CN114909184A

CN114909184A - Impeller with pressure balance hole and turbine with same

Info

Publication number: CN114909184A
Application number: CN202110168885.6A
Authority: CN
Inventors: 彭杰伟; 冯金勇; 胡璐; 殷长春; 顾智超; 秦培军
Original assignee: Shanghai Qiyao Heavy Industry Co ltd; Shanghai Marine Diesel Engine Research Institute
Current assignee: Shanghai Qiyao Heavy Industry Co ltd; Shanghai Marine Diesel Engine Research Institute
Priority date: 2021-02-07
Filing date: 2021-02-07
Publication date: 2022-08-16

Abstract

The invention discloses an impeller with a pressure balancing hole and a turbine with the same. The impeller includes rim plate, blade and pressure balance hole, and the rim plate has along the convex central authorities of the axial direction of impeller arch, and the blade sets up to the rim plate along the circumferential direction interval of impeller, and the pressure balance hole runs through central authorities arch along the axial direction. According to the impeller provided by the invention, the pressure balance hole can reduce or eliminate axial force, the structure is simple, the efficiency is improved, the impeller is prevented from axially moving, the friction of the impeller is reduced, the strength of blades of the impeller is not influenced, and the vibration and noise are reduced.

Description

Impeller with pressure balance hole and turbine with same

Technical Field

The invention relates to the technical field of impeller machinery, in particular to an impeller with a pressure balance hole and a turbine with the same.

Background

In the rotating process of the impeller, the front and the back of a wheel disc of the impeller are subjected to different fluid pressures, so that the impeller is easy to move, the impeller is scratched, the sealing is damaged, vibration and noise are generated, even a bearing connected with the impeller is possibly burnt, and the phenomenon of shaft breakage occurs.

Accordingly, there is a need to provide an impeller having a pressure balancing hole and a turbine having the same to at least partially solve the above problems.

Disclosure of Invention

A series of concepts in a simplified form are introduced in the summary section, which is described in further detail in the detailed description section. This summary of the invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In order to at least partially solve the above-mentioned problems, according to a first aspect of the present invention, there is provided an impeller having a pressure balancing hole, the impeller including:

a wheel disc having a central boss protruding in an axial direction of the impeller;

blades arranged to the disk at intervals in a circumferential direction of the impeller; and

a pressure balance hole extending through the central boss in the axial direction.

According to the impeller provided by the invention, the impeller comprises a wheel disc, blades and a pressure balance hole, the wheel disc is provided with a central bulge which is convex along the axial direction of the impeller, the blades are arranged to the wheel disc at intervals along the circumferential direction of the impeller, and the pressure balance hole penetrates through the central bulge along the axial direction. Like this, the pressure balance hole can reduce or eliminate the axial force, simple structure, and the raising efficiency avoids the impeller to take place the axial float, reduces the clashing of impeller, guarantees that the blade intensity of impeller is not influenced, reduces vibration and noise.

Optionally, the pressure balance hole includes a first hole and a second hole communicating with each other, the wheel disc includes a first surface, the central boss includes a second surface opposite to the first surface in the axial direction, the first surface has an opening of the first hole, and the second surface has an opening of the second hole.

Optionally, the first hole extends obliquely inward in a direction toward a central axis of the impeller in the axial direction.

Optionally, the second bore extends in the axial direction.

Optionally, the blade comprises a root portion and a tip portion, the root portion being attached to the disk, wherein,

the thickness of the root portion is greater than the thickness of the tip portion; and/or the like, and/or,

the thickness of the blade increases and then decreases in the axial direction.

Optionally, the blades are twisted in a circumferential direction of the impeller, and/or the pressure balance holes are located between adjacent blades.

Optionally, the wheel disc further includes a positioning portion and a mounting hole, the positioning portion and the central protrusion are respectively located on two sides of the wheel disc, the positioning portion protrudes outward from the first surface along the axial direction, and the mounting hole penetrates through the positioning portion and the central protrusion along the axial direction.

The invention also provides a turbine comprising an impeller as described above.

According to the turbine of the invention, the turbine comprises an impeller, the impeller comprises a wheel disc, blades and a pressure balance hole, the wheel disc is provided with a central bulge protruding along the axial direction of the impeller, the blades are arranged to the wheel disc at intervals along the circumferential direction of the impeller, and the pressure balance hole penetrates through the central bulge along the axial direction. Like this, the pressure balance hole can reduce or eliminate the axial force, simple structure, and lifting efficiency avoids the impeller to take place the axial float, reduces the clashing of impeller, guarantees that the blade intensity of impeller is not influenced, reduces vibration and noise.

Optionally, the turbine still includes the sealed dish, the sealed dish with the impeller coaxial arrangement, the sealed dish with one of rim plate has the sealed arch, and another has the sealed recess, the sealed arch with the sealed recess cooperatees and forms the clearance, so that the sealed dish with form the labyrinth seal passageway between the rim plate.

Optionally, a plurality of sealing protrusions and a plurality of sealing grooves are included, each of which is arranged at intervals in a radial direction of the impeller.

Drawings

The following drawings of the invention are included to provide a further understanding of the invention. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles and apparatus of the invention. In the drawings there is shown in the drawings,

FIG. 1 is a perspective view of an impeller according to a preferred embodiment of the present invention;

FIG. 2 is a cross-sectional view of the impeller shown in FIG. 1; and

FIG. 3 is an exploded view of a portion of a turbine in accordance with a preferred embodiment of the present invention;

FIG. 4 is a cross-sectional view of the turbine shown in FIG. 3.

Description of reference numerals:

100: the impeller 110: wheel disc

112: center projection 113: weight-removing belt

114: second surface 115: positioning part

116: mounting hole 117: sealing projection

118: first surface 119: impeller locating surface

120: the blades 121: root of a tree

122: top 130: pressure balance hole

131: first hole 132: second hole

133: opening of first hole 134: opening of the second hole

200: the turbine 201: sealing disc

202: sealing surface 203: sealing groove

204: the pull rod 205: screw thread

206: connecting the boss 207: nut with a nut body

208: pull rod boss 209: external thread

210: internal thread 211: shaft

212: end surface 213 of shaft: shaft hole

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.

In the following description, for purposes of explanation, specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent that the invention is not limited to the specific details known to those skilled in the art to practice the invention. The following detailed description of the preferred embodiments of the present invention, however, the present invention may have other embodiments in addition to the detailed description, and should not be construed as being limited to the embodiments set forth herein.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention, and that the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. When the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The terms "upper", "lower", "front", "rear", "left", "right", and the like as used herein are for purposes of illustration only and are not intended to be limiting.

Ordinal words such as "first" and "second" are referred to herein merely as labels, and do not have any other meaning, such as a particular order, etc. Also, for example, the term "first component" does not itself imply the presence of "second component", and the term "second component" does not itself imply the presence of "first component".

In the following, specific embodiments of the present invention will be described in more detail with reference to the accompanying drawings, which illustrate representative embodiments of the invention and do not limit the invention.

As shown in fig. 1 and 2, the present invention provides an impeller 100 having a pressure balance hole 130, and the pressure balance hole 130 can adjust the pressure of fluid affecting the back surface of the impeller 100 to prevent the impeller 100 from generating a play in the axial direction.

The impeller 100 includes a disk 110, blades 120, and a pressure balancing hole 130, the blades 120 being connected to the disk 110. The wheel disc 110 may be configured as a generally solid of revolution structure. The disk 110 has a central protrusion 112 protruding in the axial direction of the impeller 100. The wheel disc 110 may be configured in a generally frustoconical configuration.

The blades 120 are provided to the disk 110 at intervals in the circumferential direction of the impeller 100. The blades 120 are evenly distributed on the disk 110 about the central axis a of the impeller 100. Preferably, the blades 120 and the disk 110 have chamfers therebetween to form a circular transition, so as to reduce stress applied to the blades 120, prevent stress concentration, and increase strength and rigidity of the blades 120.

The impeller 100 includes a plurality of blades 120, and the plurality of blades 120 are provided at intervals in a circumferential direction of the impeller 100. The plurality of blades 120 may be arranged to the central boss 112 at regular intervals in the circumferential direction of the impeller 100 to form a passage for fluid flow. The central protrusion 112 may include an arc-shaped section extending in the axial direction of the impeller 100, the arc-shaped section being turned in the circumferential direction of the impeller 100 to form the outer circumferential surface of the central protrusion 112. The plurality of blades 120 are provided to the arc-shaped section at intervals in the axial direction of the impeller 100. The disk 110 and the blades 120 may rotate together.

Alternatively, the impeller 100 may include 12 blades 120, and the 12 blades 120 may be arranged on the disk 110 at regular intervals in the circumferential direction of the impeller 100. Of course, the number of the blades 120 may be adjusted according to actual conditions, and the embodiment is not intended to be limited thereto. The blades 120 of the impeller 100 may be unequal in length, for example, the impeller 100 may include a portion of longer blades and a portion of shorter blades to accommodate different fluid flow conditions.

The adjacent blades 120 form a passage for fluid to flow between them, and can increase or decrease the pressure of the fluid. The impeller 100 may be used in a radial inflow turbine, and a high-pressure fluid may flow inward in a radial direction of the impeller 100, and the impeller 100 may reduce the pressure of the fluid. The high pressure fluid flows from the outer diameter edge of the disk 110 into between the blades 120, and the high pressure fluid flows inward in the radial direction of the impeller 100 to the center of the impeller 100 to be depressurized into a low pressure fluid. The impeller 100 may also be used in a centrifugal turbine, a low-pressure fluid may flow outward in a radial direction of the impeller 100, and the impeller 100 may increase the pressure of the fluid. Low-pressure fluid flows from the center of the disk 110 into between the blades 120, and the low-pressure fluid flows outward in the radial direction of the impeller 100 to the outer diameter edge of the impeller 100 to be pressurized into high-pressure fluid.

As shown in fig. 2, the wheel disc 110 may include a first surface 118 and the central protrusion 112 includes a second surface 114 opposite the first surface 118 in the axial direction of the impeller 100. Further, in the present embodiment, the "first surface 118" is a surface of the impeller 100 facing away from the blades 120, i.e., a wheel back of the impeller 100. The high pressure fluid may flow from the outer diameter edge of the impeller 100 radially inward of the impeller 100 and against the first surface 118, where the high pressure fluid applies an axial force to the impeller 100. In particular, the high pressure fluid may exert a force on the impeller 100 in a direction toward the blades 120. Accordingly, the present invention provides an impeller 100 having a pressure balancing hole 130, the pressure balancing hole 130 being capable of discharging fluid in close proximity to the first surface 118, reducing the amount of fluid that exerts an axial force on the impeller 100.

A pressure balancing hole 130 extends through the central boss 112 in the axial direction of the impeller 100 to vent high pressure fluid on the first surface 118 to balance the axial forces. The central protrusion 112 protrudes in the axial direction of the impeller 100. The pressure balance hole 130 includes two openings opposite in the axial direction of the impeller 100. The first surface 118 has one of the two openings of the pressure balancing hole 130 and the second surface 114 has the other of the two openings of the pressure balancing hole 130. In this way, the pressure balance hole 130 can communicate the back and front of the impeller 100, thereby forming a relief passage for fluid.

According to the impeller provided by the invention, the impeller comprises a wheel disc, blades and a pressure balance hole, the wheel disc is provided with a central bulge protruding along the axial direction of the impeller, the blades are arranged on the wheel disc at intervals along the circumferential direction of the impeller, and the pressure balance hole penetrates through the central bulge along the axial direction. Like this, the pressure balance hole can reduce or eliminate the axial force, simple structure, and the raising efficiency avoids the impeller to take place the axial float, reduces the clashing of impeller, guarantees that the blade intensity of impeller is not influenced, reduces vibration and noise.

Further, the pressure balance hole 130 includes a first hole 131 and a second hole 132, and the first hole 131 and the second hole 132 communicate. The intersection position of the first hole 131 and the second hole 132 can be adjusted according to the position and the angle of the holes, so that the processing difficulty of the holes is reduced. The first surface 118 and the second surface 114 may each be perpendicular to the central axis a of the impeller 100. Of course, the first surface 118 and the second surface 114 may also be disposed obliquely to the central axis a of the impeller 100. Alternatively, the first surface 118 and the second surface 114 may also be configured as curved surfaces to ensure strength. The first surface 118 and the second surface 114 face in opposite directions, respectively, in the axial direction of the impeller 100.

The first surface 118 has an opening 133 of the first hole 131 and the second surface 114 has an opening 134 of the second hole 132. Thus, the first and

second apertures

131, 132 may communicate the first and

second surfaces

118, 114. Fluid may flow from the first surface 118 to the second surface 114 through the first and

second apertures

131, 132, thereby expelling the fluid. Preferably, the opening 133 of the first hole 131 and the opening 134 of the second hole 132 may each be provided with a chamfer to prevent stress concentration at the orifice.

The impeller 100 may further include a plurality of pressure balance holes 130, the plurality of pressure balance holes 130 being arranged at intervals in a circumferential direction of the impeller 100 to penetrate the central protrusion 112, respectively. Thus, the plurality of pressure balance holes 130 may form a plurality of pressure relief passages, improving the efficiency of discharging fluid. The plurality of pressure balance holes 130 may be arranged at regular intervals in the circumferential direction of the impeller 100. The number of the blades 120 of the impeller 100 may be several times that of the pressure balance holes 130. The pressure balance holes 130 may be arranged offset from the blades 120 in the axial direction of the impeller 100. The pressure balance holes 130 may be located between adjacent blades 120 to further reduce the effect of the pressure balance holes 130 on the blades 120.

Preferably, the first hole 131 extends obliquely inward in the axial direction of the impeller 100 toward the direction of the central axis a of the impeller 100. The first hole 131 may have an angle with the central axis a of the impeller 100, for example, the angle between the first hole 131 and the central axis a of the impeller 100 is an acute angle. Thus, the inclined direction of the first hole 131 can match the shape of the arc-shaped section of the central protrusion 112, thereby ensuring the structural strength and reducing the processing difficulty.

The second hole 132 extends in the axial direction of the impeller 100. The central axis of the second bore 132 may be parallel to the central axis a of the impeller 100. In this way, the second holes 132 are connected to the first holes 131, so that the first holes 131 are prevented from penetrating out of the outer peripheral surface of the central protrusion 112, and the fluid on the first surface 118 is prevented from entering between the blades 120, so that the fluid on the first surface 118 is prevented from influencing the normal flow of the fluid between the blades 120, and the influence of the pressure balance holes 130 on the profile and strength of the blades 120 is reduced.

Returning now to FIG. 1, the blade 120 may include a root 121 and a tip 122, the root 121 being attached to the disk 110. In particular, the root portion 121 may be connected to the outer circumferential surface of the central protrusion 112. Preferably, the thickness of the root portion 121 may be greater than that of the tip portion 122. In this way, the blade 120 may have sufficient connection strength with the central protrusion 112 such that the connection position of the blade 120 with the disk 110 is not easily broken.

The high-pressure fluid may flow in a radial direction of the impeller 100. The high pressure fluid may flow inward in the radial direction of the impeller 100, and the high pressure fluid may also flow in the axial direction of the impeller 100 from the first surface 118 toward the second surface 114. Alternatively, the high-pressure fluid may flow outward in a radial direction of the impeller 100, and the high-pressure fluid may also flow in an axial direction of the impeller 100 from the second surface 114 toward the first surface 118.

The thickness of the blades 120 may increase and then decrease in the axial direction of the impeller 100. The thickness of the blade 120 increases and then decreases from the first surface 118 toward the second surface 114, or the thickness of the blade 120 increases and then decreases from the second surface 114 toward the first surface 118. Thus, the thickness of the vane 120 increases and then decreases in the flow direction of the fluid. That is, the thickness of the vane 120 at the middle position in the axial direction of the impeller 100 is large, and the thickness of the vane 120 at both sides in the axial direction of the impeller 100 is small. Thus, the vane 120 can guide the fluid and does not interfere the flow of the fluid, so that the high-pressure fluid can stably reduce the pressure.

Further, the blades 120 may be twisted in a circumferential direction of the impeller 100. In this way, the fluid may be caused to exert a force on the twisted portion of the blades 120, driving rotation of the impeller 100.

As shown in fig. 2, the wheel disc 110 further includes a deadweight belt 113, and the deadweight belt 113 is located on the first surface 118 as an impeller dynamic balance deadweight location. After the impeller 100 is machined, unbalance due to slight weight unevenness may occur due to material unevenness and machining error. Thus, the weight-reducing band 113 may be pre-manufactured during the machining of the impeller 100, and the mass of a particular location of the weight-reducing band 113 may be reduced after the machining of the impeller 100 is completed.

The wheel disc 110 further includes a positioning portion 115 and a mounting hole 116, and the positioning portion 115 and the central boss 112 are respectively located at both sides of the wheel disc 110. The positioning part 115 and the central boss 112 may be respectively located at both sides of the wheel disc 110 in the axial direction of the impeller 100. The positioning portion 115 may protrude outward from the first surface 118 in the axial direction of the impeller 100. The positioning portion 115 may be configured in a substantially cylindrical shape. The axial direction of the positioning portion 115 is parallel to the axial direction of the impeller 100.

The mounting hole 116 may be located at the center of the impeller 100. The mounting holes 116 may be configured as through holes of equal diameter or tapered holes, etc. The mounting hole 116 penetrates the positioning portion 115 and the central protrusion 112 in the axial direction of the impeller 100. Thus, the impeller 100 can be mounted through the mounting hole 116, and the positioning portion 115 performs a positioning function on the position of the impeller 100.

Specifically, as shown in fig. 3, the impeller 100 may be connected to the shaft 211 by a tie rod 204. The axis of the pull rod 204 coincides with the axis of the mounting hole 116. The shaft 211 may be configured to be substantially cylindrical. The shaft 211 may be located in the center of the sealing disk 201. The shaft 211 includes a shaft hole 213, and the center axis of the shaft hole 213 may coincide with the center axis of the mounting hole 116, so that the impeller 100 and the sealing disk 201 are coaxially disposed. The sealing disc 201 has a hole in the center so that the sealing disc 201 is annular as a whole, the shaft 211 can extend through the hole, and the sealing disc 201 is fixedly mounted on other stationary components such as a housing so that the axial directions of the sealing disc 201 and the shaft 211 coincide. The seal disk 201 is a stationary member. The impeller 100, the pull rod 204, and the shaft 211 are able to rotate together. The impeller 100, the tie rod 204, and the shaft 211 rotate about the central axis a relative to the seal disk 201.

The pull rod 204 may also extend through the shaft hole 213 of the shaft 211 and connect with the shaft hole 213. Preferably, the outer peripheral surface of the pull rod 204 has an external thread 209, the inner peripheral surface of the axial hole 213 has an internal thread 210 (both the external thread 209 and the internal thread 210 are drawn in simplified drawings for clarity of the page), and the external thread 209 of the pull rod 204 and the internal thread 210 of the axial hole 213 are engaged to couple the pull rod 204 and the seal disk 201 together.

The positioning portion 115 projects in the axial direction of the impeller 100 toward the direction of the seal disk 201. The positioning portion 115 may include an impeller positioning surface 119, the impeller positioning surface 119 being perpendicular to the central axis a of the impeller 100. The positioning portion 115 may further include an outer circumferential surface, and the outer circumferential surface of the positioning portion 115 is connected to the impeller positioning surface 119. Preferably, the outer circumferential surface of the positioning portion 115 may be smoothly connected with the impeller positioning surface 119 through one or more arcs to reduce stress of the wheel back.

As shown in connection with fig. 3, the shaft 211 may include an end surface 212, and the end surface 212 of the shaft 211 may face in the direction of the impeller 100. The impeller locating surface 119 and the end surface 212 of the shaft 211 may be in close contact to locate the impeller 100 and to take up the axial forces and torques of the impeller 100. The pull rod boss 208 is matched with the shaft 211 to play a role in positioning the impeller 100, reduce the back stress of the impeller 100, improve the strength distribution of the impeller 100 and improve the reliability of the impeller 100.

One portion of the pull rod 204 may be provided with threads and another portion of the pull rod 204 may not be provided with threads. For example, both ends of the tie rod 204 in the axial direction of the impeller 100 are provided with threads, and the middle portion of the tie rod 204 is not provided with threads. The tie rod 204 extends through the mounting hole 116 of the impeller 100. One end of the pull rod 204 is directly connected to the shaft 211 and the threads 205 (the threads 205 are drawn in simplified form for clarity of the page) on the other end of the pull rod 204 are connected to a nut 207 to attach the impeller 100 to the shaft 211. Optionally, the other end of the pull rod 204 is further provided with a connecting boss 206, and the connecting boss 206 can be inserted into the nut 207 to facilitate disassembly and assembly.

The second surface 114 of the central boss 112 is provided with a stepped counterbore that communicates with the mounting hole 116 as a connecting surface for coupling with the nut 207. The openings 134 of the second bore 132 may be spaced on the second surface 114 in a circumferential direction of the impeller 100 and disposed about the counterbore step.

Further, the seal disk 201 may also be a seal clearance fit with the impeller 100. One of the sealing disc 201 and the wheel disc 110 has a sealing projection 117 and the other has a sealing groove 203, the sealing projection 117 and the sealing groove 203 cooperating such that the sealing disc 201 and the wheel disc 110 form a sealing channel. In this way, the sealing protrusion 117 and the sealing groove 203 may prevent the fluid from flowing in a direction toward the center of the impeller 100 in the radial direction of the impeller 100, reducing the force applied by the fluid to the first surface 118.

The sealing channel formed by the sealing protrusion 117 and the sealing groove 203 can reduce the leakage amount and pressure of the fluid entering the first surface 118 and tightly attached to the first surface, and guide the leakage fluid at the first surface 118 back to the main flow through the pressure balance hole 130, thereby reducing the axial acting force of the fluid on the impeller 100, avoiding the impeller 100 from moving and rubbing, reducing vibration and noise, and avoiding the bearing connected with the impeller 100 from burning and the shaft breaking phenomenon.

Optionally, the sealing disc 201 comprises a sealing surface 202 facing the impeller 100, the sealing surface 202 being perpendicular to the central axis a of the impeller 100. The sealing surface 202 may have a sealing groove 203, and the sealing groove 203 may be configured as an annular groove. The first surface 118 of the wheel disc 110 may have a sealing bead 117, and the sealing bead 117 may be configured as an annular bead. The sealing protrusion 117 and the sealing groove 203 may cooperate, and the sealing protrusion 117 may be inserted into the sealing groove 203 such that the sealing surface 202 and the first surface 118 form a sealing channel, thereby blocking fluid flow in a direction toward the center of the impeller 100.

Further, the sealing surface 202 may have a plurality of sealing grooves 203, and the plurality of sealing grooves 203 may be arranged at intervals in the radial direction of the impeller 100. The first surface 118 has a plurality of sealing protrusions 117, and the plurality of sealing protrusions 117 may be arranged at intervals in a radial direction of the impeller 100. The plurality of sealing protrusions 117 and the plurality of sealing grooves 203 may be engaged, and the plurality of sealing protrusions 117 may be inserted into the plurality of sealing grooves 203, respectively, to form an axial labyrinth structure, so that a sealing passage is formed between the sealing disc 201 and the disk 110.

Of course, the sealing surface 202 may also have the sealing protrusion 117, the first surface 118 may have the sealing groove 203, and the sealing protrusion 117 and the sealing groove 203 may cooperate, which is not intended to be limiting in the present embodiment.

The diameter and number of the pressure balance holes 130 may also be matched to the size and number of the sealing protrusions 117 or the sealing grooves 203 to reduce fluid leakage to ensure balance of axial forces. The deduplication tape 113 may be closer to the central axis a of the impeller 100 than the seal protrusion 117 or the seal groove 203 in the radial direction of the impeller 100. I.e., the diameter of the deduplication tape 113 is smaller than the diameter of the sealing protrusion 117 or the sealing groove 203.

Further, the deduplication tape 113 may also be farther from the central axis a of the impeller 100 than the seal protrusion 117 or the seal groove 203 in the radial direction of the impeller 100. I.e., the diameter of the deduplication tape 113 is larger than the diameter of the sealing protrusion 117 or the sealing groove 203.

According to the impeller 100 of the present invention, the impeller 100 comprises the pressure balance hole 130, the pressure balance hole 130 can reduce or eliminate the axial force, maintain the balance of the axial force of the impeller 100, and can weaken the flow influence of the leakage on the fluid, improve the efficiency of the impeller 100, and ensure that the strength of the blade 120 is not influenced.

The invention also provides a turbine 200, the turbine 200 comprising the impeller 100 described above.

According to the turbine of the invention, the turbine comprises an impeller, the impeller comprises a wheel disc, blades and a pressure balance hole, the wheel disc is provided with a central bulge protruding along the axial direction of the impeller, the blades are arranged to the wheel disc at intervals along the circumferential direction of the impeller, and the pressure balance hole penetrates through the central bulge along the axial direction. Like this, the pressure balance hole can reduce or eliminate the axial force, simple structure, and the raising efficiency avoids the impeller to take place the axial float, reduces the clashing of impeller, guarantees that the blade intensity of impeller is not influenced, reduces vibration and noise.

As shown in fig. 3 and 4, the turbine 200 further includes a seal disk 201, and as described above, the seal disk 201 is disposed coaxially with the impeller 100. The impeller 100 may be connected to the shaft 211 by a tie rod 204. The pull rod 204 may extend through the mounting hole 116 of the impeller 100 and connect with the shaft 211. The shaft 211 includes a shaft hole 213, and a central axis of the shaft hole 213 may coincide with a central axis of the mounting hole 116, so that the impeller 100 and the shaft 211 are coaxially disposed.

The pull rod 204 may be connected to the shaft hole 213. Preferably, the outer circumferential surface of the drawbar 204 has an external thread 209, the inner circumferential surface of the shaft hole 213 has an internal thread 210, and the external thread 209 of the drawbar 204 and the internal thread 210 of the shaft hole 213 are engaged to couple the drawbar 204 and the shaft 211 together.

The sealing disc 201 has a hole in the center so that the sealing disc 201 is annular as a whole, the shaft 211 can extend through the hole, and the sealing disc 201 is fixedly mounted on other stationary components such as a housing so that the axes of the sealing disc 201 and the shaft 211 coincide. The seal disk 201 is a stationary member. The impeller 100, the pull rod 204, and the shaft 211 are able to rotate together. The impeller 100, the tie rod 204, and the shaft 211 rotate about the central axis a relative to the seal disk 201.

The positioning portion 115 protrudes in the axial direction of the impeller 100 toward the direction of the seal disk 201. The positioning portion 115 may include an impeller positioning surface 119, the impeller positioning surface 119 being perpendicular to the central axis a of the impeller 100. The positioning portion 115 may further include an outer circumferential surface, and the outer circumferential surface of the positioning portion 115 is connected to the impeller positioning surface 119. Preferably, the outer circumferential surface of the positioning portion 115 may be smoothly connected with the impeller positioning surface 119 through one or more arcs to reduce stress of the wheel back.

The shaft 211 may include an end surface 212, and the end surface 212 of the shaft 211 may face in the direction of the impeller 100. The impeller locating surface 119 and the end surface 212 of the shaft 211 may be in close contact to locate the impeller 100 and to take up the axial forces and torques of the impeller 100. The pull rod boss 208 is matched with the shaft 211 to play a role in positioning the impeller 100, reduce the back stress of the impeller 100, improve the strength distribution of the impeller 100 and improve the reliability of the impeller 100.

A portion of the drawbar 204 may be threaded and another portion of the drawbar 204 may be unthreaded. For example, both ends of the tie rod 204 in the axial direction of the impeller 100 are provided with threads, and the middle portion of the tie rod 204 is not provided with threads. The tie rod 204 extends through the mounting hole 116. One end of the tie rod 204 is directly connected to the shaft 211 and the threads 205 on the other end of the tie rod 204 are connected to the nut 207 to attach the impeller 100 to the shaft 211.

The seal disk 201 is in sealing clearance fit with the impeller 100. One of the seal plate 201 and the wheel disc 110 has a seal projection 117 and the other has a seal groove 203, the seal projection 117 and the seal groove 203 cooperating such that a seal channel is formed between the seal plate 201 and the wheel disc 110. In this way, the sealing protrusion 117 and the sealing groove 203 may prevent the fluid from flowing in a direction toward the center of the impeller 100 along the radial direction of the impeller 100, reduce the force applied by the fluid to the first surface 118, reduce the amount of fluid leakage, and ensure the high efficiency of the impeller 100.

The seal disk 201 includes a sealing surface 202 facing the impeller 100, the sealing surface 202 being perpendicular to the central axis a of the impeller 100. The sealing surface 202 may have a sealing groove 203, and the sealing groove 203 may be configured as an annular groove. The first surface 118 of the wheel disc 110 may have a sealing bead 117, and the sealing bead 117 may be configured as an annular bead. The sealing protrusion 117 and the sealing groove 203 may cooperate to form a gap, and the sealing protrusion 117 may be inserted into the sealing groove 203 such that a sealing channel is formed between the sealing surface 202 and the first surface 118, thereby blocking the fluid from flowing in a direction toward the center of the impeller 100.

Further, the sealing surface 202 may have a plurality of sealing grooves 203, and the plurality of sealing grooves 203 may be arranged at intervals in a radial direction of the impeller 100. The first surface 118 has a plurality of sealing protrusions 117, and the plurality of sealing protrusions 117 may be arranged at intervals in a radial direction of the impeller 100. The plurality of sealing protrusions 117 and the plurality of sealing grooves 203 may be fitted, and the plurality of sealing protrusions 117 may be inserted into the plurality of sealing grooves 203, respectively, such that a labyrinth passage is formed between the sealing disc 201 and the wheel disc 110.

Of course, the sealing surface 202 of the gland plate 201 may also have a sealing protrusion 117, the first surface 118 of the wheel disc 110 may have a sealing groove 203, and the sealing protrusion 117 and the sealing groove 203 may cooperate to form a gap such that a labyrinth passage is formed between the gland plate 201 and the wheel disc 110, which is not intended to be limiting in this embodiment. The arrangement of the sealing projection 117 and the sealing groove 203 may also be adjusted, for example, the sealing projection 117 and the sealing groove 203 may also jointly form a stepped labyrinth seal structure.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Terms such as "part," "section," and the like, appearing herein may refer to either a single component or a combination of components. Terms such as "mounted," "disposed," and the like, as used herein, may refer to one component as being directly attached to another component or one component as being attached to another component through intervening components. Features described herein in one embodiment may be applied to another embodiment, either alone or in combination with other features, unless the feature is otherwise inapplicable or otherwise stated in the other embodiment.

The present invention has been described in terms of the above embodiments, but it should be understood that the above embodiments are for purposes of illustration and description only and are not intended to limit the invention to the scope of the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the above embodiments, and that many variations and modifications may be made in accordance with the teaching of the present invention, which variations and modifications fall within the scope of the present invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. An impeller having a pressure balancing hole, the impeller comprising:

blades provided to the wheel disc at intervals in a circumferential direction of the impeller; and

2. The impeller of claim 1, wherein the pressure balancing hole includes a first hole and a second hole in communication, the disk includes a first surface, the central boss includes a second surface opposite the first surface in the axial direction, the first surface has an opening of the first hole, and the second surface has an opening of the second hole.

3. The impeller of claim 2, wherein the first bore extends obliquely inwardly in the axial direction towards a central axis of the impeller.

4. The impeller of claim 2, wherein the second bore extends in the axial direction.

5. The impeller of claim 1, wherein said blades include a root portion and a tip portion, said root portion being connected to said disk, wherein,

the root portion has a thickness greater than a thickness of the tip portion; and/or the like, and/or,

the thickness of the blade increases and then decreases in the axial direction.

6. The impeller according to claim 1, characterized in that said blades are twisted in the circumferential direction of the impeller and/or said pressure balancing holes are located between adjacent said blades.

7. The impeller of claim 2, wherein the wheel disc further comprises a positioning portion and a mounting hole, the positioning portion and the central protrusion are respectively located on both sides of the wheel disc, the positioning portion protrudes outward from the first surface in an axial direction, and the mounting hole penetrates through the positioning portion and the central protrusion in the axial direction.

8. A turbine, characterized in that it comprises an impeller according to any one of claims 1-7.

9. The turbine of claim 8, further comprising a seal disk disposed coaxially with the impeller, one of the seal disk and the disk having a seal projection and the other having a seal groove, the seal projection and the seal groove cooperating to form a gap such that a labyrinth passage is formed between the seal disk and the disk.

10. The turbine according to claim 9, comprising a plurality of seal projections and a plurality of seal grooves each arranged at intervals in a radial direction of the impeller.