差压式液位计用于氨罐液位的精确测量  

Differential Pressure Level Gauge Used for Accurate Measurement of Ammonia Tank Level

作　　者：胡乃清 俞慎泉 HU Nai-qing;YU Shen-quan(Sichuan Vocational College of Chemical Technical,Luzhou 646000 China)

机构地区：[1]四川化工职业技术学院,四川泸州646000

出　　处：《自动化技术与应用》2020年第3期140-142,共3页Techniques of Automation and Applications

摘　　要：针对法兰式差压液位计在氨罐液位测量过程中,存在液氨密度受温度、压力的影响所带来测量误差,在分析误差产生的原因后,提出线性插值法进行温度补偿的解决办法。在此基础上,利用集散控制系统软件提供的二维折线表,首先实现密度-温度的分段线性处理,在准确求出液氨密度后,进一步利用液位-密度之间的关系算出氨罐液位.经调试运行,此测量方案在液氨测量过程中,在不增加成本的前提下,具有测量精度高、响应速度快、可靠性高、经济性好等优点。In view of the measurement error caused by the influence of temperature and pressure on the density of liquid ammonia in the process of measuring the liquid level of ammonia tank with flange type differential pressure liquid level gauge, this paper puts forward the solution of temperature compensation with linear interpolation method after analyzing the causes of the error. On this basis, the two-dimensional broken line table provided by DCs software is used to realize the piecewise linear processing of density temperature. After the density of liquid ammonia is accurately calculated, Furthermore, the liquid level of ammonia tank is calculated by using the relationship between liquid level and density. After commissioning,this measurement scheme has the advantages of high measurement accuracy, fast response speed, high reliability and good economy in the process of liquid ammonia measurement without increasing the cost.

关 键 词：温度补偿 线性插值法 分段线性化处理 DCS 二维折线表 

分 类 号：TQ113.5[化学工程—无机化工]