DE202018002730U1 - Shutter made of continuously fiber-reinforced thermoplastic - Google Patents

Abstract

Monolithic containment shell made of fiber-plastic composite, characterized in that the fiber-plastic composite of continuous reinforcing fibers and thermoplastic material is formed wherein reinforcing fibers continuously over a portion of the flange (1) along a portion of the central part (2) along a portion of the bottom (3) run.

Description

Subject of the invention

The invention relates to a containment shell made of continuous fiber-reinforced thermoplastic in monolithic construction.

Background of the invention

A growing awareness of environmental and employee protection over the years has led to ever stricter health and safety regulations in all industries. Especially in the operation of chemical and petrochemical plants, it is important to keep the escape of aggressive and toxic media as low as possible. A shortcoming of conventional centrifugal pumps here are the shaft seals. They can wear out and become leaky, causing the fluid to escape. Regular maintenance due to wear is costly and reduces the availability of the system.

Directive 2008/1 / EC "on integrated pollution prevention and control" lays down rules for the protection of the environment for certain industrial activities. It always requires the best available technology (BAT) for some plants and, among other things, severely limits pump emissions. In so-called BREF leaflets, which represent a compilation of the best available techniques, also sealless and thus completely leak-free, and maintenance-free pumps are listed. In sealless pumps, the motor either runs as a "wet runner" in the pumped fluid or is isolated from the fluid by a lock. In magnetic drive pumps, this separation is achieved by means of a containment shell, via which the torque is transferred by means of magnetic rotors. Compared to wet rotors, this design eliminates the risk that the motor windings come into contact with the fluid when the casing is damaged.

Magnetic clutch pumps rotate magnets on an outer rotor around the containment shell and transfer torque to a magnetized rotor inside the containment shell. The magnetic coupling is thus used to drive the pump and has the advantage that the pump and motor can be built in one unit without the need for a shaft or mechanical seal. The containment shell is usually subjected to an internal pressure.

If metallic containment shells (due to their chemical resistance are often Hastelloy) are used, the rotating magnetic field induces these eddy currents.

The mechanical drive power is converted into heat output of often several kilowatts which on the one hand reduces the efficiency of the pump, on the other hand is heated via the containment shell and the fluid.

It is therefore advantageous if the containment shell prevents the formation of eddy currents. Through the use of fiber-reinforced plastics (FKV) or ceramics, the induction of eddy currents can be almost completely avoided. Ceramics are brittle and expensive and can not be made thin-walled for gap-pot applications.

Since the transmittable power depends significantly on the size of the gap between the magnets of the inner and outer rotor, a small gap between the magnets of the inner and outer rotor and thus a thinnest possible gap shell is required to transmit the highest possible torque.

There is therefore a desire for simple, thin-walled split pots made of materials that lead to low or no eddy current losses, are also chemically resistant and less brittle and also manage without liner.

FKV are fiber-reinforced materials in which fiber materials are incorporated as reinforcing fibers in a plastic. They are characterized by high specific stiffness and strength at relatively low weight and depending on the combination of materials good chemical resistance and are therefore ideal materials for highly loaded containment shell applications. A distinction FKV with short, with long and continuous (endless) fibers. The classification results from the fiber length. Short fibers have a length of 0.1 to 1 mm, long fibers have a length of 1 to 50 mm, continuous fibers (continuous fibers) have a length of more than 50 mm. Continuous reinforcing fibers are used as roving in fiber-reinforced plastics. Components with continuous fibers achieve the highest stiffness and strength values. The fibers essentially absorb tensile and compressive loads, the plastic essentially absorbs the shear stresses. Typical Verstäkrungsfaser - types are ceramic, glass, carbon, aramid and basalt fibers.

In the case of cans, protective inner linings made of unreinforced or reinforced and chemically resistant plastics, so-called liners, are frequently used as an additional component or as an additional component.

Gap pots are known from the prior art, which consist of non-metallic materials.

DE 1 03 22 465 A1 describes a separating sleeve of a multi-part split pot construction, wherein openings of the separating sleeve sealingly rest against holding parts and fastening and sealing means sealingly connect the parts of the split pot construction with each other. The separating sleeve is formed as a tube section of a fiber-reinforced, multi-layered tube produced in winding technology.

Out DE 10 2009 033 111 A1 a containment shell is known, which consists of a cylindrical, non-metallic base body, wherein the connection geometry has in the region of the split pot bottom two perpendicular to the longitudinal axis extending end faces, which serve as sealing surfaces.

The DE 36 26 934 A1 relates to a can for a permanent magnetic coupling in which the can, at least in the region of acting between the drive magnet magnetic field of an inner metal tube and a metal tube supporting the cover of an electrically non-conductive material.

The EP 0 822 641 B1 discloses a canned motor in which a sleeve is provided between the stator and rotor to which an end plate of the same material is welded.

The DE 20 2017 005477.9 discloses a containment shell in a multi-part design.

In the known types of FKV-split pots high wall thicknesses are required to absorb the forces occurring can. In addition, the types require a liner.

Object of the invention

Object of the present invention is to achieve an improved construction of a split pot made of fiber-plastic composite.

Description of the invention

According to the invention this object is achieved by a monolithic construction of continuous reinforcing fibers in combination thermoplastic material as a matrix. Due to the special nature of the orientation of the reinforcing fibers in combination with the particularly long course of the reinforcing fibers and the combination of the reinforcing fiber with a thermoplastic material, can be made with very thin wall thicknesses, which also manage in the application without an additional protective inner lining. Also by the unnecessary inner lining results in a particularly thin-walled design of the containment shell.

According to the invention, reinforcing fibers extend endlessly along a partial section of the flange, further along a partial section of the central section, further along a partial section of the floor. Particularly advantageous is an embodiment of the invention in which the reinforcing fiber and further, extends back along a portion of the central part and further along a portion of the flange. Over this distance reinforcing fibers are endless. These reinforcing fibers are aligned in the section of the central part substantially in the axial direction. The fiber angle a, between reinforcing fibers in the region of the central part is more than 0 ° and less than 90 °. The fiber angle is defined here as the angle to the flange side. This design means that particularly high loads can be absorbed by the reinforcing fibers, the fiber winding process can be used for the production and that very thin-walled components can be produced. Reinforcing fibers also extend according to the invention endlessly (continuously) along a partial section of the central part, essentially in the circumferential direction and in a length of preferably at least the simple circumference of the central part. The fiber angle β between reinforcing fibers in the region of the central part is more than 120 ° and less than 180 °. The fiber angle β is defined here as the angle to the flange side. This design means that particularly high loads can be absorbed by the reinforcing fibers and thus thin-walled components can be produced.

In particular, the combination of the above-described continuously extending in the circumferential direction reinforcing fibers with the above-described continuously extending in the axial direction reinforcing fibers and the thermoplastic matrix according to the invention leads to the particularly advantageous design for split pots.

The application of the reinforcing fibers can, for example, be carried out particularly advantageously in the fiber winding process, in the fiber placement or tape laying process. The thermoplastiche plastic may, for example, PA, POM PE, PP, PC PSU, PES PEI, PVDF, PTFE, PPS, PEEK, PAI or PI be particularly advantageous because of the high chemical resistance and high operating temperatures PVDF, PPS or PEEK exposed.

In the context of the present invention, "continuous reinforcing fiber" is used to mean reinforcing fibers made of reinforcing fibers existing materials such as rovings or reinforcing fibers understood.

By "liner" is meant in the context of the present invention protective inner linings.

The term "fiber angle" between reinforcing fibers in the region of the central part is understood to mean the angle to the flange side.

In the context of the present invention, "thermoplastics", also called plastomers, are understood as meaning plastics which can be deformed (thermo-plastic) in a specific temperature range. This process is reversible, that is, it can be repeated as often as desired by cooling and reheating to the molten state, as long as not using the so-called thermal decomposition of the material by overheating.

• 1: Eine schematische Darstellung einer speziellen Ausführungsform der Bauart

The attached figure represents a specific embodiment of the invention, in which:

• 1 : A schematic representation of a specific embodiment of the type

1 shows the schematic representation of the continuously extending reinforcing fibers (4) where reinforcing fibers (4) endless along a section of the flange (1) , further along a section of the middle section (2) , continue along a section of the ground (3) and further back along a section of the midsection (2) and further along a portion of the flange (1) run. Over this stretch are reinforcing fibers (4) endlessly ahead. reinforcing fibers (4) are aligned in the section of the central part substantially in the axial direction. The fiber angle α (5), between reinforcing fibers (4) in a section of the middle section (2) is about 35 °. reinforcing fibers (7) Moreover, according to the invention run endlessly (continuously) along a partial section of the central part (2) in the circumferential direction, wherein the fiber angle β (6) between reinforcing fibers (7) in the section of the middle part is about 170 °.

LIST OF REFERENCE NUMBERS

(1)

flange

(2)

midsection

(3)

ground

(4)

reinforcing fiber

(5)

Fiber angle α

(6)

Fiber angle β

(7)

reinforcing fiber

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10322465 A1 [0013]
• DE 102009033111 A1 [0014]
• DE 3626934 A1 [0015]
• EP 0822641 B1 [0016]
• DE 202017005477 [0017]

Claims (6)

Monolithic containment shell made of fiber-plastic composite, characterized in that the fiber-plastic composite of continuous reinforcing fibers and thermoplastic material is formed wherein reinforcing fibers continuously over a portion of the flange (1) along a portion of the central part (2) along a portion of the bottom (3) run. Monolithic containment shell made of fiber-plastic composite according to Claim 1 , characterized in that also reinforcing fibers extend continuously in the circumferential direction over a portion of the central part (2). Monolithic containment shell made of fiber-plastic composite according to Claim 1 , characterized in that the fiber angle α (5) between reinforcing fibers (4) in the section of the central part (2) is more than 0 ° and less than 90 °. Monolithic containment shell made of fiber-plastic composite according to Claim 1 and 2 , characterized in that the fiber angle β (6) between reinforcing fibers (7) in the section of the central part (2) is more than 120 ° and less than 180 °. Monolithic containment shell made of fiber-plastic composite according to Claim 1 to 4 , characterized in that the fiber volume fraction in the fiber-plastic composite is more than 25%. Monolithic containment shell made of fiber-plastic composite according to Claim 1 to 5 , characterized in that the containment shell has no liner.

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