WO2013071847A1

WO2013071847A1 - Split volute and water pump with the same

Info

Publication number: WO2013071847A1
Application number: PCT/CN2012/084457
Authority: WO
Inventors: 黄晓东; 陈晓飞; 魏志明; 谭建松; 任伟; 王旭兰
Original assignee: Huang Xiaodong
Priority date: 2011-11-15
Filing date: 2012-11-12
Publication date: 2013-05-23
Also published as: CN202360463U

Abstract

Disclosed in the present utility model are a split volute and a water pump with the volute. The split volute comprises a volute body, wherein the volute body is of a symmetric split die-casting structure. The water pump with the volute comprises the volute provided with the volute body, wherein the volute body is of a symmetric split die-casting structure. Compared with the prior art, as the volute adopts the symmetric split die-casting structure, the rejection rate of castings is reduced, the production cycle is shortened, and the size precision and the surface smoothness of the volute are improved, therefore the efficiency of the water pump is improved, and the expected purpose is achieved; and the evenness of the flow speed and less hydraulic loss of the water pump are realized by controlling the area of respective cross sections.

Description

Split volute and water pump having the same

Technical field

The utility model relates to the technical field of hydraulics, in particular to a volute and a water pump having the same.

Background technique

Centrifugal pumps are an ancient and widely used general purpose machine. Centrifugal pumps have many outstanding features compared to other types of pumps in terms of their principle, construction and operating performance. They can be manufactured in a wide range of flow rates and pressures, so they have a wide range of applications. The centrifugal pump mainly consists of two over-flow parts of the impeller and the volute. The volute is pure energy-consuming equipment, and the hydraulic loss can reach half of the total hydraulic loss of the pump. Therefore, the design and manufacture of the volute are good for the pump. Performance, especially its efficiency metrics, is extremely important.

The volute itself is merely a symbol of a loss and must not add any value to the total energy produced by the impeller. Therefore, in the design and manufacture of the pump body, it is essential to take all possible measures to reduce the loss in the volute to a minimum. It is well known that the hydraulic performance of a pump, especially hydraulic losses, is highly dependent on the flow conditions within the pump, which is closely related to the geometry and shape of the flow-through components.

After the water flow leaves the impeller, vortex and impact can be avoided in the volute only under the condition of free flow of external torque, and the hydraulic loss is reduced to a minimum. Theoretical analysis and experimental research have shown that the sufficient and necessary condition for the free flow of water in the volute is the conservation of the velocity moment of the flow, that is, the circumferential component of the absolute velocity of the fluid particle at any point in the volute and the point to the pump axis The product of the distance is a constant. When a certain section requires a constant flow rate, since the velocity moment on the section is constant, the geometry of the section cannot be arbitrary, and the geometrical elements of the section must satisfy certain specific relationships. The centrifugal pump is characterized by its working surface as a space-distorted surface. The design process has now reached the ideal result required by fluid mechanics by means of a computer. Therefore, the manufacturing precision and the cost problem become the impact of the pump. An important factor in the level of development.

The volute outlet chamber is generally composed of a volute having an irregular cross-sectional shape and a curved centerline of the flow passage, and a diffusing tube having a diverging cross section. After the liquid flows out of the impeller, it is collected and diffused by the outlet chamber and converts the kinetic energy into pressure energy with the least possible hydraulic loss, and is sent to the drain tank or the lower impeller. Therefore, the hydraulic performance of the outlet chamber will largely determine the technical perfection of the pump.

Based on the rough surface of the volute and impeller flow path manufactured by China's sand casting process, the geometric shape is unstable, which will inevitably increase the frictional resistance loss along the vortex flow path and the cause of boundary layer separation or secondary flow. A local resistance loss. If the artificial repair process is carried out, the surface layer with a certain hardness formed by natural solidification of the metal is destroyed, the anti-cavitation ability of the flow channel is reduced, and the service life is affected. In order to solve this problem, it is necessary to improve the surface finish of the flow path, reduce the amount of boring, preserve the casting surface of the flow path, and improve the process.

Summary of the invention

In view of this, the technical problem to be solved by the present invention is to provide a split volute with a simple manufacturing method and better performance.

In order to achieve the above object, the utility model is implemented by the following technical solutions:

A split volute comprising a volute body, wherein the volute body is a symmetrically split die cast structure.

Preferably, the volute body of the symmetrically split die-cast structure comprises a left volute and a right volute.

The utility model also provides a more efficient water pump with the volute, which is realized by the following technical solutions:

A water pump includes a scroll having a scroll body, wherein the scroll body is a symmetrically split die cast structure.

It can be seen from the above technical solutions that the beneficial effects of the present invention are:

Compared with the prior art, the utility model reduces the casting rejection rate, reduces the production cycle, improves the dimensional accuracy and surface smoothness of the volute, and improves the efficiency of the water pump by adopting the symmetrical shell die-casting structure of the volute. For the intended purpose, by controlling the area of each section, a uniform flow rate and a small pump hydraulic loss are achieved.

DRAWINGS

Figure 1 is a schematic view showing the structure of the left volute of the present invention.

Figure 2 is a schematic view showing the structure of the right volute of the present invention.

Figure 3 is a schematic view showing the structure of the water pump of the present invention.

detailed description

In order to enable those skilled in the art to further understand the features and technical contents of the present invention, refer to the following detailed description of the invention and the accompanying drawings.

Please refer to Figure 1 to Figure 3 As shown, the present invention provides a split volute comprising a volute body, wherein the volute body is a symmetrically split die cast structure. Wherein the volute body of the symmetrically split die-cast structure comprises a left volute 3 and a right volute 7 .

The utility model also provides a water pump with the split volute, which is realized by the following technical solutions:

More specifically, the left volute 3 of the pump in Fig. 1 and the right volute 7 in Fig. 2 are die-cast separately. When working, the pump passes through the right volute 7 The upper axial inlet is filled with water. Please refer to Figure 3. The pump drive shaft 1 is driven by external power. The impeller 11 is connected with the drive shaft 1 through the key 9. The impeller 7 The rotation of the water entering the water inlet enters the water channel formed by the docking of the left and right volutes, and then the water is discharged from the water outlet of the water pump.

The volute shell adopts a symmetrical split die-casting structure, the angle between the side walls of the volute is equal, the volutes on both sides of the impeller are spatially symmetrical, the area of all the volutes changes uniformly, the connection between the sections is smooth, and the sections are designed according to the section method. The section speed moments are equal; the impeller adopts the front curve and the swept type, and the turbine adopts the free-form surface modeling to optimize the design of the pump blades to meet the requirements of the high-efficiency and energy-saving water pump; the pump suction chamber straight-conical axial suction chamber, the structure of the suction chamber Parameter optimization design

As shown in Fig. 3, the left volute 3 and the right volute 7 are fixed by a suture bolt 4, and a sealing ring 10 is embedded in the left volute, mechanically sealed. 12 Installed in the seat hole of the left volute, the drive shaft 1 passes through the shaft hole of the mechanical seal 12, and the impeller 11 and the drive shaft 1 are connected by the key 9.

Left volute 3 and right volute 7 Casting separately, by controlling the cross-sectional area of the shaft, drawing each circle, the flow path of the pump is generated by free modeling, and the flow path and the impeller are optimally matched and designed.

According to the requirements of the design conditions of the pump, the straight cone axial suction chamber is optimized and the taper of the suction chamber is adjusted. The taper is adjusted to 12.5. °, to meet the energy-saving requirements of pumps.

One side of the blade is arranged on one side of the impeller, and the front curved and swept form is adopted. The blade is generated by free-form surface modeling and optimized design to meet the requirements of high-efficiency and energy-saving water pump.

The pump has high productivity and the production process is easy to mechanize and automate. Depending on the type of die casting machine, the average die-casting is 70 to 500 per hour. Pieces; high casting quality, casting accuracy IT11 ~ IT13, surface roughness Ra 6.3 ~ 1.6 μ m Generally, the die-casting parts can be directly used without mechanical processing; the mechanical properties of the castings are good. It is cooled in a metal mold and crystallized under pressure. The surface grain is fine and dense, and its tensile strength is 25% to 30% higher than that of sand casting. . The castings are complex in shape and can be directly cast into threads and teeth.

After the symmetrically split die-casting volute, the quality of the pump volute casting is significantly improved, the geometric accuracy and surface finish are improved by one level, and the overall quality of the pump is improved.

However, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the patent of the present invention. Therefore, equivalent structural changes made by using the specification and the drawings of the present invention are equally included in Within the scope of the present invention.

Claims

A split volute comprising a volute body, wherein the volute body is a symmetrically split die cast structure.
The split volute according to claim 1, wherein the volute body of the symmetrically split die-cast structure comprises a left volute and a right volute .
A water pump comprising a volute, characterized in that the volute is a volute according to claim 1.