Issues regarding the design life and service life of the piston rod in reciprocating compressors

No one is paying attention to this issue, so I’ll reply first to prevent it from getting overlooked.

In fact, people don’t pay much attention to the lifespan of piston rods, mainly because they are not aware of the risks involved. Often, damage such as fracture, elongation, wear, and deformation occurs before reaching the end of its service life. However, some piston rods can last for many years thanks to proper use. Only heaven knows when it will break; in any case, if it’s not damaged, keep using it – that’s very dangerous. If it’s used with hazardous substances such as hydrogen, the consequences can be severe.

It seems that the actual situation is as the original poster understands it: unless the company using the compressor is very wealthy, regular preventive maintenance is usually carried out (typically based on the total operating time), and in my case it’s around 10,000 hours of operation in total. Perform a crankshaft rotation test for runout; if the runout value is high, prepare spare parts, wait for them to arrive, pull out the piston rod for inspection, and replace it if necessary. To be honest, wear of the piston rod is inevitable; it is recommended that the original poster pay more attention to the condition of small components such as the nuts used to secure the piston rod. There are many failures related to piston rods; initially, these failures occur because the nuts used to secure the piston rods loosen and fall into the cylinder, which prevents the piston rod from moving through its full range of motion. This leads to significant vibration in the machine, and in many cases, the piston rod even becomes deformed or breaks.

It is recommended to operate for around 16,000 hours, which means it should be replaced after about 2.5 years; color flaw detection should be carried out regularly during maintenance.

I have one here that has been in use for 10 years; I need to convince my supervisor to replace it by providing reasons.

I’ve never heard of piston rod fractures; there has to be a reason for replacing it. If what you say is true, then the crankshaft has also been in use for a long time – wouldn’t it be dangerous if it wasn’t replaced as well? During major overhauls, these components can be colored and ultrasonically inspected, which is sufficient. The component doesn’t deform or wear out; apart from the high cost, I can think of no reason to replace it. On the other hand, the connecting rod screws and the spindle bearing screws can be replaced.

During maintenance, check if the wear is severe; if so, it needs to be replaced. The tolerance allowed is 2 units. You can purchase tungsten carbide piston rods, which have a longer service life. Our company specializes in compressors, and we use tungsten carbide rods – their lifespan is several times that of ordinary piston rods. Contact me at 13898892992 if you want tungsten carbide piston rods. We also offer services for restoring crankshafts to their original dimensions as well as compressor modifications

During maintenance, check if the wear is severe; if so, it needs to be replaced. The tolerance allowed is 2 units. You can purchase tungsten carbide piston rods, which have a longer service life. Our company specializes in compressors, and we use tungsten carbide rods – their lifespan is several times that of ordinary piston rods. Contact me at 13898892992 if you want tungsten carbide piston rods. We also offer services for restoring crankshafts to their original dimensions as well as compressor modifications

It’s not a matter of money; the safety responsibility is significant. My skills might not be up to par; I’ve had cases where the piston rod and connecting rod bolts broke. I think whether the service life of the piston rod should be designed based on fatigue life?

The main factor is whether the manufacturer of the accessories is reliable; secondly, inspections are carried out during maintenance – it’s not true that replacing them with new ones necessarily ensures safety. I’ve been using my domestic one for over a decade, and the imported one for over thirty years. Those of us who are in equipment management need to base everything on solid evidence; it’s not enough to simply say “I think.” Of course, this becomes very useful once you become a manager.