Sensors are subjected to a natural aging process making regular checks with trusted measurements essential. By applying networking and information technologies in manufacturing the related workload and possible errors are reduced to a minimum.
Why is calibration important?
Anybody dealing with instruments which are installed directly in the production process has already experienced the following situation: the process instrument is installed in the pipe, bypass or tank, the initial commissioning and validation is finished, and the sensor is connected to the local PLC. However, after time, thermal and chemical loading as well as physical stress from sample flow and line vibrations could cause the sensor to age and drift away from its original set point. This means that we cannot be sure that the measurement data really represents the sample condition and that our products are within the desired quality limits. In short, the quality of a company’s production becomes unreliable.
To guarantee the correctness of the measured value over the course of time it is necessary to periodically perform calibrations. According to The Automation, Systems, and Instrumentation Dictionary by ISA (International Society of Automation), the word calibration is defined as “a test during which known values of measurand are applied to the transducer and corresponding output readings are recorded under specified conditions.”
In contrast to adjustment, where we actively alter the measuring instrument to match the reference, the calibration is a simple comparison of two values: one being the measured value from the process instrument under test, the other being a trusted reference value. This could be represented by a reference sample traceable to a standardization laboratory, or trusted measurements from the laboratory.
Common procedure in the beverage industry
In the beverage industry, for example in beer or soft drink production, the latter is typically the case. To perform regular checks of the process instrument a sample is taken from the line and the process values are recorded. The sample is then brought to the laboratory and analyzed using trusted laboratory instrumentation. When the analysis is finished the values are compared. If the difference exceeds some predefined limits for consecutive measurements, the process instrument is adjusted accordingly. Making adjustments after only a single calibration should be avoided, as process stability or laboratory measurement variation could falsify the measurement. Typically, the procedure is time-consuming, involves a lot of manual data handling, and can be prone to errors.
Outlook with focus on Industry 4.0
Looking at the industrial environment of the future, especially with focus on Industry 4.0, we should dare to envision automatic data exchange between devices. It is likely that we will see instruments interchanging data seamlessly, while the operator-related workload is reduced to a minimum, thus allowing quantifying time that was previously wasted for new method improvements and future product development. In practical terms, measured data from process and the appropriate data from the laboratory would find themselves in the same data cloud, ready to be analyzed, displayed, visualized, or transmitted to any other system using standard application interfaces.
Is this some future gimmick discussed at the roundtables of future industry forums or hard-fact reality?
Complete your beverage analysis
To complete your beer,or soft drink analysis, Anton Paar introduces a custom-tailored setup for the laboratory and process line. The direct connection of process and laboratory analyzing systems with the Davis 5 evaluation software, semi-automates and simplifies the calibration and adjustment of process sensors with laboratory reference results. Data integration streamlines the documentation process, drives data consistency, and minimizes transcription errors. Your organization can create value from information by moving from physical to digital.
From any office in the plant, you can access integrated data from all systems at any time. While instruments talk to each other to share information, advanced analytics and the visualization of real-time data from multiple measuring points along the production process are allowed.
Benefit from the all-around traceability and powerful reporting, from the first intake of raw material to the shipment of the final product.
To learn more follow the link below.