RU2586553C1 - Method of making compressor or fan impeller from composite material - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to turbo machines building, namely to production of compressor or fan impellers from composite materials. Method of making compressor impeller from composite material containing working blades, thrust ring, front and rear flanges, which includes cutting of composite material layers for formation of workpiece intended for bearing ring front and rear flanges and part of support ring with aerodynamic profile. Cutting of composite material layers for blades to ensure output beyond blade circuit on side of root cross section on length exceeding length of bearing ring arc between adjacent blades, part of material to be used to form part of support ring. Pressing blades to produce support ring blank on side of root section with preservation of part extending beyond blade material to be used to form part of support ring, in initial state. Laying of billet in mold intended for formation of front and rear flanges and part of support ring, with arrangement of parts of billet into mold separator cavity intended for formation of front flange and aerodynamic profile of support ring. Subsequent laying of blades in slots of separator. Impregnation and laying layers of material extending beyond blades with preforming of support ring. Installation of elastic puncheon in mold, on which material layers for rear flange are laid. Installation of pressure male die, its attachment to separator and formation of monolithic impeller with pressing by feeding pressure at elastic male die. At that, between layers of material for rear flange ring composite material blanks are laid, which number is determined by calculation of strength.

EFFECT: high strength of rear flange to level of strength of front one.

1 cl, 10 dwg

Description

The invention relates to the field of turbine engineering, and more specifically to methods of manufacturing impellers from composite material for a compressor or engine fan, mainly aviation.

Known impeller (RU No. 2382910, class F04D 29/26, published February 27, 2010), the design of which contains individual sectors of a layered composite material on a polymer basis, combined into an impeller by at least four load-bearing force rings of composite material, and each sector includes one working blade, the tail of which is made in the form of a shank leg with curvilinear geometry defined by shelves separated by grooves placed along the height of the legs, under the corresponding power rings, placed e in these grooves. According to this invention, obtaining a monolithic wheel is achieved, however, a massive hub increases the relative mass of the wheel, a complicated technology for manufacturing the shank of the blade, and the fibers of the composite material are cut, which reduces the strength of the wheel,

A known method of obtaining the impeller of the compressor (patent RU No. 2502601, B29D 15/00, publ. 12/27/2013) from composite materials. The method includes a number of operations in a certain sequence. Layers of composite material are cut to produce blanks from which the front and rear flanges and part of the support ring with an aerodynamic profile are formed. The layers of the composite material for the blades are also cut, which is carried out to ensure that the outside of the contour of the blades from the side of the root section exceeds the length of the arc of the support ring between adjacent blades, a part of the material intended to form part of the support ring. The blades are pressed to obtain an outline of the support ring from the root section. Workpieces intended for forming the front and rear flanges and part of the support ring are placed in the mold. At the same time, part of these blanks is placed in the cavity of the mold separator. Then, blades are placed in the slots of the separator to ensure the nominal location of the blades on the support ring. The layers of material extending beyond the contour of the blades are impregnated and laid, with the preliminary formation of the support ring. An elastic punch is installed in the mold, which ensures the formation of the inner surfaces of the support ring, the front and rear flanges. Layers of material for the rear flange are placed on the punch. Then, the compression mold punch is installed, which is fastened to the separator. By applying pressure to an elastic punch, the compressor is pressed and formed into a monolithic impeller. The resulting impeller has a lightweight design and increased strength characteristics.

However, with this impeller, the rear flange is less durable than the front flange. This is because the front and rear flanges are formed from a single blank of composite material, while the front flange is obtained from the annular part, and the rear flange from individual sectors equal to the number of blades in the impeller. After laying the sectors of the composite material on an elastic punch and pressing to the finished product, the flanges are obtained, as described above, with different strength characteristics, which is extremely undesirable for the impellers of an aircraft engine.

The problem solved by this invention is to ensure equal strength of the front and rear flanges.

The problem is solved in that when assembling the mold between the layers of the sectors forming the rear flange, stack annular blanks of composite material. The number of ring blanks is determined by the strength of the rear flange.

The present invention is illustrated by the following figures:

FIG. 1 - General view of the impeller,

FIG. 2 - cutting a layer of composite material of the scapula,

FIG. 3 - cutting a layer of composite material for the formation of a support ring, front and rear flanges,

FIG. 4 - annular blank of composite material,

FIG. 5 is a diagram of the pressing of the blades,

FIG. 6 - the blade after pressing,

FIG. 7 - the mold after laying in the blades of the composite material for the design of the flanges and the support ring,

FIG. 8 - section aa of the mold,

FIG. 9 - mold, ready for pressing,

FIG. 10 - section BB of the rear flange.

The impeller (Fig. 1) includes the blades 1 (the aerodynamic profile of the blades is not shown conventionally), the support ring 2, the front flange 3 and the rear flange 4. The support ring 2 is formed from composite material 5 extending beyond the contour of the blade 1 during cutting (Fig. .2) material 6, which is formed from the workpiece (Fig. 3) and which forms the aerodynamic profile of the support ring. From the same blanks, front 3 and rear 4 flanges are formed (Fig. 1 and Fig. 3).

This design takes into account that composite materials have the greatest tensile strength along the fibers, and the most loaded due to the action of centrifugal forces is the place of attachment of the blades to the support ring, therefore, the fibers in part 5 under the action of these forces will delaminate to eliminate this defect support the ring is reinforced with flanges, which are united by part 6 of the support ring and are made of a single cut material. Thus, the front 3, rear 4 flanges and part of the support ring 6 form a power element of the impeller, in which the fibers work in tension, because flanges are a fastener through which the forces arising from the rotation of the wheel are transmitted. The channel-shaped cross section of the power element (flanges 3, 4 and part of the support ring 6) provide high specific strength of the entire design of the impeller. In this design, the rear flange is inferior in strength to the front flange, this is due to the fact that the front flange is formed from the annular part 3 (Fig. 3), and the rear flange from individual sectors 4 (Fig. 3). In order to eliminate this drawback, it is necessary to improve the method of manufacturing the impeller.

A method of manufacturing a compressor impeller consists in cutting various sizes of material layers (Fig. 2) of the blades 1, while the layers are cut taking into account that the material 5 is intended to form part 5 of the support ring 2 (Fig. 1). Also, the layers of material are cut (Fig. 3) to design the front 3, rear 4 flanges and part of the support ring 6 (Fig. 1). To increase the strength of the rear flange prepare ring blanks 7 (Fig. 4). The number of layers and their sizes (Fig. 2, Fig. 3 and Fig. 4) are calculated for each specific wheel, taking into account the configuration of the blade, support ring, flanges and the required strength. Next, each layer that forms the feather of the scapula (Fig. 2) is impregnated with a binder in zones 1 and 8 (Fig. 2). Cutting zone 8 is designed to form part of the support ring 8 (Fig. 6) 1 ... 20 mm long, which fixes the blade in the separator 11 (Fig. 7, Fig. 8) in the radial direction. Then the layers are laid out in the mold matrix 9 (Fig. 5) of the mold, the punch 10 is installed and pressed in accordance with the technological regime for the composite material used. After disassembling the mold, a blade 1 is obtained (Fig. 5), a notch 8 is formed on its root section for part 5 of the support ring 2 (Fig. 1), part of the material 5 (Fig. 2, Fig. 5, Fig. 6) remains in the initial state, from which later part 5 of the support ring 2 will be formed (Fig. 1). Then they impregnate the cutting of the layers (Fig. 3) and lay them out in the mold, while the annular part 3 (Fig. 3) is placed in the separator 11 (Fig. 7) in the cavity 12, where the front flange 3 (Fig. 1 and Fig. 7), and the cutting part 6 is laid in the cavity 13 of the separator 11 (Fig. 3, Fig. 7 and Fig. 8), in which the part 6 of the support ring 2 is formed with the necessary aerodynamic profile (Fig. 1), when laying combine the slots 14 with the slots 15 of the separator 11 (Fig. 8). Then, in the slot 15 of the separator 11, the blades 1 (Fig. 7 and Fig. 8) are inserted until the basting 8 stops in the cutting part 6 and the material 5 is laid in the cavity 13 (Fig. 6, Fig. 7 and Fig. 8), after being impregnated with a binder . Part 5 of the support ring 2 (FIG. 1, FIG. 7, FIG. 8 and FIG. 9) will be formed from material 5 (FIG. 6, FIG. 7 and FIG. 8). Then, an elastic punch 16 is installed in the mold (FIG. 7, FIG. 8 and FIG. 9). Laying sectors 4 are laid on it (Fig. 3 and Fig. 9), but in each layer the joint of the sectors is a weak point in terms of strength. To create a rear flange, equal in strength to the front flange between the layers consisting of sectors 4, lay annular blanks 7 (Fig. 4, Fig. 9), the number of which is determined based on the strength of the flange. As an example (Fig. 10), an enlarged section B-B is presented, which shows the alternation of layers from sectors 4 and ring blanks 7. As is known, in a composite material, the reinforcing element - fabric is made from threads: warp and weft, therefore, the ring blank has different strengths when applying forces at different angles to the fabric base. To create an equal-strength flange when laying annular blanks into the mold, each of them is rotated relative to the previous one by an angle equal to 360: n, where n is the number of calculated annular blanks, while taking, for example, the basis of the fabric. Next, set the pressure punch 17 (Fig. 9), which provides the shape and dimensions of the rear flange, and fasten together with the separator, for example, bolts (not shown). The elastic punch 16 is supplied with pressure, for example, by the cone 18 (Fig. 7, Fig. 8 and Fig. 9), under the action of which the elastic punch 16 creates pressure on the composite material forming the support ring, the front and rear flanges. Pressing is carried out according to the regime corresponding to the applied composite material for the impeller.

After disassembling the mold, a monolithic impeller is obtained (Fig. 1), containing rotor blades, support ring, front and rear flanges.

This invention solves the problem of creating a highly loaded impeller design of a compressor or fan made of composite material with a significant reduction in specific gravity and increased stiffness and strength, while the front and rear flanges are equally strong.

Claims (2)

1. A method of manufacturing an impeller of a compressor or fan from a composite material containing rotor blades, a support ring, front and rear flanges, including cutting layers of composite material to obtain a workpiece designed to form the front and rear flanges and part of the support ring with an aerodynamic profile, cutting layers of composite material for the blades, which is carried out with the provision of going beyond the contour of the blades from the root section to a length exceeding the length the arcs of the support ring between adjacent blades, part of the material intended to form part of the support ring, pressing the blades to obtain from the side of the root section of the outline of the support ring while preserving the part of the material outside the blade contour intended to form part of the support ring in the initial state, laying in the mold of the workpiece designed to form the front and rear flanges and part of the support ring, with the location of the parts of the said workpiece in the cavity of the separator press molds designed to form the front flange and the aerodynamic profile of the support ring, the subsequent laying of the blades in the separator slot, providing the nominal location of the blades on the supporting ring, impregnation and laying of layers of material extending beyond the contour of the blades, with the preliminary formation of the supporting ring, installation in a press the shape of an elastic punch designed to form the inner surfaces of the front and rear flanges and the support ring, on which the layers of material I of the back flange, installation of the compression mold punch, its fastening with the separator and the formation of a monolithic impeller by pressing by applying pressure to an elastic punch, characterized in that annular blanks of composite material are laid between the layers of material for the back flange, the quantity of which is determined by strength . 2. A method of manufacturing an impeller of a compressor or fan from a composite material according to claim 1, characterized in that when stacking the ring blanks, each of them is rotated relative to the previous one by an angle of 360: n, where n is the number of ring blanks obtained based on the strength of the rear flange.

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