53b Irrigation protocol pressure calculation
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RT: Guys, I saw in the manufacturer’s instructions that the setting pressure for 53B is about 0.4 MPa higher than the pressure in the sealing chamber. How is this pressure in the sealing chamber calculated? The on-site solution is 11+53B flushing
The pressure in the sealed chamber is usually calculated based on the actual operating pressure of the pump; the outlet pressure of the pump or the operating pressure of the system can be used as a reference. The specific values need to be checked in the device’s technical specifications or confirmed with the manufacturer. Under the given 11+53B flushing scheme, if the operating pressure of the pump is known, for example 3 MPa, then the setting pressure for 53B should be the operating pressure plus 0.4 MPa, that is, 3.4 MPa. .
To convert the pump head into pressure, the following formula can be used: \ Where: – \( P \) is the pressure (in pascals, Pa), – \( \rho \) is the density of the liquid (1000 kg/m³ for water), – \( g \) is the acceleration due to gravity (approximately 9.8 m/s²), – \( h \) is the head (in meters). For a head of 115 meters, the calculation is as follows: \ Convert to megapascals (MPa): \ Therefore, if the pressure setting for the 53B flushing scheme is 0.4 MPa higher than the pressure in the sealing chamber, then the pressure setting for 53B should be: \ This is a theoretical calculation; in actual operation, other factors such as pipeline resistance must also be taken into account. It is recommended to consult the manufacturer or on-site technical personnel. .
The operating pressure is 1.15 MPa, while the sealing fluid pressure is only 0.8 MPa – that’s clearly not right
The end-face specific pressure must be provided by the sealing manufacturer, after which the pressure difference required for the desired head can be determined. Too low leads to external leakage, too high leads to internal leakage.
Hello, is it a centrifugal pump? According to API682 standards, it should be 0.14 Mpa higher than the pressure in the sealing chamber; moreover, the method for calculating the pressure in the sealing chamber varies depending on the pump design! Generally, it is the inlet pressure plus the pressure difference (which is related to the balance structure; impellers with balance holes typically have a pressure difference of 0.3 times the value, while multi-stage pumps with balance drums/disks usually have a pressure difference of 0.2–0.3 MPa. For VS4 submersible pumps, it is simply the inlet pressure)
I just felt that something was wrong, but I didn’t know how to calculate the pressure in the sealed chamber