[Mobile Equipment Technology Edition] Daily Question 201802023 Common faults in refrigeration systems (9.5)
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This post was last edited by YORK Industrial Refrigeration on 2018-2-26 07:52. From now on, in order to strengthen exchanges with friends, we have launched a [Daily Question] activity in the Animal Equipment Technology Edition. We hope that everyone will actively participate and make progress and improve together! ! ! award: Actively participate in 3 points of wealth, answer intact 10-15 wealth. This question is valid for two days. No pre-scoring will be given if it exceeds two days. After the screw compressor is repaired, should it be checked whether the energy regulating device can be loaded and unloaded normally? How to check? To answer this question, you must understand how the energy regulating device is loaded and unloaded. When the unit is running, loading and unloading are completed by oil pressure. After we repaired the refrigerator, it would be too cumbersome and wasteful to install it directly on the equipment for testing. Therefore, we will use nitrogen instead of oil to complete the loading and unloading test of the slide valve. If the energy adjustment indicator can smoothly complete the movement from 0 to 100% load position, it is considered qualified! ============================== Premium promotion: Moving equipment---York screw compressor maintenance process https://bbs.hcbbs.com/thread-1806833-1-1.html Moving equipment---York Quantum control center upgrade https://bbs.hcbbs.com/thread-1804837-1-1.html Moving equipment---GEA Grasso screw compressor overhaul https://bbs.hcbbs.com/thread-1800467-1-1.html Moving equipment---Howden screw compressor disassembly and maintenance in the UK https://bbs.hcbbs.com/thread-1832529-1-1.html Moving equipment---Japanese Maekawa MYCOM screw compressor disassembly and maintenance https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=
The energy adjustment of screw refrigeration compressors is generally adjusted by a slide valve. An adjusting slide valve is installed on the body of the screw compressor and becomes a part of the compressor body. It uses the movement of the slide valve to make the volume of the inter-tooth element of the compressor's female and male rotors move from the suction end to the exhaust end during a period of time before the tooth surface contact line moves from the suction end to the exhaust end. The return hole of the slide valve is still connected to the suction orifice, and part of the gas is returned to the suction orifice, that is, the effective working length of the rotor is changed to achieve the purpose of energy regulation. The adjustment range is generally stepless adjustment within 10% to 100%. During the adjustment process, the power and gas transmission volume are almost directly proportional when the load is running above 50%. However, when the gas transmission volume is below 50%, the performance coefficient will drop significantly, making the economy poor.
1. Check the oil system for leaks； 2. Check the wear of the piston ring and whether there is internal leakage ； 3. Check the wear of the regulating solenoid valve and whether there is internal leakage. ； Check coarse and essential oil filters, clean or replace them
It should be checked whether the energy regulating device can be loaded and unloaded normally
The loading and unloading status of the slide valve should be checked. Generally, the sliding valve cylinder can be flushed and deflated through a gas bottle to check the loading and unloading status of the slide valve.
Answer: Should check. Check method: Start the oil pump first, and then start the screw compressor when the oil pressure is normal. Pay attention to its vibration, noise, oil pressure, and oil temperature. When normal operation is achieved, test the energy adjustment device, load and unload it 2 to 3 times, and test the flexibility of its movement. Use manual buttons to load or unload, test the action of the slide valve, and check whether the machine load can be increased from 0% to 100% or reduced from 100% to 0%. At the same time, listen to whether the sound is uniform and whether the exhaust volume is normal. If everything is normal, you can stop the machine.
The energy adjustment of screw refrigeration compressors is generally adjusted by a slide valve. An adjusting slide valve is installed on the body of the screw compressor and becomes a part of the compressor body. It uses the movement of the slide valve to make the volume of the inter-tooth element of the compressor's female and male rotors move from the suction end to the exhaust end during a period of time before the tooth surface contact line moves from the suction end to the exhaust end. The return hole of the slide valve is still connected to the suction orifice, and part of the gas is returned to the suction orifice, that is, the effective working length of the rotor is changed to achieve the purpose of energy regulation. The adjustment range is generally stepless adjustment within 10% to 100%. During the adjustment process, the power and gas transmission volume are almost directly proportional when the load is running above 50%. However, when the gas transmission volume is below 50%, the performance coefficient will drop significantly, making the economy poor.
After repairing the screw compressor, should you check whether the energy regulating device can be loaded and unloaded normally? How to check? The energy conditioning device should be checked for proper unloading. Start the oil pump, adjust the oil pressure to 0.4-0.6MPa, pull the four-way valve or press the load increase and decrease button, check whether the slide valve and energy indicating device are working properly, and finally the energy level indication is at the "0" position.
The energy adjustment of screw refrigeration compressors is generally adjusted by a slide valve. An adjusting slide valve is installed on the body of the screw compressor and becomes a part of the compressor body. It uses the movement of the slide valve to make the volume of the inter-tooth element of the compressor's female and male rotors move from the suction end to the exhaust end during a period of time before the tooth surface contact line moves from the suction end to the exhaust end. The return hole of the slide valve is still connected to the suction orifice, and part of the gas is returned to the suction orifice, that is, the effective working length of the rotor is changed to achieve the purpose of energy regulation. The adjustment range is generally stepless adjustment within 10% to 100%. During the adjustment process, the power and gas transmission volume are almost directly proportional when the load is running above 50%. However, when the gas transmission volume is below 50%, the performance coefficient will drop significantly, making the economy poor.
Okay, not bad, not bad, come down and learn* .
The loading and unloading of the energy regulating device should be checked, which is mainly divided into two steps: First, check the mechanical action. You can flush and deflate the slide valve cylinder through the cylinder to check the action of the slide valve. The second is to operate and adjust the system through the control system and observe the action. The next step is to test the working condition of the energy regulation system during commissioning, and then put it into production operation after it is normal.