Method for producing a cylindrical component

Abstract

The invention relates to a method for producing a cylindrical component, particularly of turbomachines. In the process, a heated blank is provided. The blank is then formed to create a flat blank (2). The flat blank (2) is next bent and/or rolled to form a cylindrical half-shell (40).

Claims

1. A method for producing a cylindrical component for turbomachines, comprising the steps of: (a) providing a heated blank; (b) press forming the heated blank to form a flat blank; (c) bending or rolling the flat blank into a cylindrical half-shell; (d) forming at least two half-cylindrical-shells with steps (a) through (c); and (e) configuring and arranging the at least two half-cylindrical-shells formed in step (d) into a housing.

2. The method according to claim 1, wherein the flat blank is substantially rectangular in shape.

3. The method according to claim 1, wherein the flat blank has a machining allowance on at least one of its contours.

4. The method according to claim 3, wherein the machining allowance is between 0 and 10 mm.

5. The method according to claim 1, wherein at least one rib and/or one eyelet is formed in at least one surface of the blank.

6. The method according to claim 1, wherein at least one contact surface of each of the half-cylindrical-shells is machined to a final dimension.

7. The method according to claim 1, wherein the step of press forming is accomplished by drop forging.

8. The method according to claim 1, wherein the at least two half-cylindrical-shells have identical outer contours after the step of press forming is complete.

9. The method according to claim 8, further comprising the step of: (f) providing the housing as a cylindrical component in a turbomachine.

10. The method according to claim 8, further comprising the step of: providing the housing as a cylindrical component in a turbomachine.

11. A method for producing a cylindrical component for turbomachines, comprising the steps of: providing a heated blank; press forming the heated blank to form a flat blank; bending or rolling the flat blank into a half-cylindrical-shell; forming at least two half-cylindrcal-shells; and configuring and arranging the at least two half-cylindrical-shells into a housing, the at least two cylindrical half-shells having identical outer contours after the step of press forming is complete.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) In the following, preferred exemplary embodiments of the invention will be described in detail on the basis of the schematic drawing. Shown therein are:

(2) FIG. 1 is a plan view of a blank according to the invention, and

(3) FIG. 2 is an oblique view of a half-shell according to the invention.

DESCRIPTION OF THE INVENTION

(4) Shown in FIG. 1 is a plan view of an essentially rectangularly shaped blank 2 according to the invention. Preferably, the flat blank 2 is drop-forged beforehand using a closed forging die. The blank 2 has a top lengthwise edge 4 and a bottom lengthwise edge 6, which are joined at their ends via a first cross edge 8 depicted on the left in FIG. 1 and a second cross edge 10 depicted on the right in FIG. 1. The outer face 12 can be seen between the edges 4 to 10. A first flange projection 14 is formed on the outer face 12 along the top lengthwise edge 4 and has the maximum thickness d.sub.m of the blank 2. Furthermore, a second flange projection 16 is formed on the outer face 12 along the bottom lengthwise edge 6 and likewise can have the maximum thickness d.sub.m of the blank 2. The blank 2 is designed to be somewhat thinner between the two flange projections 14 and 16 and exhibits a thickness d.sub.R that is less than the maximum thickness d.sub.m.

(5) The front first contact surface 13 borders the bottom lengthwise edge 6 on the outer face 12. The rear second contact surface 15, which is not depicted, borders the top lengthwise edge 4 on the outer face 12. The third contact surface 17 borders the first cross edge 8 on the outer face 12. The fourth contact surface 19, which is not depicted, borders the second cross edge 10 on the outer face 12.

(6) A plurality of cross ribs 18 to 30 lie between the flange projections 14 and 16 and, in this case, are parallel to the cross edges 8 and 10. The position of the ribs is typically defined by the strength requirements. In this case, all cross ribs 18 to 30 have the same thickness d.sub.R. Molded between the cross ribs 22 and 24 are two upset eyelets 32 and 34, which can be bored out in a latter processing step. It is also conceivable that, instead of the upset eyelets 32 and 34, eyelets can be produced directly by press forming. This would save a later machining step (for example, boring) that produces material debris.

(7) The cross ribs 26 to 30 can be joined to one another via a lengthwise rib 36, if this is required for reasons of structural mechanics, for example.

(8) The outer face 12, together with all corresponding contours, such as ribs and/or upset eyelets or eyelets, may be produced advantageously without any machining allowance during drop forging, so that any later machining of this outer face 12 is dispensed with.

(9) The blank 2 is than bent or rolled, so that the essentially cylindrical half-shell 40 depicted in FIG. 2 is created. In this process, particularly the lengthwise edges 4 and 6 are bent, so that the first and second contact surfaces 13 and 15 describe a semicircle, with the outer face 12 constituting the jacket surface of the half-cylinder. Once bending is complete, the individual contact surfaces 13, 15, 17, and 19 may be additionally finished, preferably by machining them, so as to obtain the required dimensional accuracy. Thus, a particularly high planarity of the contact surfaces 17 and 19 is required if two such half-shells are to be assembled to form a housing. As a result, it is then ensured that the required tightness is achieved between two half-shells 40 at the contact surfaces 17 and 19. Various indentations 44 may be present on the inner face 42 of the half-shell 40.