A high-efficiency device for saturated waste heat steam turbine

Abstract

This utility model discloses a high-efficiency device for a saturated waste heat steam turbine, relating to the field of steam turbine technology. It includes a turbine body with blade assemblies rotatably mounted inside. The high-efficiency device for a saturated waste heat steam turbine, as described in this utility model, utilizes the action of a buffer spring and the meshing of a fixed rack and transmission gear to allow the commutating blades to automatically adjust their guidance according to the pressure of the high-speed steam, thereby improving steam flow efficiency. Simultaneously, since the high-speed steam is never stably input, the buffer spring causes the commutating blades to slightly oscillate, resulting in blade vibration. This facilitates the shaking off of condensate on the commutating blades, further increasing the flow area of ​​the high-speed steam. The blade tip clearance loss is reduced by 40%, and the stage efficiency is increased by 6.8%. The Cr3C2-NiCr and WC-Co gradient coating improves erosion resistance by 3 times, maintaining a hardness of HV1200 at 650℃, thus extending the service life of the steam turbine.

Description

Technical Field

[0001] This utility model relates to the field of steam turbine technology, and more specifically, to a high-efficiency device for a saturated waste heat steam turbine. Background Technology

[0002] In the field of industrial production and energy utilization, the recovery and utilization of waste heat resources is a key path to achieve energy conservation and emission reduction and improve the overall efficiency of energy utilization. Among them, medium and low temperature saturated waste heat has become a key target for waste heat recovery due to its wide range of sources (such as process exhaust and wastewater waste heat in industries such as metallurgy, chemical industry, and building materials). The waste heat saturated steam turbine is a special steam turbine used in waste heat power generation systems. It uses saturated steam generated in industrial production processes as the working medium to convert the thermal energy of the steam into mechanical energy, which in turn drives a generator to generate electricity. In the existing technology, steam turbine devices for saturated waste heat are mostly based on structural modifications of conventional thermal power steam turbines. They do not fully consider the special characteristics of saturated waste heat, resulting in insufficient flow efficiency. After saturated steam enters the steam turbine, wet steam loss is likely to occur. The surplus steam resources in the converter steam network with continuously increasing pressure and flow rate cannot be efficiently utilized, leading to insufficient energy conversion efficiency. Utility Model Content

[0003] The main objective of this invention is to provide a high-efficiency device for saturated waste heat steam turbines, which can effectively solve the problems in the background art.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A high-efficiency device for a saturated waste heat steam turbine includes a steam turbine body, wherein a blade assembly is rotatably mounted inside the steam turbine body. The turbine body includes a fixed shell, both ends of which are fixedly connected to side shells, and one end of each side shell is fixedly connected to a connector. Multiple stator blades are fixedly connected inside the side shells. The stator blades include a fixed ring, one end of which is fixedly connected to a connecting frame. The fixed ring is fixedly connected to the inner wall of the side housing via the connecting frame. Multiple connecting rods are rotatably mounted on the outer surface of the fixed ring. A reversing blade is fixedly connected to the top of each connecting rod, and a transmission gear is fixedly connected to the bottom of each connecting rod. The transmission gear is rotatably mounted inside the fixed ring. A cavity is formed inside the fixed ring, and a movable sleeve is movably fitted inside the cavity. Multiple limiting grooves are formed inside the movable sleeve, and a fixed rack is fixedly connected to one side of the inner wall of each limiting groove. A buffer spring is fixedly connected to the side of the movable sleeve, and the buffer spring is located between the movable sleeve and the inner wall of the fixed ring. The side of the fixed rack meshes with the outer surface of the transmission gear.

[0005] Preferably, the blade assembly includes a rotating shaft, with multiple rotor blades fixedly sleeved at both ends of the rotating shaft, tail blades fixedly sleeved on the outer surfaces of both ends of the rotating shaft, and connecting flanges fixedly connected to both ends of the rotating shaft.

[0006] Preferably, the rotating shaft is rotatably mounted inside the fixed housing and the side housing, the diameter of the plurality of rotor blades gradually increases from the inside to the outside, the plurality of rotor blades and the plurality of stator blades are staggered and distributed inside the side housing, and the rotor blades are rotatably mounted on the side of the stator blades.

[0007] Preferably, the tail blade is a three-dimensional bending-torsion composite blade.

[0008] Preferably, the length of the tail blade is 1050 mm.

[0009] Preferably, the tail blades, rotor blades and stator blades are coated with a gradient of Cr3C2-NiCr and WC-Co.

[0010] Compared with the prior art, the present invention has the following beneficial effects: 1. Through the action of the buffer spring and the meshing action of the fixed rack and the transmission gear, the reversing blades can automatically adjust their guidance according to the pressure of the high-speed steam, thereby improving the steam flow efficiency. At the same time, since the high-speed steam cannot be stably input, the buffer spring causes the reversing blades to swing slightly, resulting in vibration of the reversing blades, which facilitates the shaking off of the condensate on the reversing blades, thereby increasing the flow area of ​​the high-speed steam. 2. A three-dimensional bending-torsion composite blade design was developed, and unsteady CFD simulation and genetic algorithm optimization were adopted. The tail blade height reached 1050mm (traditional 650mm), the tip clearance loss was reduced by 40%, and the stage efficiency was improved by 6.8%. 3. The tail blades, rotor blades and stator blades are coated with Cr3C2-NiCr and WC-Co gradient coatings by plasma spraying and laser remelting process, which improves the erosion resistance by 3 times and maintains the hardness of HV1200 at 650℃, thus improving the service life of the steam turbine. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the turbine body structure of this utility model; Figure 3 This is a schematic diagram of the blade assembly structure of this utility model; Figure 4 This is a schematic diagram of the tail blade structure of this utility model; Figure 5This is a schematic diagram of the stator blade structure of this utility model; Figure 6 This is a schematic diagram of the stator blade and rotor blade structure of this utility model.

[0012] The attached figures are labeled as follows: 1. Turbine body; 2. Blade assembly; 11. Fixed shell; 12. Side shell; 13. Connector; 14. Stator blade; 21. Rotating shaft; 22. Rotor blade; 23. Tail end blade; 24. Connecting flange; 141. Fixing ring; 142. Connecting frame; 143. Reversing blade; 144. Connecting rod; 145. Transmission gear; 146. Moving sleeve; 147. Buffer spring; 148. Limiting groove; 149. Fixed rack. Detailed Implementation

[0013] To make the technical problems, technical solutions and advantages of this utility model clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0014] As attached Figure 1 To be continued Figure 6 As shown, an embodiment of this utility model provides a high-efficiency device for a saturated waste heat steam turbine, including a turbine body 1 and a blade assembly 2, wherein the blade assembly 2 is rotatably installed inside the turbine body 1; like Figure 2 As shown, the turbine body 1 includes a fixed shell 11, a side shell 12 and stator blades 14. Both ends of the fixed shell 11 are fixedly connected to the side shell 12. One end of each side shell 12 is fixedly connected to a connector 13. Multiple stator blades 14 are fixedly connected inside the side shell 12. like Figure 5 As shown, the stator blade 14 includes a fixed ring 141. One end of the fixed ring 141 is fixedly connected to a connecting frame 142. The fixed ring 141 is fixedly connected to the inner wall of the side housing 12 through the connecting frame 142. Multiple connecting rods 144 are rotatably mounted on the outer surface of the fixed ring 141. A reversing blade 143 is fixedly connected to the top of the connecting rod 144. A transmission gear 145 is fixedly connected to the bottom of the connecting rod 144. The transmission gear 145 is rotatably mounted inside the fixed ring 141. A cavity is opened inside the fixed ring 141. A movable sleeve 146 is movably sleeved inside the cavity. Multiple limiting grooves 148 are opened inside the movable sleeve 146. A fixed rack 149 is fixedly connected to one side of the inner wall of the limiting groove 148. A buffer spring 147 is fixedly connected to the side of the movable sleeve 146. The buffer spring 147 is located between the movable sleeve 146 and the inner wall of the fixed ring 141. The side of the fixed rack 149 meshes with the outer surface of the transmission gear 145.

[0015] like Figure 3As shown, the blade assembly 2 includes a rotating shaft 21, with multiple rotor blades 22 fixedly sleeved at both ends of the rotating shaft 21, tail blades 23 fixedly sleeved on the outer surfaces of both ends of the rotating shaft 21, and connecting flanges 24 fixedly connected to both ends of the rotating shaft 21.

[0016] Specifically, superheated steam enters the waste heat turbine through a pipeline and flows sequentially through the rotor blades 22 and stator blades 14. When the steam flows through the stator blades 14, the cross-sectional area of ​​the channel increases, the steam pressure decreases, and the flow velocity increases sharply, converting thermal energy into kinetic energy. The steam expands in the blade channel, and the pressure and temperature decrease. The stator blades 14 spray high-speed steam onto the rotor blades 22 in a direction matching the movement direction of the rotor blades 22, driving the rotor to rotate and driving the rotor blades 22 to drive the rotating shaft 21 to rotate at high speed.

[0017] The rotating shaft 21 is rotatably installed inside the fixed shell 11 and the side shell 12. The diameter of the multiple rotor blades 22 gradually increases from the inside to the outside. The multiple rotor blades 22 and the multiple stator blades 14 are staggered inside the side shell 12. The rotor blades 22 are rotatably installed on the side of the stator blades 14.

[0018] Among them, the tail blade 23 is a three-dimensional bending and twisting composite blade.

[0019] The tail blade 23 has a length of 1050 mm.

[0020] Specifically, a three-dimensional bending-torsion composite blade design was developed, and unsteady CFD simulation and genetic algorithm optimization were adopted. The height of the tail blade 23 reached 1050mm compared to the traditional 650mm, the tip clearance loss was reduced by 40%, and the stage efficiency was improved by 6.8% (measured value).

[0021] Among them, the tail blade 23, rotor blade 22 and stator blade 14 are coated with Cr3C2-NiCr and WC-Co gradient coatings.

[0022] Specifically, the tail blade 23, rotor blade 22 and stator blade 14 are prepared with Cr3C2-NiCr and WC-Co gradient coatings by plasma spraying and laser remelting process, which improves the erosion resistance by 3 times and maintains the hardness of HV1200 at 650℃.

[0023] The working process of this utility model is as follows: Industrial waste heat first enters a waste heat boiler or evaporator to heat the working fluid inside the boiler. The working fluid undergoes a phase change from "water → saturated water → saturated steam → superheated steam," absorbing the thermal energy of the waste heat and transforming it into superheated steam with a certain pressure and temperature. The superheated steam enters the waste heat turbine through pipes and flows sequentially through rotor blades 22 and stator blades 14. When the steam flows through stator blades 14, the stator blades 14 spray high-speed steam onto the rotor blades 22 in a direction matching the movement of the rotor blades 22, driving the rotating shaft 21 to rotate. The rotor blades 22 drive the rotating shaft 21 to rotate at high speed, converting the "thermal energy" of the steam into the "mechanical work" of the rotor. The rotating shaft 21 is connected to the generator rotor through a coupling, transmitting the mechanical work to the generator. During this process, high-speed gas is injected onto the stator blades 14. The commutator blades 143, based on the high-speed steam pressure, are guided by the buffer springs 147. When the high-speed steam pressure decreases, the reaction force of the buffer springs 147 pushes the moving sleeve 146 to move within the cavity of the fixed ring 141. Through the meshing of the fixed rack 149 and the transmission gear 145, the commutator blades 143 rotate with the connecting rod 144, adjusting the orientation of the commutator blades 143 and thus the flow direction of the high-speed steam. Similarly, when the high-speed steam... When the pressure increases, the high-speed steam drives the reversing blade 143 to rotate. Through the meshing of the transmission gear 145, the moving sleeve 146 moves to the side, compressing the buffer spring 147. This allows the reversing blade 143 to automatically adjust its direction according to the pressure of the high-speed steam, thereby improving the steam flow efficiency. At the same time, since the high-speed steam cannot be stably input, the buffer spring 147 causes the reversing blade 143 to oscillate slightly, resulting in vibration of the reversing blade 143. This facilitates the shaking off of condensate on the reversing blade 143, thereby increasing the flow area of ​​the high-speed steam.

[0024] Finally, it should be noted that: the accompanying drawings of the embodiments disclosed in this utility model only involve the structures involved in the embodiments disclosed in this utility model. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this utility model can be combined with each other. The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A high-efficiency device for a saturated waste heat steam turbine, comprising a turbine body (1), characterized in that: The turbine body (1) is internally mounted with a blade assembly (2); The turbine body (1) includes a fixed shell (11), and side shells (12) are fixedly connected to both ends of the fixed shell (11). A connector (13) is fixedly connected to one end of each side shell (12). Multiple stator blades (14) are fixedly connected inside the side shell (12). The stator blade (14) includes a fixing ring (141), one end of which is fixedly connected to a connecting frame (142). The fixing ring (141) is fixedly connected to the inner wall of the side housing (12) through the connecting frame (142). Multiple connecting rods (144) are rotatably mounted on the outer surface of the fixing ring (141). A reversing blade (143) is fixedly connected to the top of the connecting rod (144), and a transmission gear (145) is fixedly connected to the bottom of the connecting rod (144). The transmission gear (145) is rotatably mounted inside the fixing ring (141). The fixed ring (141) has a cavity inside, and a movable sleeve (146) is movably sleeved inside the cavity. The movable sleeve (146) has multiple limiting grooves (148) inside. A fixed rack (149) is fixedly connected to one side of the inner wall of the limiting groove (148). A buffer spring (147) is fixedly connected to the side of the movable sleeve (146). The buffer spring (147) is located between the inner wall of the movable sleeve (146) and the fixed ring (141). The side of the fixed rack (149) meshes with the outer surface of the transmission gear (145).

2. The high-efficiency device for a saturated waste heat steam turbine according to claim 1, characterized in that: The blade assembly (2) includes a rotating shaft (21), with multiple rotor blades (22) fixedly sleeved at both ends of the rotating shaft (21), tail blades (23) fixedly sleeved on the outer surfaces of both ends of the rotating shaft (21), and connecting flanges (24) fixedly connected to both ends of the rotating shaft (21).

3. The high-efficiency device for a saturated waste heat steam turbine according to claim 2, characterized in that: The rotating shaft (21) is rotatably installed inside the fixed shell (11) and the side shell (12). The diameter of the multiple rotor blades (22) gradually increases from the inside to the outside. The multiple rotor blades (22) and the multiple stator blades (14) are staggered inside the side shell (12). The rotor blades (22) are rotatably installed on the side of the stator blades (14).

4. The high-efficiency device for a saturated waste heat steam turbine according to claim 2, characterized in that: The tail blade (23) is a three-dimensional bending-torsion composite blade.

5. The high-efficiency device for a saturated waste heat steam turbine according to claim 4, characterized in that: The length of the tail blade (23) is 1050 mm.

6. The high-efficiency device for a saturated waste heat steam turbine according to claim 2, characterized in that: The tail blade (23), rotor blade (22) and stator blade (14) are coated with Cr3C2-NiCr and WC-Co gradient coatings.

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