Ultrasonic flowmeter is a very convenient flow meter, especially in the large diameter water supply line, portable ultrasonic flowmeter can install the probe on the outer surface of the pipeline, to achieve no flow interruption, no damage to the original pipeline flow measurement, so it is welcomed by the majority of users.

Ultrasonic flowmeter has the advantages that other flowmeters can not compare, it will certainly become a flow meter for people to measure flow in the near future. Here are a few advantages of ultrasonic flowmeters for your reference:

First, the external clamp-type ultrasonic flowmeter can achieve non-contact flow measurement, even if it is a plug-in or internal paste ultrasonic flowmeter, the pressure loss is almost zero, and the convenience and economy of flow measurement is good.

Water, gas, oil and various media can be measured, and its application fields are very broad.

Third, the manufacturing cost of ultrasonic flowmeter is almost unrelated to the caliber, and it has a comprehensive competitive advantage of reasonable price, convenient installation and use in the large-scale runoff measurement occasions.

Portable ultrasonic flowmeter can realize a flowmeter in a variety of pipe diameters, various materials of the pipeline flow measurement, is used as a standard table for online calibration, comparison or verification during the selection of flowmeter type.

Fifth, the ultrasonic flowmeter has its flow measurement principle based on the length and time of the two basic physical quantities of traceability convenience, it can be predicted that it will surpass the flow meter of other principles to become the flow standard or even the carrier of the flow benchmark.

Sixth, the ultrasonic flowmeter operation energy consumption is small, can easily achieve long-term battery power supply, coupled with advanced intelligent host can easily carry out network wireless communication, its application prospects are broader. The development prospect of ultrasonic flowmeter is so promising, one is the inherent superiority of its flow measurement principle, and then it benefits from the rapid progress of microelectronics technology. At present, ultrasonic flowmeter is mainly used in the water supply industry or liquid portable ultrasonic flowmeter, in actual use, many users due to the use of ultrasonic flowmeter points are not good, the measurement effect is not ideal, so the ultrasonic flowmeter has a variety of doubts: "This flowmeter measurement is accurate?" Such questions have become a hot topic in the industry. The platform to evaluate the quality of a flowmeter is the flow standard device, through the statistics of the ultrasonic flowmeter verification conclusions over the past few years, we found that the indicators of the ultrasonic flowmeter are comparable to other velocity flowmeters, and when the flow rate is large enough, its linearity is particularly good.

So why do you feel that the ultrasonic flowmeter is not accurate in actual use? Through research and analysis, we find that users often ignore the following problems in use.

First, there is no correct verification or calibration of the ultrasonic flowmeter Any flowmeter needs to be verified or calibrated before use, and portable ultrasonic flowmeters are particularly important in this point. As we all know, portable ultrasonic flowmeters are generally configured with two to three sets of probes, which are suitable for different pipe diameter ranges, and each set of probes is matched with the host in a sense is a set of independent flowmeters. If the portable ultrasonic flowmeter is only verified or calibrated with a small probe on the flow standard device with a small pipe diameter, then in use if you use a large probe to measure the flow of a large pipe, it is equal to that you are using an unverified or calibrated flowmeter to measure the flow, and its measurement accuracy cannot be guaranteed, because the current level of technology cannot guarantee the interchangeability of the probe. Moreover, the difference between the size of the probe is a variable that cannot be ignored. Therefore, the correct method should be: based on the user's own use as a reference, as far as possible, the portable ultrasonic flowmeter is verified or calibrated on multiple pipelines on the flow standard device with the same caliber or close to the pipe used. At a minimum, ensure that each set of probes in the flowmeter configuration is checked. The portable ultrasonic flowmeter is equipped with multiple probes and may have several meter correction factors for different calibers. When using the flow meter to measure the flow, it is necessary to ensure the correct use of the instrument correction factor, not to forget to use and pay attention not to mix, should develop a good habit of confirming whether the instrument correction factor set in the host before the formal measurement is correct.

Second, ignoring the requirements of the flowmeter conditions and the use of the environment Any speed flowmeter has certain requirements for the flow field of the fluid in the pipeline under test, and the ultrasonic flowmeter is no exception. When the installation position of the flowmeter can not ensure the length requirements of the front and back straight pipe section, the measurement error caused by the instability of the flow field can not be ignored. Due to the limitation of measuring Wells, many users can not meet the installation requirements of the position measurement, resulting in increased measurement errors. The time difference ultrasonic flowmeter is particularly sensitive to bubbles mixed in the water, and the subsequent flow of bubbles will cause the instability of the flowmeter value, and the accumulated gas will cause the flowmeter to fail to work if it coincides with the installation position of the probe. Therefore, the installation of ultrasonic flowmeter should try to avoid the pump outlet, pipeline high point and other susceptible to gas position, the installation point of the probe should also try to avoid the upper and bottom of the pipeline, installed in the range of 45° Angle with the horizontal diameter, but also pay attention to avoid weld and other pipeline defects. The installation and use of ultrasonic flowmeter environment should pay attention to avoid strong electromagnetic interference and vibration, in use, we found that under the high-voltage line, the roadside of dense vehicles, the use of mobile phones or walkie-talkies near the host will have a more or less impact on the measurement.

The portable ultrasonic flowmeter probe is installed outside the pipeline, which directly measures the flow rate of the fluid in the pipeline, the flow rate is the product of the flow rate and the flow area of the pipeline, and the pipeline area and the length of the channel are calculated by the user manually input the pipeline parameters. The accuracy of these parameters directly affects the measurement results. That is to say: even if the flow rate is measured accurately, if you enter an inaccurate set of pipe parameters, the measurement results are not accurate. The acquisition of pipeline parameters must be the actual measurement method, with access to design drawing data and inquiry familiar with the situation of the personnel may have errors, because the actual construction situation is often different from the design parameters, the manufacturing deviation of the pipeline is sometimes not negligible, the use of a period of time of the pipe wall thickness and other parameters will also change over time. The actual measurement of pipeline parameters should also pay attention to the rationality of the method, and the measuring tools and instruments used for measurement should be calibrated. When measuring the outer diameter of the pipeline, it is necessary to pay attention to the influence of the outer protective layer of the pipeline and the corrosion and dirt of the outer surface on the measurement. When the portable ultrasonic flowmeter is used for flow measurement on the small pipe diameter, the error caused by the inaccurate input of the pipe inner diameter can not be ignored, and some people recommend that the portable ultrasonic flowmeter should be used in the pipeline above DN300. The installation distance of the probe is an important measurement parameter that must be accurately guaranteed. In order to ensure that the best signal strength is found, some users move a probe to find the signal, often the signal has the installation distance of the probe is wrong, and the other is lost. The correct method is: to move the two probes in parallel, find the appropriate installation point on the premise of ensuring that the installation distance of the probe meets the requirements, and be sure to use the measured method to confirm the installation distance of the probe is accurate after the signal is found. The influence of pipeline lining on the measurement is also very great, some old pipe lines using cement mortar lining anti-corrosion, if it is ignored in the measurement, it will produce a great error, because the thickness of cement mortar lining is generally not a negligible number, plus its rough surface is easy to adhere to mud sand, easy to fall off in pieces, which may have a great impact on the measurement. When measuring, if there is no input lining parameter, the signal can not be found according to normal operation, it should be considered that the pipe may be lined.

Ultrasonic flowmeter is a good flow meter, it brings us the convenience and economy of flow measurement is unmatched by other flowmeters, we do not misunderstand it because of their carelessness, practice has proved that the vast majority of problems in the use of ultrasonic flowmeter flow measurement are caused by human factors, The ultrasonic flowmeter has taken on a lot of responsibilities for us, and it is our trusted good friend.