JPS6135394B2 - - Google Patents

Description

Detailed Description of the Invention The present invention involves attaching wings to either the main plate or the side plates, and drilling slits through the other plate in accordance with the shape of the wing at the locations where the wings are attached. and expose the end face of the wing to the slit.
The present invention relates to a method for manufacturing a compressor impeller in which a plate and a blade are welded and integrated at the slit.

As the discharge pressure of a turbo compressor increases,
The gap between the main plate and the side plate, that is, the blade span of the gas passage, has become smaller, and in some recent ultra-high pressure compressors this is 2 to 3 m/m. In an impeller with such a small blade span, it is difficult to finish the gas passage after the main plate and side plates are assembled, so a manufacturing method that does not require such finishing is required. Such a conventional manufacturing method is shown in FIGS. 1 and 2. Figures 1a and 2 are cross sections including the impeller shaft;
FIG. 1b is a view taken along the line AA in FIG. 1a. Figure 2 shows the finished shape, with 1' being the main plate, 2' the side plates, and 3' the wings. According to the conventional manufacturing method, first the side plate 2'
The wings 3' are attached to the side plate material 12', which is the material of
A slit 1a having the same shape as the wing 3' but slightly narrower in width is cut in the main plate material 11' which is the material of the main plate 1' at the mounting position of the wing 3'. Then, as shown in Fig. 1a, the side plate 12' and the main plate 11' are attached to the wing 3'.
The main plate 11' and the wing 3' are stacked so that the end faces of the blades are exposed between the slits, and the main plate 11' and the wing 3' are
After welding them together, they are finished to the specified dimensions. The problems with this construction method are the distortion that occurs in the main plate 1' and the side plate 2' during welding, and the shrinkage of the blade span W. For example, as shown in Fig. 3 when viewed from arrow A-A in Fig. 1a of the impeller, deformations such as waving [a in the same figure] and contraction of the blade span from W to W' [b in the same figure] occur. 〓〓〓〓
Ru. In ultra-high pressure compressors with a blade span of 2 to 3 m/m, these deformations greatly affect air volume, efficiency, etc. In addition, as previously mentioned, as shown in Figure 1b, the slit width T'' was smaller than the blade thickness T, so the weld between the main plate 11' and the blade 3' could not be completely welded, leaving a notch. To avoid this, special machining such as electrical discharge machining and electrolytic machining is used, but the present invention solves this problem by improving conventional machining methods without using these special machining methods. This is what I did.

That is, according to the impeller manufacturing method of the present invention,
The main plate material and side plate material, which are the materials of the main plate and side plates that make up the impeller, have an outer diameter part and an inner diameter part in the radial direction.
Extra thickness is provided on the outer side of the impeller in the width direction and in the axial direction on the inner diameter. In addition, both plates fit into each other at a part larger than the outer diameter of the impeller and at the inner diameter part while leaving the height of the blades, and the outer diameter part and the inner diameter part have a contact surface perpendicular to the axis. The width of the slit in the plate material on which the wings are not attached should be slightly larger than the thickness of the wing. Both plate materials processed in this way are aligned with the blade end surface and the slit, and the two plate materials are fitted together and temporarily attached. After welding the slit portion and the blade tip surface, heat treatment is performed, and the excess material is shaved off. I decided to drop it and finish it to the specified dimensions.

Next, the manufacturing method according to the present invention will be explained with reference to the drawings in the case where wings are attached to the main plate. Fig. 4 shows the process according to the present invention, in which Fig. 4A shows the main plate, Fig. 4B shows the side plate, Fig. 4C shows the main plate and side plate fitted together, and Fig. 4D shows the finished state. The cross section including the impeller shaft, FIG. 5, is taken along the line BB in FIG. 4c. In Fig. 4d, 1 is the main plate, 2 is the side plate, and 3 is the wing. D ₀ is the outer diameter of the impeller, d ₀ is the inner diameter, h ₀ is the height in the width direction, W is the blade span, and B ₀ is the width at the outer diameter of the impeller. In the same figure a, 11 is the main plate material of the main plate 1, its outer diameter D ₁ is larger than the outer diameter D ₀ of the impeller, and its inner diameter
d ₁ is made smaller than the inner diameter d ₀ of the impeller to provide extra thickness in those parts. Also, the width of the outer diameter of the impeller
Extra thickness is provided in the portion B ₁ corresponding to B ₀ and also in the height h ₁ relative to the axial height h ₀ of the impeller. The wings have been installed and are almost finished. In the same figure b, the outer diameter D ₁ of the material of the side plate 12 of the side plate 2 is larger than the outer diameter D ₀ of the impeller, and its inner diameter d ₁ is the inner diameter d ₀ of the impeller.
It is smaller and has extra meat in this part. There is also extra thickness in the _B2 part, which is the outside of the impeller, and the _H2 part, which is the height in the axial direction. The inner surface, which will become the gas passage, has been finished. Main plate material 11 and side plate material 12
and the fitting parts d and c for centering when the two plates are overlapped as shown in the same figure c, and the outer diameter of the impeller.
A diameter D ₂ that is larger than D ₀ and a diameter D ₂₀ that is smaller than the inner diameter d ₀ of the impeller are provided in each of the two materials as described later so that the blades can fit together while ensuring the blade span W. In addition, to ensure the wing span during welding, the main plate material 11 and the side plate material 12
The mutual contact surfaces B and A on the plane perpendicular to the axis of are the outer diameter parts.
D ₂ is made at the inner diameter part d ₂ . Next, make a slit 2a in the side plate material 12 slightly larger than the blade thickness T.
Cut to the desired shape at T′, that is, to match the shape of the blade tip surface. As a result, a ring-shaped part having an outer diameter D ₁ , an inner diameter D ₂ , and a width B 2 is formed at the fitting part ₂ of the outer diameter part of the side plate 12, and this ring-shaped part has a blade width W.
It becomes a reinforcing part that holds the In other words, since the slits 2a are formed in the side plate material 12, it cannot be made as thick as the main plate material 11, so that distortion is likely to occur at the welded portion, and this ring-shaped portion serves to prevent this distortion. After the manufacturing steps shown in Figures 4a and 4b are completed, as shown in Figure 4c, the main plate 11 and the side plates 12 are fitted together at the fitting parts C and D, and the contact surfaces A and B are fitted together.
Insert until you hit the spot. The blade thickness T of the end surface of the blade 3 and the slit width T' are aligned. Both materials 11,1
Outer diameter part D ₁ which is the seam of 2 and E of 1, and inner diameter part
Temporarily attach the two pieces to _d1 . In this state, slit 2
The blade 3 and the side plate material 12 are integrated by filling the space a by welding. Next, the stress is removed by this heat treatment, and the excess thickness is scraped off to finish the product into the predetermined shape shown in FIG. 4d.

In the above process, if the blade is machined, it is easier to place it on the main plate side, and if it is welded, it is easier to place it on the side plate side. This is because there is no sloped part on the inner surface of the main plate. In addition, by providing sufficient extra thickness on the outer diameter part, inner diameter part, and back surface of the impeller, and by making sure to fit in parts C and D as part of the processing process, and to make contact surfaces in A and B on the plane perpendicular to the axis,
We decided to prevent the distortion that occurs during welding.

[Brief explanation of the drawing]

Figures 1a and 2 are examples of conventional manufacturing methods, and a cross section including the impeller shaft, and Figure 1b is A-A in Figure 1a.
It's an arrow view. Figure 3a shows the strain caused by conventional welding, and Figure 3b shows the reduction in the blade span. Figure 4 shows the manufacturing process of the present invention, with figure a showing the main plate and figure b showing the side plate.
The plates are shown in cross-section including the shaft of the impeller, with Figure C showing the main plate and side plate fitted together, and Figure D showing the finished state. 1, 1'...Main plate, W...Blade span, 2, 2'...Side plate, T
...blade thickness, 3,3'...blade, T',T''...slit width,
1a, 2a...slit, 11, 11'...main plate material,
12, 12'...Side plate material. 〓〓〓〓〓

Claims (1)

[Claims] 1 Attach the wing to either the main plate or the side plate, make a slit through the other plate to match the shape of the wing at the point where the wing will be attached, and fit these two plates together to make the end surface of the wing as described above. In a compressor impeller construction method in which the plates and blades are welded together through the slits, the main plate and side plates are radially aligned at the outer and inner diameter portions, and outward from the impeller in the width direction. By leaving extra thickness in the axial direction at the inner diameter part and at the inner diameter part, and leaving the height of the blades at the part larger than the outer diameter of the impeller and at the inner diameter part, there is a fit where both plates fit, and a part perpendicular to the axis. Make a contact surface with a flat surface, make the width of the slit slightly larger than the thickness of the blade, and temporarily attach the two plates that have been processed in this way by fitting them together, aligning the end face of the blade with the position of the slit. This method of manufacturing an impeller involves welding the plate and blade end surface together and then scraping off the excess material.