JPH0354398A - Centrifugal pump casing made of sheet metal - Google Patents

Abstract

PURPOSE:To minimize the deformation of the liner part of a casing even when excessive external force acted on a suction or a discharge flange by providing a reinforcing member connecting the suction flange and the discharge flange outside a casing shell. CONSTITUTION:Even when external force acted on a suction flange 10, this external force is absorbed by a reinforcing member 20, and the external force does not directly reach a casing shell 1. Therefore, deformation does not reach the casing shell 1, and securely avoid the contact of a liner ring 14 and the end part 5a of an impeller 5. Also, even when external force acts on a discharge flange 17, this external force is absorbed by the reinforcing member 20, and the external force does not directly reach the casing shell 1. Therefore, deformation does not reach the casing shell 1, and the contact of the liner ring 14 and the end part 5a of the impeller 5 can be securely avoided.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sheet metal centrifugal pump casing, and particularly to suppressing deformation of a part of the liner of the casing even when an external force is applied to the suction flange or the discharge flange. This invention relates to a sheet metal centrifugal pump casing that allows for

[Conventional technology]

Generally, a casing shell is integrally formed by deep drawing a single stainless steel plate or the like using a press, and a suction flange and a discharge flange having axes perpendicular to each other are fixed to this casing shell to form a spiral-wound pump casing. is known.

Since this type of centrifugal pump casing is made of sheet metal, it tends to be weak in strength, and when an external force is applied to the suction flange, this external force is directly transmitted to the casing shell, causing part of the liner to deform. There is a risk that this may occur. When a part of the liner deforms, it hits the impeller, which causes problems such as noise and pump overload, and even causes unexpected problems such as impeller damage due to contact between the casing shell and the impeller. This may lead to an incident.

In order to prevent this, conventionally, a partition is provided inside the casing shell to separate the suction chamber and the pressure chamber, and a part of the casing shell extending outside the partition is provided with a so-called flexible It has been proposed that a free structure is adopted, and when the above-mentioned external force is applied, only a part of the casing shell is deformed by the free structure, and this deformation does not extend to the partition body.

Also, from another point of view, a reinforcing member is stretched between the suction flange and the casing shell to create a so-called rigid structure, so that the external force acting on the suction flange is directly transmitted to the casing shell, and the casing shell itself A method has been proposed in which it is absorbed by the body.

[Problem to be solved by the invention]

However, the so-called flexible free structure has a problem in that when connecting the suction pipe to the suction flange, the suction pipe itself must be supported with another member to the foundation.

In addition, with a so-called rigid structure, there is no problem under normal conditions, but if an excessive external force that cannot be absorbed by the casing shell is applied to the suction flange, a part of the liner of the casing shell will deform, causing the above-mentioned problem. There is a problem that hits occur.

Furthermore, in the conventional structure, only the suction flange is protected in any case, and if the discharge flange is to be protected, similar measures must be taken for this discharge flange as well.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned problems of the conventional technology, and to minimize deformation of a part of the liner of the casing even when an excessive external force is applied to the suction flange or the discharge flange. An object of the present invention is to provide a sheet metal centrifugal pump casing that can be used.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a casing shell formed by deep drawing a steel plate into an integral shape, and a suction flange and a discharge flange having mutually orthogonal axes fixed to the casing shell. In the pump casing,
A reinforcing member for connecting the suction flange and the discharge flange is provided on the outside of the casing shell.

[For production]

According to the present invention, even if an external force acts on the suction flange,
Even if an external force acts on the discharge flange, in each case this external force will be absorbed by the reinforcing element and will not directly reach the casing shell. Therefore, even if an external force is applied, the casing shell will not be deformed, and contact between the liner ring and the end of the impeller can be reliably avoided, preventing unexpected accidents such as damage to the impeller. be able to.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a spiral pump casing made of sheet metal according to the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 indicates a casing shell of a centrifugal pump, and this casing shell 1 is formed by deep drawing a stainless steel plate or the like using a press. A fixed flan 2 is integrally formed at one end of the casing shell 1, and a suction boat 3 opens at the other end of the casing shell 1. This casing shell 1 is connected by a fixed flange 2 to a motor bracket (not shown) or the like.

A circumferentially extending volute chamber A is formed in the center of the inside of the casing shell 1, and the outer periphery of the volute chamber A is defined by an overhang 1a. This overhang 1a
is formed by bulging the outer circumferential wall of the casing shell 1 outward in the radial direction, and the height of the bulging is determined by starting the bulging from the middle and moving in the circumferential direction (counterclockwise in the figure), as shown in FIG. direction)
It rises continuously along the Therefore, the flow passage cross-sectional area of the volute chamber A gradually increases in the direction of fluid flow.

An impeller 5 is provided inside the casing shell 1 and is integral with a boss 6 , which is connected to the free end of the main shaft 7 . A shaft sealing device 8 is attached to the main shaft 7, and this shaft sealing device 8 is supported by a casing cover 9 fixed to the casing shell 1. A liner ring ↑4 for partitioning the suction side chamber and the discharge side chamber is disposed between the suction side end 5a of the impeller 5 and the casing shell {.This liner ring 14 has a substantially L-shaped cross section. is formed and pressed onto the inner peripheral wall of the casing shell 1.

A suction flange 10 formed by press is welded to the suction boat 3 of the casing shell 1, and a suction port 11 connected to the suction boat 3 is opened in the center of the suction flange 10. In addition, this suction flange 10
A sealing surface 12 for connecting a companion flange (not shown) is formed on the flange.

Further, as is clear from FIG. 2, one end of a nozzle 15 is connected to the terminal end 13 of the overhanging portion 1a of the casing shell 1, and a discharge flange 16 is integrally formed at the other end of the nozzle 15. has been done. The axis of the discharge flange 16 is orthogonal to the axis of the suction flange 10. A sealing surface 17 for connecting a companion flange (not shown) is formed on the discharge flange 16.
A discharge port 18 is opened in the center of the tube.

Further, according to this embodiment, a reinforcing member 20 bent into a U-shape for connecting the suction flange 10 and the discharge flange 17 is disposed on the outside of the casing shell (2). This reinforcing member 20 has two large through holes 26 and 27, one for the suction flange 10 and one for the discharge flange 17. The back surface of the discharge flange 17 extending outward through the through hole 27 is welded to the surface of the reinforcing member 20. This reinforcing member 20 is made of a material that is thicker than the casing shell 1, and since it does not come into direct contact with the fluid, an inexpensive material that is less corrosion resistant than the casing shell 1 is used.

Further, the reinforcing member 20 has the entire U-shaped side edge 21 bent inward to increase its rigidity, and the lower region of the reinforcing member 20 is formed as a pump leg portion 20a. A hole (not shown) for a mounting bolt is bored in the flat surface of the pump leg 20a. This reinforcing member 20
also functions as a receiver for a nut 22 used when connecting a companion flange (not shown), and is shown in Figs. 2 and 3.
As shown in the figure, this reinforcing member 20 has four bolt holes 23 on the side of the sealing surface 12 and also has four bolt holes 23 on the side of the sealing surface 17.
Four bolt holes 25 are drilled on the sides.

Next, the operation of the funnel-wound pump according to this embodiment will be explained.

A main shaft 7 is connected to a drive motor (not shown), and when the main shaft 7 is rotated, the impeller 5 rotates integrally with the main shaft 7, and fluid is sucked from the suction boat 3. This sucked fluid passes through the inside of the impeller 5, is given a centrifugal force, and is discharged into the volute chamber A from its outer periphery. This discharged fluid moves in the circumferential direction (counterclockwise in FIG. 2) inside the volute chamber A, passes through the nozzle 15, and then passes through the discharge flange 1.
It is discharged from the discharge port 18 of 6.

According to this embodiment, even if an external force acts on the suction flange 10, this external force is absorbed by the reinforcing member 20 and does not directly reach the casing shell 1. Therefore, even if an external force is applied, the casing shell 1 is not deformed, and contact between the liner ring 4 and the end 5a of the impeller 5 can be reliably avoided.

Moreover, according to this, even if an external force acts on the discharge flange 17, this external force will be absorbed by the reinforcing member 20, and the external force will not directly reach the casing shell 1. Therefore, as described above, the casing shell 1 is not deformed, and the liner ring 14 and impeller 5
It is possible to reliably avoid contact with the end portion 5a.

Furthermore, since the reinforcing member 20 that connects the suction flange 10 and the discharge flange 17 is bent into a U-shape and provided on the outside of the casing shell 1, the reinforcing member 20 is provided separately for both the suction flange 10 and the discharge flange 17. There is no need to provide one, and the structure can be extremely simple.

Further, if the pump legs 20a are formed in the lower region of the reinforcing member 20, it is convenient for installing the pump, and there is no need to add another leg, resulting in an even simpler structure.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, a suction flange and a discharge flange having axes perpendicular to each other are fixed to a casing shell integrally formed by deep drawing a steel plate using a press. In the pump casing, since the reinforcing member that connects the suction flange and the discharge flange is provided on the outside of the casing shell, even if an external force acts on the suction flange or an external force acts on the discharge flange, the reinforcing member connects the suction flange and the discharge flange. The external force is reliably absorbed by the reinforcing member and does not reach the casing shell, which can reliably prevent deformation of the casing shell, and can avoid contact between the liner ring and the end of the impeller. Unexpected accidents such as damage to the impeller can be reliably prevented.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a sheet metal centrifugal pump casing according to the present invention, FIG. 2 is a front view, and FIG.
The figure is also a plan view. 1...Casing shell, 3...Suction boat, 5...
Impeller, IO... Suction flange, 14... Liner ring, 17... Discharge flange, 20... Reinforcement member, 20a... Pump leg.

Claims (1)

[Scope of Claims] 1. In a spiral pump casing in which a suction flange and a discharge flange having axes perpendicular to each other are fixed to a casing shell integrally formed by deep drawing a steel plate, the suction flange A spiral pump casing made of sheet metal, characterized in that a reinforcing member for connecting the pump and the discharge flange is provided on the outside of the casing shell. 2. The sheet metal spiral pump casing according to claim 1, wherein pump legs are formed in the lower region of the reinforcing member.