压力对西门子超声波液位计测量精度的影响  

Influence of Pressure on Measurement Accuracy of SIEMENS Ultrasonic Level Gauge

作　　者：刘超 LIU Chao(Fluor (China) Engineering & Constraction Co.,Ltd.,Shanghai 200241,China)

机构地区：[1]福陆(中国)工程建设有限公司,上海200241

出　　处：《自动化仪表》2019年第4期82-84,共3页Process Automation Instrumentation

摘　　要：超声波液位计因其测量精度高、成本低的特点,在项目应用上常被用于常温常压容器内的连续液位值检测,特别是在敞口容器和水渠上应用广泛。由于其探头的设计对测量压力有一定限制,因此对于密闭的、带微正压容器的液位检测设计通常选用其他形式的液位计,这大大限制了超声波液位计的使用范围。为了验证超声波液位计能在微正压的工艺条件下正常使用,对西门子LUT400系列超声波液位计在0～7.5 kPa环境下进行了试验。分别测试了当压力从升高到降低时超声波液位计的上行/下行测量误差,并将其和重复性数据进行比对分析。分析结果表明,超声波液位计至少在7.5 kPa工作环境下,其性能和测量精度满足产品本身的设计性能,为今后超声波液位计在密闭、微正压工艺条件下的使用提供了有力的选型依据,拓展了其使用的范围。Ultrasonic level gauge is often used for continuous liquid level detection in normal temperature and pressure vessels because of its high measurement accuracy and low cost,especially in open containers and ditches.Due to the limitation of the design of its probe upon pressure measurement,other types of level gauges are usually used in the design of liquid level detection for closed,micro-positive pressure vessels,which greatly limits the scope of use of ultrasonic level gauges.In order to verify that the ultrasonic level gauge can also be used normally under the process conditions of micro-positive pressure,the SIEMENS LUT400 series ultrasonic level gauge is tested under the environment of 0~7.5 kPa.The upwards measurement error,downwards measurement error and repeatability data of the ultrasonic level gauge are compared and analyzed respectively when the pressure increasing to decreasing.It is concluded that the performance and measurement accuracy of ultrasonic level gauge can meet the design performance of the product under the working environment of at least 7.5 kPa.It provides a powerful basis for the future use of the ultrasonic level gauge under the conditions of airtight and micro-positive pressure,and expands the scope of its use.

关 键 词：超声波液位计 压力 ST-H换能器 测量误差 测量精度 

分 类 号：TH86[机械工程—仪器科学与技术]