Ultrasonic flowmeter

An ultrasonic flowmeter that measures a flow rate of a gas flowing through a flow path using an ultrasonic signal, the ultrasonic flowmeter comprising:

• a first ultrasonic element configured to transmit, as a first signal, an ultrasonic signal and receive, as a second signal, an ultrasonic signal;
• a second ultrasonic element configured to receive, as the first signal, the ultrasonic signal and transmit, as the second signal, the ultrasonic signal;
• a damping pipe defining a flow path;
• a first ultrasonic propagator arranged outside the damping pipe, configured to propagate the first signal and the second signal of the ultrasonic signal between the first ultrasonic element and the damping pipe;
• a second ultrasonic propagator arranged outside the damping pipe, configured to propagate the first signal and the second signal of the ultrasonic signal between the second ultrasonic element and the damping pipe;
• a flow rate measurement unit that measures a flow rate of the gas in the flow path defined by the damping pipe based on the first signal and the second signal of the ultrasonic signal transmitted and received between the first ultrasonic element and the second ultrasonic element;
• a housing that accommodates the first ultrasonic element, the first ultrasonic propagator, the damping pipe, the second ultrasonic element, and the second ultrasonic propagator;
• and
• a connection interface configured to connect to an external pipe to form a continuous flow path including a flow path of the external pipe and the flow path of the damping pipe,
• wherein the damping pipe is made of a resin material having a higher ultrasonic signal attenuation capacity than materials forming the first ultrasonic propagator and the second ultrasonic propagator.