Oval Gear flow meter รุ่น OG900 [Basic Counter]

Overview

The Oval gear flow meter is a kind of Positive Displacement Flow meter. As the fluid being measured passes thru the meter, it rotates 2 oval gears in measuring cavity to displace a precise volume of fluid. A sensor detects the gear rotation to determine displaced volume and flow rate.
Fluid pressure rotates the oval gear, Figure 1. In position (a), the fluid exerts a clockwise driving force on gear A. There is no driving force on gear B. It is perpendicular to the flow so the fluid forces on gear B. At position (c), all the driving force is on the gear B. This alternative driving force provides a smooth rotation of almost constant torque. The meter design minimizes the slippage between the gears and the measuring cavity wall. As a result, the oval meter is
less affected than other designs by the liquid’s viscosity and lubricity.

Application

Oval gear flowmeter is mainly used for high value liquids such as oil, chemical etc. Main applications include unloading, transfer and consumption monitoring.

Oval Gear Flowmeter Features

• Only Two Moving Parts
• Higher Accuracy, 0.5% or 0.2%
• Standard Viscosity up to 2,000 cP (Centipoises = mPa.s)
• Size of wide flow ranges 0.04-340 m3/h (18-37,396 GPM)
• Wide range of working environment -20 ~ +180 °C

Technical Specification

• Allowed basic error : ±0.5%, ±0.2%
• Allowed operating pressure (Mpa) : Cast iron (A), Stainless steel (B) 1.6 Mpa
• Casted steel (E) ,DN15 to DN100 6.4 Mpa
• Pipe connecting flange : JB78-59, 79-59
• Viscosity (mPa.s) : class 0.5 : 0.6-200
• class 0.2 : 3-200
• Measured media temp. : -20~+60 °C

Flow range

 

Notes:
1. The flowmeter should be selected inaccordance with
the flow range,but not in accordance with the pipe diameter.
2. If the temperature of the metered liquid is
between 100-200 °C,the max flow rate mus subtract by 10%.
3. While metered liquid is not petroleum product, if it viscosity is
equivalent to the listed in the table, the flow range is also
equivalent to that listed above.
4. For chemical high temperature, and high viscosity liquid, consult us.
5. While the metered media have strong corrosive,
the max flow mus reduc by 1/3.

Table 1 : Diameter and flow range of Oval meters for class 0.5

 

Table 2 : Diameter and flow range of Oval meters for class 0.2

Performance

The performance of the meter’s high accuracy and low pressure loss is shown in the following error versus pressure loss characteristics.

1. Space petrol           0.7      mPa.s

2. Water                        1      mPa.s

3. Light diesel              5      mPa.s

4. Transformer oil      20     mPa.s

Error and pressure loss characteristics for class 0.5

 

 

 

 

 

The above accuracy curve shows the meter error when the metered liquids have different
viscosities, and the meter error can be adjusted up and down the Axis 0 by the accuracy
adjustor to optimize the error.

 

 

For any liquid when the flow range ratio is reduced.
The meter accuracy can be improved, and the error
will be adjusted between ±0.2% by mans of accuracy adjustor.

 

 

 

 

 

Dimension Oval meter of DN10~40

Unit : mm.

 

 

 

Oval meter of DN50~100

 

A dimension for cast iron Oval meter         

Oval meter of DN150~200

Unit : mm.

 

 

 

 

 

 

 

E dimension for cast iron Oval meter