. Fault: Carbon buildup on the valve plates of the second stage. Detection method: High exhaust temperature and pressure in the first stage. Solution: Clean the intake valve of the second stage
Equipment name: Centrifugal compressor. Fault: Poor dynamic balance of the rotor. Diagnosis method: Collect vibration data and create a spectrum diagram. Solution: Achieve dynamic balance for the rotor
Equipment name: Reciprocating diaphragm metering pump. Fault: Diaphragm leakage. Diagnosis method: Open the tank to check for the presence of the medium being transported. Solution: Replace the diaphragm
This post was last edited by sefcat on 2011-8-15 at 19:42. Equipment name: Ultra-high pressure reciprocating compressor. Fault: Packing leakage. Detection method: Check for bubbles in the packing cooling oil return line, as well as any frost formation on the outer wall of the machine at the packing area (high-pressure gas leakage absorbs heat from the surrounding area). Solution: Disassemble and replace the packing assembly
Equipment name: Reciprocating compressor. Fault: Air valve leakage. Diagnosis method: If the intake valve leaks, the pressure cannot rise; if the exhaust valve leaks, the exhaust temperature increases and the exhaust pressure rises. Solution: Repair the air valve, or replace it