A Cylinder gear flow meter is a micro digital positive displacement flow meter. Can measure very small flow rates and quantify small volumes of liquid. High and low-temperature resistance (-196℃-200℃).

Gear flow meter working principle

Gear flow transmitter is a type of positive displacement flow transmitter. It is a high-precision transmitter for measuring volume flow.

With the flow of the medium, the gears mesh and rotate. Under the action of the fluid flow, a pressure difference is formed at both ends of the instrument inlet and outlet. There is no need for a power supply. A pair of gears rotate freely. The cavity between the gears is filled with liquid. Discharge and measure the number of revolutions of the gear to know the flow of liquid and liquid flowing through the instrument.

The rotation speed of the round gear transmitter is detected by the sensor coil in the signal amplifier mounted on the watch case. The signal amplifier is not in contact with the measured medium. When the transmitter gear cuts the magnetic field lines generated by the permanent magnet in the housing, it will cause the magnetic flux in the sensing coil to change.

The sensing coil sends the detected magnetic flux periodic change signal to the preamplifier, amplifies and reshapes the signal, generates a pulse signal proportional to the flow rate, and sends it to the unit conversion and flow integration circuit to obtain and display the cumulative flow value. At the same time, the pulse signal is sent to the frequency current conversion circuit, which converts the pulse signal into an analog current quantity, and then indicates the instantaneous flow value.

The round gear transmitter has high machining accuracy and precise installation. The rotation of the gear is scanned non-contact, and each tooth generates a pulse with a very high resolution. Cylindrical gear transmitters can measure very small flow and quantify the small volume of liquid.

Extended reading: Tri clamp-Stainless steel Sanitary Positive Displacement Flow Meter

Oval Gear Flow Meter

Oval gear flow meters (also known as displacement flow meters, gear flow meters) are a type of positive displacement flow meters, which are the most accurate type of flow meters. It uses a mechanical measuring element to continuously divide the fluid into a single known volume part, and measures the total flow volume according to the number of times that the metering chamber is filled and discharged with the volume part of the fluid successively and repeatedly. The oval gear flowmeter can be made of different materials (cast iron, cast steel, 304 stainless steel, 316 stainless steel), and is suitable for flow measurement in the chemical, petroleum, pharmaceutical, electric power, metallurgy and food industries.

The measurement principle of the gear of the Cylinder Gear flow meter is similar to that of the oval gear flow meter. But the gear shape is different.

Oval Gear Flow Meter Advantages and Disadvantages

The oval gear flowmeter uses the principle of volumetric type. Suitable for testing various viscous liquids. Flow measurement of heavy oil, polyvinyl alcohol, resin and other high-viscosity media.

Advantages:

1. The measurement accuracy of the oval gear flowmeter is high. The basic error is generally ±0.5%R. Special ones can reach ±0.2% R or higher. It is especially suitable for use in the field where high-precision measurement is required.
2. It has no influence on the measurement accuracy when measuring the distortion of the flow velocity field of the rotating flow and the pipeline choke. There is no requirement for the front straight pipe section.
3. The oval gear flowmeter can be used to measure high-viscosity fluids. Wide flow range. It is generally 10:1 to 5:1. Special ones can reach 30:1 or greater.
4. With direct reading of on-site flow. It can measure the cumulative total without external power supply. The display is clear and the operation is convenient.

The oval gear flowmeter is a combination of measuring elements. The indirect method of volumetric flow measurement. Compared with other flow meters that use velocity to derive flow. Oval gear flow meters have the following disadvantages:

1. The design of the measurement structure is complicated. Large and bulky. In particular, the flowmeter with a larger caliber is bulky. Compared with other general flow meters (such as orifice flow meters, float flow meters, electromagnetic flow meters, vortex flow meters). The measured medium type, medium working condition (temperature, pressure), and caliber are relatively limited. The scope of adaptation is narrow.
2. Not suitable for high and low temperature occasions. Because of the thermal expansion and deformation of parts at high temperatures, the material becomes brittle at low temperatures. The usable temperature range is -30～+180℃. The maximum pressure is 10MPa.
3. The oval gear flowmeter is only suitable for clean single-phase fluids. When the fluid contains particles or dirt, a filter must be installed upstream. Not only increases the pressure loss, but also increases the maintenance work. If measuring liquids containing gas, a gas separator must be installed.
4. Poor safety performance during measurement. If the measuring element is stuck in motion, the fluid cannot pass through. The cut-off piping system cannot be used.
5. During the measurement process, the pulsation caused by the flow of fluid during the measurement process. Large-diameter flowmeters can also generate noise. Even the pipes vibrate.

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Featured positive displacement flow meters for sale

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Sino-Inst, Manufacturer for Gear flow meter for Microflow. For example crude oil flow meter, diesel flow meter, gasoline flow meter.

Sino-Inst’s Gear flow meter for Microflow, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, the US, and other countries.

Rroots Gas Meter is a meter that accurately measures gas flow. Based on the principle of volumetric measurement. It is an ideal natural gas and gas flow meter.

Features of Rroots Gas Meter

1. High degree and good repeatability. The internal rotor is precision machined and balanced and tested, and it rotates without contact. Good oil lubrication ensures that the accuracy of the flowmeter remains unchanged and the working life is long.
2. There is no need for straight pipes before and after the flowmeter, so it can be installed in a narrow environment.
3. The starting flow is small and the range ratio is wide, which is suitable for measuring the gas flow with large changes.
4. The measurement degree is not affected by pressure and flow changes, with stable performance and long life.
5. Good versatility, all Roots flow sensors can use universal accessories.
6. Configure RS-485 communication interface and IC card dedicated signal concentrator. It can also form a remote data acquisition machine monitoring system through GPRS/CDMA, internet and telephone network. It is convenient for centralized data collection and real-time management.
7. The circuit adopts surface mount technology. Compact structure, strong anti-interference ability and high reliability.
8. Adopt high-performance microprocessor and modern digital filtering technology. The software has powerful functions and superior performance.
9. It adopts floating point calculation and five-segment meter coefficient automatic correction, and has fault self-diagnosis and alarm functions.
10. Using micro-power high-tech, internal and external power supply to work. The power consumption of the whole machine is low, and it can work continuously for more than five years with only a 2#3.6VDC lithium battery.
11. The flow value is displayed on the spot, with multiple signal output functions.
12. A high-contrast liquid crystal display is used. It can display the standard cumulative flow, standard volume flow, working condition volume flow percentage, medium temperature, pressure value and battery consumption percentage.
13. With real-time data storage function.
14. The protection grade of the flowmeter housing is IP65.
15. The explosion-proof mark is ExibllCT4.

Extended reading: Gas Mass Flow Meter

Specifications of Rroots Gas Meter

Executive standard	Measurement of gas flow in closed pipelines—”Gas Lumbar Flowmeter” (JB/T7385-94)
Caliber and connection method	25, 40, 50, 65, 80, 100, 125, 150, 200, 250 are flanged
Accuracy class	±1.5%R (±1%R needs to be specially made)*
Instrument material	Body: cast aluminum or cast iron; rotor: high-quality aluminum alloy; converter: cast aluminum
Conditions of Use	Medium temperature: -10℃～+60℃ Ambient temperature: -30℃~+60℃; Relative humidity: 5%～90% Atmospheric pressure: 86～106KPa
Power supply	A. External power supply: +24VDC±15%, ripple ≤±5%, suitable for 4-20mA output, pulse output, RS485, etc. B. Internal power supply: 1 3.6VDC lithium battery, when the voltage is lower than 2.0, an undervoltage indication will appear.
Whole machine power consumption	A. External power supply: <1W; B. Internal power supply: average power consumption ≤1W, can be used continuously for more than three years.
Output signal	Pulse signal, 4 ~ 20mA current signal, IC card control signal
Communication output	RS485 communication
Real-time recording	Start-stop record, daily record, fixed time interval record
Signal line interface	Internal thread M20×1.5 or others
Explosion-proof grade	ExibIICT4
Protection level	IP65

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Rroots Gas Meter Working Principle

Rroots Gas Meter structure

The flow meter is composed of two parts: Roots flow sensor and display instrument.

1. End cover I
2. Magnetic coupler
3. Gland I
4. Shell
5. Waist wheel assembly
6. Gland II
7. Bearing
8. End cover Ⅱ
9. Synchronous gear
10. Oil sling
11. Oil cavity

The working principle of gas Roots flowmeter

Gas Roots flowmeter is a positive displacement flow meter.

When the gas passes through the flow meter, the pressure difference generated between the inlet and the outlet acts on a pair of waist wheels connected with high-precision synchronous gears to drive the waist wheels to rotate.

During this period, the enclosed space formed between the waist wheel and the inner wall of the housing and the gland is periodically inflated and exhausted by a metering chamber. The speed of the waist wheel is proportional to the volume of gas passing through the flow meter.

The rotation of the waist wheel is transmitted to the mechanical counter or output flow pulse signal through the magnetic coupler, so as to accumulate the volume flowing through the metering cavity to achieve the purpose of metering.

Extended reading: Buy Digital Gas Flow Meters & Controllers For Air-O2-N2-CO2

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Sino-Inst, Manufacuturer for Rroots Gas Meters. For example: crude oil flowmeter, diesel flowmeter, gasoline flowmeter.

Sino-Inst’s Rroots Gas Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, US, and other countries.

Roots meter is also called Lumbar flow meter, which is a positive displacement flowmeter. Roots flowmeter for Liquid is called liquid Roots flowmeter. Gas Roots flowmeter is used for measuring gas.

Features of Liquid Roots Meter

• It has the characteristics of light weight, high precision up to 0.1-0.5 grade, and easy installation and use. It is one of the typical products of positive displacement flowmeter
• This Liquid Roots Meter is manufactured by introducing advanced technology from BOPP&ReuthER from Germany and Oval from Japan.
• Liquid Roots Meter can measure the flow of gasoline, kerosene, diesel and other oil products, and can transmit the flow to the secondary meter remotely through the transmitter.
• Liquid Roots Meter consists of two parts: a housing and a counter. Customers can choose their own waist wheel flowmeter products according to the specific measuring medium.
• Liquid Roots Meter can be equipped with pointer counter and electronic digital display counter, which can be displayed on site or remotely controlled.

Specifications of Liquid Roots Meter

The header shows:	Pointer accumulation, zero return, pulse output, 4-20mA output, LCD display, communication output
Instrument model:	LL-11 display, 12 display plus signal, 13 signal output, H zero return, T high temperature, Y liquid crystal display
Measuring medium:	Liquid, various oils
Caliber specifications:	15—150
Flow measurement range:	0.25—250m3/h
measurement accuracy:	0.5 level 0.2 level
Temperature of the measured medium:	-20℃-100℃, maximum +200℃
Work pressure:	1.6MPa 2.5MPa 6.4MPa
output signal:	Pulse, 4–20mA
Communication type:	RS485
power supply:	DC12V—DC24V
Installation method:	Flange connection
Explosion-proof grade:	ExiaIIBT4
Protection level:	IP65

Extended Reading: Liquid Turbine Flow Meter

Flow Range（m³/h）

Diameter(mm)	Liquid viscosity (mPa.s) 2.0~150	Liquid viscosity (mPa.s) 0.6~2.0	Liquid viscosity(mPa.s) 2.0~150	Liquid viscosity(mPa.s) 0.6~2.0	Liquid viscosity(mPa.s) 2.0~150	Liquid viscosity(mPa.s) 0.6~2.0
25	0.6~6	1.2~6	1.2~6	1.5~6	1.5~6	2~6
40	1.6~16	3.2~16	3.2~16	4~16	4~16	5~16
50	2.5~25	5~25	5~25	6~25	6~25	8~25
80	6~60	12~60	12~60	15~60	15~60	20~60
100	10~100	20~100	20~100	25~100	25~100	33~100
150	25~250	50~250	50~250	60~250	60~250	80~250
Accuracy class	0.5 level		0.3 level		0.2 level

The main materials and nominal pressure are as follows:

Model	Shell, front cover, back cover	Cover	Rotor	axis	Shaft sleeve	Nominal pressure(MPa)
LL-AL	cast iron	cast iron	Aluminum alloy	stainless steel	Ball bearing	0.6、1.0、1.6
LL-EL	Cast steel	cast iron	Aluminum alloy	stainless steel	Ball bearing	2.5、4.0
LL-LL	Aluminum alloy	Cast iron/stainless steel	Aluminum alloy	stainless steel	Ball bearing	0.6、1.0、1.6
Remarks	Special contract can be specially designed

Extended reading: Liquid mass flow controller

LL-AL cast iron waist wheel flowmeter is widely used in the measurement of various oil products and liquid media that does not corrode cast iron materials.

LL-EL cast steel waist wheel flowmeter is used for the measurement of high pressure and low corrosive media.

The LL-LL cast aluminum light waist wheel flowmeter is suitable for the measurement of low viscosity, low pressure, and low corrosion (such as water, etc.) media.

Read more about: Liquid Flow Meters Guide

How does a Roots meter work?

Roots meter is also called waist flow meter. The working principle is the same as that of the oval gear flowmeter, and the structure is also very similar, except that the shape of the rotor is slightly different.

The rotor of the Roots meter is a pair of waist-shaped wheels without teeth. During the rotation, the two waist wheels do not directly contact and maintain a small gap. The driving is completed by the meshing gear that is sleeved outside the shell and coaxial with the waist wheel. This has obvious advantages compared with oval gear flow meters.

Oval gears have large meshing contact wear and are greatly affected by the cleanliness of the measured fluid. Easy to damage and reduce accuracy.

The Roots meter is linked by an additional drive gear, so there is no contact between the measuring elements during operation. Therefore, the wear during operation is very small, and high measurement accuracy can be achieved. It can keep the long-term stable parts of the flowmeter.

The structure of the waist wheel flowmeter can be divided into vertical and horizontal according to the working state:

The structure of the waist wheel includes a pair of waist wheels and a combined waist wheel composed of two pairs of waist wheels at an angle of 450 to each other.

The combined waist wheel flowmeter runs smoothly, which can greatly reduce the pressure fluctuation in the pipeline.

Generally, large-diameter flowmeters use vertical or horizontal combined waist wheels to reduce or eliminate pipeline vibration caused during flow measurement.

The rotor line of the waist wheel flowmeter is more reasonable, allowing the measurement of fluids containing tiny particles. Can be used for gas and liquid measurement. It is a positive displacement flowmeter that has been rapidly developed and widely used in recent years.

In addition to being used for industrial measurement, Roots meter is also used as a standard flow meter to calibrate other types of flow meters. The accuracy can reach ±0.1%.

Read more about: Positive Displacement Flow meter Technology

Types of positive displacement flow meter

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Sino-Inst, Manufacuturer for Liquid Roots Meters. For example: crude oil flowmeter, diesel flowmeter, gasoline flowmeter.

Sino-Inst’s Liquid Roots Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, US, and other countries.

PD Flow Meter is referred to as positive displacement flowmeter. Helical Gear-PD Flow Meter is also called, spiral double rotor flowmeter, LLT, LZ double rotor flowmeter or UF-Ⅱ spiral rotor flowmeter.

Features of Helical Gear-PD Flow Meter

1. Notable features such as no pulsation, extremely low noise, high precision, high reliability, large flow, and strong environmental adaptability.
2. The spiral rotor flowmeter can indicate cumulative flow, instantaneous flow, single flow, etc. on site.
3. It can output pulse signal, 4-20mA or 1-5V analog signal, 4-20mA+HART, MODBUS, support 232,485 communication, etc.
4. Combined with mechanical batch controller or electronic batch controller, it can realize various functions such as different types of filling and batch control.
5. The spiral rotor rotates at a constant speed in the metering cavity, and the flow is constant.
6. The spiral rotor rotates at a constant speed and the fluid pulsation is small.
7. The sending pulse is stable and accurate.
8. Various counters, speed regulators and external fine regulators can be configured.
9. Can be installed vertically (limited to DN200 or less, please specify when ordering)
10. It is suitable for thin oil, light oil, heavy oil, crude oil with large sand content and large water content, and the measured liquid has a large viscosity range.
11. The flow of liquid through the flowmeter is large, and the maximum flow is about twice that of an ordinary volume meter with the same diameter.
12. Long service life, high accuracy and strong reliability.
13. The internal pressure loss is extremely small.
14. The longest distance of wired remote transmission is 1000 meters, pulse signal output N=0.1L (one pulse is 1N), and it can be directly connected to the computer.
15. Intrinsically safe explosion-proof IaⅡCT6 (intrinsically safe type); explosion-proof dⅡBT6 (explosion-proof type); protection IP56.

Read more about Everything You Need To Know About Electronic Flow Meters

Specifications of Helical Gear-PD Flow Meter

Technical Parameters

Nominal diameter (mm)	8-400
Accuracy	0.2/0.5 level
Pressure loss	0-1000mPa.s‹80KPa; 1000-20000mPa.s‹150KPa
Nominal pressure	1.6, 2.5, 4.0, 6.4MPa
temperature range	-20℃-+80℃, +80℃+150℃, +150℃-+250℃
Medium viscosity	0-2000mPa.s
Ambient temperature	-30℃-+70℃
Connecting flange	GB9115.0719-2000 JB/TB2-94; It can also be manufactured according to user-specified flange standards
Photoelectric pulse (current) converter	Explosion-proof mark: ExdⅡBT4 ExdⅡBT4 (excluding acetylene)
Electronic counter	Explosion-proof mark: ExdⅡBT4 (without acetylene)
Protection level	IP65

Extended reading: Orifice Plate Flow Meter

Material selection

Model	Shell, front cover, back cover	Cover	Spiral rotor	Shaft	Shaft sleeve	Nominal pressure (MPa)
LLT-E	Cast steel	cast iron	Cast iron, aluminum alloy, stainless steel	stainless steel	Graphite, rolling bearings	Below DN100 -4.0 Above DN150-2.5
LLT-B、C	stainless steel	stainless steel		stainless steel		1.6、2.0、2.5
LLT-S	Double body type flowmeter; Specifications are DN80, DN100, DN150; Nominal pressure 6.3MPa, DN200 nominal pressure 4.0MPa
Note	The material of LLT-C is OCr18Ni12Mo2Ti; The material of LLT-B is OCr18Ni9Ti; Special requirements can be specially designed.

Flow range (m³/h)

Table 1, Accuracy 0.5

Model	Diameter	Viscosity mPa.s
		0.3~0.8	0.8~2	2~15	15~400	400~1000	1000~2000	2000~3500
		Petrol	Kerosene	Diesel, engine oil	Heavy oil	High viscosity liquids
LLT-0252	25	3~9	1.5~10	1~10	1~10	1~8	1~8	1~6
LLT-0401	40	3~9	1.5~10	1~10	1~10	1~8	1~8	1~6
LLT-0402		7~20	3~22	2.5~25	2.5~25	2~18	2~18	3~12
LLT-0501	50	7~20	3~22	2.5~25	2.5~25	2~18	2~18	3~12
LLT-0502		9~36	4.5~36	3.6~36	3.6~36	2.8~25	2.8~25	4.5~18
LLT-0801	80	9~36	4.5~36	3.6~36	3.6~36	2.8~25	2.8~25	4.5~18
LLT-0802		20~80	10~80	10~100	10~100	6.5~56	6.5~56	5~40
LLT-1001	100	20~80	10~80	10~100	10~100	6.5~56	6.5~56	5~40
LLT-1002		25~100	18~100	15~150	15~150	8.5~80	8.5~80	6.5~55
LLT-1501	150	25~100	18~100	15~150	15~150	8.5~80	8.5~80	6.5~55
LLT-1502		55~225	30~250	25~250	25~250	18~150	18~150	10~100
LLT-2001	200	55~225	30~250	25~250	25~250	18~150	18~150	10~100
LLT-2002		90~360	50~400	40~400	40~400	28~240	28~240	20~160
LLT-2501	250	90~360	50~400	40~400	40~400	28~240	28~240	20~160
LLT-2502		130~540	65~540	60~600	60~600	42~360	42~360	30~240
LLT-3001	300	130~540	65~540	60~600	60~600	42~360	42~360	30~240
LLT-3002		220~800	110~900	95~950	95~950	70~600	70~600	54~450
LLT-3501	350	220~800	110~900	95~950	95~950	70~600	70~600	54~450

Table two, Accuracy level 0.2

Model	Diameter	Viscosity mPa.s
		0.3~0.8	0.8~2	2~15	15~400	400~1000	1000~2000	2000~3500
		Petrol	Kerosene	Diesel, engine oil	Heavy oil	High viscosity liquids
LLT-0252	25	3.5~8	3~10	2~10	2~10	2~8	2~8	2~6
LLT-0401	40	3.5~8	3~10	2~10	2~10	2~8	2~8	2~6
LLT-0402		8~20	5.5~22	4.5~22	4.5~22	4~18	4~18	3~12
LLT-0501	50	8~20	5.5~22	4.5~22	4.5~22	4~18	4~18	3~12
LLT-0502		15~36	9~36	7~36	7~36	6~25	6~25	4.5~18
LLT-0801	80	15~36	9~36	7~36	7~36	6~25	6~25	4.5~18
LLT-0802		30~80	20~80	15~80	15~80	14~56	14~56	10~40
LLT-1001	100	30~80	20~80	15~80	15~80	14~56	14~56	10~40
LLT-1002		40~100	25~100	20~120	20~120	18~72	18~72	14~55
LLT-1501	150	40~100	25~100	20~120	20~120	18~72	18~72	14~55
LLT-1502		88~220	57~225	44~220	44~220	38~150	38~150	25~100
LLT-2001	200	88~220	57~225	44~220	44~220	38~150	38~150	25~100
LLT-2002		150~360	90~360	72~360	72~360	50~210	50~210	40~160
LLT-2501	250	150~360	90~360	72~360	72~360	50~210	50~210	40~160
LLT-2502		180~540	135~540	100~540	100~540	90~360	90~360	60~240
LLT-3001	300	180~540	135~540	100~540	100~540	90~360	90~360	60~240
LLT-3002		250~800	220~900	180~900	180~900	150~600	150~600	110~450
LLT-3501	350	250~800	220~900	180~900	180~900	150~600	150~600	110~450

Remarks: For special requirements, class 0.3 and class 0.1 flowmeters can be provided

Read more about: Industrial Oil Flow Meters

How does a PD meter work?

The flow meter is mainly composed of a body, a pair of spiral rotors, a magnetic coupling, a reduction mechanism, an adjusting gear, a counter and a signalling device.

The number of revolutions of the spiral rotor is transmitted to the meter head counter through a reduction mechanism composed of a magnetic coupling and a series of gears.

The magnetic coupling is mainly composed of active magnetic steel and driven magnetic steel. The use of magnetic coupling can increase the working pressure and working temperature of the flowmeter, ensure safe operation, and reduce maintenance work.

Extended reading: Positive Displacement Flow meter Technology

The measurement chamber mainly has a sealed cavity formed by a pair of special rotors and cover plates as the flow measurement unit.

The rotor is driven by the pressure difference between the inlet and outlet of the flowmeter to rotate, so as to continuously measure the liquid at the inlet to the outlet after being measured in the sealed cavity.

The amount of liquid flowing through each revolution is eight times that of the sealed cavity in the figure. The total number of rotor rotations and the speed of rotation are transmitted to the counting mechanism by the sealed coupling. Then there is pointer display and word wheel accumulation, you can know that it passes through the pipeline Total amount of liquid.

A pulse transmitter can also be installed in the counting mechanism, which becomes a flow meter with a signal.

Matching with the company’s electric display instrument, it can realize remote transmission (quantity, accumulation, instant and other functions) automatic measurement and control.

Read more about: Liquid Flow Meters Guide

Gear types of PD flowmeter:

SPUR GEAR

In Spur gear positive displacement flow meters, fluid travels around two round gears and is pushed through the meter’s internal chamber from inlet to outlet. The discrete volume of liquid trapped between each gear tooth is measured, as opposed to the Oval gear meter where a much larger volume between gears is swept through the chamber.

HELICAL GEAR

Possibly the most accurate PD meter in which two intersecting cylindrical bores are fitted with two interlocking helical screw-shaped gears. Because gear orientation is inline with flow, as the fluid passes through, the gears rotate with very little pressure drop. These flow meters are highly accurate over wide flow ranges and are compatible with very high viscosity fluids.

ROTARY PISTON

In this design a rotary piston oscillates in the circular internal chamber displacing a fixed amount of fluid with each rotation. This style accommodates ultra low flows and high flows, as well as high pressures.

Extended reading: Cylinder Gear flow meter for micro flow measurement.

More Featured PD Flow Meters

Sino-Inst, Manufacuturer for Helical Gear-PD Flow Meters. For example: crude oil flowmeter, diesel flowmeter, gasoline flowmeter.

Sino-Inst’s Helical Gear-PD Flow Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, US, and other countries.

Extended reading:
What is the K-factor in a flow meter?
Cryogenic Flow Meters|Liquid Nitrogen-Liquid Oxygen-LNG fluids

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Clamp-on Micro Flow Sensor

Strap on flow meter X3 is a kind of ultrasonic external clamp-on flow meter. Strap on flow meter X3 is easy to install. Suitable for measuring pipe diameter Φ9.53~Φ90.

Strap on flow meter X3 can meet the needs of different pipe materials: stainless steel pipe, carbon steel pipe, copper pipe, plastic pipe, PVC, PVDF, PPH, PPE, etc.

Strap on flow meter X3 almost meets the measurement of different clean fluids: various acids, alcohols, chemical solvents, alcohol, drinking water, Coca-Cola water… etc.

Product	Strap on Flow meter
Model	X3
Flow range	0.1m/s~5.0m/s
Accuracy	±2.0%
Repeatability	0.80%
Pipe size	φ6.35~φ90
Data storage	Daily, monthly, and Annual. Flow Totalizer
Analog output	4~20mA, Maximum load: 600Ω
Alarm output	DCT, Upper and lower limit alarm function(optional)
Communication	RS485,support Modbus communication protocol
Power supply	24VDC
Cable length	2.0m
Keypad	Four light touch buttons
Screen	OLED 128*64 displayscreen
Units	Metric and imperial units are available, Cubic Meters(m3), Liters(L), USA Gallons(GAL)/hour,/min,Default unit setting:m3/h
Totalizer	Six bit digit
Piper material	Stainless steel pipe, carbon steel pipe, copper pipe, plastic pipe
Case material	Aluminum alloy
Environment temp.	0℃~50℃（32°F~122°F)
Medium temp.	0℃~50℃（32°F~122°F)
Environment humidit	0-95% relative humidity, without condensation
IP Grade	IP54

Read more about: Strap on flow meter X3

More Featured Liquid Flow Meters

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Sino-Inst, Manufacuturer for Micro Flow Meters. For example: crude oil flowmeter, diesel flowmeter, gasoline flowmeter.

Sino-Inst’s Micro Flow Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, US, and other countries.

Positive displacement flow meter working principle

In principle, a positive displacement flow meter is a hydraulic engine that absorbs a small amount of energy from a fluid.

This energy is used to overcome the frictional force of the rotation of the flow detection element and the accessories, and at the same time form a pressure drop at the inflow and outflow ends of the meter.

The working principle of a typical Positive displacement flow meter (elliptical gear type) is shown in the figure.

The two OVAL gears have a special shape that rolls over each other for contact rotation.

P1 and p2 represent the inlet pressure and outlet pressure respectively, obviously p1>p2.

Figure 1(a) The lower gear rotates counterclockwise under the pressure difference between both sides, which is the driving wheel;
Because the pressure on both sides of the upper gear is equal, no rotating torque is generated. It is a driven wheel, driven by the lower gear, and rotates in a clockwise direction.

In the position in Figure 1(b), both gears generate a rotational torque under the action of differential pressure and continue to rotate.

When it is selected to the position of Fig. 1(c), the upper gear becomes the driving wheel, and the lower gear becomes the driven wheel, and it continues to rotate to the same position as Fig. 1(a) to complete a cycle.

One cycle action discharges the fluid volume of the four crescent-shaped cavities enclosed by the gear and the shell wall. This volume is called the “circulation volume” of the flowmeter.

Suppose the flow meter’circulation volume’ is υ, and the number of gear rotations in a certain period of time is N. Then the volume of fluid flowing through the flow meter in that time is V,

Then V=Nυ (1)

The rotation of the elliptical gear is transmitted to the counter through the magnetic seal coupling and the transmission reduction mechanism to directly indicate the total amount flowing through the flowmeter. If the sending device is attached, and then equipped with an electric display instrument, the remote transmission can only be instantaneous flow or cumulative flow.

Although there are many segmentation methods to form various forms of PDF, most of them have similar basic characteristics.

The main reason for the PDF error is the leakage of the gap between the movable measuring piece and the static measuring chamber that divides a single fluid volume.

One of the reasons for the leakage is to overcome the frictional resistance of the moving parts; the second is the pressure drop formed by the hydraulic resistance of the instrument.

Read more about: Positive Displacement Flow meter Technology

Positive displacement flow meter advantages and disadvantages

Read more about Mass Flow Rate vs Volumetric Flow Rate

Types of positive displacement flow meter

Positive displacement (PD) flow meters are volumetric flow measurement instruments. They are ideal for low flow rates, high viscosity fluids, and flow measurement involving start and stop or pulses.

Positive displacement flow meters are similar in design to gear pumps. However, the principle of operation is the opposite. It is not the gear that drives the fluid, but the fluid that drives the gear.

The non-intrusive Hall effect sensor detects the movement of the gear. When each gear tooth passes the sensor, a square wave pulse is generated and a discrete volume of liquid is measured. The pulse sequence generated is proportional to the actual flow rate and provides a highly accurate representation of the fluid flow.

There are many styles of positive displacement flow meters, and we provide three of them:

Extended reading: Stainless steel flow meters|304-316 optional

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FAQ

Sino-Inst, Manufacturer for Positive Displacement Flow Meters. For example crude oil flow meter, diesel flow meter, gasoline flowmeter.

Sino-Inst’s Positive Displacement Flow Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, the US, and other countries.

How to choose an asphalt flow meter? Liquid asphalt flow measurement has always been a difficulty. Liquid asphalt and other media that are easy to solidify and crystallize need to be measured with an oval gear flowmeter with heat preservation or heating function.

Features of Liquid asphalt flow measurement

Asphalt is solid at room temperature, but at a certain temperature, asphalt is liquid. And it is a liquid with high viscosity. It is usually measured by an oval gear flowmeter. It is especially suitable for measuring medium with high viscosity, and it is not sensitive to the change of the viscosity of the liquid being measured.

Liquid asphalt flow measurement

For the medium that is easy to solidify at normal temperature or easy to condense and crystallize at a certain temperature (for example: asphalt) in the pipeline, it is often necessary to heat the medium in the system pipeline to melt and keep the medium warm.

However, direct steam is not allowed at the place where the oval gear flowmeter is installed (to prevent damage to the flowmeter). For this reason, our factory has designed a flowmeter with insulation jacket for this situation. That is, an insulation jacket is added outside the flowmeter housing, and hot water, heat transfer oil or steam below 200°C can be used to pass into the insulation jacket. Melt the solidified medium in the flowmeter. And keep a certain temperature. So as to ensure the normal operation of the flowmeter.

Extended reading: Hot Water Flow Meters Improve Heating-Boiler System

The filter installed in front of the oval gear flowmeter can be in the form of a thermal insulation jacket, and the user can make special orders if needed. The nominal pressure of the insulation jacket is 0.5MPa.

Product performance standards

1. JB/T9242-1999 (General technical conditions for positive displacement flow meters)
2. JJG667-2010 (Verification Regulation of Positive Displacement Flowmeter)
3. JB/T79～80-1994, GB/T9112-2000 (standard for connecting flange)

Specifications of Thermal insulation Oval Gear flow meter

1. Accuracy: ±0.2%, ±0.5%
2. Nominal diameter: DN10～DN200
3. Nominal pressure: E cast steel 1.6～6.4MPa; B stainless steel 1.6MPa～4.0MPa
4. Temperature: normal temperature -20～100℃, high temperature +100～+200℃ (with radiator), please consult the manufacturer for higher temperature
5. Medium viscosity: 0.3 ～ 200mpa·s, 2000mpa.s or higher
6. Output signal: pulse, 4～20mA, 232, 485
7. Explosion-proof grade: ExiaIICT5, dIIBT4
8. Protection grade: IP65

Read more about Positive Displacement Flowmeter Technology

What flow meter is used for Liquid asphalt flow measurement?

Oval gear flowmeters are generally used to measure high-viscosity media such as liquid asphalt, with accurate measurement accuracy.

Of course, the Target type flowmeter can also be used to measure the Liquid asphalt flow measurement. The principle of differential target flowmeter is adopted to ensure the durability, practicability, and long service life of the asphalt flow meter.

Extended reading: Stainless steel flow meters|304-316 optional

The difference between target flowmeter and oval gear flowmeter

1. The difference in principle:

Oval gear asphalt flow meter is a positive displacement flowmeter. It uses mechanical measuring elements to continuously divide the fluid into a single known volume. The flow rate of the medium is measured according to the number of times that the metering chamber fills and discharges the volume of fluid successively and repeatedly. The accuracy can reach 0.5 level.

Extended reading: Cylinder Gear flow meter for micro flow measurement.

2. Different connection methods:

Target type asphalt flow meter can be made into clip type connection, pipe segment type connection, plug-in connection. Choose the appropriate connection method according to the size of the pipe diameter.

The oval gear asphalt flow meter can only be made into a pipe segment connection. If the pipe diameter is large, it is not recommended to choose an oval gear asphalt flow meter.

3. Differences in price:

Target type asphalt flow meter can choose carbon steel and stainless steel materials;
The oval gear asphalt flow meter can be made of cast iron, cast steel, and stainless steel.
In terms of the price of stainless steel, the two types of flow meters are much cheaper.

Due to the high temperature and high viscosity of asphalt media, high temperature and high viscosity protection is sometimes required. Both flowmeters can meet this requirement.

Read more about: Find your suitable industrial oil flow meter with best price

Oval Gear flow meter Troubleshooting

The following introduces the seven common faults and treatment methods of oval gear flow meters.

Oval gear does not rotate

The reason:

1. There is debris in the pipeline;
2. The filter is damaged and debris enters the meter, causing the gear to be stuck;
3. Due to excessive flow and wear of the bearings, the oval gears collide with the inner bore, causing the gears to jam.

Approach:

1. Clean the flow meter and pipeline;
2. Repair the filter;
3. Replace the bearing to ensure flexible operation of the gap.

The oval gear rotates, the pointer does not move or stops at all times

The reason:

1. The rotating fastener is sliding, damaged or inflexible;
2. The magnetic coupling slides;
3. The character wheel parts are stuck.

Approach:

1. Retighten the fasteners and remove inflexible parts;
2. Check whether the magnetic coupling is flexible and magnetic;
3. Eliminate the faults of the character wheel components.

Large negative error of flowmeter

The reason:

1. Leakage of bypass valve;
2. The inner wall or bearing of the oval gear metering is damaged or corroded by wear;
3. The flow is lower than the lower limit;
4. Magnetic coupling sliding or periodic obstacles in gear system;
5. The actual liquid viscosity is less than the detected liquid viscosity.

Approach:

1. Check the bypass valve;
2. Replace bearings, check gears, and adjust gaps;
3. Increase the flow;
4. Repair or replace the magnetic coupling or gear system;
5. Check the flow meter or make the viscosity correction by selecting the inspection liquid close to the actual liquid viscosity.

Large positive error of flowmeter

The reason:

1. The flow has large pulsation or contains gas;
2. The actual liquid viscosity is greater than the test liquid viscosity;
3. When the inlet valve is closed, the medium does not fill the metering chamber and is measured out.

Approach:

1. Reduce flow pulsation or increase gas separator;
2. Choose a test liquid with a viscosity similar to the actual liquid to inspect the flow meter or make a viscosity correction;
3. Use the flow meter outlet valve to control the medium flow.

The indicated value of the secondary meter is more than that of the primary meter

This fault is mostly caused by the vibration of the transmitting blade, which can be solved by appropriately adjusting the pressure of the damping plate on the blade.

The indicated value of the secondary meter is less than the indicated value of the primary meter

The reason:

1. The fastening screws at the sending blade are loose;
2. The transmitter dropped.

Approach:

1. Tighten the locking screw;
2. Adjust the gap between the transmitting blade and the transmitting device.

Secondary table does not indicate

The reason:

1. The line is open or short;
2. The transmitter is damaged.

Approach:

1. Check the line carefully;
2. Replace the transmitter.

The oval gear flowmeter is mainly composed of a body, a pair of oval gears, a magnetic coupling, a speed reduction mechanism, a high-speed gear, a counter and a signaling device.

In general, the possible failures of the flowmeter can be found in the above description and the corresponding reasons and treatment methods.

If the cause cannot be found for a certain fault, the manufacturer of the flowmeter can find a solution.

Extended reading: Mechanical flow meter types

More Featured Bitumen/Asphalt Flow Meters

In addition to the oval gear flowmeter is commonly used Bitumen/Asphalt Flow Meters. In fact, other flowmeters can also be selected. Such as mass flowmeters, circular gear flowmeters, and the target flowmeters mentioned above.

Related Products

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Sino-Inst, Manufacuturer for Asphalt flow meters for Liquid asphalt flow measurement. For example: crude oil flowmeter, diesel flowmeter, gasoline flowmeter.

Sino-Inst’s Asphalt flow meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, US, and other countries.

Marine Fuel Flow Meter is a positive displacement flow meter specially used for measuring marine fuel oil (MFO). With the highest accuracy.

Oval Gear-Marine Fuel Flow Meter features

1. The measurement has nothing to do with the fluid flow state. This is because the oval gear flowmeter relies on the pressure head of the measured medium to push the oval gear to rotate for measurement.
2. The greater the viscosity of the medium, the smaller the leakage from the gear and the metering gap. Therefore, the larger the sticky skin of the measuring medium, the smaller the leakage error, and the more beneficial it is to the measurement.
3. High measuring accuracy. It is suitable for flow measurement of high viscosity medium. But it is not suitable for fluids containing solid particles. Solid particles will jam the gears, making it impossible to measure flow. If the measured liquid medium contains gas, it will also cause measurement errors.

If the measured liquid contains solid particles and other impurities, you can install a filter first for filtering.

Further reading: Industrial LPG/Propane flow meter

Specifications of Oval Gear-Marine Fuel Flow Meter

Implementation standard of this product: JB/T9242-1999 “General Technical Conditions of Positive Displacement Flowmeter”, (JJG667-2010 Liquid Positive Displacement Flowmeter) Verification Regulations

Connecting flange standard: JB/T79～82-1994, GB/T9112-2000. ANSI and other flange standards can be customized

1. Working pressure (MPa): 0.6, 1.0, 1.6
2. Working temperature (℃): -20℃～+100℃, +100～+200℃
3. Medium viscosity (mPa.s): 0.6～200, 200～2000
4. Accuracy level: 0.5, 0.2
5. Caliber: DN10—200mm
6. Material: cast iron, cast steel, etc.
7. Display: It can indicate cumulative flow, instantaneous flow, single flow, etc. on site. It can also output pulse signal, 4-20mA or 1-5V analog signal, 4-20mA, MODBUS232, 485 communication, etc.
8. Explosion-proof grade: ExiaⅡCT5,dⅡBT4
9. Protection level: IP65

Model	Measured liquid viscosity  mpa·s
	<0.3	0.3~0.8	0.8~2		2~200		200~1000		1000~2000
LC-10		0.2-0.5		0.08-0.5	0.08-0.5	0.05-0.5	0.06-0.3	0.03-0.3	0.03-0.2
LC-15		0.75-1.5		0.3-1.5	0.3-1.5	0.15-1.5	0.2-1.0	0.1-1.05	0.07-0.75
LC-20		1.5-3	1-3	0.5-3	0.5-3	0.3-3	0.4-2.1	1.2-2.1	0.15-1.5
LC-25	4-6	3-6	2-6	1-6	1-6	0.6-6	0.8-4.2	0.4-4.2	0.3-3
LC-40	9-15	7.5-15	5-15	2.5-15	2.5-15	1.5-15	2.1-10.5	1.0-10.5	0.7-7.5
LC-50	10-24	8-24	5-24	4.8-24	4.8-24	2.4-24	2.4-16.8	1.6-16.8	1.2-12
LC-B40、50	8-20	6-20	6-20	4-20	4-20	2-20	2.8-14	1.4-14	1.0-12
LC-65	27-40	20-40	15-40	8-40	8-40	4-40	5.6-28	2.8-28	43151
LC-80	40-60	30-60	20-40	12-60	12-60	6-60	8.4-42	4.2-42	43189
LC-100	67-100	50-100	34-100	20-100	20-100	10-100	14-70	6-70	5-50
LC-150	127-190	95-190	64-190	38-190	38-190	19-190	26.6-133	13.3-133	9.5-95
LC-200	227-340	170-340	114-340	56-340	56-340	34-340	23.8-238	23.8-238	17-170
Accuracy	0.5	0.5	0.2	0.5	0.2	0.5	0.2	0.5	0.5

Extended Reading: Petroleum Flow Meter

Note: When the viscosity of the measured liquid is higher than 2000mPa.s, a high-viscosity structure is adopted. It can be applied to 20000mPa.s or higher. The flow range and other parameters are negotiable.

Extended reading: Positive displacement flow meter working principle

More Featured Fuel/Oil flow meters

Read more about: Find your suitable industrial oil flow meter with best price

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Extended Reading: Guide and Selection for Diesel Fuel Flow Meters

Sino-Inst, Manufacuturer for Oval Gear-Marine Fuel Flow Meters. For example: crude oil flowmeter, diesel flowmeter, gasoline flowmeter.

Sino-Inst’s Oval Gear-Marine Fuel Flow Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, US, and other countries.

The heating oil flow meter is also called a heating oil flow gauge. It is a high-temperature mechanical fuel meter. A high-temperature type oval gear flow meter can be used as a heating oil flow meter. Can reach 60℃~200℃.

Specifications of Heating oil flow meter

The header shows:	Pointer accumulation, zero return, pulse output, 4-20mA output, LCD display, communication output
Instrument model:	LC-11 display, 12 display plus signal, 13 signal output, H return to zero, N high viscosity, T high temperature, Y liquid crystal display
Measuring medium:	Liquid, various oils
Caliber specifications:	10—200
Flow measurement range:	0.04-340 m3/h
measurement accuracy:	0.5 level 0.2 level
The temperature of the measured medium:	-20℃-100℃, maximum +200℃
Work pressure:	1.6MPa 2.5MPa 6.4MPa
output signal:	Pulse, 4–20mA, RS485
Communication type:	RS485
power supply:	DC12V —DC24V
Installation method:	Flange connection, threaded connection
Explosion-proof grade:	ExiaIIBT4
Protection level:	IP65

Diameter	Materials	Measuring range under different viscosity（m3/h）			Pressure MPa
		0.8～2mPa．s	2～8 mPa．s	8～200 mPa．s
DN15	Cast iron/cast steel	0.45-1.35	0.36-1.35	0.18-1.35	1.6/6.4
DN20	Cast iron/cast steel	0.9-2.7	0.48-2.7	0.36-2.7	1.6/6.4
DN25	Cast iron/cast steel	1.8-5.4	0.96-5.4	0.27-5.4	1.6/6.4
DN40	Cast iron/cast steel	3.6-13.5	2.4-13.5	1.8-13.5	1.6/6.4
DN50	Cast iron/cast steel	5.8-21.6	3.6-21.6	2.9-21.6	1.6/6.4
DN65	Cast iron	9.6-36	6-36	4.8-36	1.6/6.4
DN80	Cast iron/cast steel	15-54	9.6-54	7.2-54	1.6/2.5
DN100	Cast iron/cast steel	24-90	22-90	12-90	1.6/2.5

For higher temperature or higher viscosity liquid measurement, please contact our sales engineer.

Read more about Liquid Flow Meters Guide

Features of Heating oil

The heat transfer oil furnace uses heavy oil, a light oil, or combustible liquid as fuel. Heat transfer oil is the heat carrier. The circulating oil pump is used to force the liquid phase to circulate. The heat energy is transferred to the heating equipment. Then it returns to the reheated DC special industrial furnace.

Thermal oil is widely used in petrochemicals, textiles, printing, and dyeing, plastics, rubber, food processing, wood processing, asphalt heating, carton production, vegetable dehydration, baking varnish, casting sand mold drying, etc. It can also be used for baking, steaming, shaping, melting, and drying at ≤ 350℃.

Read More About: Common Types Of Heating Oil Tank Level Sensors

Heating oil flowmeters

What kind of flowmeter is good for measuring heat transfer oil? What are the main Heating oil Flow Meter types?

Heating oil flow meters are based on the temperature of the heat transfer oil on the customer site to select the corresponding heat transfer oil flowmeter.

Generally, vortex flowmeters and high-temperature oval gear flowmeters can be used for temperatures around 200 degrees.

Orifice flowmeters can be used for high temperatures, so as to ensure the durability, practicability, and long service life of the heat-conducting oil flowmeter. The advantages of the heat-conducting oil flowmeter are high measurement accuracy and good stability.

Suitable for all kinds of heat-conducting oil flow meters. The complete system of heat-conducting oil flow meters consists of flow sensors, intelligent liquid crystal heat totalizers, temperature and pressure compensation components and instrument valve components.

Explore Oil and Gas Flow Meters

Let’s briefly compare the advantages and disadvantages of heating oil flow meters:

Read more about: Find your suitable industrial oil flow meter with best price

Mechanical fuel flow meter

Mechanical flow meters are a type of flow meters that use arrangement moving parts to measure flow. The fluid passes through a series of gears or chambers (positive displacement or PD) or through a rotating turbine or rotor. The mechanical flowmeter is different from electromagnetic and ultrasonic in principle. Mechanical flow meters easily monitor liquid flow rates for water, fuels, viscous fluids, and more.

Read more about Mechanical flow meter types

high temperature flow meter

Sino-Inst supplies a variety of high temperature flow meters. Measure high temperature medium, including high temperature oil, high temperature gas, etc.
Below are some of the high temperature upper limits that several common flow meters can measure. You can choose the appropriate flowmeter type according to your own medium temperature.
Of course, high temperature flow meters are special customized products. You can consult Sino-Inst’s sales engineer for more details.

Flow Meters	High temperature measurement upper limit
Electromagnetic Flowmeter	180℃	356 ℉	453.15 K
Turbine flowmeter	150℃	302 ℉	423.15 K
Vortex flowmeter	350℃；400℃(Special customized)	662 ℉	623.15 K
Precession Vortex Flowmeter	80℃	176 ℉	353.15 K
Ultrasonic flowmeter	160℃	320 ℉	433.15 K
Gear Flow Meter	200℃	392 ℉	473.15 K
Oval gear flow meter	200℃	392 ℉	473.15 K
Rotameter	450℃	842 ℉	723.15 K
Coriolis mass flowmeter	350℃	662 ℉	623.15 K
Thermal Mass Flow Meter	220℃	428 ℉	493.15 K
Differential pressure flowmeter	800℃	1472 ℉	1073.15 K
Target flow meter	500℃	932 ℉	773.15 K

Extended Reading: Industrial petrol flow meters Types

More Featured Oil Flow Meters for Sale

Check More About: Featured 1 Inch Flow Meters

More Oil Flow Measurement Solutions

Sino-Inst is Manufacturer of High-Temperature Oval Gear Heating Oil Flow Meters. We supply more than 20 kinds of Heating oil Flow Meters. 60% oval gear flowmeters, and other types of flowmeters.

Heating Oil Flow Meters are mainly used for flow measurement of various oils.
It can measure even Crude oil, heavy oil, marine fuel oil, etc.

Extended Reading: Summary Of Crude Oil Flow Measurement Options

Heating Oil Flow Meters enable stable flow measurement. This greatly meets the measurement needs of many applications. Can be used from small to large tubes.

Sino-Inst’s Heating Oil Flow Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, the US, and other countries.

The entire team at Sino-Inst’s has received excellent training, so we can ensure that every client’s needs are met. For assistance with your product requirements, whether it’s aHeating Oil Flow Meter, level sensor, or other device, give us a call.

High viscosity flow meter is the flow meter measures the flow rate of viscous fluid flow. LCD display Oval Gear High Viscosity Flow Meter is an ideal for measuring diesel gasoline and other media.

High viscosity liquids

High-viscosity liquid means that the liquid is viscous and thick, which is different from general liquids and non-Newtonian fluids (mud, pulp). The activity is slow and it is very difficult to filter by simple methods.

What’s more, in addition to some dust, the liquid also contains colloidal particles that are not completely dissolved.

For example: solutions such as rubber, paraffin, cellulose acetate, viscose, polyacrylonitrile, paint and animal glue.

Read more about: Liquid Flow Meters Guide

Oval Gear High Viscosity Flow Meter

The oval gear flowmeter is particularly suitable for measuring high viscosity media. And it is not sensitive to changes in the viscosity of the liquid being measured.

The measurement of the oval gear flowmeter has nothing to do with the flow state of the fluid. The higher the viscosity of the medium, the smaller the leakage from the gear and the metering gap. Therefore, the greater the viscosity of the measured medium, the smaller the leakage error, which is more beneficial to the measurement.

Measurable medium:
Fuel, diesel, gasoline, heat transfer oil, hydraulic oil, kerosene, tar, petroleum, crude oil, asphalt, resin and other liquids. Especially suitable for the measurement of high viscosity liquids.

Model	LC-NA Cast Iron with high viscosity type	LC-NE Cast steel with high viscosity type
Nominal Pressure Mpa	1.6	6.4
Temperature Range ℃	-10~+80;  +100~+180
Accuracy	0.5    ;0.2
Nominal Diameter (mm)	Flow   range(m3/h)
	Viscosity
	200~2000 mPa·s
10	0.02-0.2
15	0.075-0.75
20	0.15-1.5
25	0.3-3
40	0.75-7.5
50	1.2-12
80	3-30
100	5-50
150	9.5-95
200	17.4-174

If you need to measure higher viscosity liquids. Please contact our sales engineer.

Extended reading: Flat Pressure Sensor for High Viscosity Fluids

Oval gear flowmeter display mode selection:

The oval gear flowmeter is a mechanical instrument, and the display can be mechanical or liquid crystal display. Make a reasonable choice according to the different requirements of users.

Of course, the oval gear flow transmitter can also be combined with the secondary instrument to form an oval gear flow meter.

Flow meters with LCD displays now occupy the vast majority of the flow meter market. This is because the LCD display can display instantaneous flow, cumulative flow and other information at the same time. Some flow meters with temperature and pressure compensation can even display temperature and pressure information. Such as vortex flowmeter.

How to choose a high viscosity flow meter?

You may often encounter some high viscosity flowmeter selection problems. For example: What flowmeter is used for viscosity above 10000?

Under normal circumstances, when we encounter high-viscosity media (such as glue, eye drops, asphalt, etc.), the first thing that comes to mind is that impeller-type flowmeters are not suitable. A positive displacement flow meter can be used. The positive displacement flow meter includes a waist wheel, an oval gear, etc.

Are they all suitable?

Below we will introduce several flow meters suitable for measuring high viscosity media:

How to choose a high viscosity flow meter?

When choosing a high viscosity flow meter, it is important to consider the type of fluid being measured, the required accuracy of measurement, the operating environment, and the desired features.

Sino-Inst offers a wide variety of high viscosity flow meters to meet these needs.

For example, when we select a high viscosity flow meter for you. We will generally confirm with you first:

1. Types of media
2. Medium viscosity
3. Pipe diameter
4. Flow range
5. Temperature and pressure
6. Installation dimensions
7. What signal output is required.
8. Material requirements, etc.

For fluids with a high viscosity , such as oil or molasses, a positive displacement flow meter is often the best choice. These meters work by measuring the amount of fluid that is displaced as it flows through the meter. This type of meter is very accurate, but can be expensive.

Sino-Inst also offers a variety of other high viscosity flow meters, including Coriolis flow meters and mass flow meters. These meters are less common, but may be the best choice for specific applications.

Extended reading: Hydraulic oil flow measurement solutions.

Measuring principle of Oval Gear High Viscosity Flow Meter

When the measured liquid enters the oval gear flowmeter through the pipeline. The pressure difference generated at the inlet and outlet pushes a pair of gears to continuously rotate. The liquid measured by the lunar cavity is continuously delivered to the outlet. The product of the number of revolutions of the elliptical gear and four times the displacement per time is the total amount of the measured liquid flow.

Therefore, it is not difficult for us to find from the measurement principle of the oval gear flowmeter that it relies on the pressure head of the measured medium to push the oval gear to rotate for measurement, and has nothing to do with the fluid flow state.

For fluids with solid particles, oval gear flowmeters are not suitable. Because the solid particles will jam the gears, the flow cannot be measured.

It should also be noted that the use of oval gear flowmeters is not recommended for media with gas in the liquid. Its measurement error will be quite large.

When we use oval gear flow meters to measure liquids with high viscosity, there is less leakage from the gap between the gear and the metering.

Therefore, the greater the viscosity of the liquid being measured, the smaller the leakage error, and the more beneficial it is for the measurement, the higher the measurement accuracy.
It can be said that the oval gear flowmeter is the best choice for measuring the flow of high-viscosity liquids.

Extended reading: Featured Hydraulic Flow Meters For Sale

Installation and use of Oval Gear High Viscosity Flow Meter

1. The oval gear flowmeter should be equipped with a filter, and the arrows on the two shells point to the same flow direction.
2. When the measured liquid contains gas, a gas separator should be installed before the flowmeter.
3. Regardless of whether the pipeline is installed vertically or horizontally, the oval gear shaft in the flowmeter is installed in a horizontal position. (That is, the dial should be perpendicular to the ground).
4. When the oval gear flowmeter is installed correctly, if it is difficult to see the reading, the counter can be turned 180° or 90°.
5. Before installing the new flowmeter, use a bamboo stick to push the gear from the exit several times. If it is found to be immobile, it can be soaked with gasoline. (Avoid memory deposits after factory inspection)
6. The throttle valve should be installed at the inlet of the flowmeter, and the opening/closing valve should be installed at the outlet. When using the opening/closing valve, it should be pneumatically operated slowly and not suddenly open.
7. It is strictly forbidden to use line sweeping steam to pass through the flow meter.
8. In continuous use, the flowmeter must be equipped with a bypass pipe.
9. Before installing the oval gear flowmeter, the pipeline must be flushed. When flushing, use a straight pipe section (instead of the oval flowmeter position) to prevent welding slag and debris from entering the flowmeter.
10. It is strictly forbidden to check the flowmeter composed of cast iron and cast steel with water.
11. When the flowmeter is in use, the flow rate shall not exceed the technical requirements. It is better for the flowmeter to work at 50~80% of the maximum flow.
12. If the measured liquid is chemically corrosive, a stainless steel flow meter or Ocr15Ni12MO2Ti flow meter must be used.
13. The installation method of oval gear flowmeter is as shown in the figure.

More Liquid Flow Measurement Solutions

Sino-Inst is a manufacturer of LCD Display Oval Gear High Viscosity Flow Meter. We supply over 20 High Viscosity Flow Meters. Oval Gear Flow Meters are one of the most commonly used. Because it can choose cast iron, cast steel, stainless steel and other materials. Can meet the needs of a variety of measurement media. At the same time, it can be configured with ordinary mechanical display or LCD smart display, output pulse or 4-20mA signal. Can meet the needs of most users.

The LCD Display Oval Gear High Viscosity Flow Meter has high measurement accuracy. The basic error is generally ±0.5%R, and can be ±0.2%R or higher in special cases. Especially suitable for use in the field where high precision measurement is required.

The LCD Display Oval Gear High Viscosity Flow Meter has no influence on the metering accuracy when measuring the flow field distortion of the rotating flow and the pipe baffle, and has no requirement for the straight pipe section in front.

LCD Display Oval Gear High Viscosity Flow Meter can be used for the measurement of high viscosity fluids. The flow range is wide, generally 10:1 to 5:1. Special up to 30:1 or greater.

Sino-Inst’s High Viscosity Flow Meters, made in China, have good quality, with better prices. Our High Viscosity Flow Meters are widely used in China, India, Pakistan, USA and other countries.

Sino-Inst’s entire team is well trained, so we can ensure that each customer’s needs are met. If you need any help with your product requirements, whether it is a High Viscosity Flow Meter, level sensors, or other equipment, please give us a call.

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