The gas and oil industries are lucrative ventures that require proper control and measurement instruments to ensure a company meets its objectives or bottom line. One particular flow measurement tool that works accordingly to deliver accurate and reliable readings is a flow meter. However, like any other measurement tool, flow meters tend to lose their repeatability. When this happens, you don’t need to replace these expensive measurement tools. They just need to be recalibrated to restore their effectiveness. In this article, we will explain to you what flow calibration is, why it should be done, and how often it should be done. Continue reading for more insights.
What is Calibration in Flow Meters?
When a flow meter is used after some time, it tends to lose its accuracy levels if it has moving parts. Once this happens, a calibration process needs to be done to restore it to its normal accuracy levels. The process involves comparing readings of a master flow meter that accurately measure the flow meter that needs calibration. Flowmeter calibration is usually done based on what output you require from it. You can reset your flow meter to measure the amount of fluid passing through a pipe within a given time. You can also reset your flow meter to give you readings of the average temperatures of a liquid at intervals. Calibrating a flow meter makes measuring the flow rate in a vessel or pipe easier and accurate.
Why is Flow Calibration Necessary?
Flowmeter calibration plays an integral part in the flow measurement process. Flow meters are used in both domestic and industrial use. Flow meters have to work optimally to give desired readings. When they fail to give proper and accurate flow rate readings, it leads to a wastage of resources and funds.
Calibration of flow meters is done based on the application’s measurement requirements depending on the measured fluid product. Some flow industries may require a built-in calibration system because accuracy levels should be maintained at all times. The majority of flow meter manufacturers offer calibration services as an after-sale service or as part of quality control.
Devices Used in Flow Calibration
A flow meter calibration device is usually used when performing the calibration of flow meters. These devices are usually used to restore repeatability in a flow meter.
The flow meter calibration device is designed like a bench, and it features the following:
- Source holder
- A shield of the tested meter
- Control unit
- Tested detector connection units such as LV sources and counters
- Ionizing radiation source manipulator
- Calibration managing software to manage and store data
The technician who is about to conduct the flow calibration process needs to make sure that the system is programmed with the selected calibration option. This is done once all the components of the device have been assembled. The software needs to instigate the calibration process. The software selects relevant sources. This makes it easier for the software to act according to the instructions given. The gathered data is then kept in the database. If needed, a certificate can be printed.
Making Sense of Flow Calibration Outcome
Although there are several exceptions, the majority of flow meters export linear data. To know whether the flow meter that is being calibrated is working within the set parameters, non-linear data needs to be linearized. When you are done with the calibration process and gather the required data, you can establish whether performance is there. This information can be given as ‘difference between the calibration results and the standard values.’ Unless there is another measurement method, percentages are more useful when you want to establish the error rate in your device. Experts in the calibration industry can easily make sense of the range of permissible errors. This enables them to understand whether the instrument is working as expected or not.
How Often Should a Flow Meter be Calibrated?
No rule of thumb determines how frequently a flow meter needs calibration. It will all depend on several factors. Two major ones are the type of flow meter and the workload of the flow meter. Flow meters with moving components should be calibrated regularly, but those lacking moving parts can stay for years without calibration. The workload of the flow meter will also determine how often it needs calibration. If a flow meter works for many hours a day, it needs frequent calibration since it easily wears and tears.
With so many kinds of flow meters in the flow measurement industry, you need to understand the kind of calibration your flow meter requires to work effectively. Failure to calibrate your flow meter frequently may lead to poor performance in terms of accuracy and repeatability. Inquire from your flow meter supplier or manufacturer to determine the type of calibration and how often your flow meter needs flow calibration.