How to prevent reciprocating machine piston rod breakage in advance (recommended)
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In our company, the piston rod of a hydrogen compressor broke at the pressure head, which in turn caused the crankcase to crack, almost leading to a serious accident. Let’s discuss how such accidents can be avoided in advance. I’ll start by suggesting two points: 1. Regular non-destructive testing at all stress concentration areas of the piston rods. 2. During installation, strictly follow the specifications in the design and manufacturing drawings; if significant deviations occur, conduct timely inspections and analyses. 3. Add an online status monitoring system. This post was last edited by yuhan_xu on 2008-7-3 19:51]
Also, it’s necessary to replace them regularly. Additionally, it seems quite difficult to monitor their online status; if anyone has such a system, please share it so that we can all learn from it. :lol
A broken piston rod usually comes with warning signs; the compressor will emit abnormal noises. Reasons such as loose piston nuts or excessive clearance in the crosshead, which causes the piston rod to vibrate, can all lead to such noises. Regular inspections should be intensified; any abnormal noises must have their causes identified, and the defects resolved, to ensure that the system does not operate with faults.
I think it should be as follows: 1. First, use products of high quality; if possible, opt for imported piston rods from abroad. 2. Strengthen the inspection efforts to detect any abnormal phenomena or sounds promptly. 3. Conduct regular checks and replacements
1. Carry out major, medium, and minor repairs on the equipment as planned, conduct flaw detection on the moving parts, and ensure that the clearances at all friction points meet the specified requirements. 2. Strengthen the inspections by operators; such accidents should be preceded by abnormal noises. 3. Strictly control the quality of incoming spare parts.
1. First, take preventive measures by strictly controlling the quality of the spare parts used, including their material, specifications, and manufacturer. 2. Conduct regular monitoring of the equipment’s operation, enhance inspection activities, and identify the root causes of any issues that may arise, striving to address them before they can develop further. 3. While carrying out planned maintenance on the equipment, perform non-destructive testing on those components where stress concentration is likely to occur. 4. Strengthen the inspection process for the equipment and improve the skills of operators in terms of operation and maintenance
Product quality is extremely important, especially the quality of heat treatment and surface processing of the product. Additionally, it would be better if structural improvements could be made.
During installation, the piston rod must be handled in accordance with the technical requirements (instructions) and step-by-step procedures when under pressure; proper heat treatment of the piston rod is essential, and the composition and microstructure of piston rod samples should be checked regularly to prevent problems before they occur.
Why can’t a lock be added to the piston rod? It’s actually quite easy to do that! The effect is also very good, especially when used in hydrogen presses. Our factory has examples of accidents being prevented through the use of chains
The new online condition monitoring system I have installed is RPA system from Halberg Company. It is primarily used to monitor the amount of downward movement of the piston rod, that is, the remaining wear of the piston rings. However, it also has an auxiliary function that allows it to detect the radial movement of the piston rod, which can be used to identify issues such as increased clearance in the crosshead, loose connections of the piston, loose connections of the piston rod, and improper alignment between the piston and the cylinder. It is being used for the first time in the country, and there are still no comprehensive in-depth study materials available.
A broken piston rod usually comes with warning signs; the compressor will emit abnormal noises. Reasons such as loose piston nuts or excessive clearance in the crosshead, which causes the piston rod to vibrate, can all lead to such noises. Regular inspections should be intensified; any abnormal noises must have their causes identified, and the defects resolved, to ensure that the system does not operate with faults. Carry out major, medium, and minor repairs to the equipment as planned, conduct flaw detection on the moving parts, and ensure that the clearances at all friction points meet the specified requirements. Perform non-destructive testing on components with stress concentrations ； Strengthen the inspections by operators; such accidents should be preceded by abnormal noises. Strictly control the quality of incoming spare parts. Strengthen the inspection of equipment and improve the operational and maintenance skills of operators
Measures to avoid accidents caused by broken compressor piston rods: 1. First and foremost, it is necessary to choose high-quality products with reliable performance, as this is the foundation for ensuring proper operation； 2. Install the equipment correctly in accordance with the requirements of the product manual; conduct flaw detection on the important components, and ensure that the clearance of the bearing shells meets the specified requirements. Strict inspection; no abnormalities during trial operation ； 3. Strictly ensure the quality of spare parts; their specifications, materials, geometric dimensions, and tolerances must be consistent with those of the original parts ； It is best to choose original factory parts ； 4. Carry out major, medium, and minor equipment repairs strictly in accordance with the plan. Pay attention to regular maintenance ； Follow proper procedures, strengthen inspections, and promptly investigate any abnormalities to nip accidents in the bud ；
Strictly carry out level 1, level 2, and level 3 maintenance for such equipment. This is described in detail in the Chemical Machinery Maintenance Manual (Volume 2).
The piston rod of your unit that has fractured is of a pressurization-type structure; I believe the causes of this fracture should be analyzed from the following aspects: First, whether the pressurization was carried out in accordance with technical requirements, such as the number of pressurization cycles and whether there are any high points at the joints. II. Is the operating time of the piston rod too long, and has the elastic part of the piston rod exceeded its stretching range, resulting in insufficient pre-tightening force? III. The machining quality of the piston rod, with a focus on whether there are any issues with the heat treatment. IV. Whether the compressor is operating under overload for a long time. V. Are there any defects such as cracks on the surface of the fracture that have not been removed in a timely manner?
Once a compressor accident occurs, there is almost no way to fix it.