Sealing structure of runner chamber expansion joint of water turbine

Abstract

The utility model relates to the technical field of water turbines, and discloses a sealing structure of a runner chamber expansion joint of a water turbine, which comprises a runner chamber, a draft tube flange and an expansion joint arranged between the runner chamber and the draft tube flange, a pressing plate is arranged on the outer side of the expansion joint, and a first sealing groove is arranged between the draft tube flange and the expansion joint. A first sealing ring is arranged in the first sealing groove, a second sealing groove is formed between the runner chamber and the expansion joint, and a second sealing ring is arranged in the second sealing groove; a third sealing groove is formed in the contact position of the runner chamber, the telescopic joint and the pressing plate, the cross section of the third sealing groove is of a triangular structure, and three sealing rings are arranged in the third sealing groove. According to the utility model, four sealing structures are formed between the runner chamber and the expansion joint, so that the better water stopping effect is obviously improved, and the water leakage condition is eliminated.

Description

Technical Field

[0001] The utility model relates to the technical field of water turbines, and particularly relates to a sealing structure of an expansion joint of a runner chamber of a water turbine. Background Art

[0002] In the structural design of a bulb tubular water turbine, an expansion joint is usually provided between the runner chamber and the draft tube flange, and a rubber sealing ring is generally used to seal between the expansion joint and the draft tube flange. For the existing tubular water turbine, a rubber sealing ring with a diameter of Φ16 - Φ18mm is generally used to seal between the runner chamber and the expansion joint, and it is pressed tightly by a circle of pressing plates outside. This sealing structure uses the compression deformation of the sealing ring to fill the gap between the expansion joint and the runner chamber to achieve the purpose of water stoppage. During the operation of the hydro-generator unit, due to vibration or corrosion, dimensional deviation of the sealing groove, the local compression amount of the expansion joint seal is insufficient, resulting in easy leakage of the single sealing structure and low reliability. Therefore, it is necessary to optimize and improve the existing sealing structure. Summary of the Utility Model

[0003] The purpose of the utility model is to solve the above problems, provide a sealing structure of an expansion joint of a runner chamber of a water turbine, improve the sealing performance, significantly improve the water stoppage effect, and eliminate the leakage situation.

[0004] To achieve the above purpose, the technical scheme adopted by the utility model is as follows: A sealing structure of an expansion joint of a runner chamber of a water turbine, including a runner chamber, a draft tube flange, and an expansion joint provided between the runner chamber and the draft tube flange. A pressing plate is provided on the outer side of the expansion joint. A first sealing groove is provided between the draft tube flange and the expansion joint, and a first sealing ring is arranged in the first sealing groove. A second sealing groove is provided between the runner chamber and the expansion joint, and a second sealing ring is arranged in the second sealing groove. A third sealing groove is formed at the contact position between the runner chamber and the expansion joint and the pressing plate. The cross-section of the third sealing groove is a triangular structure, and three sealing rings are arranged in the third sealing groove.

[0005] Further, the three sealing rings include a third sealing ring, a fourth sealing ring, and a fifth sealing ring. The fourth sealing ring is arranged inside the third sealing ring, and the fifth sealing ring is arranged outside the third sealing ring.

[0006] Further, the first sealing ring is an O-shaped sealing ring with a diameter of Φ9mm.

[0007] Further, the second sealing ring is an O-shaped sealing ring with a diameter of Φ13mm.

[0008] Further, the third sealing ring, the fourth sealing ring and the fifth sealing ring are all O-shaped sealing rings. The diameter of the third sealing ring is Φ18mm, the diameter of the fourth sealing ring is Φ6mm, and the diameter of the fifth sealing ring is Φ8mm.

[0009] Due to the adoption of the above technical solution, the utility model has the following beneficial effects:

[0010] In this embodiment of the utility model, a second sealing ring is arranged in the second sealing groove between the runner chamber and the expansion joint, and three sealing rings are arranged in the third sealing groove with a triangular cross-section formed by the runner chamber, the expansion joint and the pressing plate, forming a four-sealing structure, ensuring the sealing compression amount of the expansion joint, significantly improving the water-stop effect and eliminating the water leakage situation. Description of the Drawings

[0011] Figure 1 It is a schematic structural diagram of a sealing structure of a runner chamber expansion joint of a water turbine of the utility model;

[0012] In the figure: 1 - runner chamber, 2 - expansion joint, 3 - draft tube flange, 4 - pressing plate, 5 - first sealing groove, 6 - first sealing ring, 7 - second sealing groove, 8 - second sealing ring, 9 - third sealing groove, 10 - third sealing ring, 11 - fourth sealing ring, 12 - fifth sealing ring. Detailed Embodiment

[0013] In order to enable those skilled in the art of this technology to better understand the solution of the utility model, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the utility model belongs. The terms used in the specification of the utility model herein are only for the purpose of describing specific embodiments and are not intended to limit the utility model. The terms "first", "second", etc. in the specification and claims of the utility model and the above drawings are used to distinguish different objects and are not used to describe a specific order. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices.

[0014] References to "embodiments" in this document mean that the specific features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present utility model. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0015] As Figure 1 shown, a sealing structure of an expansion joint of a runner chamber of a water turbine includes a runner chamber 1, a draft tube flange 3, an expansion joint 2, and a pressing plate 4. The draft tube flange 3 is provided at the rear end of the runner chamber 1. An expansion joint 2 is provided between the runner chamber 1 and the draft tube flange 3. A pressing plate 4 is provided outside the expansion joint 2. A first sealing groove 5 is provided between the draft tube flange 3 and the expansion joint 2. A first sealing ring 6 is provided in the first sealing groove 5. The first sealing ring 6 is an O-ring, and the diameter of the O-ring is Φ9 mm. A second sealing groove 7 is provided between the runner chamber 1 and the expansion joint 2. A second sealing ring 8 is provided in the second sealing groove 7. The second sealing ring 8 is an O-ring, and the diameter of the O-ring is Φ13 mm. Since the sealing groove is prone to local corrosion and dimensional changes during use, and the local compression amount is insufficient resulting in water leakage, the diameter of this sealing ring is increased to Φ13 mm to compensate for the influence of dimensional changes in the sealing groove, ensure the compression amount, and effectively improve the water leakage problem caused by dimensional changes in the sealing groove. A third sealing groove 9 is formed at the contact positions between the runner chamber 1, the expansion joint 2, and the pressing plate 4. The cross-section of the third sealing groove 9 is a triangular structure, and three sealing rings are provided in the third sealing groove 9.

[0016] The three sealing rings include a third sealing ring 10, a fourth sealing ring 11, and a fifth sealing ring 12. The fourth sealing ring 11 is provided inside the third sealing ring 10, and the fifth sealing ring 12 is provided outside the third sealing ring 10. The third sealing ring 10, the fourth sealing ring 11, and the fifth sealing ring 12 are all O-rings. The diameter of the third sealing ring 10 is Φ18 mm, the diameter of the fourth sealing ring 11 is Φ6 mm, and the diameter of the fifth sealing ring 12 is Φ8 mm. Setting three sealing rings at the triangular seal of the pressing plate 4 can well compensate for the influence of compression amount changes caused by vibration, ensure the sealing effect, significantly improve the water stop effect, and eliminate water leakage.

[0017] During installation, the expansion joint 2 and the draft tube flange 3 are fastened by bolts to provide the pressing force for the first sealing ring 6 in the first sealing groove 5, causing the first sealing ring 6 to be extruded and deformed to fill the sealing gap, ensuring a good sealing effect between the first sealing ring 6 and the draft tube flange 3. The expansion joint 2 and the pressing plate 4 are fastened by bolts, and the pressing plate 4 is used to press the three sealing rings in the triangular sealing groove. Moreover, the extrusion force generated by the expansion joint 2 causes the second sealing ring 8 in the second sealing groove 7 to be compressed and deformed to fill the gap. Four sealing structures are formed between the runner chamber 1 and the expansion joint 2, improving the sealing performance and avoiding water leakage problems caused by vibration or changes in the size of the sealing groove, eliminating the water leakage situation.

[0018] The above has generally described the present utility model in detail. However, based on the present utility model, some modifications or improvements can be made, which are obvious to those of ordinary skill in the technical field. Therefore, modifications or improvements that do not depart from the spirit of the present utility model are within the protection scope of the present utility model.

Claims

1. A sealing structure of a turbine runner chamber expansion joint, comprising a runner chamber, a draft tube flange, and an expansion joint arranged between the runner chamber and the draft tube flange, a pressure plate is arranged on the outer side of the expansion joint, a first sealing groove is arranged between the draft tube flange and the expansion joint, a first sealing ring is arranged in the first sealing groove, and the characteristics are: A second sealing groove is provided between the wheel chamber and the telescopic joint, and a second sealing ring is provided in the second sealing groove; a third sealing groove is formed at the contact position between the wheel chamber, the telescopic joint and the pressure plate, and the cross-section of the third sealing groove is a triangular structure, and three sealing rings are provided in the third sealing groove.

2. The sealing structure of the expansion joint of the runner chamber of a water turbine according to claim 1, characterized in that: The three sealing rings include a third sealing ring, a fourth sealing ring and a fifth sealing ring. The fourth sealing ring is arranged on the inner side of the third sealing ring, and the fifth sealing ring is arranged on the outer side of the third sealing ring.

3. The sealing structure of the expansion joint of the runner chamber of a water turbine according to claim 1, characterized in that: The first sealing ring is an O-shaped sealing ring, and the diameter of the O-shaped sealing ring is Φ9mm.

4. The sealing structure of the expansion joint of the runner chamber of a water turbine according to claim 1, characterized in that: The second sealing ring is an O-shaped sealing ring, and the diameter of the O-shaped sealing ring is Φ13 mm.

5. The sealing structure of the expansion joint of the runner chamber of a water turbine according to claim 2, characterized in that: The third sealing ring, the fourth sealing ring and the fifth sealing ring are all O-rings. The diameter of the third sealing ring is Φ18 mm, the diameter of the fourth sealing ring is Φ6 mm, and the diameter of the fifth sealing ring is Φ8 mm.

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