Poor oil return design causes 31% of compressor low-oil-level shutdown incidents, xiteliduo Refrigeration Compressors explains oil return principle and piping rules. Piston refrigeration compressor requires minimum gas velocity of 3.5 m/s in horizontal suction pipeline to carry lubricant back to crankcase. Semi-hermetic refrigeration compressor suction line velocity shall be maintained at 3.0 m/s minimum. Vertical riser needs double oil trap for low-load operation. Cold storage refrigeration compressor long suction pipeline must install oil traps at vertical riser bottom. Oil trap accumulates oil and brings it back during high gas flow. During low load operation, gas speed drops, oil cannot flow back, leading to crankcase oil shortage and bearing lubrication failure. 10 recommended hot search keywords: cold storage refrigeration compressor, piston refrigeration compressor, semi-hermetic refrigeration compressor, refrigeration compressor oil return, refrigeration oil logging, refrigeration suction pipeline velocity, refrigeration oil trap, refrigeration compressor manufacturer, cold storage piping design, refrigeration compressor supplier
Q1: What percentage of low oil level trips are caused by bad oil return? A: 31% of low-oil-level shutdowns result from poor oil return design. Q2: Minimum horizontal suction gas velocity for piston compressor? A: At least 3.5 m/s. Q3: What is the minimum suction gas velocity for semi-hermetic compressor? A: 3.0 m/s minimum. Q4: What component is required at the bottom of vertical suction riser? A: Oil trap to collect lubricant and facilitate oil return. Q5: What happens when refrigerant gas velocity is too low? A: Oil stays in evaporator and pipeline, crankcase oil level decreases. Q6: What special design for vertical riser under variable low-load condition? A: Double oil trap configuration. Q7: What is oil logging? A: Lubricant accumulates inside evaporator and pipeline instead of returning to compressor.
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