Fluid resistance refers to the pressure drop of fluid flowing through pipes, valves or equipment. The actual process pressure gradually decreased. In order to ensure the final pressure required by the process, a pressure source (gas compressor or pump) is needed to provide higher pressure, that is, more energy is consumed. Therefore, the amount of resistance reflects the amount of energy loss. In oxygen production, flow resistance is also closely related to the production process. For example, the resistance measurement of switching heat exchanger is the basis to judge whether self-cleaning is good. If the resistance of the distillation column is too large, the normal distillation conditions will be destroyed.
The magnitude of resistance (i.e. energy loss) can be expressed by the pressure drop before and after the fluid flows through the vessel. For example, the gauge pressure at the bottom of the tower is 0.038 MPa, the gauge pressure at the top of the tower is 0.025 MPa, and the pressure drop through the tray is (0.038-0.025) MPa = 0.013 MPa. Therefore, the measurement of resistance is the measurement of the pressure difference before and after the fluid flows through the pipe or container. In terms of measurement principle, it is the same as liquid level measurement, and various differential pressure gauges can be used to measure flow resistance.
To measure the resistance of the equipment, the positive pressure pipe of the differential pressure transmitter must be connected to the upstream end of the air flow, and the negative pressure pipe must be connected to the pressure pipe to flow to the downstream end of the air flow. If you often switch the flow direction in the channel, and want to measure the resistance in the forward and reverse flow direction, please pay attention to the connection direction of the positive pressure chamber and negative pressure chamber of the transmitter.
