| Vol 1 No. 9 Date: August 24, 1999 Subject: Flow Measurement News From: McCrometer, "The Flow Measurement Specialists" ........ http://www.mccrometer.com ........ ******************************************* This newsletter is e-mailed by McCrometer monthly to subscribers worldwide. It consists of flow measurement information of interest for professionals in this field. For More information on our complete line of flowmeters go to: http://www.mccrometer.com Ask the Experts... PROPELLER METER APPLICATIONS In the world of flowmeters there are hundreds of choices for the end user. While newer technologies often grab the spotlight, many tried and true technologies often get overlooked in the zest for the newest. Occasionally, this newsletter would like to look back and recognize the distinct advantages older technologies can bring. The propeller meter is the first to be reviewed in this way. The propeller meter is a distinct type of flowmeter technology that has been in service for over 50 years. Propeller meters may get confused with turbine meters in other countries but in the United States, the propeller meter is certainly not the same as the turbine meter. A turbine meter comes in many different forms, such as the municipal water turbine meter, the industrial water turbine meter, and the industrial gas turbine meter. The main difference between propeller and turbine meters is in the rotating element and the means to support it. A propeller is usually made of thick injection molded plastic while turbines are made of plastic or metal and much thinner. A propeller faces directly into the flow and is held by a single, rugged bearing assembly downstream. Turbines are usually held on both sides by two, lighter-weight bearing assemblies. Propeller meters are intended to measure water flowrates mechanically. The reading from a propeller meter is an indicator of the instantaneous flowrate and the totalized volume. The reading is purely mechanical and requires no power. This is perhaps the propeller meter's single greatest advantage: to measure flowrate accurately without the need for power. The meters can be used in remote areas where power is non-existent or in temporary locations where power is hard to access. Examples of remote areas include farm irrigation fields and gold mining operations. Temporary locations include batching applications and municipal fire hydrant measurement. With no electrical components, the meters are capable of withstanding harsh conditions such as lightning and extreme temperatures. Power failures and dead batteries are of no concern to a mechanical meter. (And they are completely Y2K compliant!) Intended for water service, the meters are relatively low cost and economical even when the service need is short. This is especially true when the propeller meter, for a short time, needs to tolerate certain chemical components in the flow. After the service is completed, the meters are discarded. The user can avoid using expensive materials of construction that a permanent meter would require. Propeller meters can also be fitted with a variety of electronic readouts and outputs. They can also be made of high-grade stainless steels for harsh or clean environments. The propeller meter is an accurate, versatile, yet economical solution to many flow measurement needs. The next time you go tuning for a flow meter, don't forget the "oldies but goodies" station. . . It may save you a lot of money! Get more information on modern propeller flowmeters and how they can save you money and headaches. For a complete overview of McCrometer's Mc® Propeller flowmeters, click on this link: http://www.mccrometer.com/mc If you have suggestions for newsletter topics you would like to see, please contact us at info@mccrometer.com |