How to lubricate the shaft bearings of the large and small ends in a reciprocating compressor?
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Experts, the lubrication of the big and small end bearing shells is achieved by injecting lubricant through the oil injection hole located in the crosshead pin. But as the crosshead pin moves back and forth with the crosshead, how is it possible to establish a connection between the oil injection tube and the crosshead pin?
The small-head tile has oil grooves, which are used to deliver oil to the side that is not under pressure (the side with a gap)
Isn’t the oil in the oil sump poured in through the oil filling hole in the middle of the crosshead pin?
Oil path (in general, though there are also special cases): oil pump --- crankshaft bore --- big end bearing --- connecting rod bore --- crosshead pin --- small end bearing --- crosshead slider, and finally flows into the crankcase
There are no oil holes on the crankshaft now; the oil is simply injected through the oil holes on the side of the rod boss pin
The oil path starts from the crosshead slider, passes through the small-end bearing, then goes through the rod oil hole to reach the large-end bearing
Didn’t the oil in the slip ring leak out? Can such great pressure reach the large tile?
The special case is when the oil path is reversed
There are two scenarios: in domestic products, it is usually from the crankshaft to the slip ring, while in foreign products it is from the slip ring to the crankshaft
There are differences among different compressor oil circuits. Let me explain the simple L-type circuit: the oil starts from the primary filter in the oil sump, goes to the oil cooler, then to the gear oil pump and the secondary filter; from there it passes through the crankshaft’s central hole to the big end bearings, then via the connecting rods to the small copper sleeves, onto the crosshead pins, and finally to the crosshead, before returning to the oil sump.