Issues with replacing lubricant in mechanical pumps
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Our company requires that pumps use different types of lubricants in summer and winter – higher-grade lubricants in summer and lower-grade ones in winter. I wonder if this approach is reasonable I checked the equipment lubrication management regulations, and there are no mandatory requirements in this regard. In the North China Plain where our facility is located, if lubricants of different grades need to be replaced according to the season, when is the appropriate time to do so?
It depends on the local temperature; generally, it is replaced in April and November. If there’s heating in the room, then there’s no need to distinguish between winter and summer. We use 46# turbine oil in summer and 46# refrigeration oil in winter
Depending on the local temperature, if the lowest temperatures in winter are below the pour point of the oil and the equipment is located outdoors, it is advisable to use lubricating oil with a lower pour point. When the temperature is too low, the viscosity of the oil increases accordingly, its fluidity decreases, which affects the lubricating properties of the oil film! So, using lubricant with a lower viscosity in winter is better for the equipment!
Generally, lubricants with higher viscosity are used in summer, while those with lower viscosity are used in winter. We use N68# lubricant in summer and N46# lubricant in winter.
Does the grade mentioned by the poster refer to the viscosity of the oil? The viscosity of oil decreases as the operating temperature rises, and increases as the temperature drops. For details on the impact of lubricant viscosity levels on equipment operation, please refer to the webpage content. http://wenku.baidu.com/view/9aa634160b4e767f5acfceee.html
I don’t understand why cold-temperature engine oil is used on the second floor; cold-temperature engine oil only differs slightly in terms of performance at low temperatures. The temperature during pump operation should be around 30–50 degrees, right?
It depends on the conditions of the equipment itself and the local temperature differences. Special oils need to be replaced regularly. Oil samples are tested regularly, and decisions are made based on the operating conditions of the equipment. If the temperature difference has little impact on the lubrication system, there is no need to replace it.
Does it move around the equator in summer and around the North Pole in winter?
The viscosity of lubricating oil is related to the operating temperature in the environment, and it certainly needs to be changed according to those conditions; there’s no doubt about that.
Use L-AN46# in summer (the old designation is 20#), and use L-AN32# in winter (the old designation is 30#)
This is because ordinary lubricants generally have the property that their viscosity decreases at high temperatures and increases at low temperatures. Therefore, the compressor needs to select the appropriate lubricant depending on the different seasons, that is, depending on the different temperatures. In our country, the higher the grade of lubricating oil, the greater its viscosity. Therefore, where conditions permit, the lubricating oils used in winter and summer should be different. In conventional compressors, the cylinder packing section uses compressor oil grade 19 in summer and grade 18 in winter. The crankshaft-conrod section can use 50-grade machine oil in summer. In winter, machine oil grades 30 or 40 can be used, which provides better lubrication for the compressor. Generally, single-acting small compressors use compressor oil grade 13 in winter and grade 19 in summer. Depending on the characteristics of the compressor’s structure, different methods can be used for lubrication. The following are the various approaches: 1. Pressure lubrication – This method involves using mechanical means to apply lubricating oil under pressure to the relevant parts; it is also known as pressure-fed lubrication. 2. Splashing lubrication method -- An oil injection rod mounted on the connecting rod sprays oil, causing it to splash onto various lubrication points; as a result, the cylinder and the moving mechanisms can only use the same type of lubricant. 3. Spray lubrication method – The oil mist sprayed is carried by gas to the lubrication areas such as cylinders; ultra-high pressure compressors, vane compressors, and screw compressors all use oil spray lubrication. 4. Oil drip lubrication method -- Using an oil cup and oil delivery pipes to supply lubricant to the components that need it, or adding lubricant regularly with an oil can.