Centrifugal pump (centrifugal pump) refers to a pump that transports liquids by the centrifugal force generated when the impeller rotates. It has a wide range of applications and is widely used in mining, electric power, steel, metallurgy, municipal and other industries. It can transport clean water and solid particles. Neutral mineral water and other similar sewage or corrosive liquids.
Classification of centrifugal pumps:
1. Classified by the number of impellers
(1) Single-stage pump: that is, there is only one impeller on the pump shaft.
(2) Multi-stage pump: that is, there are two or more impellers on the pump shaft. At this time, the total head of the pump is the sum of the heads produced by the n impellers.
2. Classified by working pressure
(1) Low pressure pump: the pressure is lower than 100 meters water column
(2) Medium pressure pump: The pressure is between 100 and 650 meters of water column
(3) High pressure pump: the pressure is higher than 650 meters water column
3. Classified by impeller suction method
(1) Single-side water inlet pump: single-suction pump, with only one water inlet on the impeller.
(2) Double-side water inlet pump: double-suction pump, there is a water inlet on both sides of the impeller. Its flow rate is twice that of a single-suction pump, which can be roughly regarded as two single-suction pump impellers placed back to back together.
4. Classification according to the joint seam of the pump casing
(1) Horizontal split pump: a joint seam is opened on the horizontal plane passing through the axis line.
(2) Vertical joint surface pump: The joint surface is perpendicular to the axis line.
5. Classified by pump shaft position
(1) Horizontal pump: the pump shaft is in a horizontal position
Horizontal centrifugal pump
(2) Vertical pump: the pump shaft is in the vertical position
6. Classified according to the way the water from the impeller is led to the press-out chamber
(1) Volute pump: After the water comes out of the impeller, it directly enters the pump casing with a spiral shape.
(2) Guide vane pump: Water enters the outer guide vanes after coming out of the impeller, and then into the next stage or into the outlet pipe.
Usually we say that a certain centrifugal pump is a multi-stage centrifugal pump, referring to the number of impellers. According to other structural characteristics, it may be a horizontal pump, a vertical combined surface pump, a guide vane pump, a high pressure pump, a single-side water pump, etc. So according to different terms, the name is different. In addition, it can also be classified according to the purpose, such as oil pumps, water pumps, condensate pumps, corrosion-resistant centrifugal pumps, circulating water pumps, etc.
7. Classified by installation height
(1) Self-filling centrifugal pump: The pump shaft is lower than the surface of the sump, and it can be started automatically without watering when starting.
(2) Suction centrifugal pump (non-self-filling centrifugal pump): the pump shaft is higher than the surface of the suction pool. Before starting, you need to fill the pump casing and suction pipe with water, and then drive the motor to make the impeller rotate at a high speed. The water is thrown out of the impeller by centrifugal force, and negative pressure is formed in the center of the impeller. The water in the suction pool enters the impeller under the action of atmospheric pressure. It is also subjected to the action of the high-speed rotating impeller, and is thrown out of the impeller into the pressurized water pipeline.
If you want to quickly select a centrifugal pump model, you can download the pump selection software, just fill in the flow and head, and the system will automatically match the corresponding pump model for you.
Picture of centrifugal pump specifications, models and parameters:
There is currently no standard for the specifications and model parameters of centrifugal pumps. Basically, each manufacturer names the centrifugal pump model by itself according to the meaning of the centrifugal pump model. There are few uniform models named by various manufacturers in the market. Even for individual products of the same model, the factory accessories of each manufacturer may not be universal. It requires centrifugal pump parameters, centrifugal pump pictures and centrifugal pump brand to determine whether centrifugal pump accessories are universal. The centrifugal pumps commonly used by Zoomlion include self-balancing multi-stage centrifugal pumps, multi-stage centrifugal pumps, single-stage single-suction centrifugal pumps, single-stage double-suction split centrifugal pumps, self-priming pumps, etc.
1. Single-stage centrifugal pump
Single-stage single-suction centrifugal pump, water enters the impeller from one side in the axial direction, and there is only one impeller, so it is called single-stage single-suction centrifugal pump. Its characteristics are that compared with mixed flow pumps and axial flow pumps, it has higher head, smaller flow, simple structure and convenient use.
The old pump models include BA and B single-stage single-suction centrifugal pumps. In the 1980s, our company, Zhonglian Pumps, according to international standards and the actual conditions of drainage and irrigation machinery, carried out research and development work on centrifugal pumps, and produced IR and IS Type single-stage centrifugal pump series products have been listed as national professional standards and industry standards.
2. Multistage centrifugal pump
Compared with single-stage pumps, the difference is that multi-stage pumps have more than two impellers, which can absorb and press water in multiple stages, so as to raise the water to a high position. The head can be increased or decreased according to needs. The number of levels. Multi-stage pumps are mainly used for mine drainage, urban and factory water supply. Agricultural irrigation is rarely used. It is only suitable for high-lift, small-flow high-mountainous water pumping to solve the difficulty of drinking water for humans and animals. There are two types of multi-stage high heart pumps: vertical and horizontal. The main models are D-type and DL-type multi-stage centrifugal pumps.
(1) The performance range of D-type multi-stage pump is flow rate 6.3～720 cubic meters/hour, head 16～600 meters, water inlet diameter: 50, 75, 100, 125, 150, 200 mm, of which 50～125 mm pump type is The high speed is 2950 rpm, and the speed of 150-200 mm pump type is 1480 rpm.
(2) Structural type D-type multistage centrifugal pump is horizontal multistage (2-12 stages), the impeller is single suction, and the pump body is segmented. When the first-stage impeller is double suction, it is represented by DS. When two speeds are specified at the same time, the low speed is represented by DA. The multi-stage centrifugal pump used for boiler feed water is represented by DG.
3. Self-balancing multi-stage centrifugal pump
The self-balancing symmetrical horizontal multi-stage pump is designed to meet the needs of users and accelerate the development of high-pressure multi-stage pump technology. It adopts advanced technology of similar foreign products combined with many years of design experience of our company, and uses the hydraulic model of high-efficiency and energy-saving products recommended by the country, according to API610 Standard research and development of high-efficiency and high-pressure multi-stage centrifugal pump products; in the industry's leading position in technology. It has the advantages of wide high-efficiency zone, wide performance range, good cavitation performance, few wearing parts, and convenient installation and maintenance. The high-pressure self-balancing segmental centrifugal pump has innovated the structure of the traditional multi-stage centrifugal pump, canceled the axial force balance mechanism of the multi-stage centrifugal pump, and adopted the D, DG type multi-stage centrifugal structure of the balance disc or the balance drum. The best alternative to pumps. Because there is no balance device, that is, the friction loss of the disc without the balance disc and the return loss of the balance, the pump efficiency is increased by 5-14% compared with the same type of multi-stage pump, and the balance disc and the balance disc seat caused by the failure of the balance device are completely solved. Various failures, such as the wear and tear of the rotor, or the seizure of the rotor, greatly extend the service life of the pump. Years of operation have proved that the performance of this product has reached the international advanced level of similar products
Self-balancing multi-stage centrifugal pump models and specifications are: DP type, DFP type, MDP type, DGP, DYP type and several types of self-balancing multi-stage pumps.
4. S series double-suction split pump
It is a double-suction centrifugal pump that feeds water from both sides of the impeller. Because the pump cover and the pump body are assembled by horizontal joints, it is also called a horizontal split centrifugal pump. Compared with single-stage single-suction centrifugal pump, it has high efficiency, large flow and higher head. However, it is large and heavy, and is generally used for fixed operations. It is suitable for medium-sized irrigation areas on hills and plateaus, as well as for factories, mines, and urban water supply and drainage.
Double-suction centrifugal pumps are available in S type, Sh type, SA type, and SLA type. The difference between S type and Sh type is that from the driving end, S type pump rotates in a clockwise direction, and Sh type rotates in a counterclockwise direction. . The SLB type is a vertical, easy-to-detach, double-suction pump.
The performance range of S-type pump is 160～18,000 cubic meters per hour, head 12～125 meters, inlet diameter 150～1400 mm, rotation speed 2950, 1450, 970, 730, 585, 485, 360 rpm.
5. Self-priming centrifugal pump
The self-priming pump is a single-stage single-suction centrifugal pump that produces self-priming by the special structure of the pump itself. It is called a self-priming centrifugal pump. Compared with ordinary centrifugal pumps, there are significant differences in the structure of the pump body: one is that the inlet position of the pump is increased, and sometimes a suction valve is installed; the other is that a gas-water separation chamber is set on the water outlet side.
The self-priming pump outside the pump is a self-priming device added to the pump, such as a vortex pump, a water ring vacuum pump, a jet pump, and a hand pump.
Compared with ordinary centrifugal pumps, self-priming pumps have compact structure and simple operation. It not only saves the trouble of filling a large amount of water before starting, but also eliminates the low valve of the inlet pipe, reduces the water inlet resistance, and increases the water output of the pump. , But the efficiency is 3% to 5% lower than that of ordinary centrifugal pumps of the same specification. Self-priming pumps are mostly used in light and small sprinkler irrigation units and pipeline irrigation units.
There are many types and specifications of self-priming centrifugal pumps, such as ZX type, ZW type, CYZ type and WFB type.
The meaning of centrifugal pump selection model:
The meaning of the model when selecting the pump type varies from manufacturer to manufacturer. Some are numbered according to the head and pressure, the impeller diameter, the nominal diameter of the inlet and outlet pipes, and the type number of the pump. For example, IS pump means cantilever single-stage pump, SH pump means double-suction split pump, XB pump means fire pump, etc. The main parameters of water pump flow and head are indispensable in pump selection.
Take, for example, the multi-stage pump that Changsha Zhonglian Pumps has been producing for 30 years:
Multistage pump model meaning
Reference to the meaning of other centrifugal pump models:
Example 1: 80Y-100×2 single-stage centrifugal oil pump
80-intake diameter mm
Y-Single Suction Centrifugal Oil Pump
100-single-stage head m
2-stage
Example 2: 80WQ(QW)P40-15-4 non-clogging submersible sewage pump
80 WQ(QW) P 40-15-4
│ │ │ │ │ └—-Pump motor (KW)
│ │ │ │ └———-Pump head (m)
│ │ │ └——————--Pump flow rate (m3/h)
│ │ └———————-Stainless steel material
│ └—————————-Submersible sewage pump
└—————————————The caliber of the pump represents the nominal diameter of the pump discharge (mm)
Example 3: ISG50-160(I)A vertical pipeline centrifugal pump
ISG 50-160 (I) A(B)
│ │ │ │ └—The impeller is cut for the first time
│ │ │ └ ——— Traffic classification, (I) is large flow,
│ │ └—————Nominal outer diameter of impeller (mm)
│ └————————Pump caliber (mm)
│ ┌ ISG vertical centrifugal pump
└————————┼ IRG type vertical hot water pump
Example 4: XBD10.4/5-50LG fire pump
XB D 5.0 / 5-50 DL
│ │ │ │ │ │┌DL vertical multi-stage fire pump, speed 1450r/min
│ │ │ │ │ │ │LG vertical multi-stage portable fire pump, speed 2900r/min
│ │ │ │ │ └┼ISG vertical single-stage single-suction fire pump
│ │ │ │ │ │TSWA horizontal multi-stage fire pump
│ │ │ │ │ │ISW horizontal single-stage single-suction fire pump
│ │ │ │ │ └GDL vertical multi-stage pipeline fire pump
│ │ │ │ └—-—The diameter of the pump (mm)
│ │ │ └———-—Flow rate (L/s)
│ │ └———————Fire pump pressure (head (50m))
│ └——————-——Electric
└——————————Fire pump
Example 5: 80D12×5 horizontal multistage centrifugal pump
80 D 12 × 5
│ │ │ └-Number of impellers
│ │ └—- Single suction head (m)
│ └—————Single-suction multi-stage segmented centrifugal pump
└———————-Suction port diameter
