The manufacturer tells you what the centrifugal pump pressure gauge has

Pressure is not a benchmark, but a derived force and area. Pressure gauge, also known as pressure gauge, is an industrial automatic instrument used to measure the pressure of gas or liquid. The pressure gauge of centrifugal pump can display and record the pressure value, and can also be attached with a control device. The pressure measured by the instrument includes: pressure, atmospheric pressure, positive pressure, negative pressure and differential pressure. Most engineering measurements are pressure gauges. The unit of pressure is Pa, and other units are: engineering air pressure, millimeter water column, etc.
The main principle of centrifugal pump pressure gauge measurement is as follows: use gravity and pressure balance, such as liquid column pressure gauge, piston pressure gauge measurement; The elastic pressure balance measurement method such as mechanical pressure gauge is adopted; Use pressure related pressure gauges to measure the pressure of other physical properties of substances, such as electronic pressure gauges.
Common liquid column pressure gauges include U-tube pressure gauge, single tube pressure gauge, inclined tube pressure gauge, etc. In practical application, there are many factors that will affect its accuracy, and some specific problems can be ignored - the main factors are environmental temperature change, gravity acceleration, capillarity, etc., which need to be corrected. In addition, it also affects the scale, reading and installation. Its advantages are convenient, simple, real and cheap. Commonly used in laboratories.
At present, commonly used mechanical pressure gauges include spring tube pressure gauge, diaphragm pressure gauge, bellows pressure gauge, etc. The elastic elements are spring tubes, diaphragms and bellows. Because the displacement caused by the deformation of the elastic element is very small, it is usually used as the angular displacement or electrical and pneumatic signals of the indicator for the convenience of display. It is simple, cheap and easy to use, and is widely used in industrial fields.
Installation and technical requirements for mechanical seal of centrifugal pump: technical requirements for machine, pump and mechanical seal accessories: the bending of shaft shall not exceed 0.05mm; All parts in the assembly meet the drawing requirements. When tightening the gland, after the coupling is aligned, tighten the compression screw to prevent the deflection of the flange face; The shaft vibration during mechanical seal installation shall not be greater than 0.1mm. The axial displacement of axis C shall not be greater than 0.5mm; The manufacturing tolerance of the shaft of the mechanical seal part is h8, and the finish is 1.6; The shaft end where the dynamic ring seal is installed and the gland end where the static ring seal is installed shall be chamfered; The installation of pump mechanical seal requires that the movable ring must be able to move flexibly on the shaft after installation.
The above is what the small editor of the centrifugal pump manufacturer told us about the centrifugal pump pressure gauge. I hope it can help you.

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