Natural gas flowmeter is a very important equipment in natural gas volume measurement. According to the working principle of natural gas flowmeter, it mainly includes the following categories:

(1) Differential pressure flow meters mainly include orifice flow meters, Venturi flow meters, Annubar flow meters, etc. The orifice flowmeter has a simple structure and is currently one of the mature and commonly used methods for measuring natural gas. However, there are disadvantages such as low accuracy, relatively small range, and high requirements for the length of upstream and downstream straight pipe sections. The Anuba flowmeter can be used for measuring large-diameter natural gas with low pressure loss, but it is relatively expensive.

(2) Positive displacement flow meters mainly include waist wheel flow meters, dual rotor flow meters, etc. The waist wheel flowmeter and double rotor flowmeter have high accuracy and meet the length requirements of upstream and downstream straight pipe sections, making them suitable for measuring natural gas with small diameters and small flow rates.

(3) Velocity flow meters mainly include turbine flow meters, vortex flow meters, ultrasonic flow meters, etc. The structure of a turbine flowmeter is simple, highly reliable, and has relatively high accuracy and range, but it has requirements for flow rate and the length of upstream and downstream straight pipe sections. Spiral vortex flowmeter is not affected by pressure, temperature, and component changes, and its accuracy is average with a relatively small range. It is less commonly used in long-distance natural gas pipelines. Ultrasonic flowmeter is not affected by gas pressure, temperature, or component changes, with high measurement accuracy and a large measurement range (up to 100:1), and can achieve bidirectional flow measurement. But currently, most of the equipment is imported and expensive, only suitable for large and medium diameters, and not suitable for measuring natural gas with smaller diameters (less than DN100).

(4) Mass flow meter

The quality flowmeter has high precision and stability requirements for upstream and downstream straight pipe sections, and is suitable for measuring natural gas with small diameters and small flow rates.