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The fully automatic air permeability meter for fabrics is used to measure the air permeability of various materials, such as textiles, clothing and non-woven fabrics. QINSUN is the manufacturer. Welcome customers to inquire.
Test method:
The air permeability requirements of different fabrics are very different. Even for the same fabric, due to different usage requirements, the pressure difference between the two sides of the fabric is often different. The properties of the fabric itself and the usage requirements are different, and different pressure drops are selected for testing.
The test method is to let the gas pass through the fabric with all the surface under a certain pressure difference, and test the airflow rate to get the air permeability of the fabric. Most clothing fabrics can be considered relatively scarce and the printing requirements for testing are relatatively low. At this low pressure level, it is common practice to use a vacuum pump to pump out air to achieve the required differential pressure, and read the gas flow from the flow meter.
The main technology of the digital fabric air permeability meter is the measurement of pressure and flow. Our instrument uses an orifice flowmeter to measure airflow and a U-shaped tube to measure air pressure. The orifice plate has been used as a flow meter for more than a hundred years and many national and international standards are promulgated with it as the headline. In narrow pipes, the orifice plate is used as a blocking plate for measurements and forces the flowing material to compress. When the pipe-filled liquid flows into the tube through the throttling section, the flow beam will form a local contraction at the throttling section, and the static pressure will decrease, so that a pressure difference will be created before and after throttlingsection, and the greater the liquid flow rate, the greater the pressure difference, the greater the pressure difference, so the flow rate can be measured according to the pressure difference. Opening plate
Whether it is an orifice throttling device or a venturi tube throttling device, the measurement method is based on the flow continuity equation (mass conservation law ) and Bernoulli's equation (law of conservation of energy), which is suitable for measuring constant airflow. When using a standard throttling device for flow measurement, the following conditions must be met:
(1) The measured medium fills the entire pipe section and flows along a round pipe with an inner diameter of not less than 50 mm; for the venturi tube, the tube diameter must not be less than 100 mm and not more than 800 mm.
(2) The flow in the pipeline is stable, or can even be considered stable (when the flow is stable, the flow rate and pressure at the same point do not change with time)
>(3) When the measured medium passes through the throttling device, the phase state remains unchanged (for example: the liquid does not evaporate, the superheated steam is still superheated, the gas dissolved in the liquid does not precipitate, etc.), and it exists in a single phase of. For media with a complex composition, it should only be used if the properties are comparable to those of a one-component media.
