论文部分内容阅读
目前,在工厂中对储缸液面显示和控制大多采用浮球、电极、液柱压力、气动、电动差压变送系统等方法。这些方法中各有优缺点。因受各种条件限制,其可靠性、经济性都不大理想。为适应生产的需要,我们采用了简单的空管取压、空气导压配以上海自仪四厂生产的YEJ型膜压计进行显示和控制来测量液面,投入生产使用后效果较好。测量系统原理如图1所示。图中2、3、4组成一封闭的压力测量空腔,当储缸内液面上升时,在取压管内即可产生液柱压力,此压力通过导压管内空气传递到膜压计,即得示值△P=γ(H—h),此值与液值高低有着一定的比例关系,根据玻-马定律得P_1V_1=P_2V_2,可知它与取压管的有效内径、导压管的有效内径和长度等有关。为提高△P值,取
At present, most of the liquid level display and control of the storage tank in the factory adopts methods such as float ball, electrode, liquid column pressure, pneumatic and electric differential pressure transmission system. Each of these methods has its advantages and disadvantages. Due to various conditions, its reliability, economy are not ideal. In order to meet the needs of production, we adopted a simple empty tube take pressure, air pressure with the YIJ-type pressure gauge manufactured by Shanghai Instrument Factory to display and control to measure the liquid level, put into production better after use. Measuring system principle shown in Figure 1. Figure 2, 3, 4 constitute a closed pressure measurement cavity, when the storage tank liquid level rise, the pressure in the pipe can produce liquid column pressure, the pressure through the guide tube air transfer to the membrane pressure gauge, that is The value of △ P = γ (H-h) shows a certain proportional relationship with the liquid level. According to the Bollinger’s Law P_1V_1 = P_2V_2, it can be seen that the effective internal diameter of the take-pressure tube and the pressure guiding tube are effective Inner diameter and length and so on. To improve △ P value, take