JPH0646040B2 - Pump piping connections - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to the structure of a pipe connection on the suction port side and/or discharge port side of a pump made of steel plate such as stainless steel.

BACKGROUND ART Conventionally, the structure of the pipe connection part of a pump made of steel plate has been
As shown in FIG. 1, on the discharge port side, a pipe connection flange 2 having a discharge port 2a is welded to the discharge opening of the peripheral surface 1a of the casing body 1, and a thick iron plate 3 is attached to the back side of the flange surface of the pipe connection flange 2.
is attached by welding.

On the other hand, on the suction port side, a suction flange 4 having a suction port 4a is welded to the suction opening of the suction side side portion 1b of the casing body 1, and a thick steel plate 5 having bolt holes 5a is welded to the back side of the suction flange 4.
In the figure, 6 is a suction partition plate, 7 is a volute inner wall having holes 7a around its periphery, 8 is a casing cover, and 9 is an impeller.

In the conventional example shown in FIG. 2, a suction short pipe 1 is connected to the suction connection portion of the pump casing 11 made of thin plate (steel plate).
A box support 15 is provided surrounding the pump casing 11, and is made up of a suction-side casing wall 11a, a connecting flange 13, and a support 14 extending between the connecting flange 13 and the pump casing 11. In the figure, reference numeral 16 denotes a casing end wall. (See West German Patent Publication No. 3517828.) In the above-mentioned conventional example, a thick steel plate is welded to the back side of the piping connection flange surface (see Figure 1), and although the strength of the flange flat surface is sufficient, it has the drawback of being expensive. Also, the suction-side connecting flange 13 is welded to the suction short pipe 12.
In the case of a structure in which the pipe is supported by a support 14 arranged outside the pipe (Fig. 2), the connecting flange 13 itself is made thick, so the entire structure must be made of a corrosion-resistant material, and the water passage (suction short pipe) 12 in the middle is also a separate part, which increases the number of steps and the cost.

The present invention has been made in consideration of the above points, and aims to provide a piping connection part for a pump that has a corrosion-resistant flow path, has high rigidity at the flange joint surface, and can prevent deformation due to external forces applied to the flange.

DISCLOSURE OF THE INVENTION In order to achieve the above object, the present invention provides a pump piping connection part having the following structure.

The flange body is made of steel plate, and the inner peripheral portion forming the water passage is extended toward the casing body side. The extension is attached to the inlet/outlet portion of the casing body by welding directly or via a cylindrical body. A plurality of bolt holes are drilled in the flange surface of the flange body, and the outer side is formed into a square shape and has an annular rib with a U-shaped cross section protruding toward the casing body side. The cross section of the annular rib is U-shaped.
a bolt hole corresponding to the bolt hole is provided at the bottom of the U-shaped portion;
The annular rib of the presser plate has a raised surface formed integrally with it on the inside thereof, the raised surface being in contact with the rear surface of the flange, and the annular rib of the presser plate has a raised surface formed integrally with it on the outside thereof, the raised surface being in contact with the rear surface of the flange.

The reinforcing flange has a cylindrical portion larger than the diameter of the inlet and outlet of the casing body, the flange side end of the cylindrical portion is expanded radially outward and joined to the outer cylindrical portion of the flange body, bolt holes corresponding to the bolt holes are provided in the expanded portion, and the casing side end of the cylindrical portion is shaped to conform to the shape of the casing body and welded, and is attached so as to abut against the bottom of the annular rib of the pressure plate.

The reinforcing flange is also characterized in that a rib is provided on a part of the cylindrical portion thereof to protrude outward.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 are cross-sectional views of a pump equipped with a conventional pipe connection portion, FIGS. 3(a) and 3(b) are plan and cross-sectional views of a pipe connection portion showing one embodiment of the present invention, FIG. 4 is a cross-sectional view of a pipe connection portion showing another embodiment of the present invention, and FIG. 5(a) is a cross-sectional view of a pipe connection portion showing another embodiment of the present invention.
1B is a plan view of the reinforcing flange and a cross-sectional view showing the attached state.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the mode for carrying out the present invention will be described with reference to the drawings. FIG. 3(a) is a plan view of a piping connection portion on the discharge side of a pump showing one embodiment of the present invention, and FIG. 3(b) is a plan view of the AO of FIG.
This is a cross-sectional view taken along line B.

In the figure, the flange body 21 is made of a thin corrosion-resistant steel plate, and has an inner peripheral portion 21 forming a water passage inside the flange surface (the surface where the opposing flanges abut) 21a.
b is the inlet/outlet port 22 of the casing from the flange surface 21a
The flange surface 21a is sealed and welded to the flange 21a via a substantially cylindrical discharge nozzle 25, maintaining a watertight seal. An outer cylindrical portion 21c extending toward the casing body 22 is formed on the outer periphery of the flange surface 21a, and this cylindrical portion 21c provides a rib effect and improves the appearance.

On the other hand, on the back side of the flange surface 21a, a relatively thick presser plate 23 extending to the outer periphery corresponding to the raised face (R.F. (raised face) portion) of a general flange is fixed from the outside of the inner periphery 21b of the flange main body 21 to the back side of the flange main body 21. The presser plate 23 has an annular rib 23R with a U-shaped cross section protruding toward the casing main body 22 at the middle of the raised face. The annular rib 23R has a flat bottom portion (bottom portion of the U-shaped cross section) 23b with bolt holes 23a drilled therein corresponding to the bolt holes 21d of the flange main body 21, and a flat bottom portion 23b on the radially inner side of the flat bottom portion 23b.
The flange body 21 has a cylindrical portion 23c extending to a height substantially equal to that of the outer peripheral cylindrical portion 21c, a square box-shaped portion 23d extending radially outward to a height substantially equal to that of the outer peripheral cylindrical portion 21c, and a rectangular box-shaped portion 23d extending radially outward from the upper end of the cylindrical portion 23c to a height substantially equal to that of the outer peripheral cylindrical portion 21c.
The inner peripheral portion 21b is in contact with the rear surface of the flange surface 21a.
and a rising surface 23e extending to the vicinity of the RF portion. This rising surface 23e constitutes the RF portion.

In the above embodiment, the discharge nozzle pipe 25 is a separate part from the flange main body 21, but the inner peripheral portion 21 of the flange main body 21 may be extended to the inlet/outlet port 22a so that the discharge nozzle pipe portion is formed integrally with the flange main body 21.

FIG. 4 is a cross-sectional view of a piping connection portion on the discharge side of a pump showing another embodiment of the present invention (a cross-sectional view taken along line AOB in FIG. 4(a)).

In this embodiment, the annular rib 23R has a rising surface 23e extending up to the vicinity of the inner peripheral portion 21b so as to abut against the back surface of the flange surface 21a, and also has a rising surface 23e extending outward from the upper end of the box-shaped portion 23d.
The outer cylindrical portion 21c is formed of a raised surface 23f that extends to the vicinity of the outer cylindrical portion 21c.
f constitutes the RF section.

Furthermore, a reinforcing flange 24 is attached to the back side of the flange main body 21 so as to abut against the flat portion 23b of the bottom of the presser plate 23. The reinforcing flange 24 has a cylindrical portion 24a larger in diameter than the inlet/outlet portion 22a of the casing main body 22. The cylindrical portion 24a extends toward the flange side (upward in the figure) to the height of the lower end surface of the presser plate 23, and its end is expanded radially outward and joined so as to be folded inside the outer cylindrical portion 21c of the flange main body 21. In this state, the expanded portion 24b abuts against the underside of the annular rib of the presser plate 23, and the expanded portion 24b has bolt holes 24c drilled therein corresponding to the bolt holes 21d and 23a. The casing-side (lower in the figure) end 24d of the cylindrical portion 24a is formed to fit the shape of the casing main body 22 and welded.

FIG. 5(a) is a plan view of the main part of the reinforcing flange 24;
5(b) is a cross-sectional view taken along the COD line in FIG. 5(a), and the dashed two-dot line is a cross-sectional view taken along the EOD line in FIG. 5(b). As shown in the figure, a rib 24e is formed on a part of the cylindrical portion 24a of the reinforcing flange 24, protruding outward.

With the above-described configuration, in the pipe connection portion shown in Fig. 3(b), the rising surface 23e of the pressing plate 23 abutting against the back surface of the flange surface 21a of the bolted flange body 21 acts as a reinforcing material. Also, in the pipe connection portion shown in Fig. 4, the rising surfaces 23e and 23f of the pressing plate 23 act as reinforcing materials.

The presser plate 23 has a bolt hole 23a formed on a flat surface 23b.
Since the annular rib 23R has a U-shaped cross section and is formed integrally with the bolts, when the bolts are tightened, a force acts between the bolts of the presser plate 23 to deform it, but the pieces of the box-shaped portion 23d act as ribs to prevent this deformation. Furthermore, when the bolts are tightened, a torsional force acts on the presser plate 23, but the pieces of the box-shaped portion 23d also have the effect of increasing the rigidity against this torsion.

Furthermore, the reinforcing flange 24 attached to the back side of the flange body 21 has the effect of preventing deformation due to external forces applied to the flange body 21. Furthermore, by forming ribs 24e on the cylindrical portion 24a of the reinforcing flange 24, the strength of the reinforcing flange 24 is further increased, improving the effect of preventing deformation.

In the above embodiment, the cylindrical portion 23c of the pressing plate 23
It is needless to say that the shape of the tube does not have to be cylindrical, and it may be any cylindrical body such as a polygonal tube.

Furthermore, in the above embodiment, the pipe connection portion on the discharge side of the pump has been described, but it goes without saying that the structure of the pipe connection portion can be similarly applied to the suction side of the pump.

As described above, the present invention provides the following excellent effects.

The flange body is made of steel plate, and the inner periphery forming the water passage is extended toward the casing body side and attached to the inlet/outlet opening of the casing body directly or via a cylinder.
The flow path can be made corrosion resistant simply by constructing the casing body or the casing body and the cylindrical body from a corrosion resistant material.

Furthermore, by attaching a pressure plate to the underside of the flange surface, the pressure plate has bolt holes in the flat bottom portion of the U-shaped cross section that correspond to the multiple bolt holes in the flange body, an annular rib formed in a square box shape on the outside, and raised surfaces that abut against the underside of the flange surface formed integrally on the inside or both the outside and the inside of the annular rib, so that the pressure plate not only acts as a reinforcement for the flange surface, but also the pieces of the square box-shaped portion act as straight ribs that prevent deformation between the multiple bolts and have the effect of increasing rigidity against torsion.

In addition, by attaching a reinforcing flange to the back of the flange body, which consists of a cylindrical section with a larger diameter than the inlet and outlet of the casing body, an extension section that extends the flange side end outward and has holes for bolts, and a casing side end that is formed to fit the shape of the casing body, deformation due to external forces applied to the flange body can be prevented.

Furthermore, by forming a rib on the cylindrical portion of the reinforcing flange, further deformation of the flange body can be prevented.

In addition, since it is possible to separate the liquid-contacting parts that come into contact with the pumped liquid, such as the flange body, from the non-liquid-contacting parts that do not come into contact with the pumped liquid, such as the pressure plate and reinforcing flange, the liquid-contacting parts can be designed with an emphasis on corrosion resistance, while the non-liquid-contacting parts can be designed with an emphasis on strength, making it easy to design for corrosion resistance and strength, and allowing the effective use of expensive materials with excellent corrosion resistance.

INDUSTRIAL APPLICABILITY As described above, the piping connection of the pump according to the present invention is characterized in that the flange body is made of steel plate, the inner peripheral portion which forms the water passage is extended towards the casing body and attached to the inlet and outlet portions of the casing body directly or via a cylindrical body, a plurality of bolt holes are drilled in the flange surface of the flange body, there is an annular rib which is formed into a square shape on the outside and has a U-shaped cross section which protrudes towards the casing body, bolt holes corresponding to the bolt holes are provided in the bottom of the U-shape of the annular rib, and a pressure plate which has an integrally formed raised surface which abuts against the back surface of the flange surface on the inside or on the inside and outside of the annular rib is attached so as to abut on the back side of the flange surface, and therefore it is suitable for use as a piping connection of a pump which requires corrosion resistance in the flow path and great rigidity on the flange joint surface and is subject to large external forces which may deform the flange.

Claims (4)

[Claims] [Claim 1] A pump casing equipped with a piping connection flange, characterized in that the flange body is made of steel plate, the inner peripheral portion forming the water passage is extended toward the casing body side and the extended portion is attached to the inlet and outlet portions of the casing body directly or via a cylindrical body, a plurality of bolt holes are drilled into the flange surface of the flange body, a circular rib with a U-shaped cross section that is formed into a square outer surface and protrudes toward the casing body side, bolt holes corresponding to the bolt holes are provided at the bottom of the U-shaped cross section of the circular rib, and a pressure plate with a raised surface that abuts against the back surface of the flange surface is attached to the inside of the circular rib so as to contact the back side of the flange surface. 2. A piping connection for a pump according to claim 1, wherein the annular rib of said pressure plate has an integrally formed raised surface on the outer side thereof that abuts against the back surface of the flange surface. [Claim 3] A piping connection portion of a pump as described in claim 1 or 2, characterized in that the reinforcing flange has a cylindrical portion larger than the diameter of the inlet and outlet of the casing body, the flange side end of the cylindrical portion is expanded radially outward to be joined to the outer cylindrical portion of the flange body, bolt holes corresponding to the bolt holes are provided in the expanded portion, and the casing side end of the cylindrical portion is shaped to conform to the shape of the casing body and welded, and is attached so as to abut against the bottom of the annular rib of the pressure plate. 4. A piping connection for a pump according to claim 1, 2 or 3, wherein an outwardly projecting rib is provided on a part of the cylindrical portion of the reinforcing flange.