What should be the temperature of the crankcase lubricating oil in a reciprocating compressor (with three-stage compression) – for Great Wall L-DAB100#?
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We have reciprocating compressors with three-stage compression on site, and the lubricating oil used in the crankcase is Great Wall No. 100. What is an appropriate temperature for this lubricating oil during operation and when there is oil leakage? What are the effects if the oil temperature is too high? For operation purposes, does it mean the pressure difference across the oil filter is relatively high? Will temperature have an impact on the lubrication of the crankshaft and journal bearings (when not in operation)?
It is appropriate to keep the temperature between 40 and 42 degrees Celsius during operation and when oil leaks are occurring. The viscosity-temperature characteristics are best at an oil temperature of 40 degrees Celsius. If the oil temperature is too low, its viscosity becomes too high, resulting in poor lubrication.
If there is oil leakage, a slightly lower oil temperature should have little impact, right? After all, there is no relative motion at the lubricated area. The problem we are facing at the moment is preventing freezing of the oil cooler; if we do not use circulating cooling water, there is a risk that the oil cooler will get damaged from freezing. However, when circulating water is used, the oil temperature remains around 24 degrees (the temperature of the circulating water is 28 degrees, and it drops to around 20 degrees by the time it reaches the oil cooler). Therefore, deciding whether to use circulating water for the standby unit is a challenging issue!
If there is oil leakage, a slightly lower oil temperature should have little impact, right? After all, there is no relative motion at the lubricated area. The problem we are facing at the moment is preventing freezing of the oil cooler; if we do not use circulating cooling water, there is a risk that the oil cooler will get damaged from freezing. However, when circulating water is used, the oil temperature remains around 24 degrees (the temperature of the circulating water is 28 degrees, and it drops to around 20 degrees by the time it reaches the oil cooler). Therefore, deciding whether to use circulating water for the standby unit is a challenging issue!
Using cooling water from the standby unit can keep the oil temperature at 28 degrees Celsius; in winter, without circulating water, the oil temperature is even lower. For this reason, the circulating water in winter serves a heating function; it must not be stopped and must be in use.
The backup unit here is constantly leaking oil; the temperature of the lubricating oil rises to around 40 degrees after being pressurized, and the cooling water is used to lower this temperature
Although it will cool down. If you turn off the cooling water, it might be accidentally turned on again when starting up, causing even more **troubles. When there is oil leakage, you can turn down the cooling water valve; after starting the machine, turn it back to the normal position.
25-40 is appropriate; if the temperature is too low, the oil viscosity increases, making it difficult to form an oil film that can provide lubrication between the bearing surfaces. When the temperature is low and viscosity is high, the pressure difference across the oil filter is definitely large. The last one has no impact; regular turning of the shaft is necessary, and the oil system should be activated during this process.
Does the backup compressor run with oil as well? It’s still the regular turning of the shaft you mentioned; oil leaks occur during this process
No need; it just needs to rotate during cranking. It should be kept warm in winter.
Here, the backup machines also run on gasoline all the time, whether in winter or summer