Fixing device for safety connecting rod of water guide mechanism of through-flow turbine

Abstract

The invention relates to the technical field of electric water turbines, in particular to a safety connecting rod fixing device for a water guide mechanism of a tubular turbine. A stop plate is connected to the center of an eccentric shaft of the safety connecting rod through a screw, and a cylindrical pin is arranged at the off-center position between contact surfaces of the stop plate and the eccentric shaft; an end cover is fixed on the safety connecting rod beside the eccentric shaft through a bolt, an inner cavity of the end cover covers the stop plate, and a sealing gasket is arranged between the end cover and the stop plate; the end cover is provided with a hole channel communicated with an inner cavity of the end cover, and a screw plug is screwed in the hole channel; and a pin shaft is screwed in the middle of the end cover. And the original end cover bolt is locked by additionally arranging the stop plate and the end cover. The device is simple, does not influence the normal action of the water guide mechanism, is easy to install, does not have welding or other processes which possibly deform the equipment, and is safe and reliable in operation. Cost is low and manufacturing is simple. And popularization to other units of the same type is easy.

Description

Technical Field

[0001] The invention relates to the technical field of electric water turbines, in particular to a safety connecting rod fixing device for a water guiding mechanism of a tubular water turbine. Background Art

[0002] In the prior art, the water guide mechanism of the bulb-type cross-flow turbine is the main equipment for starting and stopping the turbine, regulating the water inlet flow, and cutting off the water flow in case of accidents. Its equipment reliability and safety are particularly important. When the guide vane is closed for unit adjustment or shutdown, the guide vane may be stuck when closed due to foreign matter in the guide vane. Since the movable guide vanes of the turbine are all controlled by the control ring as a whole, when individual guide vanes are stuck, the control ring will not be able to operate, so that all movable guide vanes cannot be closed, resulting in the inability to shut down the unit, and there is a possibility of the accident expanding when the unit is shut down in an accident. In order to prevent such accidents from happening, the water guide mechanism of the turbine is currently equipped with a safety link. When the movable guide vane is stuck, the safety link will be activated to isolate the faulty guide vane from the control ring and restore the normal closing function of other movable guide vanes. The safety link itself is a protective device for the water turbine and reduces the workload of maintenance and treatment. It should reduce the daily workload. However, due to design defects, the safety links of most hydropower station bulb-type units are prone to the phenomenon of the safety links falling off as a whole, causing the unit to shut down unexpectedly, causing the ordinary connecting rod to break during the shutdown process, and causing varying degrees of damage to other surrounding linkage equipment. Figure 3 , the names of the parts are as follows: bolt 2, guide vane arm 6, eccentric shaft 9 safety link 10 joint bearing 12, second end cover 15, second screw 16, joint bearing pressure cover 17. Safety link 10 Figure 3 The safety link 10 is installed vertically. Since the safety link 10 is heavy and has outward gravity, the safety link 10, the second end cover 15, and the second screw 16 are combined together to form a whole. When the safety link 10 rotates, it is easy to cause the second screw 16 to loosen, causing a gap between the second end cover 15 and the eccentric pin. After the safety link 10 has been in operation for a long time, the second screw 16 and the second end cover 15 fall off, causing the safety link 5 to fall off the eccentric shaft 9, and the safety link 10 falls off as a whole, causing the unit to shut down unexpectedly. According to the on-site accident phenomenon and theoretical analysis, it was determined that the safety link fell off during long-term operation due to design defects. In order to prevent similar phenomena from occurring, the unit needs to be regularly stopped on site, and the bolts of the safety link need to be tightened one by one, which increases the workload of daily maintenance and reduces the power generation efficiency.

[0003] There is currently no specific solution to the problem of the safety link falling off in the water guide mechanism of the bulb tubular unit. At the same time, the spherical bearing at the installation position of the safety link fixture is a movable part, and its movement mode is three-dimensional operation, not plane movement, which increases the design difficulty of not affecting the normal movement of the safety link after the fixture is installed. Summary of the invention

[0004] The object of the present invention is to provide a safety connecting rod fixing device for a water guide mechanism of a tubular turbine which has a simple structure and is safe and reliable to use in view of the above-mentioned deficiencies.

[0005] The technical solution of the present invention is: a safety connecting rod fixing device for a water guide mechanism of a tubular turbine, wherein a stop plate is connected to the center of the eccentric shaft of the safety connecting rod by screws, and a cylindrical pin is provided at the eccentric center between the stop plate and the contact surface of the eccentric shaft; an end cover is fixed to the safety connecting rod beside the eccentric shaft by bolts, and the inner cavity of the end cover covers the stop plate and a D-type rubber seal is provided between the end cover; a hole is provided on the end cover that leads to the inner cavity of the end cover, and a screw plug is screwed into the hole; and a special pin is screwed in the middle of the end cover. The eccentric shaft can be a straight pin shaft.

[0006] The advantages of the present invention are: 1. The original water guide mechanism action design principle is not changed. By adding a new stop plate and an end cover to lock the original end cover bolt, it can ensure that the unit can limit and fix the safety connecting rod pin during long-term operation, and can effectively prevent the unit from shutting down due to the safety connecting rod falling off, breaking of the ordinary connecting rod, and damage to the linkage equipment. 2. The device is simple, does not affect the normal action of the water guide mechanism, is easy to install, does not involve welding or other processes that may cause deformation of the equipment, and is safe and reliable in operation. 3. Low cost and simple to manufacture. 4. Easy to promote to other units of the same type.

[0007] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a schematic diagram of the connection structure at the guide vane arm end of the safety link of the present invention.

[0009] Figure 2 It is a schematic diagram of the connection structure at the control ring end of the safety link of the present invention.

[0010] Figure 3 It is a schematic diagram of the safety link structure before improvement. DETAILED DESCRIPTION

[0011] See also Figure 1 , 2 ,The names of the parts are as follows: end cover 1, bolt 2, stop plate 3, D-type rubber seal 4, special pin 5, screw 6, screw plug 7, cylindrical pin 8, eccentric shaft 9, safety link 10, guide vane arm 11, spherical bearing 12, straight pin shaft 13, filling grease 14.

[0012] See also Figure 1 , 2A safety connecting rod fixing device for a water-guiding mechanism of a cross-flow turbine is provided. A stop plate 3 is connected to the center of the eccentric shaft 9 of the safety connecting rod by a screw 6. A cylindrical pin 8 is provided at the eccentric center between the contact surface of the stop plate 3 and the eccentric shaft 9. An end cover 1 is fixed to the safety connecting rod 10 next to the eccentric shaft 9 by four bolts 2. The inner cavity of the end cover 1 covers the stop plate 3 and there is a D-type rubber seal between them. The compressibility of the seal serves as the action space for the small angular displacement generated when the water-guiding structure is in motion. There is a hole on the end cover 1 that leads to the inner cavity of the end cover 1. The hole is used to fill grease. A screw plug 7 is screwed into the hole for sealing. There is a special pin 5 screwed in the middle of the end cover 1 for tightening the screw 6 to ensure that the stop plate 3 does not loosen.

[0013] The fixture is manufactured according to the design, and the eccentric shaft 9 is removed during the unit overhaul, and a hole is drilled in the eccentric shaft 9. The drilling position of the eccentric shaft 9 corresponds to the stop plate 3. After completing the preliminary production and preparation work, the installation is carried out in conjunction with the unit overhaul. Specific installation steps: 1. Install the eccentric shaft 9 with a hole. 2. Install the D-type rubber seal 4 on the stop plate 3. 3. Install the cylindrical pin 8 between the eccentric shaft 9 and the stop plate 3. 4. Install the stop plate 3 and tighten the M12 screw 6. 5. Remove the original joint bearing gland. 6. Install the newly designed joint bearing end cover 1 and tighten the four M8 bolts 2. 7. After injecting grease through the end cover 1 channel, screw in the screw plug 7. 8. Install the special pin 5, and tighten the screw 6 without removing the end cover 1 to ensure that the stop plate 3 does not loosen. After all the installations, the overall operation is good, the bolts of each part are tightly connected, and the water guide mechanism works well, which completely solves the problem that the fixture cannot rotate. The eccentric shaft 9 is connected to the stop plate 3 by a cylindrical pin 8, and the stop plate 3 is then fixed by the end cover 1. A D-type rubber seal 4 is added between the stop plate 3 and the end cover 1. The compressibility of the seal serves as the action space for the small angular displacement generated when the water guide structure moves.

[0014] See also Figure 1 , 2 , Figure 1 , Figure 2 The two figures are structural diagrams of the redesigned fixing devices at both ends of the safety link. Figure 1 This device is installed on the guide vane arm of the water guide mechanism. Figure 2 This device is installed on the water guide mechanism control ring, and the guide vane arm 11 side is the eccentric shaft 9. Figure 2 The control ring side is a straight pin shaft 13, and the other parts are the same.

[0015] The above description is only a specific implementation mode of the present invention, and various examples do not constitute a limitation on the essential content of the present invention.

Claims

1. A safety connecting rod fixing device for a tubular turbine water guide mechanism, characterized in that A stop plate (3) is connected to the center of the eccentric shaft (9) of the safety link (10) by means of a screw (6), and a cylindrical pin (8) is provided at the eccentric center between the contact surface of the stop plate (3) and the eccentric shaft (9); an end cover (1) is fixed to the safety link (10) beside the eccentric shaft (9) by means of a bolt (2), and the inner cavity of the end cover (1) covers the stop plate (3) and a D-type rubber seal (4) is provided between the end cover (1); a hole is provided on the end cover (1) that leads into the inner cavity of the end cover (1), and a screw plug (7) is screwed into the hole; and a special pin (5) is screwed into the middle of the end cover (1).

2. A safety connecting rod fixing device for a tubular turbine water guide mechanism according to claim 1, characterized in that The eccentric shaft (9) may be a straight pin shaft (13).

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