The concept of the pump
A pump is used to increase the pressure of the liquid or gas. The gas or liquid pressurized generated than ordinary conditions more great driving force for promoting some mechanical device or gas or liquid as a tremendous force for various purposes. It is a device for moving a liquid, gas, or special fluid medium, which is a machine for the work of fluid.
The classification of the pump
There are various types of pumps, the classification is complex, the common classification methods as follows:
According to the way of applying pressure to the fluid, the pump can be divided into three types: displacement pump, power pump and electromagnetic pump.
1. The positive displacement pumps include reciprocating pumps and rotary pumps (or rotary pumps) two, the type of transmission is high pressure small flow.
2. The power pump is divided into two kinds of centrifugal pump and vortex pump, the conveyor type is low pressure and large flow.
3. The electromagnetic pump can be used to transport liquid good conductors.
According to the structure of the pump, it can be divided into single-stage pumps and multi-stage pumps.
According to the use of pump, it can be divided into heat pumps, metering pumps, chemical process pumps, test pumps, vacuum pumps, titanium sublimation pumps and so on.
According to the nature of conveying fluid, it can be divided into water pump, oil pump, air pump, acid pump, alkali pump, water pump, sewage pump, mud pump, sulphur pump, phosphate pump and so on.
According to the driving of the pump, it can be divided into manual pump, steam pump, electric pump, pneumatic pump, hydraulic pump, electromagnetic pump, steam turbine pump, diesel pump and so on.
According to the mechanical parts of pump work, it can be divided into gear pump, screw pump, plunger pump, diaphragm pump and so on.
The applications of the pump:
The pump is a general mechanical product in the mechanical industry.
Pump in industrial fluid treatment and daily life is mainly used for water, gas, oil, alkali liquid, emulsion, suspension and emulsion liquid elemental and metal fluid, can also be used for transporting liquid, gas mixture and liquid containing suspended solids.
In agricultural production, the pump is the most important irrigation machinery.
The fracturing pumps and mud pumps are important equipment in oil drilling. In chemical production, the pump is used to adjust the temperature in chemical and petroleum production equipment, except for the pressure flow of the fluid medium and the chemical reaction.
In mining and metallurgical industry, the pumps are mainly used for water supply and drainage.
In the power sector, thermal power plant, nuclear power plant, they mainly use water pump, condensate pump, circulating pump and ash pump, main pump, multi-stage pump, etc.
In the shipbuilding industry, the types and quantities of pumps used by ships are also varied.
We will use a large number of pumps in the city water supply and drainage, water steam locomotive, machine tool lubrication and cooling, the textile industry in the transmission fluid and dye bleaching, pulp paper industry in the transportation and food industry in the transportation of milk and sugar foods.
The mechanical seal of the pump
Because the pump is mostly conveying fluid medium, it has the characteristics of horizontal installation, and it has the characteristic of high speed and high pressure and solid particles and corrosive. Therefore, the mechanical seal of the pump is usually required to resist the erosion of solid particles and the high speed of the sealing surface, the influence of the high pressure on the parameters of the sealing parameters and the corrosion of the matrix structure. The mechanical seal material requires high sealing surface friction material with optional nickel base alloy, cobalt based alloy, silicon carbide, pressureless sintering and reaction sintering silicon carbide metal impregnated graphite, graphite filled PTFE, PTFE filled with glass fiber, three special two aluminum oxide ceramics and so on; The base material can be selected as 2Cr13 stainless iron, 301 stainless steel, 304 stainless steel, 316 stainless steel, 316L stainless steel, 904L stainless steel, PTFE and so on; The optional materials for spring compensation are HHS, 1Cr18Ni9Ti, 3Cr13, etc.
It is different from the mechanical seal of the cauldron, the sealing medium of pump mechanical seal is mostly liquid, solid liquid mixture and atmospheric pressure; The cauldron is used to seal high pressure gas or gas mixture, which can pose a serious threat to the environment and life.
The mechanical seal of pump is one of the most precise and complicated mechanical basic components, which is the key part of pump machinery. Its sealing performance and service life depend on many factors, such as selection, precision of machine, correct installation and use. There are many kinds of mechanical seals for pumps. Models vary, and its maintenance is difficult to discern and judge.