Why do reciprocating compressors have unloaders in both stage 1 and stage 2? Four unloading devices in total, two in each section! Why is this? Also, how are the unloading devices in section one and section two adjusted during load addition and reduction?
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Why do reciprocating compressors have unloaders in both stage 1 and stage 2? What is the reason for this? Also, how are the unloading devices in section one and section two adjusted during load addition and reduction? If anyone understands, please explain it
It’s about adding or reducing load, controlling how many load valves are in operation
Is it Action Phase 1 or Phase 2? How do I adjust it? Could you explain it clearly?
Judging from the photo, it should be a double-acting cylinder. The function of the unloading valve is to push open the intake valve, keeping it open in order to regulate the load. Therefore, a typical double-acting cylinder requires at least two unloading valves to push open the inlet valves on the cylinder side and the shaft side respectively. Additionally, each stage of cylinders requires a unloading valve for synchronized adjustment. Therefore, by using a unloading valve to switch the double-acting cylinder on and off, it is possible to adjust the load to three levels: 0 (fully open on both the cylinder side and the shaft side), 50% (one side open on each of the cylinder side and the shaft side), and 100%. (If more precise adjustment is required, it is usually done in conjunction with a backflow control valve or an adjustable clearance cylinder; for higher-end systems, there are options similar to HYDROCOM. ）
When adjusting the load, should it be the first-stage or second-stage unloader that is used?
When adjusting the load, unless intermediate evacuation is used, it is generally adjusted synchronously in stages.
Judging from the photo, do you only have three load settings: 0.50%, 100%? At 0 load, both intake valves in stages 1 and 2 are fully opened ； At 50% load, it is usually the shaft-side air valve that opens ； At a load of 100, all four intake valves are in use. This type is regulated by a push-open suction valve. Your machine doesn’t have adjustment for excess space. To push open the suction valve, both stage 1 and stage 2 need to be pushed open simultaneously. It is not recommended to operate at 50% load for extended periods during normal operation.
What model? Secondary compressor?
Where does the concept of a third stage come from? Moreover, the number of stages isn’t determined by the number of cylinders; these two cylinders are of the same size, and it’s even possible that there is only one stage of compression
The loading is done simultaneously. You’ve only taken photos of the compressor’s body; generally, there is an operation panel on the front side of the body, which shows the primary and secondary pressures, as well as a load switch – the 50% and 100% levels mentioned earlier. After starting the compressor with no load, it runs for a few minutes; if there are no abnormalities, the load is increased to 50%. If there are still no issues such as noises or leaks, the load is increased to 100%
The 4th floor is the correct answer; in fact, if the range of operating conditions doesn’t vary much, it seems to have no practical use. After all, there is no margin adjustment; it still has to be adjusted through the return line.