Oxygen Flowmeter

Appearance

The appearance of the inhaler should be smooth, with uniform color and clear, consistent patterns. It  must not have defects such as exposed base, delamination, bubbling, peeling, cracking, or whitening  that significantly affect the aesthetics.

Working Pressure 

The inhaler should function normally within the pressure range of 0.2MPa to 0.3MPa after pressure  reduction by the central oxygen supply system.

Flow Range and Basic Error 

The flow range of the inhaler is 1L/min to 10L/min (or 15L/min), with a basic error of ±4% of the  maximum indicated value.

Safety Valve Discharge Pressure 

When the output pressure of the inhaler rises to (0.17±0.05)MPa, the safety valve should automatically  discharge.

Inhaler and Oxygen Pipeline Terminal

The inhaler connects to the oxygen pipeline terminal with a quick-connect and disconnect fitting. After  connection, the joint should be well-sealed with no oxygen leakage.

Oxygen Output Connector 

The oxygen output is connected to a delivery tube via a tapered connector.

Flow Tube 

The flow tube of the inhaler should be colorless and transparent, with clear numbers and scales. The  minimum graduation value should not be greater than 1L/min.

Flow Adjustment

The flow adjustment valve of the inhaler should be easy to operate, with appropriate tightness; the  float in the flow tube should move flexibly and smoothly; rotating the flow adjustment valve clockwise  reduces the flow, and counterclockwise increases the flow, with markings indicating the direction. When  the flow adjustment valve is closed, there should be no oxygen output.

Sealing 

When the inhaler is subjected to a working pressure of not less than 0.4MPa at the input, there should  be no air leakage at any connection.

Humidification Bottle 

The humidification bottle of the inhaler should be colorless and transparent or translucent, with  markings for the highest and lowest liquid level indicators, and should be filled with an appropriate  amount of water. It should not crack under a pressure of (0.17±0.05)MPa.