Flow meters have become a necessary tool throughout a range of industries and are integral to many companies in the industrial, chemical, energy, scientific laboratory and aerospace sectors. Understanding chemical make up and flow rates are essential to maintaining efficient and safe operations across industries. Magnetic particle testing can be an important component in particular flow meter designs, and a field indicator is a major factor in the functioning of any magnetically based system. Understanding the role and types of field indicators is critical to understanding the overall effectiveness of your magnetic flow meter.
What Is a Magnetic Flow Meter?
The magnetic flow meter is the third most commonly used type of measuring tool throughout a range of operations. The principle of electromagnetic induction serves as the base of this system’s functioning, and results represent a proportional difference between the flux lines and perpendicular flow velocity. The process is completed through an applied magnetic field placed on a metering tube. This data is based on a continually changing magnetic field because, if the field were consistent, differences in flow would be nearly impossible to distinguish.
The Role of the Field Indicator
Because an ever-changing magnetic flow is essential to the functioning of a magnetic flow meter, the magnetic field must be continually monitored to ensure the consistency of data. As such, a functioning field indicator is an important piece to the overall accuracy and efficiency of the meter. Field indicators have been designed to ensure that a magnetic field flows in the desired direction and at the adequate strength. Accurate measurements are crucial to a multi-directional machine like a magnetic flow meter. Obtaining the field strength requires direct interception of the field line, which often necessitates the addition of a small hole in the line.
Types of Field Indicators
Hall effect gage options detect the strength of a tangential magnetic field by measuring the strength of an adjacent area, as the magnetic field is applied. While these are ideal for assessing quantitative measurements repeatedly, they are not optimal for multi-directional flow devices because they commonly have to be re-calibrated. The hall effect gage is a simple and easy to use small flat device that offers long-term durability. However, due to their residual readings, they are not the most reliable devices, and they can only be used on flat areas. These are also not the best option for a multi-directional field.
Quantitative Quality Indicators are the most commonly used devices when measuring multi-directional flows. As such, they are the ideal choice for a magnetic flow meter. As a flux sharing device, they come with a number of advantages and disadvantages. While they provide excellent reliable data when used with a continuous magnetic flow, they require extensive maintenance and cleaning. They can easily become dirty and corrode, so these devices require careful attention and more frequent replacement.
Magnetic particles are often used with field indicators to detect the flow and composition of a particular gas or liquid. Highly reactive and minimally retentive particles are added to the substance being measured. They are designed to alert indicators to inconsistencies in the flux line. The particles can be used as a wet mix or dry solution.
While only a small piece of your overall flow meter, the field indicator is an essential component to the effective operation of your magnetic flow meter. Understanding their purpose in your larger system is an important step in understanding your entire device and ensuring its continued functioning.