Showing posts with label Fischer & Porter. Show all posts
Showing posts with label Fischer & Porter. Show all posts

Basics of Variable Area Flowmeters

Variable Area Flowmeter (Rotameter)
Rotameter (ABB)
Flowmeters are a class of devices or instruments used to measure rate of fluid flow. Flow measurement stands as a vital input to many process operations across almost every industry. Applications can range from precise measurement of very small gas flows to oil or water flows through large diameter piping systems. There are a number of technologies employed for measuring fluid flow, each with attributes of design, performance, or cost that can make them an advantageous choice for a particular application.

Variable-area flowmeters are designed to measure flow using a precisely fabricated obstruction in the flow path that is repositioned in a tapered flow tube by changes in fluid flow.

Variable Area Flowmeter (Rotameter)
Rotameter (ABB
A rotameter is a flow indicator consisting of a tapered tube containing a plummet. The plummet is generally a solid object and sometimes referred to as a float. Rotameters rely on gravity as part of their operating principle, so the instrument must be installed such that the inlet is at the bottom and fluid flows directly upward through the tapered tube. As fluid flows through the tube, a pressure differential develops across the plummet. This creates an upward force on the plummet, moving the plummet in the direction of the flow. The flow area around the plummet increases as it moves from the narrow portion of the flow tube to a wider portion up the measurement scale. As the available flow space around the plummet increases, the upward force on it decreases. Eventually, the equalization between the pressure force and the weight of the plummet occurs and the float stops moving. The flow rate is indicated by the plummet's position relative to a pre-calibrated scale printed along the length of the tube. The same type of system can be used to measure liquid or gas flow, with the rotameter being specifically calibrated for the fluid to be measured. It is common to employ a rotameter with an integral needle valve as a metering device for delivering a precise fixed flow of a fluid into a process.

These devices are generally inexpensive and easy to apply. Key application considerations include a vertical installation orientation, matching the rotameter to the fluid, and providing physical access to read the indicated flow.

Industries use rotameters primarily as indicating devices. Rotameters enjoy a wide range of applications throughout research and manufacturing processes. Share your flow measurement challenges with instrumentation specialists, combining your own process knowledge and experience with their product application expertise to develop effective solutions.

ABB Rotameters

ABB rotameter
ABB rotameter
Rotameters, also known as variable area flowmeters, are designed to measure the flow of liquids or gases via a tapered tube and float system. They are accurate, reliable and simple to install and maintain. The biggest benefit is their low cost, which has made them a popular choice for many flow applications since Fischer & Porter introduced the first mass-produced glass tube flowmeter in 1937. TECO was the first firm to represent and sell the Fischer & Porter Rotameter Line, dating back to March, 1947.

The following brochure is designed to help you select the right ABB rotameter for your application. You can read it below, or download your own copy of the ABB Rotameter brochure from this link. If you have questions or are ready for a quote, simply contact TECO at 800-528-8997 or visit teco-inc.com/ABB.