EASTERN INSTRUMENTS



Centriflow<sup>�</sup> Solids Mass Flow Meter Technical Information
The CentriFlow Meter from Eastern Instruments is a Solid Particle Mass Flow Meter that is durable, accurate, maintenance-free, compact, and cost-effective. It is unique and positioned to replace weigh belts, impact meters, loss in weight meters, and static weigh scales, anywhere that accuracy, low maintenance, and zero drift are paramount.

Please see below for additional information regarding the various options that are offered for our CentriFlow family of meters. If you do not see an option that suits your particular application, don't worry. We have an engineering team that is ready to assist you with a custom solution for your application, so contact us and we will be happy to assist.

DRYWALL AND WALLBOARD MANUFACTURING:
Raw Calcium Carbonate Measurement


PROCESS PREDICAMENTS



The customer needed to accurately measure the mass flow rate of crushed calcium carbonate (limestone) to control the feed into a mill. The calcium carbonate was to be moved by a screw conveyor, through a mass flow measurement system, and then into the mill. The meter needed to be enclosed in order to contain the calcium carbonate through the process. The density of the calcium carbonate is 90-105 lb/ft3 with a maximum flow rate of 15 ton/hr and a minimum flow rate of 10 ton/hr. This meant that the flow meter needed to be capable of handling and accurately measuring a volumetric capacity from 191 to 333 ft3/hr (5.54 to 9.43 m3/hr). The flow meter needed to provide output to a PLC to control the feed screw conveyor speed to a mass flow set point and have a local display indicating flow rate and flow total.






EASTERN INSTRUMENTS SOLUTION


Raw Calcium Carbonate Flow Measurement

The customer installed a CentriFlow Meter. The unit selected for installation, was a CentriFlow 6" Type II Meter, being fed vertically from a screw conveyor. The Type II Configuration is ideal for processes that are highly pulsating due to the feed system and/or products that need to be contained or enclosed. An integrated Ratemeter/Totalizer was used to locally display flow rate and to totalize the flow through the meter. The Ratemeter/ Totalizer also averaged the 4-20 mA output signal (proportional to the flow rate) from the meter to the customer's PLC. This allowed the customer's PLC to control the screw conveyor's speed, which in turn controlled the flow rate of product to the mill.


CONCLUSIONS



Once the CentriFlow Meter was installed and the calibration was completed and the calcium carbonate flow was controlled. Themeter performed well within the desired accuracy of +/-0.25% of the full-scale volumetric flow rate. This allowed excellent control of the flow to the mill and the customer was well satisfied.



MATERIAL TEST REPORTS:
Drywall and Wallboard




The CentriFlow has measured a variety of ingredients for manufacturing drywall including gypsum, calcium carbonate and powdered lime. For plywood, the CentriFlow is often used in order to properly ratio the wood chips and shreds with the adhesive used to manufacture the plywood.



CHOOSING THE RIGHT EQUIPMENT



Type I Meter
Type I Meter:
Open Style Flow Meter
Type II Meter
Type II Meter:
Enclosed Style Flow Meter