Techniques And Key Points for Controlling The Clearance of Sealing Rings in Reciprocating Compressors

Techniques and key points for controlling the clearance of sealing rings in reciprocating compressors

In industrial production, reciprocating compressors are one of the core equipment, and the precise control of the sealing ring clearance plays a crucial role in ensuring the efficient operation of the equipment, extending its service life, and ensuring the stability of the production process. Today, let's delve into the key points and practical techniques for controlling the clearance of the sealing ring in reciprocating compressors.

1. The importance of sealing ring clearance

The gap between the sealing ring and the piston rod, sealing box, and other components during installation and operation refers to the small space formed between the sealing ring and these components. A reasonable gap can effectively prevent gas leakage and ensure the sealing performance of the compressor. If the gap is too large, it will increase gas leakage, reduce the compression efficiency of the compressor, and may even cause safety hazards; If the gap is too small, it will increase the friction between the sealing ring and the piston rod, increase energy consumption and wear, and may also cause the sealing ring to get stuck, leading to premature seal failure.

2. Control method for sealing ring gap

2.1. Reasonable selection of sealing ring materials is the basis for controlling clearances. Common sealing ring materials include cast iron, cast steel, explosion-proof alloys, etc. Different materials have different coefficients of thermal expansion and elastic moduli. When selecting materials, it is necessary to comprehensively consider factors such as the working temperature and pressure of the compressor to reduce the gap changes caused by thermal expansion.

2.2. The machining accuracy of the sealing ring directly affects the size of the gap. During the machining process, it is necessary to strictly control the dimensional accuracy of the outer diameter, inner diameter, thickness, etc. of the sealing ring to ensure that it can meet the required clearance range after assembly. High precision machining can effectively reduce excessive or insufficient gaps caused by dimensional deviations.

2.3. Optimizing the assembly process is a key step in controlling the gap between sealing rings. During the assembly process, the following points should be noted: • Pressing force: When pressing the sealing ring, the force should be moderate. Excessive pressing force will result in a gap that is too small, while insufficient pressing force will lead to a gap that is too large. Installation direction: The installation direction of the sealing ring is also important. In general, the opening of the sealing ring should not be in the same direction as the piston sphere to reduce gas leakage. Axial clearance control: For packing sealing rings, there should be appropriate axial clearance between the two rings in the sealing box, generally controlled by the upper limit at the bottom and the lower limit at the outside.

2.4. During the operation of the compressor, it is necessary to regularly monitor the changes in the clearance between the sealing rings. If the gap is found to exceed the design range, it should be adjusted in a timely manner. For example, the clearance can be fine tuned by adjusting the clamping device of the sealing ring, or replacing severely worn sealing rings.

3.Common problems and solutions

3.1. Leakage caused by excessive clearance. If it is found that the clearance between the sealing ring is too large, resulting in gas leakage, the following measures can be taken:

Check the wear condition: Check the wear condition of the sealing ring and piston rod, and replace the worn parts if necessary.

Adjust the clamping device: Adjust the clamping device of the sealing ring appropriately to reduce the gap.

3.2. If the gap is too small, it may cause the sealing ring to get stuck. At this point, you can:

readjust the gap: loosen the clamping device, readjust the installation position of the sealing ring, and increase the gap. Check thermal expansion:

Check the operating temperature of the compressor to ensure it is within the normal range and avoid gaps that are too small due to thermal expansion.

Controlling the gap between the sealing rings of reciprocating compressors is a systematic project that requires multiple aspects such as material selection, machining accuracy, assembly process, and operation monitoring. By selecting materials reasonably, strictly controlling processing accuracy, optimizing assembly processes, and strengthening operation monitoring and adjustment, the gap between the sealing rings can be effectively controlled, the sealing performance and operating efficiency of the compressor can be improved, and the service life of the equipment can be extended.