High-level oil tank issue
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This post was last edited by sean816 on 2010-11-21 at 12:34. Modern compression units (of the 1-to-2 type, driven by turbines) are equipped with a high-level oil tank. How is the volume of this high-level oil tank calculated? Our unit’s compression units consume a total of 50 liters of oil per hour, but the high-level oil tank has only a capacity of 2.5 liters – isn’t that a bit too small? And there is no emergency oil pump.
For a high-level oil tank, it is sufficient as long as it can ensure sufficient lubrication during the coasting time in the event of an accident involving the unit. The specific size of the tank can be determined based on the unit’s lubrication requirements and coasting time. Generally, an emergency oil pump is sufficient if the unit is equipped with one, as both the emergency oil pump and the high-level oil tank serve the same purpose
Reply to 2# Knowledge Novice: My friend, an emergency oil pump is used when there is a power outage and the AC oil pump cannot operate; it serves to cool the shaft bearings in order to prevent the turbine shaft from overheating. As for the high-level oil tank, it is used to provide oil for the entire unit during idle operation
What was said upstairs is incorrect; the accident oil pump and the high-level oil tank serve the same purpose – to protect the engine. When the accident oil pump cannot start on its own, the low pressure of the lubricating oil causes the check valve in the high-level oil tank to open, thereby supplying oil to the engine. In my opinion, the fuel tanks of yours are a bit small. The idling time for an engine set is usually 10 minutes, and based on that, 8-10 cubic meters of fuel should be required. Personal advice.
Reply to 3# yanjie618901: There are generally two types of oil pumps used in emergency situations, depending on the method of drive. One type relies on a DC oil pump to supply oil when there is a power outage, with the UPS providing the power; the other type uses an impeller pump driven by the main shaft of the unit itself, and oil is supplied as long as the shaft is rotating
The high-level oil tank is also known as the emergency oil tank, and it serves the same purpose as the emergency oil pump. The method of starting the emergency oil pump mentioned by the poster is correct, but the unit will still stop when there is a power outage. The DC emergency oil pump serves to protect the bearings while the unit is running at idle speed. Therefore, the unit is designed with a high-level oil sump, eliminating the need for a DC emergency oil pump, or it has an oil pump but no sump.
Colleagues on the 5th floor, with the engines shut down, can the nacelle oil pump still serve to lubricate the bearings? The engine head oil pump you mentioned is used under normal conditions, while the original poster is discussing situations involving accidents.
Reply to 7# cuili19890105: It’s possible. After the compressor unit stops, the residual pressure in the pipes can be used to drive the shaft pump; just one automatic valve is needed
Going back upstairs, can the residual pressure in the pipelines ensure an adequate supply of oil during the unit’s coasting time? I’m a beginner, so I’m skeptical!
Replying to 9# cuili19890105: Taking our unit as an example, the normal pipeline pressure is 2.4 Mpa. When the compressor stops due to interlock, the automatic valve opens, causing the shaft pump to rotate; fluid is discharged from a 42-inch pipe to a 4-inch pipe, which ensures that the compressor comes to a complete stop without any issues
I believe that the size of the high-level fuel tank is determined based on the coasting time, which is measured in practice. So there’s no need to worry