The crosshead slider is damaged; can it still be used after sanding?
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The crankshaft bearings were replaced, and after the machine was operated at full load for 144 hours, it was stopped for inspection – everything appeared normal. It was then operated again for another 175 hours, during which iron particles in the oil were detected through the observation port. Upon stopping the machine, it was found that both the piston crown and the slider were abraded. The cause of this failure is believed to be a alignment issue; measurements taken with a wire showed that the alignment was more or less correct. Unfortunately, there was no infrared alignment device, nor any measuring tools such as feelers, so the clearance between the piston crown and the slider could not be determined. Today, the piston ring guides, guide rings, and packing were replaced. I would like to ask the experts here: can this slider still be used after being polished with sandpaper?
1. The clearance between the slide and the crosshead should be appropriate; if the contact area, as measured using red lead powder, is greater than 70%, then it can be used. If not, grinding is required. 2. It is necessary to find out the reasons: whether there are any scratches on the cylinder, the degree of ellipticity of the cylinder, the play in the piston rod, and whether the coaxiality between the crosshead slide and the cylinder is within the standard range. 3. A personal question: logically, it should be the crosshead slide that wears out first in case of wear. Has the babbitt metal been completely worn away? It’s best to show an image
Alas, this is all the cost that companies have to bear in order to build up their own maintenance capabilities :) Getting the equipment installed to this level is definitely not something that can be resolved just by using the Internet. There aren’t even the most basic plug gauges available for maintaining such equipment,,, Stop playing around with it – if you keep doing that, it will get damaged. It is recommended to replace this tile as soon as possible.
Are the bearings of different sizes? Has the center height changed? ? Did the crosshead move during maintenance? It’s not installed backwards, is it?
It’s not for companies to train maintenance personnel. . . Everyone wants a piece of the big pie represented by listed companies. The accessories are expensive and of poor quality, and it’s common for them not to arrive on time. The annual budget for May has already been exhausted; replacing them isn’t that simple. It’s extremely difficult to find a solution that allows us to continue using those accessories without having to replace them.
The cylinder surface is smooth; I don’t know the internal cylinder data without a dial indicator. It seems that the piston is shaking a lot. I just replaced the guide rings and piston rings as well as polished the packing – let’s see what happens. This L-type air compressor has no alloy layer on either the crosshead or the slider; there is direct iron-to-iron contact.
With a micrometer, it is possible to measure ellipticity. . . Use a level to check the levelness of the cylinder, referring to the SH reciprocating compressor maintenance standards
There are no micrometers or levelers; the only measuring tools available are a tape measure and a vernier caliper. The repair and assembly work was completed today, and testing will take place after the supervisor signs off. This compressor has experienced issues such as broken piston rings, collisions with the cylinder head, and bent connecting rods. After replacing the connecting rods, it operated for 3000 hours; in April, the crankshaft began to loosen, causing vibration that wouldn’t stop. There were also problems with worn bearings and sliding plates – it was really frustrating.
Is this a state-owned enterprise? . . . State-owned enterprises won’t let you drive like this. .
It is a privately-owned listed company, not a state-owned enterprise. This company has no systems at all; after each maintenance task, I prepare written documents and send them to the relevant authorities to avoid taking blame.
Good luck to you, brother. If you get the chance, change jobs