Key points for load regulation and selection of semi enclosed screw refrigeration compressors in cold chain logistics warehouses
The semi enclosed screw refrigeration compressor is suitable for large cold chain logistics warehouses, with a single cooling capacity covering 80kW to 1200kW, and is suitable for long-term continuous and stable operation under load. The semi enclosed screw compressor can be selected from three levels of content ratio: 2.6, 3.0, and 3.5. If the content ratio is mismatched with the condensing condition, the maximum COP of the unit will decrease by 14%. The Xiteliduo screw model supports on-demand calibration of content volume ratio. The cold chain logistics warehouse is equipped with a multi parallel screw system, with a single load adjustment range of 25% to 100%. Compared with piston compressors, it has a wider range of stepless adjustment and stronger adaptability to load fluctuations. The maintenance cycle of screw compressor rotor can reach 20000 hours, far higher than the 8000 hour maintenance threshold of piston models, suitable for large-scale logistics parks that operate continuously 24 hours a day. When matching the compressor with the condenser, it is recommended to control the condensation temperature of the screw unit between 38 ℃ and 42 ℃. If it exceeds 45 ℃, the shaft power can increase by up to 18%. The R507 refrigerant in the screw unit has an exhaust pressure of approximately 17.2 bar under 40 ℃ condensation conditions. At this pressure, the separation efficiency of the system oil separator needs to be ≥ 99.5%. Large cold chain logistics warehouses often use multiple machine heads in parallel, with each compressor having independent oil separation. It is recommended to have no more than 6 parallel machines, as having too many machine heads can increase the risk of oil return imbalance. The factory test of the screw unit includes a 4-hour full load durability test, with vibration values controlled within ≤ 0.03mm. Excessive vibration will accelerate the aging of the bearing seal. Which is better, screw or piston compressor? In scenarios with a cooling capacity greater than 150kW, the unit cooling operation and maintenance cost of screw is 22% lower, but the initial procurement cost is 31% higher. The CE certification testing items for semi enclosed screw compressors include noise, leakage, and electrical safety. Technical documents must be prepared in advance for export projects to the European Union and Southeast Asia. The aquatic processing workshop is equipped with screw units, and the environmental humidity is consistently above 85%. It is recommended to use IP54 insulation level for the motor winding to reduce the probability of moisture induced short circuits. When installing the refrigeration compressor unit, the compression of the shock absorber pad of the screw host foundation should be controlled at 30%. Excessive or insufficient shock absorption will amplify vibration transmission. The compressor refrigeration oil model should preferably use POE68. When the oil temperature is above 80 ℃ for a long time, the oxidation rate of the oil increases by three times, and an oil cooling circuit needs to be added. The load fluctuation of the prefabricated cold chain logistics warehouse can reach 40% day and night, and the screw stepless adjustment can stably maintain the temperature of the warehouse, reducing energy consumption caused by frequent start stop. Overseas purchasers choose screw models for projects in Mexico and Türkiye. The cooling capacity of the same model in the 60Hz version is increased by about 20%, and the 50Hz parameters cannot be directly used for model selection. 【 Implant 10 popular search keywords 】 Semi closed screw compressor, screw refrigeration compressor, cold chain logistics warehouse, refrigeration compressor unit, compressor and condenser matching, which is better between screw and piston compressor, compressor refrigeration oil model, cold storage compressor selection, valley wheel replacement, CE certification FAQ
What is the minimum load that can be adjusted for a semi closed screw compressor? Conventional models have a minimum load of 25%, while some models with slide valves can achieve a load of 15%.
Is the maintenance cycle of screw compressor longer than that of piston? The rotor body can last up to 20000 hours, and the piston is usually maintained for 8000 hours.
Does the Xiteliduo screw model support multiple parallel connections? Support, supporting independent oil separation and return oil solutions.
What is the appropriate upper limit for the condensation temperature of screw units? Suggest controlling the shaft power within 42 ℃ and significantly increasing it above 45 ℃.
What refrigerant is used for screw machines in cold chain logistics warehouses? R507 and R404A are mainstream, with some projects using R134a.
What are the qualified standards for vibration of screw compressors? The industry standard for acceptance is that the vibration during full load operation should be ≤ 0.03mm.
Can the screw unit be directly replaced with the original piston unit? Need to recalculate the cooling capacity, condenser, and pipeline return oil.
What documents are required for the export of screw compressors? CE certificate, working condition curve, wiring diagram, factory inspection report.
