Theportables line from Panametrics, a Baker Hughes business, offers both ultrasonic liquid and gas clamp-on flow meters: The运输PT878GC气体;和运输PT900用于液体。这些超声波流量计利用超声波测量给定流体或气体的速度- also known as "flow" - and are used in a wide variety of fluid and gas applications, from wastewater and various fuels to natural gas and compressed air.
这些米连接到管道固定装置以测量流量在管道内。快速安装和仪表读数使我们的用户能够继续他们的进程without having to shut down。The meter’s portability allows the device tomove to numerous measurement locations，使其易于发现流程，验证流量计，或临时安装设备。
Of the两种可用类型的超声波流量计, we offer one for液体测量and one for气体测量:
- TheTransPort PT900uses a rugged and intuitive smart device/tablet and includes a new compact clamp-on fixture along with wireless capabilities. Itseasy-to-use designgives operators confidence that their liquid measurements are accurate.
- The运输PT878GC.is a clamp-on flow meter designed for short-term flow surveys in natural gas pipelines, compressed air, inert gas, or any other compressed gas application. With the ability tomeasure gas flow rates and then log and export important data，这种有用的仪表测量腐蚀性，腐蚀性，有毒，高纯度和无菌气体。
TheTransPort PT900portable ultrasonic liquid flow meter isPanametrics'最新的便携式夹具流量计。它很容易连接到管道夹具，以测量管道内的流量。用户无需切入管道并导致延迟和停机时间。PT900也可用于点击其他仪表或部署临时installations.Apps for the TransPort PT900 can now be found for Android and iOS mobile devices. -获取iOS的应用程序
这种流量计可以段d in just minutes for a variety of industries without needing to shut down:
- Water and wastewater / Cooling and heating water
- Ultrapure water and liquids / Water/glycol solutions
- Crude oil / Refined hydrocarbons
- 柴油和燃油/润滑油
- Chemicals
- Food and beverage
- Pharmaceutical
历史上，夹住流量计were limited to liquids因为现有方法无法在含有气体的金属管上工作。
Panametrics.developed a new technologythat extends all the benefits of clamp-on flow metering to gas measurement. This remarkable ultrasonic technology works with gases at high or low pressure in pipes made of metal and most other materials.
The运输PT878.便携式气体流量计是一种完整的超声波流量计量系统，用于测量大多数气体，包括：
- Natural gas
- 压缩空气
- Fuel gases
- 腐蚀性和腐蚀性气体
- 有毒气体
- High-purity gases
- 空气分离气体
可以在几分钟内安装此流量计，而无需关闭，从而避免昂贵的停机时间。
超声波流量计使用transit time to determine the liquid or gas flow in a pipeline.
Measured transit time consists not only ofthe time the ultrasonic signal spends in a fluid, but also of a portion of “dead time,”being the time that the electrical signal is converted into an acoustical signal and the time the acoustic signal travels inside the transducer.
如果是Custody Transfer, ultrasonic flow meters are used to calculate the flow, and thus volume, of product being transferred from one party to another.
Obviously then,accuracy is of great importance to all parties involved从那些正在采购和提供原料产品的人中，生产成精制材料，那些与将材料交付的那些任务，以最终收件人提供。
While there are many types of flow meters in use today,超声波流量计是迄今为止最流行的流量计, thanks in part to itshigh accuracy and low maintenance design。
When selecting an ultrasonic flow meter for your specific application,你需要问问自己：
- What are the unique properties of the fluid I am detecting?
- 存在什么压力或温度？
- 这是为了监管转移，市的计量，还是其他的东西？
- What is the min/max acceptable range for measurement?
- How large are the pipes (line size) you'll be attaching your detector to?
- 您需要便携式解决方案或静态吗？
Ultrasonic flow meters calculate and report volumetric flow rates, and通常使用过境时间to do so. Transit time is calculated whenthe difference between sound waves transmitted in the direction of fluid flow travels at a different speed than those traveling in the opposite direction。该计算差异与流体速度成比例。
Unlike other mechanical flow meters,超声波流量计没有任何活动部件。超声仪表通过存在提供额外的优势更易于安装，维护最小，特别是与其他流量计类型相比。
有两种类型的超声波流量计，由其测量方法定义，多普勒和运输时间。
Doppler
One of thedrawbacks to the Doppler version在于，它们需要测量的液体在其上具有气泡，以便为多普勒信号反射它们，以实现精确的测量。当然，问题是，您需要将气泡引入目标液体，2）不同速度的不同气泡行进，并且3）由颗粒反射的信号可能非常好地击中另一个颗粒或气泡，从而改变你的结果。
Transit Time
Transit time works in somewhat the opposite way of the Doppler method and does not require the presence of bubbles in your liquid. In the transit time version, measured transit time consists not only of超声信号在流体中花费的时间，但也是一部分“死区时间”，being the time that the electrical signal is converted into an acoustical signal and the time the acoustic signal travels inside the transducer.
By发送脉冲并测量其反射, the dead time is measured in real-time rather than using a preset value.
