主要适用于机车车辆上用来测量液压系统或储气缸的压力；亦可用于对铜合金钎焊无腐蚀性，非结品和凝固的种介质的压力测量。 The double needle pressure gauge is mainly suitable for measuring the pressure of hydraulic systems or storage cylinders on rolling stock; it can also be used for non-corrosive, non-structural and solidified medium pressure measurement of copper alloy brazing. The meter can simultaneously measure two pressures which are the same or different (the difference between the two should generally not be greater than 1/3 of the limit value on the scale range). The structure principle of the double needle pressure gauge is composed of two independent measuring systems and indicating devices. The working principle of the meter is based on the elastic deformation of the elastic element (spring tube in the measurement system). That is, under the action of the measured pressure, the ends of the two spring tubes are respectively caused to have corresponding displacements. With the help of the pull rod, they are driven by the gear transmission mechanism and enlarged. The red and black pointers on the fixed gear shaft chase the two The measured values are indicated on the dials respectively;
的质量1. 一般压力表的弹簧管是具有一定横截面形状( 常用的有扁平圆和近似椭圆形两种) ，弯曲成“C” 形，而且能满足一定弹性要求的管状弹簧。 Choosing the quality of a two-needle pressure gauge 1. The spring tube of a general pressure gauge is a tube with a certain cross-sectional shape (usually a flat circle and an approximately oval shape) that is bent into a "C" shape and can meet certain elastic requirements. spring. If the spring tube is too small, it will affect the accuracy level of the pressure gauge. 2. The indication of the pressure gauge exceeds the allowable error, the indication adjustment screw of the gauge should be adjusted. If the gauge does not have the indication adjustment screw, the gauge can only be judged as unqualified. 3. The dial numbers and symbols of the pressure gauge dial shall be complete and clear. The dial indexing scales should be evenly distributed, and the center angle of the package is generally 270 °. The pointer of the pressure gauge should extend into all the indexing lines. The width of the pointer indicating end should not be greater than 1/5 of the minimum indexing interval. The distance between the pointer and the plane of the index plate should be within the range of 1 to 3mm. If the outer diameter of the case is above 200mm (including 200mm), the distance between the pointer and the plane of the index plate should be within the range of 2 to 4mm. 4. For a pressure gauge with a stop pin, the pointer should be close to the stop pin when there is no pressure or vacuum, and the "shrinkage" must not exceed the specified allowable error. 5. The case of the pressure gauge should be able to protect the internal parts from contamination. The pressure gauge should be equipped with a safety hole. The safety hole must be equipped with a dustproof device. 6. Digital pressure gauge. It depends on the rationality of the overall structure, the selected material, the aging process of the electronic components, and long-term stability.
Five pressure gauge installation
的安装1. 双针压力表的安装位置应符合安装状态的要求，表盘一般不应水平放置，安装位置的高低应便于工作人员观测。 Installation of the double needle pressure gauge 1. The installation position of the double needle pressure gauge should meet the requirements of the installation state. The dial should generally not be placed horizontally, and the height of the installation position should be easy for staff to observe. 2. The distance between the installation point of the two-needle pressure gauge and the pressure measuring point should be as short as possible, to ensure perfect sealing and no leakage. 3. The two-needle pressure gauge should have a buffer at the front of the installed pressure gauge; for easy inspection A shut-off valve should be installed under the meter; when the medium is dirty or there is pulse pressure, filters, buffers and pressure regulators can be used.