A nuclear power plant steam turbine turning system

Abstract

The present invention relates to the technical field of large-scale electromechanical equipment maintenance, and specifically discloses a nuclear power plant turbine cranking system for cranking a ratchet wheel attached to a turbine rotor, comprising a control system and a ratchet driving device; the ratchet driving device comprises a fixed base, a telescopic mechanism, and a tooth pusher engaged with the ratchet wheel; the fixed end of the telescopic mechanism is rotatably connected to the fixed base and can perform a first rotation, and the telescopic end of the telescopic mechanism is rotatably connected to the tooth pusher and can perform a second rotation; the fixed base is fixed to the side of the ratchet wheel, and the tooth pusher is arranged facing the circumferential gear surface of the ratchet wheel; the tooth pusher engages with at least one tooth of the ratchet wheel; the telescopic mechanism reciprocates and retracts under the control of the control system to drive the tooth pusher to repeatedly engage with the ratchet wheel, thereby continuously driving the ratchet wheel to rotate. The device of the present invention is ingeniously designed and has good stability.

Description

Technical Field

[0001] The invention belongs to the technical field of large-scale electromechanical equipment maintenance, and in particular relates to a nuclear power plant steam turbine turning system. Background Art

[0002] To prevent the rotor shaft from bending during emergency shutdown or maintenance, large generator sets require an external force to slowly rotate the rotor shaft until it comes to a complete stop. Generator sets are equipped with a cranking device that allows the rotor to rotate slowly, but it can only be used during normal startup or shutdown conditions. It cannot be used during emergency shutdown or maintenance.

[0003] To address this issue, some external turning gears are available that can be installed during emergency shutdowns or maintenance. However, these gear-driven turning gears utilize electric motors or hydraulic power to drive the turning gears on the rotor shaft. Because the gear teeth on the rotor shaft are all one-way ratchet-type, rather than the modular tooth profile of a gear drive, these external gear-driven turning gears can cause significant damage to the rotor shaft during use, severely reducing the rotor shaft's service life. Furthermore, these turning gears are bulky and inconvenient to install and use.

[0004] Therefore, it is urgent to design a nuclear power plant turbine turning system to solve the above problems. Summary of the Invention

[0005] The object of the present invention is to provide a nuclear power plant steam turbine cranking system which can continuously push the ratchet without damaging the cranking gear.

[0006] The technical solutions of the present invention are as follows:

[0007] A nuclear power plant steam turbine cranking system is used to crank the ratchet of the steam turbine rotor, including a control system and a ratchet driving device;

[0008] The ratchet pushing device includes a fixed base, a telescopic mechanism, and a pushing tooth head engaged with the ratchet;

[0009] The fixed end of the telescopic mechanism is rotatably connected to the fixed base and can perform a first rotation, and the telescopic end of the telescopic mechanism is rotatably connected to the tooth-pushing head and can perform a second rotation;

[0010] The fixed base is fixed to the side of the ratchet, and the tooth pusher is arranged facing the circumferential gear surface of the ratchet;

[0011] The push tooth head is engaged with at least one tooth of the ratchet;

[0012] The telescopic mechanism reciprocates and contracts under the control of the control system to drive the tooth pushing head to engage with the ratchet wheel repeatedly, thereby continuously pushing the ratchet wheel to rotate.

[0013] Also includes a rotating seat and a guide rod;

[0014] The rotating seat is rotatably connected to the fixed base and can perform a third rotation; the guide rod is movably arranged in the rotating seat, and the top of the guide rod is rotatably connected to the telescopic mechanism and can perform a fourth rotation;

[0015] The guide rod, telescopic mechanism and fixed base are combined to form a triangular structure to improve the stability of the entire turning system.

[0016] The push gear head includes a connecting plate and two connecting columns perpendicular to the connecting plate;

[0017] The two connecting posts are connected to the top and bottom ends of the connecting plate respectively, and the side walls of the two connecting posts and the connecting plate facing the circumferential gear surface of the ratchet are exactly engaged with the teeth of the ratchet;

[0018] The connecting plate is located between the two connecting columns and is rotatably connected to the telescopic end of the telescopic mechanism.

[0019] The fixed base includes a set of first fixing ears;

[0020] The set of first fixing ears is used to be hinged to the telescopic mechanism to achieve a first rotation.

[0021] The fixed base includes a set of second fixing ears;

[0022] The set of second fixing ears is used for being hinged to the rotating seat to realize the third rotation.

[0023] The telescopic end of the telescopic mechanism is connected to a connecting piece, and an end of the connecting piece away from the telescopic end forms a set of third fixing ears;

[0024] The set of third fixing ears is used for being hinged to the pushing gear head to realize the second rotation.

[0025] The telescopic end of the telescopic mechanism is connected to a connecting piece, and a group of fourth fixing ears are formed at the bottom of the connecting piece near the telescopic end;

[0026] The top of the guide rod is connected to a pair of connecting shafts perpendicular to the guide rod, and the set of fourth fixing ears is used to be hinged to the pair of connecting shafts at the top of the guide rod to achieve the fourth rotation.

[0027] The rotating seat includes a square flange linear bearing and a bearing seat;

[0028] The bearing seat includes a square main body and two cylindrical parts respectively connected to two pairs of side walls of the square main body. The square main body has a central hole, and the two cylindrical parts are hinged to the fixed base.

[0029] The linear bearing is inserted into the bearing seat, and the guide rod passes through the linear bearing.

[0030] The control system includes a manual pump, a pressure gauge used to monitor the pressure of the manual pump in conjunction with the manual pump, an electric pump, a pressure sensor used to monitor the pressure of the electric pump in conjunction with the electric pump, and a switching valve;

[0031] The manual pump and the electric pump are connected to the telescopic mechanism via a switching valve respectively. The switching valve is used to select one of the manual pump and the electric pump to drive the telescopic mechanism.

[0032] It also includes a mobile cart, and the control system is arranged on the mobile cart to facilitate the movement of the entire system.

[0033] The remarkable effects of the present invention are:

[0034] (1) The present invention utilizes the telescopic mechanism to reciprocate and retract to drive the push gear head to repeatedly engage with the ratchet wheel, thereby continuously pushing the ratchet wheel to rotate, and can achieve continuous pushing of the ratchet wheel while minimizing damage to the winch gear.

[0035] (2) The device of the present invention is quick to install. It only needs to fix the fixed base to the side of the ratchet and set the push gear head to face the circumferential gear surface of the ratchet. By adjusting the distance, the push gear head can be driven to repeatedly engage with the ratchet when the telescopic mechanism reciprocates and extends. The entire installation process is very convenient.

[0036] (3) The device of the present invention is cleverly designed, has good stability and low maintenance cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a schematic diagram of the installation of the turning system of the present invention;

[0038] Figure 2 1. It is a schematic diagram of the structure of the ratchet pushing device;

[0039] Figure 3 This is an exploded view of the ratchet pusher.

[0040] In the figure, 1-ratchet; 2-fixed base; 3-telescopic mechanism; 4-push gear head; 5-rotating seat; 6-guide rod; 21-first fixing ear; 22-second fixing ear; 31-connecting piece; 41-connecting plate; 42-connecting column; 51-bearing seat; 52-square flange linear bearing; 100-ratchet pushing device; 311-third fixing ear; 312 fourth fixing ear. DETAILED DESCRIPTION

[0041] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The drawings illustrate exemplary embodiments of the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present invention.

[0042] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element that improves the connection relationship. The terms "vertical," "horizontal," "front," "rear," and similar expressions used herein are for illustrative purposes only.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0044] Terms containing ordinal numbers, such as "first" and "second," used in this specification may be used to describe various components, but these components are not limited by these terms. These terms are used solely to distinguish one component from another. For example, a first component may be named a second component, and similarly, a second component may be named a first component, without departing from the scope of the present invention.

[0045] like Figure 1 The steam turbine cranking system of a nuclear power plant shown is used to crank the ratchet 1 provided on the steam turbine rotor, and includes a control system and a ratchet driving device 100 .

[0046] like Figure 2 As shown, the ratchet pushing device 100 includes a fixed base 2, a telescopic mechanism 3 and a tooth-pushing head 4 that can engage with the ratchet 1. The main body materials of the fixed base 2 and the tooth-pushing head 4 are both steel.

[0047] The fixed end of the telescopic mechanism 3 is rotatably connected to the fixed base 2 and is capable of a first rotation. The telescopic end of the telescopic mechanism 3 is rotatably connected to the tooth pusher 4 and is capable of a second rotation. The rotational axis of the first and second rotations is parallel to the rotational axis of the ratchet 1. It should be noted that the rotational axis mentioned herein is a virtual axis, not a physical axis. It mainly refers to the rotation relative to the rotational axis.

[0048] The fixed base 2 is fixed to the side of the ratchet 1, and the tooth pusher 4 is arranged facing the circumferential gear surface of the ratchet 1. The telescopic mechanism 3 reciprocates and retracts under the control of the control system to drive the tooth pusher 4 to repeatedly engage with the ratchet 1, thereby continuously driving the ratchet 1 to rotate.

[0049] In this embodiment, specifically, the telescopic mechanism 3 comprises a reciprocating oil cylinder. It is understandable that in other embodiments, the telescopic mechanism 3 is not limited to an oil cylinder, and any device capable of achieving reciprocating linear motion may be used, such as a pneumatic cylinder or an electric cylinder.

[0050] In theory, the push gear head 4 is engaged with at least one tooth of the ratchet 1. In this embodiment, specifically, refer to Figure 3 , the push tooth head 4 includes a connecting plate 41 and two connecting columns 42 perpendicular to the connecting plate 41. The two connecting columns 42 are respectively connected to the top and bottom ends of the connecting plate 41, and the two connecting columns 42 and the side walls of the connecting plate 41 facing the circumferential gear surface of the ratchet 1 are just engaged with the three teeth of the ratchet 1. Of course, in other embodiments, there can also be two teeth or more than three teeth. The connecting plate 41 is located between the two connecting columns 42 and is rotatably connected to the telescopic end of the telescopic mechanism 3. Specifically, the connecting plate 41 is a trapezoidal plate that stands upright at an angle, and the bottom edge of the trapezoidal plate is the side wall facing the circumferential gear surface of the ratchet 1, and the two bottom corners of the trapezoidal plate are connected to the top and bottom ends of the two connecting columns 42.

[0051] Preferably, in this embodiment, the device further comprises a rotating seat 5 and a guide rod 6. The rotating seat 5 is rotatably connected to the fixed base 2 and can perform a third rotation. The guide rod 6 is movably arranged in the rotating seat 5, and the top of the guide rod 6 is rotatably connected to the telescopic mechanism 3 and can perform a fourth rotation. The rotation center axis of the third and fourth rotations is parallel to the rotation center axis of the ratchet 1. Figure 2 The arrows in the figure indicate the rotation direction of the ratchet 1 and the rotation directions of the first, second, third and fourth rotations.

[0052] like Figure 2 In the figure, the guide rod 6, the telescopic mechanism 3 and the fixed base 2 form an obtuse triangle, an obtuse angle is formed at the connection position between the guide rod 6 and the fixed base 2, an acute angle is formed between the guide rod 6 and the telescopic mechanism 3, and an acute angle is formed at the connection position between the telescopic mechanism 3 and the fixed base 2, which can improve the stability of the entire device.

[0053] Specifically, the fixed base 2 includes a set of first fixing ears 21 and a set of second fixing ears 22. The set of first fixing ears 21 is used to be hinged with the telescopic mechanism 3 to achieve the first rotation, and the set of second fixing ears 22 is used to be hinged with the rotating base 5 to achieve the third rotation. The set of second fixing ears 22 is closer to the ratchet 1 than the set of first fixing ears 21. Figures 2-3In the embodiment, a group of second fixing ears 22 is located below and in front of a group of first fixing ears 21 and is closer to the ratchet 1 .

[0054] Specifically, the telescopic end of the telescopic mechanism 3 is connected to a connecting piece 31, and the end of the connecting piece 31 away from the telescopic end forms a group of third fixing ears 311, and the bottom of the connecting piece 31 near the telescopic end forms a group of fourth fixing ears 312. Figure 3 In the embodiment, the third fixing lugs 311 and the fourth fixing lugs 312 are arranged approximately perpendicularly, with the third fixing lugs 311 facing forward and the fourth fixing lugs 312 facing downward. The set of third fixing lugs 311 are hingedly connected to the connecting plate 41 of the pusher head 4 to achieve the second rotation. The top of the guide rod 6 is connected to a pair of connecting shafts perpendicular to the guide rod 6, and the set of fourth fixing lugs 312 are hingedly connected to the pair of connecting shafts at the top of the guide rod 6 to achieve the fourth rotation.

[0055] Specifically, the rotating seat 5 includes a square flange linear bearing 52 and a bearing seat 51. The bearing seat 51 includes a square main body and two cylindrical parts respectively connected to the two pairs of side walls of the square main body. The square main body is provided with a center hole. The two cylindrical parts and the second fixed ear 22 realize the hinge connection between the bearing seat 51 and the fixed base 2. The linear bearing 52 is inserted into the bearing seat 51. Specifically, the cylindrical bearing part of the linear bearing 52 is inserted into the center hole of the square main body of the bearing seat 51. The square flange of the linear bearing 52 is stacked with the square main body of the bearing seat 51 and is locked by four screws or other connecting parts located at the four corners. The guide rod 6 passes through the linear bearing 52. Of course, the linear bearing 52 and the bearing seat 51 are only a preferred embodiment of the rotating seat 5 in this embodiment. In fact, the rotating seat 5 can be a rotatable guide sleeve, and the guide rod 6 directly passes through the guide sleeve.

[0056] It can be understood that the specific structure of the tooth-pushing head 4 described in this embodiment is a preferred structure, and the rotating seat 5, guide rod 6, etc. are auxiliary structures, and their main function is to push the tooth-pushing head 4.

[0057] In other embodiments, the tooth-pushing head 4 can be simpler, for example, simply meshing with one tooth of the ratchet 1. In short, as long as the tooth-pushing head 4 can mesh with the ratchet 1 and drive it to rotate, auxiliary structures such as the rotating base 5 and the guide rod 6 can also be omitted.

[0058] The control system described in this embodiment preferably includes a manual pump, a pressure gauge that cooperates with the manual pump to monitor the manual pump's pressure, an electric pump, a pressure sensor that cooperates with the electric pump to monitor the electric pump's pressure, and a switching valve. The manual pump and electric pump are each connected to the telescopic mechanism 3 via a switching valve. The switching valve is used to select either the manual pump or the electric pump to drive the telescopic mechanism 3. The manual pump is intended for use in emergency situations where power is unavailable. The switching valve has three positions: switching to the middle position enables electric control, switching to the left extends the telescopic mechanism 3, and switching to the right retracts the telescopic mechanism 3.

[0059] Preferably, the turning system may further include a mobile trolley, and the control system is arranged on the mobile trolley, so as to facilitate the movement of the entire system.

[0060] In summary, the nuclear power plant turbine winching system of the present invention has the following beneficial effects: since the fixed end of the telescopic mechanism is rotatably connected to the fixed base, and the telescopic end of the telescopic mechanism is rotatably connected to the push gear head, the telescopic mechanism is reciprocated to drive the push gear head to repeatedly engage with the ratchet, thereby continuously pushing the ratchet to rotate; the entire device can be installed quickly, and it is only necessary to fix the fixed base to the side of the ratchet, and set the push gear head facing the circumferential gear surface of the ratchet. By adjusting the distance, the push gear head can be driven to repeatedly engage with the ratchet when the telescopic mechanism reciprocates and extends. The entire installation process is very convenient.

[0061] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are protected by the present invention.

Claims

1. A nuclear power plant steam turbine turning system, characterized by: A ratchet (1) for turning a steam turbine rotor, comprising a control system and a ratchet pushing device (100); The ratchet pushing device (100) comprises a fixed base (2), a telescopic mechanism (3), and a tooth pushing head (4) engaged with the ratchet (1); The fixed end of the telescopic mechanism (3) is rotatably connected to the fixed base (2) and can perform a first rotation, and the telescopic end of the telescopic mechanism (3) is rotatably connected to the tooth-pushing head (4) and can perform a second rotation; The fixed base (2) is fixed to the side of the ratchet (1), and the tooth pusher (4) is arranged facing the circumferential gear surface of the ratchet (1); The tooth pusher (4) is engaged with at least one tooth of the ratchet (1); The telescopic mechanism (3) reciprocates and retracts under the control of the control system to drive the tooth pusher (4) to repeatedly engage with the ratchet (1), thereby continuously pushing the ratchet (1) to rotate; It also includes a rotating seat (5) and a guide rod (6); The rotating seat (5) is rotatably connected to the fixed base (2) and can perform a third rotation; the guide rod (6) is movably arranged in the rotating seat (5), and the top of the guide rod (6) is rotatably connected to the telescopic mechanism (3) and can perform a fourth rotation; The guide rod (6), the telescopic mechanism (3) and the fixed base (2) are enclosed to form a triangular structure to improve the stability of the entire turning system; The tooth pushing head (4) comprises a connecting plate (41) and two connecting columns (42) perpendicular to the connecting plate (41); The two connecting columns (42) are respectively connected to the top and bottom ends of the connecting plate (41), and the side walls of the two connecting columns (42) and the connecting plate (41) facing the circumferential gear surface of the ratchet (1) are exactly engaged with the teeth of the ratchet (1); The connecting plate (41) is located between the two connecting columns (42) and is rotatably connected to the telescopic end of the telescopic mechanism (3).

2. A nuclear power plant steam turbine turning system according to claim 1, characterized in that: The fixed base (2) includes a set of first fixing ears (21); The set of first fixing ears (21) is used to be hinged to the telescopic mechanism (3) to achieve a first rotation.

3. The nuclear power plant steam turbine turning system according to claim 1, characterized in that: The fixed base (2) includes a set of second fixing ears (22); The set of second fixing ears (22) is used to be hinged to the rotating seat (5) to achieve a third rotation.

4. The nuclear power plant steam turbine turning system according to claim 1, characterized in that: The telescopic end of the telescopic mechanism (3) is connected to a connecting piece (31), and an end of the connecting piece (31) away from the telescopic end forms a group of third fixing ears (311); The set of third fixing ears (311) is used for being hinged to the tooth pushing head (4) to achieve a second rotation.

5. The nuclear power plant steam turbine turning system according to claim 1, characterized in that: The telescopic end of the telescopic mechanism (3) is connected to a connecting piece (31), and a group of fourth fixing ears (312) are formed at the bottom of the connecting piece (31) near the telescopic end; The top of the guide rod (6) is connected to a pair of connecting shafts perpendicular to the guide rod (6), and the set of fourth fixing ears (312) is used to be hinged to the pair of connecting shafts at the top of the guide rod (6) to achieve a fourth rotation.

6. The nuclear power plant steam turbine turning system according to claim 1, characterized in that: The rotating seat (5) includes a square flange linear bearing (52) and a bearing seat (51); The bearing seat (51) comprises a square main body and two columnar parts respectively connected to two pairs of side walls of the square main body, the square main body is provided with a central hole, and the two columnar parts are hinged to the fixed base (2); The square flange linear bearing (52) is inserted into the bearing seat (51), and the guide rod (6) passes through the square flange linear bearing (52).

7. The nuclear power plant steam turbine turning system according to claim 1, characterized in that: The control system includes a manual pump, a pressure gauge used to monitor the pressure of the manual pump in conjunction with the manual pump, an electric pump, a pressure sensor used to monitor the pressure of the electric pump in conjunction with the electric pump, and a switching valve; The manual pump and the electric pump are respectively connected to the telescopic mechanism (3) via a switching valve, and the switching valve is used to select one of the manual pump and the electric pump to drive the telescopic mechanism (3).

8. The nuclear power plant steam turbine turning system according to claim 1, characterized in that: It also includes a mobile cart, and the control system is arranged on the mobile cart to facilitate the movement of the entire system.

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