EP2885544B1 - Weld-free pot volute casing - Google Patents

Description

The invention relates to a method for producing a pot for a pot spiral housing for a Getriebeturboverdichter, as well as a pot spiral housing for a Getriebeturboverdichter.

Compressors or fluid compressing devices are used in various industries for various applications involving compression or compression of fluids, especially (process) gases. Well-known examples of this are turbo compressors in mobile industrial applications, such as in exhaust gas turbochargers or in jet engines, or even in stationary industrial applications, such as gearbox turbo compressors for air separation.

In such - in its operation continuously working - turbo compressor, the pressure increase (compression) of the fluid is effected by an angular momentum of the fluid from entry to exit by a rotating radially extending blades having impeller of the turbo compressor is increased by the rotation of the blades , Here, i. In such a compressor stage, pressure and temperature of the fluid increase while the relative (flow) velocity of the fluid in the impeller or turbocharger wheel decreases.

In order to achieve the highest possible pressure increase or compression of the fluid, a plurality of such compressor stages can be connected in series.

As types of turbocompressors, a distinction is made between radial and axial compressors.

In the axial compressor, the fluid to be compressed, for example a process gas, flows in a direction parallel to Axle (axial direction) through the compressor. In the radial compressor, the gas flows axially into the impeller of the compressor stage and is then deflected outwards (radially, radially). With multi-stage centrifugal compressors, a flow diversion becomes necessary behind each stage.

Combined types of axial and radial compressors draw large volume flows with their axial stages, which are compressed to high pressures in the subsequent radial stages.

While usually single-shaft machines are used, in (multi-stage) Getriebeturboverdichtern (shortly below only gear compressor), the individual compressor stages are grouped around a large wheel, with several parallel (pinion) shafts, each one or two - realized as housing structures , the inflow and outflow to the compressor stages causing spiral housings recorded - run wheels (arranged on free shaft ends of the pinion shafts turbochargers), are driven by a large, mounted in the housing drive gear, a large wheel.

In the spiral housing (in cup-shaped design also referred to as pot spiral housing), i. in a cylindrical bore in the volute, in addition to the impeller, a spiral insert is inserted in such a way that a space enclosed by the spiral casing and the spiral insert, a so-called annular space, remains in the cylindrical bore axially at the end of the spiral insert, over which the fluid flows from Impeller coming - flows radially over an expanding cross-section. Via a system piping, such as a pressure nozzle tube arranged on the volute casing with a pressure nozzle flange arranged thereon, the fluid then flows from the annular space further away from the compressor stage.

Such a transmission compressor, a transmission compressor from Siemens called STC-GC, used for air separation, is out
http://www.energy.siemens.com/hq/de/verdichtung-expansion-ventilation/turboverdichter/getriebeturboverdichter/stc-gc.htm (available on 05.10.2012) known.

From the DE 10 2008 025249 A1 , of the EP 0 101 915 A2 , of the DE 44 16 497 C1 and the DE 10 2007 042529 A1 Each method for producing a pot for a pot spiral housing of the type mentioned or corresponding Topfspiralgehäuse are known.

The - the impeller receiving, the inflow or flow of the fluid to or from the compressor stage or the impeller causing - volute is usually executed, especially for small wheels, as welded or cast structures, the advantages - in the case of Schweißkonstruktion- in a short delivery time and simplified usability for high pressures and - in the case of the cast construction - in a high efficiency.

In a welded (pot) spiral housing whose components, namely pot, pressure nozzle tube, Druckstutzenflansch and collar, to the spiral housing or to the pot spiral housing, welded.

In particular, for the connection of the pressure nozzle tube to the pot but a complex weld preparation is necessary in the welded cup spiral housing, as well as this welded joint is a weak point in the Topfspiralgehäuse. After welding, the Topfspiralgehäuse then still low stress annealed and sandblasted, which the manufacturing cost further complicated and increases the manufacturing costs,

The invention has for its object to provide a pot spiral housing for a turbomachine, which is simple and inexpensive to produce and / or mountable.

The object is achieved by a method for producing a pot for a pot spiral housing for a turbomachine and solved by a pot spiral housing for a turbomachine with the features according to the respective independent claim.

According to the method for producing a pot for a pot spiral housing, it is provided that the pot is produced from a blank by a machining process.

In this case, "blank" means a workpiece, for example a substantially block-shaped solid material body, which - containing the finished pot - substantially unprocessed in terms of the shape and design of the finished pot produced. Only through the machining process, the pot then obtains its essentially finished shape and design.

By "produced by a machining process from the blank" is to be understood that the blank - introduced or clamped - for example, in a processing machine / center - there in a machining operation by the machining process, for example by turning, milling and / or drilling in the processing machine or in the machining center, is processed - and leaves the processing machine or center after the machining process as the substantially finished pot.

That is, the machining operation on the blank may be a single machining technique performed on the blank, such as turning, milling or drilling. Also, the blank - in the one machining operation - by two or more different machining techniques, for example, by turning and milling or by turning and drilling or by milling and drilling or by turning, milling and drilling, are processed.

Without prejudice to this cutting, the pot-producing machining process from the blank, the blank can be preprocessed or be, for example, forged, in particular forged by Anschmieden a partial body to a body. Also, without prejudice to this cutting, from the blank pot-producing machining operation, the pot can be post-processed or be, for example, by local Machining of outer and / or inner contour surfaces in the pot, such as an introduction of screwing and / or contact surfaces for additional components in a pot surface or a post-treatment of already created during the machining process screwing and / or contact surfaces.

Expressed differently or simplified, according to the invention, the pot is produced by machining in a machining operation from a blank.

The pot spiral housing has a pot produced by the method for producing a pot for a pot spiral housing.

Other components or components of the cup spiral housing, such as a plant piping or a pressure pipe, can then, in particular directly, be screwed on or with the pot.

As a result of the invention, it is possible to produce a weld-free pot (by pure machining from a blank in a machining operation) or a swirl-free pot spiral housing.

Due to the fact that according to the invention the pot or cup spiral casing can be made free of welding seams, the pre-processing or processing intermediate and post-processing steps, such as welding seam preparation, welding, annealing, sandblasting, otherwise necessary for the spiral casing welding constructions and weld inspection, eliminated.

Since according to the invention the pressure-bearing pot of the volute casing or the pressure-bearing volute casing is or will be free of welded components, its manufacture is simplified and also safe in process, as well as the pot or pot volute casing being extremely pressure-proof.

Also, manufacturing times and / or error influencing possibilities in the production of the pot and the pot or pot spiral housing produced are minimized by the invention, eliminating by the invention otherwise necessary pre / processing or Bearbeitungszwischen- and post-processing steps.

The pot, as well as the pot spiral housing, according to the invention is also extremely fast and inexpensive to produce, especially in the invention, only a single component, i. the blank to be processed on the machine or in the machining center in a machining operation.

It is also possible to use common normal steels and / or high-alloyed steels for the pot or cup spiral housing according to the invention. Such steels can be provided inexpensively.

By manufacturing technology in the invention possible compact design of the pot or the Topfspiralgehäuses the pot on a small, as well as inexpensive processing machine / center - and therefore also inexpensive - produced.

Also, the invention makes it possible to keep the impeller (impeller / impellers) and / or fluid flow / fluid flows unchanged when the pot is used, that is, previous components of such compressors can be used in combination with the invention.

In particular, the previous vulnerability in welded cup spiral housings, ie the connection of the plant piping or the pressure nozzle tube with the pot, as well as other weld-related weaknesses in welded cup spiral housings omitted in the invention, in particular the compound "pot / plant piping" can be realized via a screw connection of plant piping or discharge pipe with the pot as well as the other connections via appropriate fittings.

A required cross-sectional extension for pressure build-up and flow delay in a compressor stage can then be implemented in the plant piping or in the pressure nozzle tube.

Such, by the invention possible screw "pot / plant piping" then lies before a pressure build-up (and flow delay) in - formable as a diffuser - Druckstutzenrohr and is thus less burdened.

Also can be reduced by the invention, the number of components in the volute casing, so otherwise (to) welded other (on) components of the spiral housing, such as the collar, together by the invention or integrated with the pot from the blank in the be machined machining operation.

Preferred developments of the invention will become apparent from the dependent claims.

According to a preferred development, the machining production method is a turning, a milling and / or a drilling. That is, the machining process on the blank may be a single, carried out on the blank machining process technology, such as a turning, milling or drilling, also the blank - in the machining process - by two or more different machining techniques, such as by turning and milling or by turning and drilling or by milling and drilling or by turning, milling and drilling.

Furthermore, it is expedient to dimension the blank in its shape and / or dimension as possible to save material. That is, the blank should be sized in shape and / or dimension, that during the machining process as little as possible material is removed from the blank.

According to the invention, the blank in cross section has a substantially teardrop-shaped outer contour. In other words, the blank contour is a% circle followed by a rectangle. Starting from such a blank mold, little material removal occurs during the machining.

Such, in cross-section substantially teardrop-shaped blank can be prepared by forging a body to a substantially cylindrical body in a die.

According to a further preferred development, the pot is or is post-processed, for example by local (re) machining of an outer and / or an inner contour surface in the pot.

Thus, for example, in such a treatment for already in the machining process on the pot Verschraubungs- and / or contact surfaces, such as surfaces for additional, connectable thereto with the pot components, such as the plant piping or the pressure nozzle tube, special surface properties, surface textures and / or Surface designs are realized.

Also, by such post-processing of the pot only special screw and / or contact surfaces - with special surface properties, surface textures and / or surface finishes - for additional, connectable to the pot components such as the plant piping or the pressure nozzle tube, introduced on the surface of the pot become.

According to a preferred development, the pot spiral housing has a plant piping screwed to the pot, in particular a pressure pipe which is screwed to the pot, via which the inflow or outflow of the fluid of the turbomachine can be realized. This plant piping or this discharge pipe can be designed as a diffuser to achieve a flow delay and pressure increase there.

In a further preferred embodiment, the cup spiral housing according to the invention - installed as a receptacle for an impeller of a compressor stage and as a flow guide for a fluid in the compressor stage - in a Getriebeturboverdichter.

Furthermore, a gear box connection, for example a collar, for a gear or pinion shaft driving the impeller can be screwed to the pot of the cup spiral housing. About this gap creates an additional adjustment of Topfspiralgehäuses the pinion shaft axis on the gearbox. This adjustment option can optionally replace the previous adjustment in this respect via lock and support blocks, which is particularly advantageous in turbomachines without parting line (stretch pinion shaft).

The description given so far of advantageous embodiments of the invention contains numerous features that in the individual subclaims are partially reproduced in several groups. However, those skilled in the art will conveniently consider these features individually and summarize them to meaningful further combinations.

In figures, embodiments of the invention are shown, which are explained in more detail below. The same reference numerals in the figures designate technically identical elements. Arrows illustrate directions of movement of objects or elements.

FIG 1

einen Längsschnitt durch einen Teil einer Verdichterstufe eines Getriebeverdichters mit einem erfindungsgemäßen schweißnahtfreien Topfspiralgehäuse in Blockbauweise,

FIG 2

eine Seitenansicht eines erfindungsgemäßen Topfes für ein schweißnahtfreies Topfspiralgehäuse in Blockbauweise,

FIG 3

eine Draufsicht des erfindungsgemäßen Topfes des schweißnahtfreien Topfspiralgehäuses in Blockbauweise,

FIG 4

einen Längsschnitt durch den erfindungsgemäßen Topf des schweißnahtfreien Topfspiralgehäuses in Blockbauweise entlang der Schnittlinie IV-IV aus FIG 3,

FIG 5

eine Schnittdarstellung des erfindungsgemäßen Topfes des schweißnahtfreien Topfspiralgehäuses in Blockbauweise entlang der Schnittlinie V-V aus FIG 2,

FIG 6

eine Schnittdarstellung des erfindungsgemäßen Topfes des schweißnahtfreien Topfspiralgehäuses in Blockbauweise entlang der Schnittlinie VI-VI aus FIG 3,

FIG 7

eine Schnittdarstellung des erfindungsgemäßen Topfes des schweißnahtfreien Topfspiralgehäuses in Blockbauweise entlang der Schnittlinie VII-VII aus FIG 2,

FIG 8

eine schematische Darstellung eines Rohteils 3 für den erfindungsgemäßen Topf 2 für das schweißnahtfreie Topfspiralgehäuse 1 in Blockbauweise,

FIG 9

eine schematische Darstellung eines Rohteils für einen Topf für ein schweißnahtfreies Topfspiralgehäuse in Blockbauweise, welches keinen Teil der Erfindung darstellt,

FIG 10

eine schematische Darstellung eines Rohteils für einen Topf für ein schweißnahtfreies Topfspiralgehäuse in Blockbauweise, welches keinen Teil der Erfindung darstellt,

FIG 11

eine perspektivische Darstellung des Rohteils nach FIG 10 mit darin "eingepasstem" Topf 2.

Show it:

FIG. 1

a longitudinal section through a portion of a compressor stage of a gear compressor with a welded seam-free pot spiral housing according to the invention in block construction,

FIG. 2

a side view of a pot according to the invention for a weld-free pot spiral housing in block construction,

FIG. 3

a top view of the pot according to the invention of the welding seam-free pot spiral housing in block construction,

FIG. 4

a longitudinal section through the pot according to the invention of the weld-free pot spiral housing in block construction along the section line IV-IV FIG. 3 .

FIG. 5

a sectional view of the pot according to the invention of the weld-free cup spiral housing in block construction along the section line VV FIG. 2 .

FIG. 6

a sectional view of the pot according to the invention of the weld-free pot spiral housing in block construction along the section line VI-VI FIG. 3 .

FIG. 7

a sectional view of the pot according to the invention of the weld-free pot spiral housing in block construction along the section line VII-VII FIG. 2 .

FIG. 8

a schematic representation of a blank 3 for the pot 2 according to the invention for the weld free pot spiral housing 1 in block design,

FIG. 9

a schematic representation of a blank for a pot for a weld-free pot spiral housing in block construction, which does not form part of the invention,

FIG. 10

a schematic representation of a blank for a pot for a weld-free pot spiral housing in block construction, which does not form part of the invention,

FIG. 11

a perspective view of the blank after FIG. 10 with "fitted" pot 2.

Weld-free pot spiral housing in block construction for a compressor stage in a gearbox compressor
FIG. 1 shows a longitudinal section through a simplified illustrated part of a compressor stage 18 of a gear compressor 10 with a weld seam-free pot spiral housing 1 according to the invention with a manufactured by machining from a blank 3 pot. 2

The compressor stage 18 has a rotor or pinion shaft 19 rotating about an axis of rotation 22 and received in an axial bore 15 in the pot 2, at the one end of which is shown an impeller 20 is mounted.

In the region of the entry of the pinion shaft 19 into the pot 2, a screwed to the pot 2 (see, screws 21) gear box connection 8 in the form of a collar 8 is arranged on there axial end face of the pot 2.

The impeller 20 is by an axial inflow 12 by a fluid 11 (axially) flows and conveys the compressed fluid 11 radially outward into an annular space 23rd

After a further deflection 24, the fluid 11 flows from the annular space 23 into a collecting space 25, collects there and enters via a flow opening 16 and a diffuser opening 16 in the pot 2 in a plant piping 4 a.

The plant piping 4 has a diffuser formed, with the pot 2 screwed to a screwing 17 on the pot 2 Druckstutzenrohr 5 (in the circumferential direction dargstellt) with subsequent Druckstutzenflansch 6, via which the further compressed there fluid 11 leaves the compressor stage 18.

The collecting space 25 extending in the circumferential direction about the axis of rotation 22 is formed by means of the pot 2 and a spiral insert 7 inserted into a recess 9 or cylindrical bore 9 of the pot 2.

The - consisting of high-alloy steel - pot 2 is made by pure machining in a single machining operation in a machining center of a forged stock 3.

The outer surface of the blank 3 is in the machining process - depending on the shape of the blank 3 - turned off on the outer contour of the pot 2, milled and / or drilled.

The recess 9 in the pot 2 for the spiral insert 7 is drilled in the machining process. The - slightly conical - diffuser opening 16 is also drilled. Also, the bore 15 for receiving the pinion shaft 19 is drilled. The screwing surface 17 for screwing the pressure nozzle tube 5 on the pot 2 is milled.

The spiral insert 7 is like FIG. 1 shows so fitted in the pot 2 that the axial end face of the spiral insert 7 an enclosed space which forms the annular space 23 remains. 2 and FIG. 3 show a side view ( FIG. 2 ) as well as a plan view ( FIG. 3 ) of or on the pot 2 according to the invention, produced by machining in a machining operation from a blank 3.

In the representations of the pot 2 in 2 and FIG. 3 are sections IV-IV ( FIG. 3 ), VV ( FIG. 2 ), VI-VI ( FIG. 3 ) and VII-VII ( FIG. 2 ), whose sectional views in the FIG. 4 . 5, FIG. 6 and FIG. 7 are shown.

As shown in FIGS. 2 to 7, the pot 2 has - in the radial cross-section - a teardrop-shaped outer contour, which extends in the axial direction for the spatial formation of the pot 2. The teardrop-shaped outer contour is formed by a% circle followed by a rectangle.

At one axial end of the pot 2, the recess 9 is inserted for receiving the spiral insert 7, whereby the pot 2 acquires its pot-shaped configuration; at the other axial end, the bore 15 for receiving the pinion shaft 19 is inserted into the pot 2.

In the area of one of the two rectangular sides of the rectangle on the outer contour of the pot 2, the screwing surface 17 for plant piping 4 and the pressure nozzle tube 5 incorporated. The screwing surface 17 is substantially rectangular, with a corner of the rectangle is rounded.

In the central region of the screwing surface 17 there is a radial, largely conical bore, which opens into the recess 9 in the pot 2 and forms the diffuser opening 16.

Concentrically around the diffuser opening 16, threaded bores 27 for screws 21 for the screw connection from the pressure nozzle tube 5 to the pot 2 are introduced into the screwing surface 17.

FIG. 8 shows a schematic representation of a blank 3 for the pot 2 according to the invention for the weld free pot spiral housing 1 in block design.

This in FIG. 8 shown blank 3 has in its outer contour a - like the pot 2 - drop-shaped shape or shape, which results in a% circle with subsequent square.

This teardrop-shaped blank 3 is made by forging a body 14 to a cylindrical base body 13 in the die.

In the machining of the blank 3 to the finished pot 2, the outer contour of the blank 3 is turned off to a small extent (see Abtrag 26) to remove bumps on the blank 3.

The Verschraubungsfläche 17 for plant piping 4 and the discharge nozzle tube 5 is on the blank 3 GE or milled and optionally reworked by smoothing; Tapped holes 27 for the screws 21 of the screw connection of pressure pipe 5 and pot 2 are introduced into the screwing surface 17.

The cylindrical bore 9 and the recess 9 for receiving the spiral insert 7 in the tube 2 is drilled; the borehole walls of the recess 9 are optionally turned or smoothed.

The bore 15 for receiving the pinion shaft 19 is also drilled; the borehole wall of the bore 15 is optionally turned or smoothed.

The diffuser opening 16 for the outflow of the fluid 11 from the pot 2 into the discharge pipe 5 is also drilled; the borehole walls of the diffuser opening 16 are optionally turned or smoothed.

Figures 9 to 11 show embodiments of the blank, which are not part of the present invention.

FIG. 9 and FIG. 10 show more different schematic representations of a blank 3 for a pot 2 for the weld free pot spiral housing 1 in block design.

This in FIG. 9 illustrated blank 3 for the pot 2 is a cuboid, forged solid material body or block with approximately rectangular cross-section.

This in FIG. 10 shown blank 3 for the pot 2 is a cylindrical solid material body. This can be forged or off the shelf.

FIG. 11 shows a perspective view of the cylindrical blank 3 after FIG. 10 with - indicated - finished "fitted" finished pot 2.

Again, ie in the cuboid or cylindrical blank 3 is - as in the teardrop-shaped blank 3 - the blank outer contour turned off in the machining to the finished pot 2. The cylindrical bore 9 or the recess 9, the bore 15 for receiving the pinion shaft 19 and the diffuser opening 16 are also drilled and reworked; the screwing 17 is gilled or milled and post-processed.

As a comparison of the different blanks 3 (drop-shaped, cuboid, cylindrical) in FIGS. 8, 9 and 10 shows, the amount of material 26 removed during the machining of the blank 3 is limited to the drop-shaped blank 3 (FIG. FIG. 8 ), whereas the material 26 removed during the machining of the blank 3 is at its lowest in the cylindrical blank 3 (FIG. FIG. 10 ) is the largest. Accordingly, the blank weight of the cylindrical blank 3 is the largest, whereas it is the smallest in the teardrop-shaped blank 3.

Although the invention has been further illustrated and described in detail by the preferred embodiments, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention as defined by the following claims ,

Claims (7)

1. Method for producing a pot (2) for a pot-type volute casing (1) for a compressor (10),
   wherein
   the pot (2) is produced from a blank by way of a cutting manufacturing process,
   characterized in that
   the blank (3) has a substantially droplet-shaped external contour as viewed in cross section.
2. Method according to Claim 1,
   characterized in that
   the cutting manufacturing process is a turning, milling and/or drilling process.
3. Method according to at least the preceding claim,
   characterized in that
   the blank (3) which is substantially droplet-shaped in cross section is produced by forging of a body on a substantially cylindrical main body in a die.
4. Pot-type volute casing (1) of a geared turbocompressor (10), characterized in that the pot-type volute casing (1) has a pot (2) with a droplet-shaped external contour, which pot is produced according to at least one of the preceding method claims.
5. Pot-type volute casing (1) according to Claim 4,
   characterized by a plant pipework (4) which is screwed to the pot (2), in particular a pressure connector pipe (5) which is screwed to the pot (2).
6. Pot-type volute casing (1) according to at least one of the preceding arrangement claims,
   characterized by a machined external contour surface on the pot (2), by way of which external contour surface a plant pipework (4), in particular a pressure connector pipe (5), can be screwed to the pot (2).
7. Geared turbocompressor (10) having a pot-type volute casing (1) according to at least one of the preceding arrangement claims and having a gearbox connection (8) screwed to the pot (2) of the pot-type volute casing (1), in particular a collar (8) screwed to the pot (2) of the pot-type volute casing (1).

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