Difference, Selection and Application of Screw Compressor and Centrifugal Compressor

Release time：2026-03-25    Click：4

　　Difference, Selection and Application of Screw Compressor and Centrifugal Compressor？Screw compressor and centrifugal compressor are two core equipments that occupy the mainstream. Although they are both gas compression devices, they are essentially different in working principle, structural characteristics, energy consumption performance and applicable working conditions, which directly determine the project selection, operation and maintenance cost and long-term operation stability. If you want to accurately match the production demand, you must thoroughly understand the core characteristics of the two types of compressors and avoid the misunderstanding of selection.

　　Turbo-Tech introduces the difference, selection and application between screw compressor and centrifugal compressor.

　　First, the working principle difference

　　1. Working principle of screw compressor

　　Screw compressor is a typical positive displacement compressor, and its core depends on a pair of male and female screw rotors which are engaged with each other precisely to do work. During the operation, the rotor rotates to form a closed cavity, and the gas is gradually sucked into the cavity. As the meshing gap of the rotor continues to shrink, the gas volume is forcibly compressed, and the pressure continues to rise, and then it is discharged from the exhaust port.

　　This compression mode belongs to intermittent air intake and continuous exhaust, and the gas is in direct contact with the rotor, which requires extremely high machining accuracy and material wear resistance of the rotor. Thanks to the characteristics of volume compression, the pressure ratio of screw compressor is controllable, which can easily adapt to medium and high pressure conditions, and the pressure fluctuation is minimal when operating under variable conditions.

　　2. Working principle of centrifugal compressor

　　Centrifugal compressor belongs to power (speed) compressor, and its core components are high-speed impeller, diffuser and volute. When working, the motor drives the impeller to rotate at high speed (the rotation speed can reach tens of thousands of revolutions per minute), and the gas is accelerated to be sucked by centrifugal force, and the gas obtains strong kinetic energy in the impeller, and then enters the diffuser to decelerate and pressurize, thus completing the conversion from kinetic energy to pressure energy, and then stably outputs through the volute.

　　This mode is full continuous air flow, with no direct contact between gas and core components, no mechanical friction loss, and the exhaust capacity of a single machine far exceeds that of a screw machine, which is suitable for the scene of super-large flow and continuous and stable air supply, and the high-pressure working condition needs to be realized in series in multiple stages.

　　Two, screw compressor and centrifugal compressor selection decision guide

　　The selection of screw compressor or centrifugal compressor should be based on the following key considerations:

　　1. Priority is given to the scenario of screw compressor:

　　Small flow demand;

　　Pressure demand is changeable or load fluctuates frequently;

　　The initial budget is limited;

　　The gas is allowed to contain oil or the medium is special;

　　High maintenance convenience and lack of experienced maintenance team;

　　2. Prefer the scenario of centrifugal compressor:

　　Large flow demand (single machine ≥20m3/min);

　　Continuous and stable operation, long-term full load condition;

　　Strict requirements for gas purity (no oil);

　　Space is limited and compact equipment layout is needed;

　　Life cycle cost optimization, can accept higher budget;

　　Three, two kinds of compressor scene application

　　1. Optimal scenario of screw compressor

　　-Small and medium-sized industrial gas: in the scenes of large flow fluctuation and stable pressure requirements such as food processing, pharmacy, textile and automobile parts manufacturing, the variable frequency screw machine can accurately adapt to load changes, saving energy and reducing consumption.

　　-Space-limited projects: compact workshop, mobile gas scene, small size of screw machine, convenient installation and flexible layout.

　　-Off-design operation scenario: projects with fluctuating gas load day and night and seasonal adjustment rely on excellent partial load energy efficiency to avoid energy waste.

　　2. Optimum selection scenario of centrifugal compressor

　　-Large-scale industrial centralized gas supply: petrochemical industry, iron and steel smelting, air separation, power plants, etc., which require super-large-flow, continuous, stable and pulse-free compressed air.

　　-Oil-free pure gas use scenario: electronic chip, precision manufacturing, aseptic production of medicine, centrifugal compressor without lubricating oil contact, gas without oil pollution, and extremely high purity.

　　-Long-term continuous operation project: 24-hour uninterrupted production line, long service life of centrifugal compressor and lower long-term operation and maintenance cost.

　　The above is an introduction to the difference, selection and application of screw compressor and centrifugal compressor. Screw compressor is the first choice for small flow and variable working conditions. Centrifugal compressor wins in large flow, high efficiency and long life, and it is the core equipment of large-scale continuous gas project. The actual selection can be entrusted to manufacturers such as Turbo-Tech to calculate the working conditions, and customize the scheme according to the site layout and energy consumption budget.