Oval Gear Flowmeter

Principle and Structures: 

Oval Gear Flow meter is equipped with a pointer and printing wheel accumulation device, and can directly display the liquid accumulation flow through the pipeline on the spot. The accumulative, quantitative and instantaneous flow remote transmission control can be realized by attaching the transmitter and the electric display instrument to the counting mechanism. High temperature and high viscosity liquid can be measured by adding radiator or ellipsoid undertooth.

Oval gear flowmeter consists of flow transmitter and counting mechanism. A high temperature flowmeter if formed if a radiator is installed between the transmitter and the counting mechanism. The transmitter consists of a metering chamber and a sealing coupling with a pair of elliptical gear rotors. The counting mechanism comprises a deceleration mechanism, a regulating mechanism, a counter and a transmitter Counting mechanism Number of interfaces of transmitter Regulating mechanism Sealing coupling Top cover Flange Cover plate Shell Bottom cover Oval gear Structure diagram The metering chamber has a crescent cavity composed by a pair of oval gear and cover plate as the metering unit of flow. The oval gear is rotated by the pressure difference between the inlet and outlet of the flowmeter so that the liquid is continuously measured by the crescent cavity and sent to the outlet. The liquid that flows every turn is four times of the crescent cavity. By sealing coupling, the total number of turns of oval gear and the speed of rotation are sent to the counting mechanism or transmitter. Thus, we can know the total amount of liquid and instantaneous flow through the pipeline .

Technicial Parameters :

DN mm	Flow Range 2 to 200mPa.s	Flow Range 2 to 200mPa.s
10	0.08—0.4 m /h	0.08—0.4 m /h
15	0.3—1.5 m /h	0.3—1.5 m /h
20	0.6—3 m /h	0.6—3 m /h
25	0.8—6 m /h	0.8—6 m /h
40	3—15 m /h	3—15 m /h
50	4—24 m /h	4—24 m /h
65	8—40 m /h	8—40 m /h
80 (light type)	8—40 m /h	8—40 m /h
80 (heavy type)	10—60 m /h	10—60 m /h
100	15—100 m /h	15—100 m /h
150	34—190 m /h	34—190 m /h
200	56—340 m /h	56—340 m /h

Installation Guidance :

A matching filter shall be installed before the flowmeter, and the outlet of the matching filter is connected to the inlet of the flowmeter. The arrow points on both bodies are consistent with the flow direction of the liquid. When the liquid under test contains gas, the gas elimination filter should be installed before the Flowmeter. No matter whether the pipeline is installed vertically or horizontally, the oval gear in the flowmeter shall be installed in a horizontal position (i.e. the gauge disc shall be perpendicular to the ground). When the flowmeter is properly installed, if it is not easy to read, turn the counter to 180 degrees or 90 degrees. The new flowmeter pushes the elliptical gear several times from the exit with a bamboo stick before installation. If it doesn’t move, soak in diesel oil (Avoid sediment after factory check). Flow control valve should be installed at the inlet of the Flowmeter, and open and close valve is installed at the outlet. When using open and close valve, start slowly, do not suddenly open to prevent “water hammer” phenomenon. Before installing the flowmeter on the new pipeline, the pipeline needs to be flushed, and the straight pipe section (instead of the position of the Flowmeter) is used to prevent welding slag, sundries and so on from entering the flowmeter. It is strictly forbidden to check the flowmeter of cast iron and steel with water. The flow size of the flowmeter in use shall not exceed the technical requirements. The flowmeter operates at a maximum flow rate of 50-80%. If the tested liquid is chemically corrosive, a flowmeter of stainless steel should be selected.