Vertical hydro-generator air gap inspection tool

Abstract

An air gap inspection tool for a vertical hydro-generator comprises an arm ring, an insulating rope, a holding part and a counterweight, one end of the insulating rope is connected with the arm ring, the other end of the insulating rope is connected with the counterweight, the holding part is mounted on the insulating rope and close to one end of the arm ring, and the counterweight is made of a non-magnetic material. By means of the structure, the risks that the connecting part of the inspection tool is broken, part of materials are adsorbed or clamped in the generator and the tool falls off in the using process are avoided, and the action burden of workers is relieved.

Description

Technical Field

[0001] The utility model relates to the technical field of maintenance tools for vertical hydro-generators, and particularly to an air-gap inspection tool for vertical hydro-generators. Background Art

[0002] When overhauling a vertical hydro-generator with a rated power greater than 150 MW and above, it is necessary to focus on inspecting the air gap between the stator and rotor of the generator. The air gap of a vertical hydro-generator is very small, and the length of the stator core is relatively long. Taking the parameters of a domestic 150 MW vertical hydro-turbine as an example, the length of the stator core reaches 1590 mm, and the air gap is only 20 mm.

[0003] When conducting an air-gap inspection, one of the items is to check for debris in the air gap between the stator and rotor of the generator. Previously, the method of tying a bolt with a white cotton cloth tape was usually used as a tool for inspecting the gap. Its disadvantages are as follows:

[0004] Firstly: After the hydro-generator stops running, there will inevitably be residual magnetism. During the process of lowering and removing the metal bolt, it is extremely easy to be adsorbed on the surface of the magnetic pole or iron core. Since there are many uneven surfaces inside the air gap, when the bolt is adsorbed, it is extremely difficult to pull it out only by the white cotton cloth tape. In severe cases, it will get stuck in the gap and cannot be taken out. It is absolutely not allowed to leave metal materials inside the generator, as it will cause serious harm during operation. Therefore, the magnetic adsorption of the metal bolt in the inspection tool and its own uneven surface are serious defects affecting the operation of the equipment.

[0005] Secondly: The strength of an ordinary white cotton cloth tape is insufficient. During the inspection along the outer edge of the magnetic pole, if it is caught by protrusions such as the magnetic pole connection plate, it is not easy to pull out. In severe cases, the white cloth tape will be torn and left in the air gap, affecting the safe operation of the generator.

[0006] Thirdly: When inspecting the air gap, the upper staff holds the inspection tool by tightly grasping the upper end of the white cotton cloth tape. Since the inspection tool has no anti-falling function, if it accidentally breaks away from the hand, it will directly fall inside the generator. Therefore, the staff's hand holding the inspection tool must always be kept in a tightly grasped state, adding burden and risk to the operation in the narrow space inside the generator. Content of the Utility Model

[0007] The technical problem to be solved by the utility model is to solve the problems existing in the above background art, provide an air-gap inspection tool for vertical hydro-generators, avoid the risk of breakage of the connection part of the inspection tool, adsorption or jamming of some materials inside the generator, and falling of the tool during use, and reduce the operation burden for the staff.

[0008] In order to achieve the above technical features, the purpose of the present utility model is realized as follows: A vertical hydrogenerator air gap inspection tool, comprising an arm ring, an insulating rope, a holding part, and a counterweight. One end of the insulating rope is connected to the arm ring, and the other end is connected to the counterweight. The holding part is installed on the insulating rope and close to one end of the arm ring. The counterweight is made of non-magnetic material.

[0009] The arm ring is made of aramid cloth tape, and both ends of the aramid cloth tape are provided with Velcro that can be adhered.

[0010] An insertion hole is axially provided inside the holding part, and the insulating rope passes through the insertion hole. A limit screw is rotatably installed on one side of the holding part, and the limit screw abuts against the insulating rope to limit and fix the holding part.

[0011] A holding ring is further provided on the outer wall of the holding part.

[0012] A through hole is provided at the center of the counterweight, and the insulating rope passes through the through hole. Limit members are fixed on the insulating rope at both ends of the counterweight.

[0013] The counterweight includes a hanging part and a bottom cover. The hanging part is provided with a connection hole. After the insulating rope passes through the connection hole of the hanging part, a limit member is fixed at the end of the insulating rope. The lower end of the hanging part is provided with internal threads, and the upper end of the bottom cover is provided with external threads. The bottom cover is screwed and fixed with the hanging part.

[0014] The present utility model has the following beneficial effects:

[0015] 1. The inspection tool is sleeved on the arm through the arm ring, the insulating rope is held through the holding part, the counterweight is used to pass through the air gap between the generator stator and rotor, and the insulating rope between the holding part and the counterweight is used to check for debris in the air gap. The arm ring can prevent the inspection tool from falling, the holding part is convenient for the hand to hold easily, the insulating rope is made of high-strength synthetic fiber insulating rope, and the counterweight is made of non-magnetic material and will not be adsorbed on the surface of the magnetic pole or iron core. Through the above structure, the risks of the connection part of the inspection tool breaking, some materials being adsorbed or stuck inside the generator, and the tool falling during use are avoided, and the action burden of the staff is reduced.

[0016] 2. A holding ring is further provided on the outer wall of the holding part, which is convenient for the hand to hold and not easy to slip, further reducing the action burden of the staff.

[0017] 3. The counterweight includes a hanging part and a bottom cover. The hanging part is provided with a connection hole. After the insulating rope passes through the connection hole of the hanging part, a limit member is fixed at the end of the insulating rope. The bottom cover is screwed and fixed with the hanging part. Even if the counterweight falls off, the limit member will be retained inside the counterweight, making it easy to find. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of the present utility model.

[0019] Figure 2 This is a schematic diagram of the counterweight structure of the present utility model.

[0020] In the figure:

[0021] Arm ring 1, Velcro 11, insulating rope 2, limiting member 21, holding part 3, insertion hole 31, limiting screw 32, counterweight 4, drooping part 41, bottom cover 42, connection hole 43, internal thread 44. Specific embodiments

[0022] The following further describes the embodiments of the present utility model with reference to the accompanying drawings.

[0023] Refer to Figure 1-2 , a vertical hydrogenerator air gap inspection tool, including an arm ring 1, an insulating rope 2, a holding part 3 and a counterweight 4. One end of the insulating rope 2 is connected to the arm ring 1, and the other end is connected to the counterweight 4. The holding part 3 is installed on the insulating rope 2 and close to one end of the arm ring 1. The counterweight 4 is made of non-magnetic material. The inspection tool is sleeved on the arm through the arm ring 1, the insulating rope 2 is held through the holding part 3, the counterweight 4 is used to pass through the air gap between the generator stator and rotor, and the insulating rope 2 between the holding part 3 and the counterweight 4 is used to check for debris in the air gap. The arm ring 1 can prevent the inspection tool from falling, the holding part 3 is convenient for the hand to hold easily, the insulating rope 2 is made of high-strength synthetic fiber insulating rope, the counterweight 4 is made of non-magnetic material and will not be adsorbed on the surface of the magnetic pole or iron core. Through the above structure, the risks of breakage of the connection part of the inspection tool, adsorption or jamming of some materials inside the generator and falling of the tool during use are avoided, and the action burden of the staff is reduced.

[0024] The counterweight 4 can be a spherical or capsule structure, and the material is preferably rubber or nylon.

[0025] Specifically, the arm ring 1 is an aramid cloth belt, and Velcro 11 that can be adhered is provided at both ends of the aramid cloth belt. In this way, the arm ring 1 can be firmly tied to the arm.

[0026] The arm ring 1 is woven from aramid fiber, and Velcro is respectively pasted on the side surfaces at both ends along the same direction, and the two sides of the Velcro can be firmly attached to each other. There are two holes in the middle of the arm ring 1, and the insulating rope 2 enters from one hole and exits from the other hole from below, and the exiting part is tied and fixed to the insulating rope 2 below the arm ring 1 with a cable tie, so as to realize the firm connection between the arm ring 1 and the insulating rope 2.

[0027] Specifically, refer to Figure 1, a penetration hole 31 is axially provided in the holding part 3, the insulating rope 2 passes through the penetration hole 31, a limit screw 32 is rotatably connected and installed on one side of the holding part 3, and the limit screw 32 abuts against the insulating rope 2 to limit and fix the holding part 3. Through the above structure, the connection and fixation between the holding part 3 and the insulating rope 2 are realized. In addition to the above method, the holding part 3 can also be a structure integrated with the insulating rope 2, or the holding part 3 is a structure that clamps the insulating rope 2 through two parts.

[0028] Furthermore, a holding ring 33 is also provided on the outer wall of the holding part 3. It is convenient for hand holding and not easy to slip, further reducing the action burden of the staff.

[0029] See Figure 1 , a through hole is provided at the center of the counterweight 4, the insulating rope 2 passes through the through hole, and limit members 21 are fixed on the insulating ropes 2 at both ends of the counterweight 4. The counterweight 4 is fixed by the limit members 21 at both ends, and the structure is simple.

[0030] Preferably, the limit member 21 can be a cable tie or an aluminum rope buckle.

[0031] Since the limit members 21 are fixed on the insulating ropes 2 at both ends of the counterweight 4, if the counterweight 4 falls off, the counterweight 4 and the lower limit member 21 will fall off separately. The counterweight 4 is relatively large and easy to find, while the limit member 21 is relatively small and not easy to find.

[0032] Therefore, in another solution, see Figure 2 , the counterweight 4 includes a hanging part 41 and a bottom cover 42. The hanging part 41 is provided with a connection hole 43. After the insulating rope 2 passes through the connection hole 43 of the hanging part 41, a limit member 21 is fixed at the end of the insulating rope 2. An internal thread 44 is provided at the lower end of the hanging part 41, and an external thread is provided at the upper end of the bottom cover 42. The bottom cover 42 is threadedly connected and fixed to the hanging part 41. Through the above structure, even if the counterweight 4 falls off, the limit member 21 will be retained inside the counterweight 4, making it easy to find.

[0033] The working principle or process of the present utility model:

[0034] When performing the air gap inspection, the staff stands at the upper end of the stator bar. First, tie the arm ring 1 to the wrist. Hold the holding part 3 with one hand, and lower the counterweight 4 from the air gap to the lower end of the stator bar with the other hand. Then check around the outer edge of the rotor for one week to complete the air gap inspection work of the hydrogenerator stator and rotor.

Claims

1. A vertical hydro-generator air gap inspection tool, characterized in that: An armband (1), an insulating rope (2), a gripping portion (3) and a counterweight (4), wherein one end of the insulating rope (2) is connected to the armband (1), and the other end is connected to the counterweight (4), the gripping portion (3) is mounted on the insulating rope (2) and is close to one end of the armband (1), and the counterweight (4) is made of a non-magnetic material.

2. A vertical hydro-generator air gap inspection tool according to claim 1, characterized in that: The armband (1) is an aramid cloth belt, and both ends of the aramid cloth belt are provided with Velcro (11) capable of bonding.

3. A vertical hydro-generator air gap inspection tool according to claim 1, characterized in that: An insertion hole (31) is axially provided in the holding portion (3), and the insulating rope (2) passes through the insertion hole (31). A limit screw (32) is screwed and installed on one side of the holding portion (3), and the limit screw (32) abuts against the insulating rope (2) to limit and fix the holding portion (3).

4. A vertical hydro-generator air gap inspection tool according to claim 1 or 3, characterized in that: The outer wall of the gripping portion (3) is also provided with a gripping ring (33).

5. A vertical hydro-generator air gap inspection tool according to claim 1, characterized in that: A through hole is provided at the center of the counterweight (4), and the insulating rope (2) passes through the through hole. Limiting pieces (21) are fixedly provided on the insulating ropes (2) at both ends of the counterweight (4).

6. A vertical hydro-generator air gap inspection tool according to claim 1, characterized in that: The counterweight (4) comprises a drooping portion (41) and a bottom cover (42); the drooping portion (41) is provided with a connection hole (43); after the insulating rope (2) passes through the connection hole (43) of the drooping portion (41), a stopper (21) is fixedly provided at the end of the insulating rope (2); the lower end of the drooping portion (41) is provided with an internal thread (44); the upper end of the bottom cover (42) is provided with an external thread; the bottom cover (42) and the drooping portion (41) are screwed and fixed.

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