Abstract
A method for manufacturing a housing of a turbomachine, in particular a housing of a radial turbo compressor. The method includes the following steps: a) providing a hollow body that is closed in a circumferential direction and extends along an axis; b) coating the inner side of the hollow body with a corrosion-resistant layer that is more resistant to corrosion than the material of the hollow body; c) dividing the hollow body into two half-shells along the axis in a separation joint plane; d) assembling the housing by joining both half-shells and fastening both half-shells in the region of the separation joints, which were created by separation, by means of detachable fastening elements.
Claims
1. A method for manufacturing a housing of a turbomachine, in particular a housing of a radial turbo compressor, comprising the following steps: a) providing a hollow body which is closed in a peripheral direction and extends along an axis; b) coating the inside of the hollow body with a corrosion-resistant layer which is more corrosion-resistant than the material of the hollow body; c) separating the hollow body into two half-shells along the axis in a separating joint plane; d) assembling the housing by joining the two half-shells and fixing the two half-shells in the region of the separating joints which were created by separation, by means of releasable fixing elements.
2. The method as claimed in claim 1, wherein by means of mechanical machining, in particular material-removal machining, the two half-shells are prepared before and/or after separation in the manner of a flange in the region of the separating plane, so as to prepare for the fixing of the two half-shells to each other by means of the fixing elements in step d).
3. The method as claimed in claim 1, wherein the hollow body is configured as a hollow cylinder.
4. The method as claimed in claim 1, wherein the hollow body is configured so as to be rotationally symmetrical.
5. The method as claimed in claim 1, wherein the coating is applied by deposition welding.
6. The method as claimed in claim 5, wherein the deposition welding is performed automatically.
7. The method as claimed in claim 5, wherein the hollow body is subjected to stress-relief annealing after the deposition welding (step d) and before the separation (step c).
8. The method as claimed in claim 1, wherein the hollow body is separated into two half-shells by means of another material-removal process, in particular by means of a saw cut, by means of erosion, by means of burning, by means of waterjet cutting, by means of laser beam cutting or by means of electron beam cutting.
9. The method as claimed in claim 1, wherein the volume lost by the separation of the hollow body in the region of the separating joint plane is compensated by corresponding surplus of the deposition welding in the interior of the hollow body and subsequent mechanical machining of the diameter of the hollow body formed by the two half-shells after separation.
10. The method as claimed in claim 1, wherein a volume lost by separation of the hollow body in the region of the separating joint plane is compensated by means of deposition welding on at least one of the two mutually opposing cut edges of the half-shells which form the separating joint.
11. The method as claimed in claim 1, wherein after separation of the hollow body, radial openings are provided in the walls of the half-shells for connection of pipelines.
12. The method as claimed in claim 5, wherein a stainless steel or a nickel-based alloy is used for the deposition welding.
13. (canceled)
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The drawings show:
[0015] FIG. 1 a diagrammatic cross-section through a prepared hollow body of a housing according to the invention without corrosion protection;
[0016] FIG. 2 the hollow body of the housing according to the invention as shown in FIG. 1 after a separating cut in the separating joint plane, with a connecting piece of non-corrosion-resistant material with a corrosion-resistant layer LY;
[0017] FIG. 3 the depiction in FIG. 2 only with a connecting piece of corrosion-resistant material;
[0018] FIG. 4 the diagrammatic depiction of two half-shells attached to each other, wherein the upper half-shell is prepared for a connecting piece;
[0019] FIG. 5 a diagrammatic depiction of a variant of the hollow body configured with rectangular cross-section;
[0020] FIG. 6 a diagrammatic depiction of the cross-section of FIG. 5 after preparation of the housing for the purpose of bolting the two half-shells together;
[0021] FIG. 7 a diagrammatic depiction of the configuration of FIG. 6 in a top view from radially above;
[0022] FIG. 8 a diagrammatic depiction of the process sequence.
DETAILED DESCRIPTION OF INVENTION
[0023] The depictions of the figures are all diagrammatic and greatly simplified. FIGS. 1 to 6 each show an axial view of a cross-section of a hollow body CY or two half-shells HCY along an axis X. FIG. 7 shows a radial top view in diagrammatic form onto a housing C as shown in cross-section in FIG. 6. The position of the cross-section of FIG. 6 is indicated in FIG. 7 as VI.
[0024] The hollow body CY shown in cross-section in FIG. 1 is already prepared for the application of fixing elements FE by means of milling in the upper part UH. The fixing elements FE are advantageously formed as bolts. The position of the fixing elements FE for later assembly is indicated diagrammatically by dotted lines. After a subsequent step of coating the base material of the hollow body with a more corrosion-resistant material, the hollow body CY is separated into an upper half UH or half-shell CY and a lower half LH or half-shell HCY in a separating joint plane SSP, giving a separating joint SP. The fixing elements FE then, as indicated diagrammatically by means of the dotted lines, extend through the upper half UH along a bored hole BH and are screwed into a threaded bore TBH of the lower half LH, so that the support shoulders SH formed on the upper half UH are suitable as counter-bearings for clamping against the lower half LH by means of the fixing elements FE in threaded bores TBH.
[0025] FIG. 2 shows a variant of the housing C according to FIG. 1 after further process steps. The separation, indicated by means of the hatching in FIG. 1 which is different for each of the two half-shells HCY, is already completed in FIG. 2, after a coating of the more corrosion-resistant material has been applied as a layer LY on the inside of the hollow body CY. In this concrete exemplary embodiment, said application took place using deposition welding before separation, wherein after deposition welding, stress-relief annealing was carried out so that the hollow body CY could be separated into two half-shells HCY largely without distortion. Following the separation of the hollow body CY, a radial opening OP was made in the upper half UH and a connecting piece TR welded on in the region of the opening OP by means of a weld seam WD. On the inside of the surface provided for flow guidance, the connecting piece TR is also coated with the more corrosion-resistant material in the form of a layer LY, wherein the connecting piece TR has a flange face which is at least partially also provided with a layer LY, so that a corrosive process medium present in the flange plane during operation of the radial turbo compressor cannot damage these flange surfaces.
[0026] As an alternative, the entire connecting piece TR shown in FIG. 3 is made of the more corrosion-resistant material and attached to the upper half UH of the hollow body CY in the region of the opening OP by means of a weld seam WD.
[0027] FIG. 4 shows a further alternative for the connecting piece TR. The connecting piece TR is here bolted in the manner of a flange directly to the upper half UH by means of fixing elements FE which are indicated by dotted lines. In preparation for this connection to the connecting piece TR, the upper half UH is machined flat in the region of the opening OP and provided with a layer LY of a more corrosion-resistant material.
[0028] FIG. 5 shows the diagrammatic cross-section through a cuboid blank QD or a blank which has a rectangular cross-section. This corresponds to the hollow body CY already known from the other exemplary embodiments, wherein the cavityhere shown as round in cross-sectionis arranged with its cross-section center CCY eccentric to the cross-section center CQD of the blank QD. The eccentricity refers to the parallel shift of the two axes of the cavity and the blank. The cross-section centers applied correspond substantially to the longitudinal extension of the two geometries, as can be seen from FIG. 7 with reference to axis X. The eccentric offset of the cavity in the blank QD allows production of inlet connecting piece IN and outlet connecting piece EX, as shown in FIGS. 6 and 7. In the region of the connecting pieces, the blank QD offers more material so as to provide sufficient flexibility in the design of the connecting pieces EX, IN. Before separation of the blank QD or the hollow body CY, the interior is coated with the more corrosion-resistant layer LY, as shown in FIG. 6. In some cases, also before separation, the inner surfaces of the connecting pieces IN, EX may be coated with the layer LY. The blank QD or the hollow body CY is separated in the separating joint plane SSP. Shoulders SH are machined into the blank QD so as to serve as counter-bearings for the fixing elements FE which fix the two half-shells HCY to each other in a manner not depicted in detail.
[0029] FIG. 8 shows a flow diagram of a method which has the features according to the invention, for manufacturing a housing of the radial turbo compressor, with the following steps: a) providing a hollow body extending along an axis; b) deposition welding on the inside of the hollow cylinder (ZY) with a corrosion-resistant layer which is more corrosion-resistant than the material of the hollow cylinder; b1) stress-relief annealing of the hollow cylinder; c) separating the hollow cylinder into two half-cylinders along the axis; d) assembling the housing by joining the two half-cylinders and fixing the two half-cylinders in the region of the separating joints which were created by separation, by means of releasable fixing elements.
