Transient voltage surge, main oil pump and auxiliary oil pump in the centrifugal compressor oil station.

No action is required; the auxiliary oil pump supplies oil automatically to maintain lubrication. Once the time is reached, it can be prepared to start up again.

This post was last edited by ssln123 on 2018-6-29 at 16:06. If a low oil pressure interlock delay is set, and this delay is longer than the time it takes for the auxiliary oil pump to establish normal oil pressure after starting up, then the compressor will not shut down. However, in reality, the oil pressure can only be delayed for a few seconds; it takes longer for the pump to generate oil pressure. After the compressor is reset, start it up normally.

This is a slight drop in oil pressure; the unit will not shut down. If interlocks are in place, it is necessary to wait for those interlocks to be reset before gradually bringing the system back online!

Optimize the oil circuit: low-level tank → pump → high-level tank → compressor → low-level tank. A tank should be installed at a higher elevation, and the pressure generated by the height of this tank must be sufficient to enable the compressor to operate properly. The volume in the high-level fuel tank must be sufficient to enable the backup pump to start automatically and transfer fuel from the low-level fuel tank to the high-level one.

This post was last edited by nihaocarter on 2018-7-3 08:11. The function of the high-level fuel tank is to ensure lubrication during the shutdown of the engine; it’s not meant to detect low lubricant pressure in order to prevent shutdown. With such a setup, if there is a fault with the oil pump, the pressure will remain normal, but once the level in the high-level fuel tank drops, the pressure will decrease and this will lead to shutdown

I agree with your explanation regarding the role of the high-level fuel tank, but I believe it does not prevent the use of the high-level fuel tank to optimize interlocks. To ensure the reliability and availability of interlocking. Regarding the issue of pump failure you mentioned, it can be incorporated into the interlock logic: if both pumps stop operating simultaneously for more than 10 seconds, the system should also shut down. Furthermore, the vehicle should stop when the fuel tank level is empty; however, stopping does not occur when the tank level is low. Generally, high-level fuel tanks are of the horizontal tank type, with a diameter of no more than 1 meter, and the pressure drop resulting from a decrease in the liquid level is only around 10+kPa. The height of the high-position fuel tank is generally over 6 meters. Specifically, you can refer to the actual applications of upper pressure.

Your suggestion is good, but is there any way to use it like that?

As you are aware, high-position fuel tanks are not uncommon; they are usually located at a height of 6-10 meters, though this naturally depends on the specific conditions at the site. The screw compressors produced by Shanghai Compressor Factory generally come equipped with a high-level oil tank. Furthermore, to determine whether the use of a high-level oil tank to optimize interlocks is suitable for one’s own facility, actual calculations are first required: ① The pressure generated by the liquid level at the bottom of the high-level oil tank must be greater than the oil pressure interlock value. ②The capacity of the high-level fuel tank must be > the cumulative fuel consumption over a certain period during normal operation. Secondly, the interlock system needs to be improved by adding the following: ① The pumps should stop after 10 seconds; otherwise, the system should shut down (this time period is not necessarily fixed at 10 seconds – it depends on the capacity of the fuel tank, but there must be some delay). Additionally, if the oil level in the upper fuel tank is low, an alarm should be triggered to alert the operator to start the pumps temporarily in order to refill the upper fuel tank.