A water delivery device for a boiler system

Abstract

The invention discloses a water conveying device for a boiler system, wherein the centrifugal pump rotor comprises a front disc (1), a rear disc (2), and blades (3), wherein a plurality of blades are evenly distributed along the circumferential direction and connected between the front disc and the rear disc, wherein the front disc has a water inlet, and the blades have a leading edge (31), a trailing edge (32), and a top edge (33), wherein the top edge is connected to the inner side surface of the front disc, and the leading edge is located upstream of the trailing edge, and wherein the device is characterized in that: the inner side surface of the front disc has a step portion (4), the connection between the inner side surface of the front disc and the top edge is a connecting portion (P), the length of the connecting portion is much smaller than the length of the top edge or the connecting portion is a connecting point, the step portion is located at the radial outer end of the connecting portion, and a confluence space (S) is formed between the inner side surface of the front disc and the top edge, and the confluence space is located at the radial inner end of the connecting portion. The invention can effectively improve the anti-cavitation performance of the centrifugal pump, reduce the flow loss of the centrifugal pump, thereby improving the overall performance of the centrifugal pump, and ensuring the stability of the conveying working condition of the boiler system.

Description

Technical Field

[0001] The invention relates to the technical field of boiler systems, and in particular to a water conveying device for a boiler system. Background Art

[0002] like Figure 1 As shown, the boiler feed water, steam circulation and sewage discharge subsystems of the boiler system include a variety of delivery pumps, such as feed water pumps, deaerator water pumps, sewage pumps, steam pumps, etc. The delivery pumps are mainly centrifugal pumps.

[0003] The turbine rotor structure of a centrifugal pump includes a front disc, a rear disc, and blades. A plurality of blades are evenly distributed along the circumference and connected between the front disc and the rear disc. The front disc has a water inlet. The blades have a leading edge, a trailing edge, and a top edge. The top edge is connected to the inner side of the front disc, and the leading edge is located upstream of the trailing edge. However, the existing turbine rotor has problems such as the need to further improve the anti-cavitation performance and large flow loss. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a water delivery device for a boiler system, which is designed through the step portion of the centrifugal pump rotor, the step portion is located at the radial outer end of the connection portion P, and the inner side surface of the front disk and the top edge form a confluence space S, the confluence space S is located at the radial inner end of the connection portion P, and the step portion includes a plurality of steps, so that the turbine rotor (impeller) has a step-variable enlarged space at its outlet, which can effectively improve the anti-cavitation performance of the centrifugal pump, reduce the flow loss of the centrifugal pump, and thus improve the overall performance of the centrifugal pump. Through the design of the confluence space S and the convex portion, the flow diversion performance at the blade inlet can be improved, thereby reducing the flow loss of the centrifugal pump and ensuring the stability of the delivery working condition of the boiler system.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A water delivery device for a boiler system, comprising a centrifugal pump, wherein the rotor of the centrifugal pump comprises a front disc (1), a rear disc (2), and blades (3), wherein a plurality of blades are evenly distributed along the circumferential direction and connected between the front disc and the rear disc, wherein the front disc has a water inlet, wherein the blades have a leading edge (31), a trailing edge (32), and a top edge (33), wherein the top edge is connected to the inner side surface of the front disc, wherein the leading edge is located upstream of the trailing edge, and wherein the characteristic is that: the inner side surface of the front disc has a step portion (4), wherein the connection between the inner side surface of the front disc and the top edge is a connection portion (P), wherein the length of the connection portion is much smaller than the length of the top edge (33) or the connection portion is a connection point, wherein the step portion is located at the radial outer end of the connection portion, wherein a confluence space (S) is formed between the inner side surface of the front disc and the top edge, and wherein the confluence space is located at the radial inner end of the connection portion.

[0007] Furthermore, the step portion (4) comprises a plurality of steps (41), wherein the plurality of steps is 3 to 8 steps; the step portion causes the thickness of the front disc (1) to gradually decrease from the connection portion (P) to the turbine rotor outlet radius R.

[0008] Furthermore, the blade (3) has a raised portion (34), and the raised portion is formed between the top edge (33) and the leading edge (31), the raised end point of the raised portion is located at the beginning of the confluence space (S), and the confluence space is a tapered structure along the water flow direction; the leading edge is an arc-shaped raised structure, and the arc-shaped raised structure extends in the axial direction of the turbine rotor.

[0009] Furthermore, the trailing edge (32) is arranged to be inclined relative to the axis of the turbine rotor, and the inclination angle a=5-15°; the radius of the intersection of the trailing edge (32) and the top edge (33) is smaller than the radius of the intersection of the trailing edge and the rear disc.

[0010] Furthermore, the turbine rotor has an outlet radius R, and the connecting portion (P) has a radius R1, where R1=(0.70-0.90)R.

[0011] Furthermore, the protrusion (34) has a radius R2, where R2=(0.50-0.70)R.

[0012] A boiler system comprises the centrifugal pump for the boiler system, wherein the centrifugal pump is a feed water pump, a steam pump or a sewage pump.

[0013] The present invention is a water conveying device for a boiler system. The step portion of the centrifugal pump rotor is designed. The step portion is located at the radial outer end of the connection portion P. A confluence space S is formed between the inner side surface and the top edge of the front disk. The confluence space S is located at the radial inner end of the connection portion P. The step portion includes a plurality of steps, so that the turbine rotor (impeller) has a step-variable enlarged space at its outlet, which can effectively improve the anti-cavitation performance of the centrifugal pump, reduce the flow loss of the centrifugal pump, and thus improve the overall performance of the centrifugal pump. The design of the confluence space S and the convex portion can improve the flow diversion performance at the blade inlet, thereby reducing the flow loss of the centrifugal pump and ensuring the stability of the conveying working condition of the boiler system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of a boiler system in the prior art;

[0015] Figure 2 This is a schematic diagram of the structure of a centrifugal pump rotor used in a boiler system of the present invention;

[0016] Figure 3 The figure is a schematic diagram of the structure of the centrifugal pump rotor used in the boiler system of the present invention.

[0017] In the figure: front disc 1, rear disc 2, blade 3, step portion 4, leading edge 31, trailing edge 32, front disc side top edge 33, protrusion 34, step 41, connection portion / connection point P, and confluence space S. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0020] like Figure 2-3 As shown, a water conveying device for a boiler system includes a centrifugal pump, the rotor of the centrifugal pump includes a front disk 1, a rear disk 2, and blades 3, a plurality of blades 3 are evenly distributed along the circumferential direction and connected between the front disk 1 and the rear disk 2, the front disk 1 has a water inlet, the blades 3 have a leading edge 31, a trailing edge 32, and a top edge 33, the top edge 33 is connected to the inner side surface of the front disk 1, the leading edge 31 is located upstream of the trailing edge 32, and is characterized in that: the inner side surface of the front disk 1 has a step portion 4, the connection between the inner side surface of the front disk 1 and the top edge 33 is a connection portion P, the length of the connection portion P is much smaller than the length of the top edge 33 or the connection portion P is a connection point, the step portion 4 is located at the radial outer end of the connection portion P, a confluence space S is formed between the inner side surface of the front disk 1 and the top edge 33, and the confluence space S is located at the radial inner end of the connection portion P.

[0021] Furthermore, the step portion 4 includes a plurality of steps 41 , and the plurality of steps 41 is 3-6 steps 41 ; the step portion 4 makes the thickness of the front disk 1 gradually decrease from the connection portion P to the turbine rotor (impeller) outlet radius R.

[0022] The present invention provides a water conveying device for a boiler system. The step portion 4 of the centrifugal pump rotor is designed. The step portion 4 is located at the radial outer end of the connecting portion P. A confluence space S is formed between the inner side surface of the front disk 1 and the top edge 33. The confluence space S is located at the radial inner end of the connecting portion P. The step portion 4 includes a plurality of steps 41, so that the turbine rotor (impeller) has a stepped enlarged space at its outlet, which can effectively improve the anti-cavitation performance of the centrifugal pump and reduce the flow loss of the centrifugal pump, thereby improving the overall performance of the centrifugal pump and ensuring the stability of the conveying working condition of the boiler system.

[0023] Furthermore, the blade 3 has a protrusion 34, and the protrusion 34 is formed between the top edge 33 and the leading edge 31, and the protrusion end point of the protrusion 34 is located at the beginning of the confluence space S, and the confluence space S is a tapered structure along the water flow direction. The leading edge 31 is an arc-shaped protrusion structure, and the arc-shaped protrusion structure extends toward the axis direction of the turbine rotor.

[0024] Furthermore, the trailing edge 32 is tilted relative to the axis of the turbine rotor, and the tilt angle a=5-15°, preferably 9-11°; the radius of the intersection of the trailing edge 32 and the top edge 33 is smaller than the radius of the intersection of the trailing edge 32 and the rear disk 2.

[0025] Further, the turbine rotor (impeller) has an outlet radius R, and the connecting portion P has a radius R1, R1=(0.75-0.85)R, preferably, R1=0.80R.

[0026] Further, the protrusion 34 has a radius R2, R2=(0.55-0.65)R, preferably, R2=0.60R.

[0027] The water conveying device for a boiler system of the present invention can improve the flow guiding performance at the inlet of the blade 3 through the design of the confluence space S and the protrusion 34 of the centrifugal pump rotor, thereby reducing the flow loss of the centrifugal pump and ensuring the stability of the conveying working condition of the boiler system.

[0028] The present invention is a water conveying device for a boiler system. The step portion 4 of the centrifugal pump rotor is designed. The step portion 4 is located at the radial outer end of the connection portion P. A confluence space S is formed between the inner side surface of the front disc 1 and the top edge 33. The confluence space S is located at the radial inner end of the connection portion P. The step portion 4 includes a plurality of steps 41, so that the turbine rotor (impeller) has a step-variable enlarged space at its outlet, which can effectively improve the anti-cavitation performance of the centrifugal pump, reduce the flow loss of the centrifugal pump, and thus improve the overall performance of the centrifugal pump. Through the design of the confluence space S and the protrusion 34, the flow guiding performance at the inlet of the blade 3 can be improved, thereby reducing the flow loss of the centrifugal pump and ensuring the stability of the conveying working condition of the boiler system.

[0029] The above-mentioned implementation modes are for explanation of the present invention rather than limitation of the present invention. It can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A water delivery device for a boiler system, comprising a centrifugal pump, wherein the rotor of the centrifugal pump comprises a front disc (1), a rear disc (2), and blades (3), wherein a plurality of blades are evenly distributed along the circumference and connected between the front disc and the rear disc, wherein the front disc has a water inlet, and wherein the blades have a leading edge (31), a trailing edge (32), and a top edge (33), wherein the top edge is connected to the inner side surface of the front disc, and the leading edge is located upstream of the trailing edge, wherein: The inner side surface of the front disk has a step portion (4), the connection between the inner side surface of the front disk and the top edge is a connection portion (P), the length of the connection portion is much smaller than the length of the top edge (33) or the connection portion is a connection point, the step portion is located at the radial outer end of the connection portion, and a confluence space (S) is formed between the inner side surface of the front disk and the top edge, and the confluence space is located at the radial inner end of the connection portion. The step portion (4) comprises a plurality of steps (41); the step portion causes the thickness of the front disc (1) to gradually decrease from the connection portion (P) to the turbine rotor outlet radius R, The blade (3) has a raised portion (34), and the raised portion is formed between the top edge (33) and the leading edge (31), the raised end point of the raised portion is located at the beginning of the confluence space (S), and the confluence space is a gradually contracting structure along the water flow direction; the leading edge is an arc-shaped raised structure, and the arc-shaped raised structure extends toward the axis direction of the turbine rotor. The trailing edge (32) is tilted relative to the axis of the turbine rotor, and the tilt angle a=5-15°; the radius of the intersection of the trailing edge (32) and the top edge (33) is smaller than the radius of the intersection of the trailing edge and the rear disc.

2. A water delivery device for a boiler system according to claim 1, characterized in that: The turbine rotor has an outlet radius R, and the connecting portion (P) has a radius R1, R1=(0.70-0.90)R.

3. A water delivery device for a boiler system according to claim 2, characterized in that: The protrusion (34) has a radius R2, R2=(0.50-0.70)R.

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