JPH05901U - Radial turbine casing - Google Patents

Abstract

(57) [Abstract] [Purpose] Even when the scroll casing of the radial turbine is small or the scroll outlet (4) is narrow, it prevents the core from welding at the scroll outlet during casting, and also causes the inner surface to form. Make it easy to correct unevenness. In the scroll passage cross section (2), the side wall angle (10) of the side wall surface (3) on the turbine outlet side is constant and is an axis target.
It is divided by a cylindrical surface coaxial with the turbine axis and separable in the axial direction, and is tightened and integrated with a tightening bolt (11) or the like.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a scroll type casing of a radial turbine.

[0002]

[Prior Art]

 FIG. 2 is a vertical sectional view showing an example of a conventional radial turbine scroll. The working fluid flowing in the direction of the arrow from below in the figure is given a radial velocity to the moving blade (05) by the flow passage scroll (01) provided in a spiral shape around the moving blade (05). To do. The rotor blade (05) is given work to rotate by the circumferential velocity of the flow that has flowed in from the scroll outlet (04).

Generally, in a scroll (01), a passage cross-sectional area (02) changes linearly, and further, a scroll passage average radius (08) or a passage outer wall diameter (09) changes smoothly according to a logarithmic spiral line or the like. To design. However, the cross-sectional shape of the passage is various, and it is cast as an integral casting, and the joint is machined into a product.

[0004]

[Problems to be solved by the device]

 In the conventional radial turbine casing, when the scroll (01) is small or the scroll outlet (04) is narrow, the core may be welded at the scroll outlet (04) during scroll casting production. .. In addition, there is also a drawback that it cannot be corrected when irregularities occur on the scroll passage surface.

[0005]

[Means for Solving the Problems]

 In order to solve the above conventional problems, the present invention provides a scroll of a radial turbine in which the turbine outlet side wall surface of the scroll passage cross section of the scroll body is a side wall surface having a constant side wall angle, and the side wall surface is in the middle. The casing of the radial turbine is characterized in that a scroll side wall member having an axially symmetric shape that is divided from the main body by a cylindrical surface concentric with the rotor shaft center and is axially separable is bolted to the scroll main body. Is proposed.

[0006]

[Action]

 In the present invention, by dividing the scroll passage cross section into two, it is possible to increase the gap between the metals during casting, and to prevent core welding. Also, it becomes easy to correct irregularities in the scroll passage.

[0007]

【Example】

 FIG. 1 is a vertical sectional view showing an embodiment of the present invention. In this figure, the parts similar to the conventional one described with reference to FIG. 2 are given the same reference numerals as those used in FIG. Omit detailed explanation.

In the present embodiment, the cross section (2) of the scroll passage is such that the side wall angle (10) of the turbine outlet side side wall surface (3) is constant and axisymmetric, and the rotor shaft is in the middle of the constant side wall surface. It is divided into a scroll body (1A) and a scroll side wall member (1B) by a cylindrical surface coaxial with the core, and these can be separated in the axial direction, and they are tightened with a tightening bolt (11) or the like to be integrated. The scroll side wall member (1B) is integral with the shroud surface (6).

[0009]

[Effect of the device]

 According to the present invention, in the cross section of the scroll passage, the side wall angle is constant and axisymmetric, and the side wall surface having a constant angle is divided, so that the scroll body can prevent core welding during casting. Further, the unevenness in the scroll passage can be easily corrected. Furthermore, since the scroll side wall member is entirely axisymmetric (that is, a rotating body), it can be manufactured by machining instead of casting, and when scrolls with different scroll outlet dimensions are manufactured. However, since it is not necessary to manufacture each by casting, the cost can be reduced. Further, as described above, the passage surface can be easily corrected, so that the performance can be improved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a turbine scroll according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing an example of a conventional turbine scroll.

[Explanation of symbols]

 (01) Scroll (1A) Scroll body (1B) Scroll side wall member (02), (2) Scroll passage cross section (03), (3) Pass side wall (04), (4) Scroll outlet part (05), (5 ) Blades (06), (6) Shroud surface (07), (7) Turbine outlet (08), (8) Scroll passage average diameter (09), (9) Scroll passage outer wall diameter (10) Side wall angle (11) ) Tightening bolt

Claims (1)

Claims for utility model registration 1. In a scroll of a radial turbine, the turbine outlet side wall surface of the scroll passage cross section of the scroll body is a side wall surface having a constant side wall angle, and in the middle of the side wall surface. A casing for a radial turbine, characterized in that a scroll side wall member having an axisymmetric shape that is divided from the main body by a cylindrical surface concentric with the rotor shaft center and is separable in the axial direction is fastened to the scroll main body with bolts.