I have a question from the experts regarding the testing of a reciprocating compressor after removing one piston (Urgent)
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I would like to ask the experts: For a reciprocating compressor with 3 stages and 4 cylinders, if maintenance is taken into consideration, is it possible to remove one of the pistons and address issues such as the oil scrapper ring and packing? If the leakage is within acceptable levels, only 3 cylinders will be in operation; in that case, only the crosshead will move when that stage is removed. How much of an impact does this have on its overall balance? How great is the risk?
The required pressure should not be sufficient; it’s unclear why such a risky approach was taken. .
When the balance is disrupted, the reverse angle may change. It may cause the crosshead to sinter
Four columns with three stages: generally, there are two first-stage cylinders, one second-stage cylinder, and one third-stage cylinder; usually, the two first-stage cylinders share a buffer tank. No matter which one is removed, gas will leak in large amounts and the compressor will not be able to operate.
It’s absolutely not allowed! Reciprocating compressors are designed with full consideration given to the piston forces, gas forces, and inertial forces at each stage; any modifications should be carried out under the guidance of the manufacturer or a qualified modification facility, as doing so on-site can easily lead to production accidents.
I’ve seen a Dresser-Rand reciprocating compressor where only the 4th stage had a crosshead for operation; there was no cylinder block.
That is a virtual cylinder, used to balance piston forces
The manufacturer must recalculate it! You can’t make decisions on your own.
This post was last edited by space ★ Xuan on 2016-10-22 08:13. A cylinder that lacks a true cylinder structure is generally referred to as a fake cylinder; it is used to balance the inertial forces resulting from the rotation of the crankshaft (it can also be said to serve to balance the combined forces exerted by the pistons). Fake cylinders are usually installed on one side of the high-pressure cylinders – for example, in a four-row, three-stage compression system, one of those cylinders is fake. Typically, the fake cylinder and the third stage are on one side, while the first and second stages are on the other side. Gas force and pressure ratio are related to factors such as intake pressure and piston area; by designing the forces at the third stage and the first and second stages, a relative balance can be achieved. But inertial force is different; at a constant operating speed, inertial force is related to mass. On one side is the mass of two connecting rod crosshead pistons, while on the other side it is one. All inertial forces are severely mismatched, so a fake cylinder was added to balance them out. The poster’s question is clearly answered here: it is not possible to remove one stage. The dynamic balance of a reciprocating compressor is determined based on design values, with various forces acting together to create a stable state; removing one piston changes the gas forces as well as the inertia forces associated with mass. Once either of these elements is altered, the designed balance is disrupted. There may be issues such as high starting torque that prevents startup, or excessive vibration that makes operation impossible. If startup is possible, the process parameters might meet the required standards; however, excessive stress in certain areas could lead to fractures and permanent damage to the equipment.
It’s not possible. If you’re not afraid of the vehicle getting written off, you can give it a try