Noise reduction device for natural gas metering system

The embodiment of the utility model provides a noise reduction device for a natural gas metering system. The noise reduction device comprises a conveying pipeline, wherein fluid to be conveyed circulates in the conveying pipeline; the ultrasonic flowmeter is arranged on the conveying pipeline; and the lambda-shaped pipe is arranged between the ultrasonic flowmeter and the pressure regulating device. According to the noise reduction device for the natural gas metering system, the lambda-shaped pipe is arranged between the ultrasonic flowmeter and the pressure regulating device, and the elbow, the three-way pipe, the blind sealing head and other pipe fittings in the lambda-shaped pipe are used for isolating a noise source, so that the lambda-shaped pipe has the effects of isolating noise and reducing noise; therefore, noise generated by the pressure regulating device is greatly reduced after being subjected to noise reduction treatment of the lambda-shaped pipe, it is ensured that the situation that the ultraso