JP2020112141A - Bearing cleaning method - Google Patents

Abstract

To efficiently wash away grease which is used in a pitch bearing or a yaw bearing of a windmill.SOLUTION: In a bearing cleaning method, a grease lubrication-type bearing for use in a windmill, and having an inner ring and an outer ring which can relatively turn with respect to each other is set as an object. In the method, a receiving member is arranged so as to oppose a discharge part arranged below the bearing from a lower side in a state that a vertical face becomes substantially horizontal. Then, grease is softened by making the inner ring and the outer ring relatively turn after supplying a cleaner to a supply part arranged at an upper part of the bearing, and a mixture of the grease discharged from the discharge part and the cleaner is collected by the receiving member.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to a bearing cleaning method for cleaning a grease lubricated bearing.

Windmills installed on land or at sea are known. This type of wind turbine is used, for example, as a wind turbine generator which is a kind of renewable energy generator. In a wind turbine generator, a rotor provided with a wind turbine blade is rotated by wind energy, and a generator connected to the rotor via a rotation shaft (main shaft) is driven to generate electric energy.

In wind turbines, grease-lubricated bearings that use grease as a lubricant are used to ensure good reliability under various operating conditions. For example, a wind turbine blade for receiving wind is attached to a rotor body (hub) via a pitch bearing so that wind energy received by the wind turbine blade can be adjusted. Further, the rotor of the wind turbine is attached to a tower standing on land or on the sea via a yaw bearing, so that the rotor can rotate so as to follow the wind direction.

Grease lubricants are used in such pitch bearings and yaw bearings, but since dirt components such as metal abrasion powder generated by the operation of a wind turbine increase, grease replenishment or replacement work at a predetermined cycle is required. Needs maintenance. Here, when the grease is replenished or replaced with respect to the bearing, it is preferable to discharge the existing grease containing the dirt component in advance and then replenish the new grease. Therefore, at the time of maintenance, a cleaning operation is required to discharge the used grease from the bearing.

Patent Documents 1 and 2 relate to a main shaft bearing for rotatably supporting a main shaft of a wind turbine, not the pitch bearing or the yaw bearing as described above, but an example of a method for cleaning a grease lubrication type bearing. Is disclosed. In these documents, the housing of the bearing is partially removed, and the grease inside the bearing is roughly manually removed. After that, with the cleaning cover attached to the bearing, the grease is discharged by performing spray cleaning through a hole provided in the cleaning cover. It is said that such spray cleaning needs to be performed for about 3 minutes for each hole provided in the cleaning cover.

European Patent Publication No. 2937564 US Patent Publication No. 2015/377294

In Patent Document 1 and Patent Document 2 described above, the main shaft bearing that rotatably supports the main shaft that extends along the substantially horizontal direction is targeted for cleaning, and the cleaning agent supplied from the upper part of the main shaft bearing together with grease forms the lower part of the bearing. Is discharged from. As described above, the techniques of Patent Document 1 and Patent Document 2 are based on the premise of a bearing that supports a rotating shaft extending along a substantially horizontal direction, and thus can be applied to pitch bearings and yaw bearings of wind turbines. Can not.

Moreover, in the said patent document 1 and the patent document 2, it is necessary to perform the grease removal by manual operation before implementing a spray washing operation. Further, also in the spray cleaning work, it is necessary to perform the spraying work for a long time for each hole provided in the cleaning cover. Therefore, the time and work load required for grease cleaning are large.

At least one embodiment of the present invention has been made in view of the above circumstances, and an object thereof is to provide a bearing cleaning method capable of efficiently cleaning grease used for a pitch bearing or a yaw bearing of a wind turbine.

(1) In order to solve the above problems, a bearing cleaning method according to at least one embodiment of the present invention,
A bearing cleaning method for cleaning a grease-lubricated bearing used in a wind turbine, which comprises an inner ring and an outer ring capable of turning relative to each other, comprising:
A receiving member installation step of installing a receiving member so as to face a discharge portion provided at a lower portion of the bearing from below in a state where a vertical surface with respect to a central axis of the bearing is substantially horizontal;
After supplying the cleaning agent to the supply portion provided on the upper portion of the bearing, the inner ring and the outer ring are relatively swirled to stir the grease to soften the grease, and the grease discharged from the discharge portion is discharged. A cleaning step of collecting a mixture with a cleaning agent by the receiving member,
Equipped with.

According to the above method (1), the cleaning agent is supplied to the inside of the grease lubrication type bearing from above. By relatively rotating the inner ring and the outer ring of the bearing in this state, the grease and the cleaning agent are mixed (stirred) inside the bearing, and the grease is softened. By arranging the receiving member in advance at the position facing the discharge part of the bearing from the lower side, the mixture of grease and cleaning agent mixed inside the bearing is collected by falling from the discharge part to the receiving member. To be done. By adopting such a method, the grease used for the bearing can be effectively washed.

(2) In some embodiments, in the method of (1) above,
The supply part is an upper gap formed between the inner ring and the outer ring,
In the cleaning step, the cleaning agent is supplied to a plurality of locations along the circumferential direction of the upper gap.

According to the above method (2), the cleaning agent is supplied to the upper clearance formed between the inner ring and the outer ring. By supplying such a cleaning agent to a plurality of locations along the circumferential direction of the upper clearance, the cleaning agent can be spread over a wide range inside the bearing.

(3) In some embodiments, in the above method (1) or (2),
The discharge portion is a lower gap formed between the inner ring and the outer ring,
The receiving member extends over the entire circumferential direction along the lower gap.

According to the above method (3), the receiving member for collecting the mixture is provided over the entire circumferential direction along the shape of the lower gap formed between the inner ring and the outer ring from which the mixture is discharged. As a result, it is possible to accurately collect the mixture discharged from the lower clearance.

(4) In some embodiments, in any one of the methods (1) to (3) above,
The receiving member is supported on the bearing or a peripheral member of the bearing via a magnet.

According to the above method (4), the receiving member used for collecting the mixture discharged from the bearing is attached to the bearing or the peripheral member of the bearing by the magnetic force of the magnet. Therefore, since the receiving member is detachably attached, it is easy to handle.

(5) In some embodiments, in any one of the methods (1) to (4) above,
The washing process is repeated multiple times.

According to the above method (5), the grease existing inside the bearing can be accurately discharged to the outside by repeating the above-mentioned cleaning step.

(6) In some embodiments, in any one of the methods (1) to (5) above,
In the cleaning step, the mixture is discharged by sucking the mixture with a suction device while the bearing is sealed.

According to the above method (6), by using a suction device when discharging the mixture, the negative pressure can be utilized to efficiently discharge the mixture.

(7) In some embodiments, in the above method (6),
The suction device is connected to the discharge part via a flexible tube.

According to the method of (7) above, the suction device is connected to the discharge part through which the mixture is discharged via the flexible tube. Therefore, the position of the suction device can be flexibly changed in a limited work area.

(8) In some embodiments, in any one of the methods (1) to (7) above,
The bearing is a pitch bearing in which a wind turbine blade is connected to one of the inner ring and the outer ring and a hub is connected to the other.

According to the above method (8), the bearing can be cleaned with grease in the pitch bearing that supports the wind turbine blade so as to be capable of pitch rotation with respect to the hub.

(9) In some embodiments, in the above method (8),
The method may further include a rotating step of rotating the hub so that the vertical surface is substantially horizontal.

According to the above method (9), when the surface perpendicular to the central axis of the bearing is in a non-horizontal state, it can be adjusted to be substantially horizontal by rotating the hub.

(10) In some embodiments, in the above method (8) or (9),
The pitch bearing is configured to be movable between a feather state and a fine state by rotating the wind turbine blade with respect to the hub,
In the cleaning step, the inner wheel and the outer wheel are relatively turned within a predetermined drive range from the feather state.

According to the above method (10), when the inner ring and the outer ring are relatively rotated while the cleaning agent is supplied to the inside of the bearing, the drive range of the bearing is limited to a predetermined drive range based on the feather state. To do. By setting this drive range sufficiently narrow, it is possible to reduce the force generated by the wind acting on the wind turbine blades when relatively turning the inner and outer wheels, so that the wind energy that the hub rotates during work can be reduced. Can be effectively prevented.

(11) In some embodiments, in any one of the methods (1) to (7) above,
The bearing is a yaw bearing in which the tower of the wind turbine is connected to one of the inner ring and the outer ring and a nacelle is connected to the other.

According to the above method (11), in the yaw bearing that rotatably supports the nacelle with respect to the tower of the wind turbine, the bearing can be cleaned with grease.

(12) In some embodiments, in the above method (1),
In the cleaning step, the cleaning agent is supplied at a higher flow rate.

According to the above method (12), in the cleaning step, by supplying the cleaning agent at a higher flow rate, the grease remaining inside the bearing can be more effectively discharged. The spraying of the cleaning agent having such a high flow velocity can be realized by, for example, spraying with a sprayer, pressurization with a pump, or spraying from a thin tip such as a nozzle.

(13) In some embodiments, in the above method (12),
In the cleaning step, the mixture is discharged by sucking the mixture with a suction device while the bearing is sealed.

According to the above method (13), by using the suction device when discharging the mixture, the negative pressure can be utilized to efficiently discharge the mixture.

(14) In some embodiments, in the method according to any one of (1) to (13), after the cleaning step, a second cleaning agent different from the cleaning agent is supplied to the supply unit, The method further comprises a cleaning step of discharging a mixture of the grease and the second cleaning agent from the discharging section.

According to the above method (14), after the cleaning step, different cleaning agents are further supplied to the supply section by different methods, and the cleaning step is changed to more effectively discharge the grease remaining inside the bearing. can do.

(15) In some embodiments, in the above method (6) or (13),
The suction device is connected to the discharge part via a flexible tube.

According to the method of (15) above, the suction device is connected to the discharge part through which the mixture is discharged via the flexible tube. Therefore, the position of the suction device can be flexibly changed in a limited work area.

According to at least one embodiment of the present invention, it is possible to provide a bearing cleaning method capable of efficiently cleaning grease used for pitch bearings or yaw bearings of wind turbines.

It is the whole wind power generator lineblock diagram. It is a front view of the wind power generator of FIG. It is a flowchart which shows the bearing cleaning method which concerns on at least one embodiment of this invention for every process. It is a flowchart which shows the washing|cleaning process S100 of FIG. 3 for every process. It is sectional drawing which shows the installation position of the receiving member in step S105 of FIG. 4 from a side. It is the sectional view on the AA line of FIG. It is an expanded sectional view of the B area|region of FIG. FIG. 6 is a top view showing the supply unit formed in step S106 of FIG. 4. 5 is an example of a supply tool used in step S107 of FIG. 4. It is a flow chart which shows the 2nd washing process S200 of Drawing 3 for every process. It is a schematic diagram which shows a mode that a cleaning process S100 is implemented with respect to the yaw bearing of FIG. It is an expanded sectional view of the D area|region of FIG.

Embodiments of the present invention will be described below with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention thereto unless specifically stated, and are merely illustrative examples. Only.

First, the object of implementation of the bearing cleaning method according to at least one embodiment of the present invention will be described. In the following description, a wind turbine generator will be described as an example of a wind turbine including a bearing that is an implementation target. However, the present invention can be widely applied to other devices including a grease lubrication type bearing including other regenerative energy type power generators such as tidal current power generators, ocean current power generators and river current power generators. Alternatively, the present invention is also applicable to bearings that require swiveling, such as swivel cranes, excavators, and lifts, in which large bearings with a diameter of 500 mm or more cannot be easily replaced unless the surrounding large structure is disassembled.

1 is an overall configuration diagram of the wind turbine generator 1, and FIG. 2 is a front view of the wind turbine generator 1 of FIG. The wind turbine generator 1 includes a rotor 3 including a wind turbine blade 2 and a hub 4, a rotary shaft 6 connected to the hub 4 of the rotor 3, a generator 16 that generates electric power, and a rotary energy of the rotary shaft 6. The speed increaser 10 which transmits to the generator 16 at a predetermined speed increase ratio.
The hub 4 is covered with a spinner 5.

In the wind turbine generator 1, as shown in FIG. 2, when viewed from the front, the three wind turbine blades 2 (2a, 2b, 2c) are attached to the hub 4 at equal intervals (120 degree intervals). .. These wind turbine blades 2 have the same length in the longitudinal direction, and are connected to the hub 4 via pitch bearings 100 at each blade root 7. In the present embodiment, the wind turbine blade 2 and the hub 4 are fixed to the inner ring and the outer ring of the pitch bearing 100, respectively, so that the wind turbine blade 2 has a pitch direction (around the longitudinal axis) with respect to the hub 4. ) Can be turned. The pitch angle of the wind turbine blade 2 with respect to the hub 4 is variable by an actuator (not shown), and the wind energy received by the wind turbine blade 2 can be adjusted by controlling the pitch angle between the feather state and the fine state. There is.

Further, as shown in FIG. 1, the rotary shaft 6 connected to the rotor 3 is provided by a main shaft bearing 20 housed in a bearing box 19 in a nacelle 30 installed on a tower 8 standing on the sea or on the ground. The nacelle 30 is rotatably supported. The bearing box 19 is supported by the nacelle base plate 30A of the nacelle 30.

The nacelle 30 is rotatably installed on the tower 8 via the yaw bearing 200. The nacelle 30 is configured to be rotatable in the yaw direction with respect to the tower 8 by fixing the tower 8 and the nacelle 30 to the inner ring and the outer ring of the yaw bearing 200, respectively. The yaw angle of the nacelle 30 with respect to the tower 8 is variable by an actuator (not shown), and by controlling the nacelle direction, the rotor 3 supported by the nacelle 30 follows the wind received by the wind turbine generator 1. It is configured to be turnable.

Next, a process of cleaning the pitch bearing 100 using the bearing cleaning method according to at least one embodiment of the present invention will be specifically described. FIG. 3 is a flow chart showing each step of the bearing cleaning method according to at least one embodiment of the present invention. The bearing cleaning method includes a case where only the cleaning step S100 is performed in which cleaning is performed using a cleaning agent, or a case where a second cleaning step S200 is performed in which cleaning is performed using a second cleaning agent. As shown in FIG. 3, the cleaning step S100 and the second cleaning step S200 can be sequentially performed to clean the pitch bearing 100 in multiple stages.

Next, the specific content of the cleaning step S100 will be described. FIG. 4 is a flowchart showing the cleaning step S100 of FIG. 3 for each step.

First, the pitch bearing 100 to be cleaned is specified (step S101), and the attitude of the pitch bearing 100 is confirmed (step S102). Specifically, as shown in FIG. 2, of the three wind turbine blades 2a, 2b, 2c attached to the hub 4, one wind turbine blade 2 to be cleaned is specified, and the specified wind turbine blade 2 is specified. Is determined with respect to the hub 4. As a result, the posture of the pitch bearing 100 corresponding to the wind turbine blade 2 to be cleaned is specified.

Then, it is determined whether the bearing surface 102 of the pitch bearing 100 is substantially horizontal based on the attitude of the pitch bearing 100 specified in step S102 (step S103). The bearing surface 102 of the pitch bearing 100 is defined as a surface perpendicular to the central axis C of the pitch bearing 100, as shown in FIG. 5 described later. In the example of FIG. 2, the wind turbine blade 2a is located at a position of an angle of 0 degree with respect to the vertical direction, so that the bearing surface 102 of the pitch bearing 100 is substantially horizontal. Since the one wind turbine blades 2b and 2c are located at positions of 120 degrees and 240 degrees with respect to the vertical direction, the bearing surface 102 of the pitch bearing 100 is not horizontal.
In step S103, it may be determined whether or not the bearing surface 102 is strictly horizontal. Alternatively, it may be determined whether or not the bearing surface 102 is within a predetermined angle range from the horizontal. Good.

Then, when the bearing surface 102 of the pitch bearing 100 is substantially horizontal (step S103: YES), the process proceeds to step S105 described later. Referring to FIG. 2 as an example, when the pitch bearing 100 corresponding to the wind turbine blade 2a is to be cleaned, since the bearing surface 102 of the pitch bearing 100 is substantially horizontal, the following step S104 is omitted and step S105 is performed. Is carried out.

On the other hand, when the bearing surface 102 of the pitch bearing 100 is not horizontal (step S103: NO), the hub 4 is rotated so that the bearing surface 102 of the pitch bearing 100 becomes substantially horizontal (step S104). Referring to FIG. 2 as an example, when the pitch bearing 100 corresponding to the wind turbine blades 2b and 2c is to be cleaned, the bearing surface 102 of the pitch bearing 100 is non-horizontal, so step S104 is performed. Accordingly, by moving the wind turbine blades 2b, 2c to the position at an angle of 0 degree with respect to the vertical direction (that is, the position of the wind turbine blade 2a in FIG. 2), the bearings of the pitch bearing 100 corresponding to the wind turbine blades 2b, 2c. The surface 102 can be substantially horizontal.

The rotation operation of the hub 4 in step S104 is performed, for example, by adjusting the wind energy received by the wind turbine blade 2 by controlling the pitch angle of the wind turbine blade 2 with respect to the hub 4 while allowing the rotation of the rotor 3. Alternatively, when the wind turbine generator 1 includes a turning device, it may be performed by controlling the turning device. Alternatively, if an inverter type power generation system is adopted, the inverter may be operated to rotate the generator and rotate the rotor.

In addition, in the following steps, the rotation of the rotor 3 may be prohibited in order to stably maintain the posture of the bearing surface 102 which is substantially horizontal as described above. Such prohibition of rotation of the rotor 3 is realized by using, for example, a lock mechanism or a braking mechanism (not shown).

Then, the receiving member 110 is installed below the pitch bearing 100 to be cleaned (step S105). 5 is a sectional view showing the installation position of the receiving member 110 in step S105 of FIG. 4 from the side, FIG. 6 is a sectional view taken along the line AA of FIG. 5, and FIG. 7 is a region B of FIG. FIG.

The pitch bearing 100 has a structure in which a rolling element 108 is held between an inner ring 104 and an outer ring 106 that can rotate relative to each other. The rolling element 108 is housed in an internal space 105 (see FIG. 7) formed between the inner ring 104 and the outer ring 106, and grease (not shown) for lubrication is injected into the internal space 105. There is. The inner ring 104 is fixed to the wind turbine blade 2 by a bolt 103a, and the outer ring 106 is fixed to the hub 4 by a bolt 103b. By disposing such a pitch bearing 100 between the hub 4 and the wind turbine blade 2, the wind turbine blade 2 fixed to the inner ring 104 is arranged in the pitch direction (wind turbine blade) with respect to the hub 4 fixed to the outer ring 106. It is configured to be rotatable about the central axis of 2).

Note that the pitch bearing 100 can adopt various forms such as a ball bearing, a double-row cylindrical roller bearing, and a cross roller bearing depending on the shape of the rolling elements 108.

In step S105, as shown in FIG. 7, in the inner space 4a of the hub 4, the receiving member 110 is installed so as to face the discharge portion 120 provided below the pitch bearing 100. The discharge part 120 has a discharge path 122 communicating with the internal space 105 of the pitch bearing 100. The discharge passage 122 is provided with an oil seal member 124 for preventing the grease existing in the internal space 105 from leaking to the outside. The mixture 52 of the grease and the cleaning agent 50 is discharged from the discharge section 120, and the receiving member 110 is arranged at a position where the discharged mixture 52 can be received.

The discharge path 122 of the discharge part 120 uses a gap existing between the inner ring 104 and the outer ring 106 of the pitch bearing 100, and opens in a ring shape along the circumferential direction of the wind turbine blade 2. Therefore, the receiving member 110 also extends in a ring shape along the circumferential direction of the wind turbine blade 2 so as to correspond to such a gap.

As shown in FIG. 7, the receiving member 110 arranged in the hub 4 has its end portion in close contact with the surroundings (the inner ring 104 and the inner wall of the hub 4), so that the mixture 52 discharged from the discharging portion 120 is surrounded. However, the receiving member 110 may be disposed apart from the surroundings (the inner ring 104 and the inner wall of the hub 4).

The receiving member 110 is directly or indirectly supported on the hub 4 side. In the example of FIG. 7, the receiving member 110 is stably supported by the inner wall 4b of the hub 4 via the support member 112. The support member 112 includes an arm portion 112a connected to the receiving member 110, and a magnet portion 112b provided on the side of the arm portion 112a opposite to the receiving member 110. The magnet portion 112b is configured to include a permanent magnet and is detachably attached to the inner wall 4b of the hub 4 by magnetic force.
The arm portion 112a may be rigid or flexible.

A flexible tube 114 for sending the mixture received by the receiving member 110 to a container 116 for collection is connected to the bottom of the receiving member 110. As a result, the mixture discharged to the receiving member 110 is collected in the container 116 from the bottom of the receiving member 110 through the flexible tube 114. The flexible tube 114 is made of a flexible material such as vinyl hose or bellows pipe. Therefore, the container 116, which is the collection destination of the mixture, can be flexibly arranged in the hub 4 at a position where it does not interfere with other structures such as the structure.

Then, the supply part 130 is formed in the upper part of the pitch bearing 100 (step S106). The supply unit 130 is configured to supply the cleaning agent 50 to the internal space 105 of the pitch bearing 100, and opens upward. Here, FIG. 8 is a top view showing the supply unit 130 formed in step S106 of FIG.
Note that, in FIG. 8, the wind turbine blades 2 connected to the inner ring 104 of the pitch bearing 100 are omitted in order to clearly show the supply unit 130.

The supply unit 130 is formed by using the supply passage 132 that is a gap existing between the inner ring 104 and the outer ring 106 that form the pitch bearing 100 (see FIG. 7 ). Like the discharge passage 122, the supply passage 132 opens in a ring shape along the circumferential direction of the wind turbine blade 2 and is normally sealed by an oil seal member (not shown). By opening the supply passage 132 to the outside by removing the oil seal member, as shown in FIG. 8, a supply portion 130 that opens upward in a ring shape is formed.

Then, the cleaning agent 50 is supplied to the supply part 130 formed in step S106 (step S107). As shown in FIG. 7, the supply of the cleaning agent 50 is performed from the upper side with respect to the supply unit 130. The cleaning agent is a liquid having a lower base oil viscosity than the existing grease used for the pitch bearing 100, and is, for example, a lubricating oil having a low viscosity. The cleaning agent 50 supplied to the supply unit 130 is guided to the internal space 105 of the pitch bearing 100 via the supply path 132. The cleaning agent can also be sprayed at a higher flow rate. Such spraying of the cleaning agent can be realized, for example, by spraying with a sprayer, pressurizing with a pump, or spraying from a thin tip such as a nozzle.

As described above, the supply unit 130 has the supply path 132 that opens in a ring shape along the circumferential direction of the wind turbine blade 2. Therefore, the supply of the cleaning agent 50 in step S107 can be performed to any position of the ring-shaped supply passage 132. For example, in FIG. 8, a workbench 4c accessible via the internal space 4a of the hub 4 is provided on the front surface on the outer surface of the hub 4, and the workbench 4c is supplied by the worker who has reached the workbench 4c. The cleaning agent 50 can be supplied to any position of the portion 130. Alternatively, it can be supplied from the top side of the nacelle cover.

The supply of the cleaning agent 50 to the supply unit 130 may be performed at a plurality of positions along the circumferential direction, as indicated by the arrow in FIG. Thereby, the cleaning agent can be spread over a wide range of the pitch bearing 100. The range in which the cleaning agent 50 can be supplied is limited to the range accessible from the workbench 4c, but the range can be effectively expanded by using a predetermined supply tool 140.

FIG. 9 shows an example of the supply tool 140 used in step S107 of FIG. The supply tool 140 includes a supply pipe 142 having a supply port 141 to which the cleaning agent 50 is supplied, a tank section 144 communicating with the supply tube 142 and configured to temporarily store the cleaning agent 50, and a tank section. And a plurality of pipes 146 that communicate with 144 and branch into an octopus shape. A magnet portion 147 is provided at the tip of the plurality of pipes 146, and is configured to be detachably fixed to the supply portion 130 of the pitch bearing 100 to which the cleaning agent 50 is to be supplied. In step S107, the cleaning agent 50 supplied to the supply pipe 142 is supplied by inclining the plurality of pipes 146, for example, by attaching the magnet parts 147 to a plurality of positions along the circumferential direction of the ring-shaped supply part 130. The cleaning agent can be spread over a wide area of the portion 130. By using such a supply tool 140, the cleaning agent 50 can be supplied to a wide range of the pitch bearing 100 from a limited work space such as the workbench 4c. Or, if you have a scaffold, you can supply it little by little with a watering can.

Each pipe 146 is provided with a cock 148 for adjusting the flow rate of the cleaning agent 50. Accordingly, the cleaning agent 50 can be supplied at a predetermined flow rate to each position of the supply unit 130 at the tip of which the plurality of pipes 146 are attached.

Then, the inner ring 104 and the outer ring 106 of the pitch bearing 100 are relatively turned (step S108). At this time, since the cleaning agent 50 supplied in step S107 is present in the internal space 105 of the pitch bearing 100 together with the grease (including the dirt component) for lubricating the pitch bearing 100, the inner ring 104 and the outer ring 106 are relatively opposed to each other. It is agitated by rotating normally. As a result, the grease becomes a mixture 52 with the cleaning agent 50 and is softened.

Relative turning of the inner ring 104 and the outer ring 106 in step S108 is performed by a pitch actuator.

The number of times of relative rotation of the inner ring 104 and the outer ring 106 in step S108 can be adjusted as necessary. That is, it is preferable to set the number of relative swiveling drives (for example, 5 times) so that the grease and the cleaning agent 50 are sufficiently stirred in the internal space 105 of the pitch bearing 100.

Then, the mixture 52 is discharged from the discharge part 120 provided under the pitch bearing 100 (step S109). The discharge part 120 is a structure for discharging the mixture 52 (grease and cleaning agent 50) stored in the internal space 105 of the pitch bearing 100 to the outside, and as described above with reference to FIG. 6, the pitch bearing. The discharge passage 122 communicates with the internal space 105 of 100 and an oil seal member 124 provided at the outlet of the discharge passage 122. Press the oil seal with a spatula etc. to make a gap and discharge it, or remove the oil seal partially and discharge the oil.

In step S109, the mixture 52 existing in the internal space 105 may be discharged by completely opening the discharge passage 122 by removing the oil seal member 124 from the discharge passage 122.

The mixture 52 thus discharged from the discharge part 120 is received by the receiving member 110 installed in step S105, and is collected in the container 116 through the flexible tube 114 (step S110).

The discharge/collection of the mixture 52 in steps S109 and S110 may be performed by applying a negative pressure to the discharge part 120 to suck out the mixture 52 from the internal space 105. In this case, a negative pressure can be applied to the discharge part 120 via the flexible tube 114 by using a container-containing suction device as the container 116 in FIG. 7. At this time, the receiving member 110 seals the pitch bearing 100 by bringing the end portion into close contact with the surrounding pitch bearing 100 or the hub 4 as shown in FIG. You may make it operate effectively. Alternatively, the suction may be performed directly from above.

The sealed state of the pitch bearing 100 can be further improved by returning the seal member (not shown) removed from the supply passage 132 when the supply portion 130 is formed in step S106. Thereby, the negative pressure can be more effectively applied to the discharge part 120.

Then, the above steps S107 to S110 are repeated as necessary (step S111). The number of repetitions in step S111 may be arbitrary, but may be repeated until the amount of grease contained in the mixture 52 discharged from the discharging section 120 becomes sufficiently small, for example. By repeating the cleaning process in this manner, the grease present in the internal space 105 of the pitch bearing 100 can be effectively washed out.

Then, the 2nd washing process S200 performed after the above-mentioned washing process S100 is explained. FIG. 10 is a flowchart showing the second cleaning step S200 of FIG. 3 for each step.

In the second cleaning step S200, the second cleaning agent 60 is supplied from the supply unit 130 to the internal space 105 of the pitch bearing 100 by a method different from the previous cleaning step, for example, the previous cleaning step is a gravity drop type. If so, it may be supplied by spraying (step S201). When performing the second cleaning process S200 after the cleaning process S100, the supply unit 130 can also share the one already formed in step S106 of FIG. The second cleaning agent 60 may be the same as or different from the cleaning agent 50. The second mixture may be discharged by a method different from the previous cleaning step, for example, a suction method if the previous cleaning step is a gravity drop method (step S202).

The previous cleaning step is a weight drop type, first the grease is relatively swirled between the inner ring and the outer ring to stir the grease to soften the grease, and then in the second cleaning step, by spraying the second cleaning agent 60. By supplying the second cleaning agent 60 having a higher pressure to the internal space 105, it is possible to further wash away the grease that cannot be completely cleaned in the previous cleaning step S100. Further, in the second cleaning step, the inner ring and the outer ring may be relatively swirled and stirred to soften the grease.

The supply of the second cleaning agent 60 in step S201 is performed at a plurality of positions along the circumferential direction with respect to the ring-shaped supply portion 130, similarly to the supply of the cleaning agent 50 in step S107 of the cleaning step S100. May be.

In addition, when the second cleaning agent 60 is sprayed, the rolling element 108 in the internal space 105 of the pitch bearing 100 may be aimed from the supply unit 130. In this case, the second cleaning agent 60 uses a tapered nozzle that can be inserted into the supply path 132 of the supply unit 130, so that the second cleaning agent 60 can be directly sprayed onto the rolling elements 108 or adjacent rolling elements can be separated from each other. The grease existing around the rolling element 108 can be accurately washed out by spraying with aiming at the gap between the rolling elements. The example of spraying the second cleaning step may be applied to the previous cleaning step, and the second cleaning step may be omitted.

Subsequently, the second cleaning agent 60 supplied in step S201 forms a second mixture by mixing with the grease in the internal space 105 of the pitch bearing 100, and is discharged from the discharge part 120 to the outside (step S202). ). Then, the second mixture discharged to the outside from the discharge section 120 is received by the receiving member 110 installed in S105 of the cleaning step S100, and is collected in a predetermined container 116 via the flexible tube 114 as shown in FIG. Is performed (step S203).

Note that the discharge/collection of the second mixture in steps S202 and S203 is also performed from the internal space 105 by applying a negative pressure to the discharge part 120, similarly to steps S109 and S110 of the above-described cleaning step S100. It may be carried out by sucking out the two mixtures.

In the above-described embodiment, the case where the bearing cleaning method is applied to the pitch bearing 100 has been described, but the same can be applied to other bearings. Here, as another example, a bearing cleaning method using the yaw bearing 200 of the wind turbine generator 1 as a cleaning target will be briefly described below. 11 is a schematic view showing an example of installation of the receiving member 110 with respect to the yaw bearing 200 of FIG. 1, and FIG. 12 is an enlarged cross-sectional view of the area D of FIG.

As described above with reference to FIG. 1, the yaw bearing 200 is a bearing for pivotally supporting the nacelle 30 with respect to the tower 8 installed on the sea or on land. The yaw bearing 200 also includes an inner ring 202 connected to the tower 8, an outer ring 204 connected to the nacelle 30, and a rolling element 206 housed in an internal space provided between the inner ring 202 and the outer ring 204. The grease-lubricated bearing has a similar structure to the pitch bearing 100. By fixing the tower 8 and the nacelle 30 to the inner ring 202 and the outer ring 204 of the yaw bearing 200, respectively, the nacelle 30 is configured to be rotatable in the wind direction with respect to the tower 8. Depending on the structure of the wind turbine, there is also a structure in which the inner ring and the outer ring are attached to the nacelle and the tower, respectively.

As shown in FIG. 12, an internal space 205 exists between the inner ring 202 and the outer ring 204 of the yaw bearing 200, and grease (not shown) for lubrication is filled therein. As in the case of the pitch bearing 100 described above, a supply portion 210 using a communication passage 208 extending upward from the internal space 205 can be formed in the upper portion of the yaw bearing 200. Further, at the lower part of the yaw bearing 200, a discharge part 214 using a communication passage 212 extending downward from the internal space 205 can be formed. The supply unit 210 and the discharge unit 214 are configured to include the communication passages 208 and 212 as in the case of the pitch bearing 100 described above, and an oil seal member (not shown) that seals the communication passages 208 and 212 as needed. It may be configured by removing.

Since the yaw bearing 200 has a structure similar to that of the pitch bearing 100 described above, the above-described bearing cleaning method can be applied similarly to the pitch bearing 100. Although not described in detail, the receiving member 110 used at the time of cleaning is installed so as to face the ring-shaped discharge portion 214 from the lower side as shown in FIGS. 11 and 12. Then, in the cleaning step S100, the cleaning agent 50 is supplied from the supply unit 210, the inner ring 202 and the outer ring 204 are relatively swung, and then the mixture 52 discharged from the discharge unit 214 is collected by the receiving member 110. Further, similarly to the pitch bearing 100, the second cleaning step S200 may be provided.

As described above, according to the above-described embodiment, the pitch bearing 100 or the yaw bearing 200 can be cleaned in multiple stages by repeating the cleaning process or performing the cleaning process together with the second cleaning process. .. As a result, the grease used for the pitch bearing 100 or the yaw bearing 200 of the wind turbine generator 1 can be efficiently washed.

At least one embodiment of the present invention is applicable to a bearing cleaning method for cleaning a grease lubricated bearing.

DESCRIPTION OF SYMBOLS 1 Wind turbine generator 2 Wind turbine blades 3 Rotor 4 Hub 4c Work table 5 Spinner 6 Rotating shaft 7 Blade root 8 Tower 10 Speed increaser 16 Generator 20 Main shaft bearing 30 Nacelle 100 Pitch bearing 102 Bearing surface 110 Receiving member 112 Support member 112a Arm Part 112b Magnet part 114 Flexible tube 120 Ejection part 122 Ejection path 130 Supply part 132 Supply path 140 Supply tool 141 Supply port 142 Supply pipe 144 Tank part 146 Piping 147 Magnet part 148 Cock 200 Yaw bearing 210 Supply part 214 Discharge part

Claims (15)

A bearing cleaning method for cleaning a grease-lubricated bearing used in a wind turbine, which comprises an inner ring and an outer ring capable of rotating relative to each other.
A receiving member installation step of installing a receiving member so as to face a discharge portion provided at a lower portion of the bearing from a lower side in a state where a vertical surface with respect to a central axis of the bearing is substantially horizontal;
After supplying the cleaning agent to the supply section provided on the upper part of the bearing, the inner ring and the outer ring are relatively swirled to stir the grease to soften the grease, and the grease discharged from the discharge section A cleaning step of collecting a mixture with the cleaning agent by the receiving member,
A bearing cleaning method comprising: The supply part is an upper gap formed between the inner ring and the outer ring,
The bearing cleaning method according to claim 1, wherein in the cleaning step, the cleaning agent is supplied to a plurality of locations along the circumferential direction of the upper gap. The discharge portion is a lower gap formed between the inner ring and the outer ring,
The bearing cleaning method according to claim 1 or 2, wherein the receiving member extends over the entire circumferential direction along the lower gap. The bearing receiving method according to claim 1, wherein the receiving member is supported with respect to the bearing or a peripheral member of the bearing via a magnet. The bearing cleaning method according to claim 1, wherein the cleaning step is repeated a plurality of times. The bearing cleaning method according to any one of claims 1 to 5, wherein, in the cleaning step, the mixture is discharged by sucking the mixture using a suction device while the bearing is sealed. The bearing cleaning method according to claim 6, wherein the suction device is connected to the discharge portion via a flexible tube. The bearing cleaning method according to any one of claims 1 to 7, wherein the bearing is a pitch bearing in which a wind turbine blade is connected to one of the inner ring and the outer ring and a hub is connected to the other. The bearing cleaning method according to claim 8, further comprising a rotating step of rotating the hub so that the vertical surface is substantially horizontal. The pitch bearing is configured to be movable between a feather state and a fine state by rotating the wind turbine blade with respect to the hub,
The bearing cleaning method according to claim 8 or 9, wherein in the cleaning step, the inner ring and the outer ring are relatively swung within a predetermined drive range from the feather state. The bearing cleaning method according to any one of claims 1 to 7, wherein the bearing is a yaw bearing in which the tower of the wind turbine is connected to one of the inner ring and the outer ring and a nacelle is connected to the other. The bearing cleaning method according to claim 1, wherein in the cleaning step, the cleaning agent is supplied at a higher flow rate. The bearing cleaning method according to claim 12, wherein, in the cleaning step, the mixture is discharged by sucking the mixture using a suction device while the bearing is sealed. After the cleaning step, the method further comprises a cleaning step of supplying a second cleaning agent different from the cleaning agent to the supply unit and discharging a mixture of the grease with the second cleaning agent from the discharge unit. The bearing cleaning method according to any one of claims 1 to 13. The bearing cleaning method according to claim 6 or 13, wherein the suction device is connected to the discharge portion via a flexible tube.

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