Plastic pump housing consisting of an inner casing, an outer casing and filling material therebetween

Abstract

A pump housing made of plastic sections is provided. The housing includes a first casing that has a first side facing the region in which a pumped medium will flow, and a second casing that has a second side facing the environment. The pump housing's first casing and second casing are both dimensionally stable, with a space between the first casing and the second casing. A filler material such as a self-expanding foam may be provided in the space. The pump casings may be standardized components, and multiple casings may be assembled to form pump housings to suit a particular application.

Claims

1. A pump housing, comprising: a first casing; a second casing; and a space filling material, wherein the first and second casings are made of plastic, the first and second casings are configured such that when positioned adjacent to one another a space exists between the first and second casings, the space-filling material is located in the space between the first and second casings, at least one part of the pump housing is formed from a plurality of segments, each of the plurality of segments being formed from a pair of the first and second casings the plurality of segments have no undercuts, the plurality of segments are configured to be connected to one another by connection flanges, the plurality of segments includes at least two geometrically identical segments.

2. The pump housing as claimed in claim 1, wherein the filling material is a self-expanding foam.

3. The pump housing as claimed in claim 1, wherein the filling material is a composite material.

4. The pump housing as claimed in claim 1, further comprising: reinforcing elements configured to be located in the space between the first and second casings.

5. The pump housing as claimed in claim 1, wherein at least one of the first and second casings is made of a fiber-reinforced composite material which includes fibers and a matrix containing the fibers.

6. The pump housing as claimed in claim 5, wherein the fibers are at least one of glass, carbon, boron and aramid.

7. The pump housing as claimed in claim 6, wherein the matrix is made of a thermoplastic or thermoset plastic.

8. The pump housing as claimed in claim 1, wherein the pump housing includes plastic and metal components.

9. The pump housing as claimed in claim 1, wherein at least one of the first and second casings includes a fluid-impermeable coating.

10. The pump housing as claimed in claim 9, wherein the fluid-impermeable coating is an epoxy-resin.

11. The pump housing as claimed in claim 1, further comprising: reinforcing elements configured to be located in the space between the first and second casings, wherein the filling material is a self-expanding foam, and at least one of the first and second casings is made of a fiber-reinforced composite material which includes fibers of at least one of glass, carbon, boron and aramid and a matrix of a thermoplastic or thermoset plastic containing the fibers, and at least one of the first and second casings includes a fluid-impermeable epoxy-resin coating.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a housing according to an embodiment of the invention of a centrifugal pump.

(2) FIG. 2 shows a detail of the FIG. 1 embodiment.

DETAILED DESCRIPTION

(3) An embodiment of a housing according to the invention of a centrifugal pump is represented in FIG. 1. The housing is constructed from individual casings 1, 2, which are produced from a fiber-reinforced plastic, for example from glass-fiber fabric with epoxy resin or vinyl-ester resin. The individual parts of the casings are produced in a customary laminating process, with hand lay-up processes, transfer molding (RTM), reaction injection molding or vacuum infusion processes being particularly suitable for this. All of the processes are aimed at creating as far as possible an approximately 10 mm thick casing which is produced in a mold that is free from inclusions or bubbles. The side of the surface that is facing the mold becomes very smooth, for which reason it can be used without re-working, or with only little re-working, both as a surface for the pump chamber and as a contact surface between the casings. The opposite surface of the respective casing tends to be rough and does not need to be worked any further. The casings 1, 2 are connected such that the two rough sides face one another. The connection may in this case be of a releasable or permanent form. The cavity created between an outer casing 1 and an inner casing 2 is filled with a foam 3. This foam preferably bonds with the rough surface and expands without any further buildup of pressure. Polyurethane foam or epoxy-resin foam will preferably be used for this.

(4) The upper part of the housing is of a one-part design, while the lower part of the housing is made up of a number of segments 6. The segments 6 are cut to size so as to form the desired pump chamber 4, it having been ensured that the geometry of the individual segments does not need any undercuts, making production much easier. A sealing arrangement, which as and when required may be arranged in specially shaped sealing grooves, may be additionally provided between the individual segments 6. The connection of the segments may either take place releasably by screws or else non-releasably, for example by adhesive bonding.

(5) According to the invention, the segments 6 of the lower part of the housing may be designed such that identical parts can be used. For example, there are segments that are suitable for the periphery and segments that provide the pump chamber for individual pump stages. Depending on the number of pump stages, any number of the latter segments can be arranged between the former segments. The parts themselves may be produced identically in production. The upper part of the housing would then have to be produced suitably for each pump according to the number of stages. The upper and lower parts of the housing are advantageously provided with a seal and releasably connected to one another.

(6) Provided in the upper part of the housing are various inlays 8, which serve for the mechanical stiffening of the housing part. In the present exemplary embodiment, these inlays 8 are designed as 40 mm thick metal parts. The parts are exactly positioned, the respective position being chosen with a view to an advantageous distribution of forces occurring and the reduction of vibrations. The positioned inlays 8 are laminated in their position into the housing part before the segment is provided with the expanding foam. In a similar way, flanges 7 for connection to adjacent components are incorporated in the housing. These flanges are for example laminated as metal parts into a casing 1 and subsequently provided with possibly necessary bore holes.

(7) Producing the individual segments 6 in a laminating mold provides good fitting accuracy, which makes the fitting of split rings 5 in the pump chamber 4 much easier. Before the final assembly of the housing, the split rings 5 can be fastened in their respective position. These rings are then fixed in an accurately fitting and sealed manner in the finished housing.

(8) Fastening structures can be provided on the housing that is represented in FIG. 1, it being possible for these structures to be likewise supported by laminated-in metal parts. For example, the underside can be provided with standing feet, which are strengthened by a corresponding metal inlay in the segments 6 of the lower part of the housing.

(9) FIG. 2 shows the upper part of the housing of FIG. 1, consisting of the outer casing 1 and the inner casing 2. The intermediate space is filled with the foam 3. Various bore holes for fastening for example to the lower part are represented in this view of a detail.

(10) TABLE-US-00001 List of designations 1 outer casing 2 inner casing 3 foam 4 pump chamber 5 split ring 6 segment 7 flange 8 inlay

(11) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.