Regarding problems that arise in the actual operation of reciprocating compressors.
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There are two Burkhard vertical four-stage reciprocating compressors in our workshop, one with one circuit, and one with four circuits and two bypass regulating valves. The two machines operate in parallel, and the process gas is crude carbon monoxide. There have been some problems during the operation, and I hope experts can give some solutions. 1. Two compressors are of the same model, but the operating current of one is generally more than ten A higher than that of the other. What may be the problem? 2. The three-stage outlet pressure of one of them (the one with the higher current) is overpressured. It is judged that the fourth-stage inlet valve is internally leaking. However, after replacement, there is only a slight improvement and there is still overpressure. What is the reason? 3. For a period of time, the water separated by the secondary inlet separator was much less than normal, and this happened to both machines at about the same time. What is the specific reason? 4. The lubricating oil was replaced during the maintenance of the compressor this year, but not long after the machine was started, the lubricating oil pressure of one of them dropped continuously (by jiyai). It was suspected that the oil filter screen was blocked, and no foreign matter was found after switching and cleaning. After replacement, there was a slight improvement, but the pressure still dropped quickly. Later, I ordered two new ones from the manufacturer and replaced them before the problem was solved. I think it's strange. Is it because the filter screen is blocked? If it is because of the filter screen, why was there no problem with the filter screen before changing the oil? Moreover, the oil has been newly changed, and the crankcase has been thoroughly cleaned during maintenance. There should be no impurities. After the problem occurred, I tried steam cleaning (by jiyai) but it still didn't work. 5. Each separator drain valve group is equipped with a flow-limiting orifice plate. The holes are very small, and the drain valve is often blocked. I would like to ask if the two orifice plates can be removed, or the holes can be appropriately enlarged?
1The compressor with high current has a heavy load； 2. Check whether the four-stage piston ring is seriously worn, causing the cylinder gap to increase and causing the third-stage overpressure. ； Check whether the fourth-stage suction and exhaust valves are damaged or not closed tightly, causing the cylinder gap to increase and causing the third-stage overpressure. ； 3. The water content in your raw gas is low during that period. ； 4. It may be that there are impurities in the newly replaced oil, causing the filter to become clogged, or the oil temperature is not properly controlled when you are running and the oil temperature is too low, causing the oil pressure after the filter to drop. ； 5. You need to consult the manufacturer whether you can remove the flow-limiting orifice plate or enlarge the flow-limiting orifice. He designed such a small flow-limiting orifice plate for safety reasons.
1. If the current is high, it means that the power consumption of the compressor is high. If the exhaust volume and intake and exhaust pressure do not change, it may be a manufacturing problem. Furthermore, some on-site ammeters have deviations. I don’t know how much power you have and whether the deviation is within a reasonable range.； 2 Level three overpressure has many causes, which should be considered based on the exhaust temperature. 3 Agree with the person above, it should be because there is less water in the raw materials. ； 4 To provide an idea, have you paid attention to the changes in oil temperature? I don’t know what grade of compressor oil you are using. Oil temperature has a great influence on pressure. ； 5. The flow-limiting orifice plate is designed for safety reasons, but this is the case for foreigners. We * * Most compressor factories do not design orifice plates, so I think they can be removed, but you must pay attention to the liquid level when draining the liquid, and do not drain it, which may cause danger.
Check the inlet and exhaust valves of the next stage. Check whether the large wear of the third- and fourth-stage piston rings is out of tolerance, causing air blow-by before and after the piston. Check whether the diameter of the third- and fourth-stage cylinders is too large, etc., resulting in a reverse pressure difference. Check whether the oil is flowing smoothly.
1. The high current may be caused by the high discharge pressure of the third stage. 2. The separated water content is much less than normal, which is directly related to your process gas. 3. Is your oil inlet filter clogged? Is your oil filter disposable? 4. It is best to seek advice from the manufacturer for the flow-limiting orifice plate, or to increase it appropriately. Because it involves sewage safety issues.