螺杆压缩机是一种工作容积作回转运动的容积式气体压缩机械。气体的压缩依靠容积的变化来实现，而容积的变化又是借助压缩机的一对转子在机壳内作回转运动来达到。
A screw compressor is a volumetric gas compression machine that operates with a rotating volume. The compression of gas relies on changes in volume, which in turn is achieved by a pair of rotors of the compressor rotating inside the casing.
螺杆空压机基本构造：在压缩机的机体中，平行地配置着一对相互啮合的螺旋形转子，通常把节圆外具有凸齿的转子，称为阳转子或阳螺杆。把节圆内具有凹齿的转子，称为阴转子或阴螺杆，一般阳转子与原动机连接，由阳转子带动阴转子转动转子上的最后一对轴承实现轴向定位，并承受压缩机中的轴向力。转子两端的圆柱滚子轴承使转子实现径向定位，并承受压缩机中的径向力。在压缩机机体的两端，分别开设一定形状和大小的孔口。一个供吸气用，称为进气口;另一个供排气用，称作排气口。
Basic structure of screw air compressor: In the body of the compressor, there is a pair of spiral rotors that mesh with each other in parallel. Usually, the rotors with convex teeth outside the pitch circle are called male rotors or male screws. The rotor with concave teeth inside the pitch circle is called a female rotor or a female screw. Generally, the male rotor is connected to the prime mover, and the male rotor drives the female rotor to rotate the last pair of bearings on the rotor to achieve axial positioning and withstand the axial force in the compressor. The cylindrical roller bearings at both ends of the rotor enable radial positioning of the rotor and withstand radial forces in the compressor. Set up holes of a certain shape and size at both ends of the compressor body. One for inhalation, called an intake port; The other is for exhaust, called the exhaust port.
进气
inlet
螺杆空压机的工作过程详细分析之进气过程：转子转动时，阴阳转子的齿沟空间在转至进气端壁开口时，其空间最大，此时转子齿沟空间与进气口的相通，因在排气时齿沟的气体被完全排出，排气完成时，齿沟处于真空状态，当转至进气口时，外界气体即被吸入，沿轴向进入阴阳转子的齿沟内。当气体充满了整个齿沟时，转子进气侧端面转离机壳进气口，在齿沟的气体即被封闭。
Detailed analysis of the working process of screw air compressor - intake process: When the rotor rotates, the tooth groove space of the male and female rotors is maximized when it turns to the opening of the intake end wall. At this time, the tooth groove space of the rotor is connected to the intake port, because the gas in the tooth groove is completely discharged during exhaust. When the exhaust is completed, the tooth groove is in a vacuum state. When it turns to the intake port, the external gas is sucked in and enters the tooth groove of the male and female rotors along the axial direction. When the gas fills the entire tooth groove, the end face of the rotor inlet side rotates away from the casing inlet, and the gas in the tooth groove is closed.