The full name of the air compressor is the air compressor; a twin-screw (also known as the Yin and Yang rotor) rotation of the gas volume changes designed according to the working principle of the machine, it can breathe natural air through again.

部几道过程完成工作，终排出满足压力要求的压缩空气，此机器谓螺杄式空气压缩机。

Several processes complete the work, and eventually discharge to meet the pressure requirements of compressed air, this machine is called screw air compressor.

空压机的工作压力压力单位的表示形式很多，这里主要介绍螺杆式空气压缩机常用的压力表示单位；

There are many expressions of the working pressure units of the air compressor. This paper mainly introduces the commonly used pressure gauge units of the screw air compressor.

1．工作压力，国内用户常称排气压力。工作压力是指空压机排出气体的压力；

1. working pressure, domestic users often call exhaust pressure. Working pressure refers to the highest pressure of air discharged from the air compressor.

2．常用的工作压力单位为：bar或Mpa，1bar＝0．1Mpa；

2. the usual working pressure units are bar or Mpa, 1bar = 0.1Mpa;

3．一般性，用户通常把压力单位称为：Kg（公斤），1bar＝1Kg。空压机的容积流量

3. generally speaking, users usually call the pressure unit Kg (kg), 1bar = 1Kg. Volumetric flow rate of air compressor

①容积流量，国内用户常称排气量。容积流量是指在所要求的排气压力下，空压机単位时间内排出的气体容积，折算到进气状态的量

Volume flow is often referred to by domestic users. Volume flow refers to the volume of gas discharged from an air compressor within the required exhaust pressure and converted to the intake state.

②容积流量单位为：m3／min（立方／分钟）或L／min（升／分钟），1m3（立方）＝1000L（升）

(2) Volume flow unit: m3 / min (cubic / minute) or L / min (liter / minute), 1 m3 (cubic) = 1000L (liter)

③一般性，常用的流量单位为：m3／min（立方／分钟）；

(3) general and commonly used flow units are m3 / min (Li Fang / min).

空压机的选型指南

Guide for selection of air compressors

工作压力（排气压力）的选型：当用户准备选购空压机时，要确定用气端所需要的工作压力，加上1－2bar的余量，再选择空压机的压力，（

Selection of Working Pressure (Exhaust Pressure): When the user is ready to purchase air compressor, first of all to determine the working pressure required by the gas end, plus 1-2 bar margin, and then choose the pressure of the air compressor, (

该余量是考虑从空压机安装地点到实际用气端管路距离的压力损失，根据距离的长短在1－2bar之间适当考虑压力余量）。当然，管路通径的大小

The allowance is to consider the pressure loss from the installation site of the air compressor to the actual gas pipeline distance, according to the length of the distance between 1-2 bar to consider the pressure allowance. Of course, the size of the pipe path.

和转穹点的多少也是影响压力损失的因素，管路通径越大且转弯点越少，则压力损失越小；反之，则压力损失就越大。因此，当空压机与各用气

The larger the pipe diameter and the fewer the turning points, the smaller the pressure loss; otherwise, the greater the pressure loss. Therefore, when air compressor and gas are used,

端管路之间距离太远时，应适当放大主管路的通径。如果环境条件符合空压机的安装要求且工况允许的话，可在用气端就近安装

When the distance between ends of the pipeline is too far away, the diameter of the main path should be properly enlarged. If the environmental conditions conform to the installation requirements of the air compressor and the conditions permit, it can be installed near the gas end.

容积流量的选型

Selection of volume flow rate

①在选择空压机容积流时，应先了解所有的用气设备的容积流?，把流的总数乘以1．2（放大20％余量）

(1) When choosing the volume flow of air compressor, we should know the volume flow of all the gas-using equipment first, multiply the total number of the flow by 1.2 (enlarging the 20% allowance).

②新项目上马可根据设计院提供的流量值进行选型

2. The new project can be selected according to the flow rate provided by the design institute.

③向用气设备供应商了解用气设备的容积流?参数进行选型；

(3) to understand the volumetric flow parameters of the gas consuming equipment for the gas supplier.

④空压机站改造可参考原来参数值结合实际用气情况进行选型：合适的选型，对用户本身和空压机设备都有益处，选型过大浪费，选型过小可能

(4) Air compressor station transformation can refer to the original parameters combined with actual gas use to select the type: the appropriate selection, the user and air compressor equipment are beneficial, selection is too wasteful, selection may be too small.

造成空压机长期处于加載状态或用气不够或压力打不上去等弊端。

Causes the air compressor to be in the loading condition for a long time or does not use the gas enough or the pressure cannot hit up and so on malpractices.

功率与工作压力、容积流量三者之间的关系在功率不变的情況下，当转速发生变化时，容积流量和工作压力也相应发生变化；例如：一台22KW的

The relationship between power, working pressure and volumetric flow is constant. When the rotational speed changes, the volumetric flow and working pressure also change accordingly; for example, a 22KW one

空压机，在制造时确定工作压力为7bar，根据压缩机主机技术曲线计算转速，排气量为3．8m3／min；当确定工作压力为8bar时，转速必须降低（

The working pressure of the air compressor is determined to be 7 bar at the time of manufacture, and the rotational speed is calculated according to the technical curve of the compressor main engine. The exhaust capacity is 3.8 m3/min. When the working pressure is determined to be 8 bar, the rotational speed must be reduced.

否贝驱动电机会超负荷），这时，排气量为3．6m3／min；因为，转速降低了，排气也相应减少了，依此类推功率的选型是在满足工作压力和容积

Whether the motor will be overloaded, then the exhaust capacity is 3.6 m3/min; because the rotational speed is reduced, the exhaust capacity is also reduced, and so on the selection of power is to meet the working pressure and volume.

流量的条件下，供电容量能满足所匹配驱动电机的使用功率即可。

Under the condition of flow, the power supply capacity can meet the power used by the matching driving motor.

因此，选配空压机的步骤是：先确定工作压力，再定相应容积流量，是供电容量

Therefore, the selection of air compressor steps are: first determine the working pressure, then determine the corresponding volume flow, and finally the power supply capacity.