Gas Rotameter Tips

What is Gas Rotameter?

Rotameter is also called float flowmeter. It is often called glass tube float flowmeter, glass rotameter, metal rotameter, and metal tube float flowmeter.
Rotameter is mainly used to measure the flow of single-phase non-pulsating fluid (gas or liquid). When gas or liquid is introduced into a uniform conical flow tube. The float rises. Its weight is supported by the fluid flowing below. Until the entire fluid volume is available Flow through the float. The position of the float corresponds to a point on the pipe measurement scale and provides an indication of the fluid flow rate.

Gas Rotameter Tips

Can rotameter be used for gases?

Rotameter can measure gas.

Rotameter is a variable area flow measuring instrument commonly used in industrial automation process control, which can be used to measure the flow of liquid, gas, and steam.

Rotameters are especially suitable for dry gas and steam measurement. Such as the measurement of nitrogen, air, oxygen and other gases.

It is not applicable if the liquid medium or gas medium contains impurity particles. It will affect the accuracy of the measurement.

If the pressure is relatively large, you can use a metal tube float flowmeter. The metal tube float flowmeter can transmit signals remotely for total accumulation or flow control. You can also customize the remote metal rotor flowmeter according to your needs. Explosion-proof metal rotor flowmeter.

Further reading: Nitrogen(N2) Flow Meter Types

More Featured Gas meters:

Extended reading: Beginner’s Guide: Variable area flow meter

Air Rotameter

Metal tube rotameter can be used to measure air. Because the rotameter is a variable area flow measuring instrument commonly used in industrial process automation control.

Rotameter has the characteristics of small size, large detection range and convenient use. It can be used to measure the flow of liquid, gas and steam. It is especially suitable for medium flow measurement with low flow velocity and small flow. Therefore, there is no problem in measuring air. However, it should be noted that the metal tube rotor flowmeter is only suitable for the flow measurement of small-diameter and low-velocity media within DN200.

Extended Reading: Digital air flow meters

Rotameter is a variable area flow measuring instrument commonly used in industrial automation process control. It is mainly to measure the instantaneous flow of various liquid gases and steam under different working conditions. You can directly observe the value under the flow state of the medium. It can easily solve the problem of fluid flow measurement under various working conditions.

The metal rotor flowmeter has the characteristics of simple structure, large detection range, high temperature and high-pressure resistance, anti-corrosion, and explosion-proof. It has a wide range of applications in petroleum, chemical, metallurgy, electric power, medicine, food, sewage treatment, and other industries.

Read More about: Digital Rotameter

The common accuracy of the rotameter is 1.5. This accuracy has been able to meet the measurement needs of most users.

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

Yes. Rotameter can Be Used for Gases.

Rotameter is the most widely used variable area flowmeter type. Rotameters are called gravity flowmeters because they are based on the opposition between the downward force of gravity and the upward force of the flowing fluid.

When the flow is constant, the float stays at a position related to the volume flow. The position is indicated by a scale. Please note that in order to maintain the full effect of gravity, this dynamic balancing action requires a vertical measuring tube.

Other forms of gravity meters may include a piston or vane that responds to flow in a manner similar to the behavior of a float. All these devices can be used to measure the flow of most liquids, gases, and steam.

There are similar types that use springs instead of gravity to balance fluid flow. These do not need to be installed vertically, but corrosive or aggressive fluids can damage the spring and cause reduced accuracy.

Extended Reading: What is difference between rotameter and flow meter

Rotameters are generally divided into three categories: plastic rotameters, glass rotameters and metal rotameters according to the material of the tapered tube.

  • The former two are generally in-situ indicating type, and the latter is generally made into a flow transmitter.
  • According to different converters, metal rotor flowmeters can be divided into gas remote transmission, electrical remote transmission, indication type, alarm type, and integrated calculation.
  • According to the structure and purpose of the transmitter, it can be divided into basic type, jacket insulation type, anti-corrosion type, high temperature type, high pressure type and so on.

Extended reading: What is an air pressure transducer?

More about Types Of Air Flow Measurement Instruments.

Chlorine Gas Rotameter

Rotameters are used to measure the flow of various small-diameter media. Of course, it is also very reliable when used in the chlorine flow measurement industry.

For the measurement of chlorine gas, the metal tube rotameter can fully meet this measurement requirement. Rotameters are not only made of metal, but also made of glass.

Comparing the two, the metal tube rotor flowmeter has on-site display and intelligent remote transmission functions. The measurement accuracy is high and it is easy to use. And the whole is relatively sturdy and has a long service life.

The glass tube rotameter has a simple structure. There should be no bumps during use. It is fragile and non-explosive, and has a short service life. The metal tube rotameter is superior to the glass tube rotameter when measuring chlorine.

Extended reading: Gas Mass Flow Meter

The flow meters that can be used to measure chlorine are: rotameter, vortex flowmeter, differential pressure flowmeter, gas mass flowmeter, etc. Since chlorine is very corrosive, especially when there is moisture, it is necessary to consider anti-corrosion treatment.

Nitrogen Gas Rotameter

There are many types of Nitrogen gas flow meters. There are three types of flow meters commonly used to measure nitrogen. Precession vortex flowmeter, gas vortex flowmeter, thermal gas mass flowmeter. When selecting a model, it is necessary to select a suitable model and specification according to the parameters and cost that can be provided on-site.

Of course, the rotameter is also a good choice for measuring nitrogen. Because of the low cost.

Read more anout: Nitrogen Gas-Liquid Nitrogen Flowmeters

Hydrogen Gas Rotameter

There are three types of flowmeters commonly used to measure hydrogen flow: precession vortex flowmeter, gas vortex flowmeter, and thermal gas mass flowmeter. When selecting a model, it is necessary to select a suitable model and specification according to the parameters and cost that can be provided on site. You must communicate well with the sales staff to make the measurement accurate.

Of course, the rotameter is also a good choice for hydrogen measurement. Because of the low cost.

Extended reading: Featured Hydrogen flow meters

Natural Gas Rotameter

The flow measurement of natural gas is currently mainly used in trade settlement and is relatively common. my country’s natural gas trade measurement is based on the volume or energy method under the legally required quality indicators for transfer measurement. At this stage, volume measurement is basically the main method.

At present, the flowmeter products used for natural gas flow measurement generally include: gas waist wheel flowmeter, gas turbine flowmeter, precession vortex flowmeter, vortex flowmeter, ultrasonic flowmeter and orifice flowmeter.

Let’s make a simple comparison on the use of these flow meters.

Extended reading: 5 matters to pay attention to when choosing threaded Vortex Nitrogen Gas Flow Meter

Rotameter Gas Flow Conversion

When measuring gas and liquid media, are the parameters of the rotameter the same?

Metal rotor flowmeter is a variable area flow measuring instrument commonly used in industrial automation process control. When it is measuring liquid and gaseous media, because the density of the two media is different, the material of the rotor of the flowmeter will also be different due to the density of the medium.

Regardless of whether it is measuring gas or liquid, the metal rotor flowmeter is the same in appearance and structure. But because the density of a gas is lower than that of liquid, the density of gas rotor material is smaller than that of the liquid rotor.

Whether the rotameter for measuring gas or liquid, the structure is basically the same, and it is equipped with a rotor in a conical tube. The main differences are as follows:

  1. The calculated density of the rotor: the density for liquid is high, and the density for gas is low.
  2. Rotor shape: the cross-sectional area of ​​liquid is relatively small, and the cross-sectional area of ​​gas is relatively large
  3. Damping device: It is better to use a damping device for liquids and gas, so that the measured value is stable.

Therefore, when we choose the metal rotor flowmeter, we need to clearly describe the real-time conditions of the working conditions with the manufacturer. In this way, we can formulate qualified process and technical parameter models of flowmeters according to the actual requirements of the working conditions. So as to be able to solve the measurement problem more effectively.

Extended reading: Radar level sensor for solids – Dust solid level measurement

Gas Rotameter Calibration

It is not feasible to calibrate metal tube rotameters with conventional methods. This is determined by the structural principle of the transmitter.
Because the rotameter is between the input pressure source and the generated 4-20mA current signal. Besides to machinery and circuits. There are also micro-processing chips that perform calculations on input data. Therefore, the adjustment is different from the conventional method.

In fact, the manufacturer also has instructions on the calibration of metal tube rotameters. A series of transmitters produced by our company. For calibration, there are: “Set range”, “Re-quantity range”, “Fine adjustment” points.

Extended reading: liquid nitrogen level measurement

Among them, the “set range” operation is mainly to complete the configuration work through the number of LRV and URV. The “re-quantity range” operation requires the transmitter to be connected to a standard pressure source. Guided by a series of instructions, the transmitter directly senses the actual pressure and sets the value. The initial and final settings of the range directly depend on the actual pressure input value. But it should be seen that although the analog output of the transmitter has a correct relationship with the input value used. But, the value displayed by the digital readout of the process value will be slightly different. This can be calibrated by fine-tuning items.

Because each part of the metal tube rotor flowmeter needs to be adjusted separately and must be adjusted together. Therefore, the actual calibration can be carried out according to the following steps:

Make a 4-20mA fine-tuning first. It is used to calibrate the D/A converter inside the transmitter. Because it does not involve sensing components.

No external pressure signal source is required.

Do one more full fine-tuning. Make the 4-20mA and digital readings coincide with the actual applied pressure signal. Therefore, a pressure signal source is required.

Finally, do the re-quantification process. Adjust the analog output 4-20mA to match the external pressure signal source. Its function is exactly the same as that of the zero adjustment (Z) and range adjustment (R) switches on the transmitter housing.

Some people think that the range of metal tube rotameter can be changed as long as the HART handheld communicator is used. And can adjust the zero point and span. There is no need to enter a pressure source. But this approach cannot be called calibration, but can only be called “setting range”.

The real calibration requires a standard pressure source to enter the transmitter. The range adjustment (LRV, URV) is not calibration because the standard instrument is not used. Ignore the input part (pressure of the input transmitter) to adjust the output, (transmitter conversion circuit) is not a correct calibration.

Furthermore. The relationship between pressure and differential pressure detection components. A/D conversion circuit. And current output is not equal. The purpose of calibration is to find out the relationship between the three changes.

Extended reading: Cryogenic Flow Meters | Liquid Nitrogen-Liquid Oxygen

Metal Tube Rotameter

Metal tube rotameter with transmitter Metal tube rotameter with the transmitter is also called digital rotameter…

Extended reading: How does a rotameter work

Sino-Inst offers over 30 rotameter products. About 50% of these are for liquids. 40% are for gas. At the best price.

A wide variety of Gas Rotameter options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Gas Rotameters, located in China.

The top supplying country is China (Mainland), which supply 100% of the Float Flow Meter respectively.

Sino-Inst sells through a mature distribution network that reaches all 50 states and 30 countries worldwide. Gas Rotameter products are most popular in Domestic Market, Southeast Asia, and Mid East.

You can ensure product safety by selecting from certified suppliers, with ISO9001, ISO14001 certification.

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About KimGuo11

Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects. Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.