Core penetrating method for main motor of heavy plate mill

Abstract

The invention relates to a core penetrating method for a main motor of a heavy plate mill. The core penetrating method comprises the following steps of 1, construction preparation; step 2, stator installation; 3, balancing the rotor; 4, performing primary core penetration on the rotor; step 5, secondary core penetration of the rotor; and 6, the rotor and the stator are lowered and positioned. The fixing cable is added in the core penetrating process, so that the stability of the rotor in the whole core penetrating process is greatly enhanced, and collision between the rotor and the stator in the core penetrating process is effectively avoided; the rotor sling adopts a mode that a short sling is matched with an electric chain block, so that the length of the sling is greatly shortened, and the whole descending process is more accurate, quicker and more reliable through the control of the electric chain block in the descending process of the stator and the rotor; when a sling hanging point is switched from primary core penetration to secondary core penetration, an air relay mode is utilized, a rotor does not need to be temporarily fixed through a cushion block, replacement of the sling hanging point is directly completed, and the whole switching process is more economical, rapid and reliable.

Description

Technical Field

[0001] The invention relates to the technical field of installation of a main motor of a rolling mill, in particular to a core threading method of a main motor of a thick plate rolling mill. Background Art

[0002] At present, wide and thick plate production lines generally use double-frame four-roll reversible rolling mills, which are divided into roughing mills and finishing mills. This type of rolling mill has two working rolls and two support rolls. The two working rolls are driven by large motors respectively. The motors generally use AC speed-regulating synchronous motors. The motors are usually arranged front and back and up and down. The front lower motor is used to drive the lower working roll of the rolling mill, and the rear upper motor is used to drive the upper working roll of the rolling mill.

[0003] Due to the large overall size and weight of the main motor of the wide and thick plate rolling mill, large lifting machinery is required for overall hoisting. At the same time, since the installation of the main motor has high requirements for the external environment such as air humidity and cleanliness, it must be installed in a closed factory building, so it can only be hoisted using the crane installed in the factory building. In order to reduce the investment cost of lifting machinery and factory building construction, the lifting capacity of the crane in the factory building is generally set according to the needs of motor core pulling, which can only meet the hoisting of the motor rotor. At the same time, the maximum lifting height of the crane is determined according to the upper motor rotor limit minimum hoisting height.

[0004] At present, the installation of the main motor of the mainstream wide and thick plate rolling mill basically adopts the on-site online core-threading installation method. The overall installation sequence is to install the lower motor first, and then install the upper motor. The installation sequence of a single motor is to install the stator first, then thread the core to complete the installation of the rotor, and finally complete the installation of the motor accessories. The hoisting machinery uses the gantry crane in the main motor plant, and uses the balance beam with the sling and fall chain to complete the core threading. The existing technology has the following deficiencies:

[0005] 1. The existing balance beam rotor lifting point is fixed and determined in advance by calculation. If the types of on-site slings and fall chains change, the fixed lifting point cannot ensure the level of the balance beam, and can only adapt to the lifting of one type of motor rotor, which is not universal.

[0006] 2. Since the air gap between the rotor and the stator is small, generally about 10mm-20mm for large motors, the lifting device needs to be kept balanced and stable during the motor core threading process, that is, the rotor always remains horizontal during the core threading process, and the up and down, front and back swinging amplitude of the rotor during the movement cannot exceed the gap between the rotor and the stator to prevent the rotor and stator from colliding and damaging the equipment. The existing technology has not yet involved measures to maintain the balance and stability of the rotor during the lifting process.

[0007] 3. In the prior art, when the hanging point is changed after the core is passed once, the rotor needs to be temporarily supported to complete the change of the hanging point, and additional temporary facilities need to be added, which has poor stability and low efficiency.

[0008] 4. The rotor sling in the prior art adopts a hand chain hoist, which has poor stability and low construction efficiency during the lowering process of the rotor and stator. Summary of the invention

[0009] The technical problem to be solved by the present invention is to provide a core-threading method for a main motor of a thick plate rolling mill, which solves the technical problem of poor stability of a hoisting system in the prior art and improves the efficiency of core-threading construction.

[0010] The technical solution adopted by the present invention to solve the technical problem is: to provide a method for core threading of a main motor of a thick plate rolling mill, comprising the following steps:

[0011] Step 1: Construction preparation;

[0012] Including: handover of civil equipment foundation, plant closure, and plant crane acceptance. The handover of civil equipment foundation shall verify the elevation, center line, and outline size of the foundation, and the elevation and center line of the embedded bolts and anchor plates shall meet the design requirements of the drawings; the walls and roofs around the closed plant shall not leak, otherwise rainwater will enter the equipment base and cause the insulation of the motor bearing seat to fail; the plant crane must be accepted by the special inspection institute, and all performance indicators must meet the design requirements, and the crane must operate stably to ensure the safety of the lifting process. The crane is a gantry crane;

[0013] Step 2: stator installation;

[0014] First, install the motor base plate, measure and adjust the motor and install the stator and rotor bearing seats after they are qualified. The rotor bearing seat is only installed at the lower part of the bearing seat at the load end of the rotor, and the non-load end is not installed. Place two sets of pads at the four corners of the stator, the fixed pad plate set is placed at the bottom of the stator, and the lifting pad plate set is placed at the lower part of the stator lifting plate. A screw jack is set on the upper part of the lifting pad plate set, and the screw jack rod is in the raised state.

[0015] Step 3: rotor balancing;

[0016] First, hoist and shift the rotor from the transport rack to the core lifting position, place the rotor on two temporary rotor support frames, assemble the rotor non-load end bearing seat to the rotor non-load bearing as a counterweight for rotor hoisting, and assemble the extension shaft to the rotor load end bearing end face; hoist the balance beam by the gantry crane, hang three sets of rotor slings on the balance beam, connect the rotor non-load end bearing sling and the load end bearing sling to the rotor, and temporarily fix the first electric fall chain on the rotor extension shaft sling with its chain and hook on the balance beam; try to hoist the rotor, make the balance beam level by adjusting the position of the sling hanging on the balance beam, and make the rotor level by adjusting the fall chain on the sling;

[0017] Step 4: The rotor is threaded once;

[0018] Operate the gantry crane to slowly move the rotor toward the stator, and stop when the extended shaft of the rotor approaches the end face of the stator; adjust the elevation and horizontal distance of the rotor by raising and lowering the main hook of the gantry crane and moving the trolley to ensure that the center line of the rotor coincides with the center line of the stator;

[0019] Step 5: Rotor core insertion for the second time;

[0020] First, safely lower the chain and hook of the first electric fall chain on the rotor extension shaft sling, connect it to the short sling of the rotor extension shaft, tighten the first electric fall chain to put the entire rotor extension shaft sling in a stressed state, and relax the load-end bearing sling; then open the joint of the load-end bearing sling, straighten the two ends of the load-end bearing sling and fix them on the lower beams on both sides of the gantry crane. The height of the straightened load-end bearing sling should be higher than the top surface of the stator housing; adjust the second electric fall chain of the rotor non-load-end bearing sling and the first electric fall chain of the extension shaft end sling to make the rotor horizontal and in the center of the stator, add left and right fixed cables on both sides of the extension shaft, fix the left and right fixed cables on both sides on the lower beam of the gantry crane, and tighten the manual fall chains of the left and right fixed cables; jog the gantry crane to continue moving the rotor toward the inner cavity of the stator, and observe that there is a safe gap between the rotor and the stator while moving, until the center line of the rotor coincides with the center line of the stator;

[0021] Step 6: The rotor and stator are lowered into place.

[0022] As a supplement to the technical solution described in the present invention, in the step four, in order to ensure the stability of the rotor during the core threading process, a rear fixed cable and left and right fixed cables are added to the non-load bearing end of the rotor, the rear fixed cable is fixed to the anchor on the ground, and the left and right fixed cables are fixed to the bottom beam of the gantry crane; the left and right fixed cables are tightened by a manual fall chain, the rear fixed cable is first pre-tightened by the manual fall chain, and the wire rope is synchronously relaxed by the manual fall chain during the rotor core threading process to ensure that the rotor does not swing forward too much due to inertia when the gantry crane is moved.

[0023] As a supplement to the technical solution described in the present invention, in the step four, after the adjustment of the rotor center position is completed and the left and right fixing cables and the rear fixing cable are set, the gantry crane is operated to continue moving the rotor toward the stator inner cavity until the rotor load end bearing sling is close to the stator end face.

[0024] As a supplement to the technical solution described in the present invention, the specific steps of step six are as follows: slightly lift the screw jacks at the four corners of the stator, pull out a pad from the fixed pad group, and lower the screw jacks at the four corners at the same time. When the gap between the stator and rotor tops is 10 mm, stop lowering the screw jacks; operate the four electric fall chains on the sling to lower the rotor until the gap between the rotor and the lower part of the stator is 10 mm; repeat the above process until the screw jack push rod drops to the bottom position, use flat pads and inclined pads to fill the gap between the fixed pad group and the stator bottom plate tightly, pull out the pad of the lifting pad group located under the screw jack, push out the screw jack push rod, and loosen the fixed pad group and the stator bottom plate, repeat the above steps until all pads are pulled out, the stator is completely positioned on the motor bottom plate, and the rotor is positioned on the rotor bearing seat. At this point, the core penetration is completed, and the next step of adjusting the rotor and stator is entered.

[0025] Beneficial effects: The present invention relates to a method for core threading of the main motor of a thick plate rolling mill. A fixed rope is added during the core threading process, which greatly enhances the stability of the rotor during the entire core threading process and effectively avoids the collision between the rotor and the stator during the core threading process. The rotor sling adopts a short sling with an electric fall chain, which greatly shortens the length of the sling and can be controlled by the electric fall chain during the stator and rotor descent process, making the entire descent process more accurate, fast and reliable. When switching the sling hanging point from the primary core threading to the secondary core threading, the rotor does not need to be temporarily fixed with a pad, and the sling hanging point can be directly replaced, making the entire switching process more economical, fast and reliable. Therefore, this hoisting system makes the entire core threading process more reliable and stable, and also greatly improves the construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the main motor core threading flow chart of the present invention;

[0027] Figure 2 is a schematic diagram of the installation of the stator according to the present invention;

[0028] Figure 3 is a schematic diagram of the balance of the rotor described in the present invention;

[0029] Figure 4 It is a schematic structural diagram of the rotor core-piercing method according to the present invention;

[0030] Figure 5 It is a schematic structural diagram of the rotor secondary core penetration according to the present invention;

[0031] Figure 6 It is a schematic diagram of the arrangement of the rotor fixing rope according to the present invention.

[0032] Illustration: 1. Gantry crane, 2. Balance beam, 3. Rotor non-load end bearing sling, 4. Balance beam sling, 5. Rotor non-load end bearing seat, 6. Stator, 7. Extension shaft, 8. Rotor load end bearing sling, 9. Rotor, 10. Rotor extension shaft sling, 11. Rotor support frame, 12. Left and right fastening cables, 13. Rear fastening cable, 14. Ground anchor, 15. Fixed pad group, 16. Lifting pad group, 17. Screw jack, 18. Motor base plate, 31. Second electric fall chain, 91. Rotor non-load end bearing, 92. Rotor load end bearing, 101. First electric fall chain, 102. Extension shaft sling short sling, 122. Manual fall chain. DETAILED DESCRIPTION

[0033] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0034] The embodiment of the present invention relates to a method for core threading of a main motor of a thick plate rolling mill, such as Figure 1-6 As shown, the following steps are included:

[0035] Step 1: Construction preparation;

[0036] Including: handover of civil equipment foundation, plant closure, and plant crane acceptance. The handover of civil equipment foundation shall verify the elevation, center line, and outline size of the foundation, and the elevation and center line of the embedded bolts and anchor plates shall meet the design requirements of the drawings; the walls and roofs around the closed plant shall not leak, otherwise rainwater will enter the equipment base and cause the insulation of the motor bearing seat to fail; the plant crane must be accepted by the special inspection institute, and all performance indicators must meet the design requirements, and the crane must operate stably to ensure the safety of the lifting process. The crane is a gantry crane 1;

[0037] Step 2: stator installation;

[0038] First, install the motor base plate 18, and after the measurement and adjustment are qualified, install the stator 6 and the rotor bearing seat. The rotor bearing seat is only installed at the lower part of the bearing seat at the load end of the rotor, and the non-load end is not installed; two sets of pad groups are placed at the four corners of the stator, the fixed pad plate group 15 is placed at the bottom of the stator, and the lifting pad plate group 16 is placed at the lower part of the stator jacking plate, and a screw jack 17 is set on the upper part of the lifting pad plate group 16, and the screw jack 17 rod is in a raised state;

[0039] Step 3: Balancing of rotor 9;

[0040] First, the rotor 9 is hoisted and moved from the transport frame to the core lifting position, and the rotor 9 is placed on two temporary rotor support frames 11. The rotor non-load end bearing seat 5 is assembled to the rotor non-load bearing 91 as a counterweight for the rotor 9 hoisting, and the extension shaft 7 is assembled to the end face of the rotor load end bearing 92; the gantry crane 1 lifts the balance beam 2 through the balance beam sling, and three sets of rotor slings are hung on the balance beam 2, and the rotor non-load end bearing sling 3 and the load end bearing sling 8 are connected to the rotor 9. The first electric fall chain 101 on the rotor extension shaft sling 10 has its chain and hook temporarily fixed on the balance beam 2; the rotor 9 is hoisted for trial, and the balance beam 2 is made horizontal by adjusting the position of the sling hanging on the balance beam 2, and the rotor 9 is made horizontal by adjusting the fall chain on the sling;

[0041] Step 4: Rotor 9 is threaded once;

[0042] Operate the gantry crane 1 to slowly move the rotor 9 toward the stator 6, and stop moving when the extended shaft 7 of the rotor approaches the end surface of the stator 6; adjust the elevation and horizontal distance of the rotor 9 by raising and lowering the main hook of the gantry crane 1 and moving the trolley to ensure that the center line of the rotor 9 coincides with the center line of the stator 6;

[0043] Step 5: Rotor 9 is threaded through the core for the second time;

[0044] First, safely lower the chain and hook of the first electric fall chain 101 on the rotor extension shaft sling 10, connect it to the rotor extension shaft short sling 102, tighten the first electric fall chain 101 to put the entire rotor extension shaft sling 10 in a stressed state, and relax the load-end bearing sling 8; then open the joint of the load-end bearing sling 8, straighten the two ends of the load-end bearing sling 8 and fix them on the lower crossbeams on both sides of the gantry crane 1. The height of the straightened load-end bearing sling 8 should be higher than the top surface of the stator 6 housing; adjust the rotor non-load end The second electric fall chain 31 of the bearing sling 3 and the first electric fall chain 101 of the extended shaft end sling 10 make the rotor 9 horizontal and in the center of the stator 6, and the left and right fixed cables 12 are added on both sides of the extended shaft 7. The left and right fixed cables 12 are fixed on the lower crossbeam of the gantry crane 1, and the manual fall chains 122 of the left and right fixed cables 12 are tightened; the gantry crane 1 is moved to continue to move the rotor 9 into the inner cavity of the stator 6, and a safe gap is maintained between the rotor 9 and the stator 6 while moving, until the center line of the rotor 9 coincides with the center line of the stator 6;

[0045] Step 6: The rotor 9 and stator 6 are lowered into place.

[0046] In the step 4, in order to ensure the stability of the rotor 9 during the core threading process, a rear fixing cable 13 and left and right fixing cables 12 are added to the non-load bearing end 91 of the rotor, the rear fixing cable 13 is fixed to the anchor 14 on the ground, and the left and right fixing cables 12 are fixed to the bottom crossbeam of the gantry crane 1; the left and right fixing cables 12 are tightened by the manual fall chain 122, and the rear fixing cable 13 is first pre-tightened by the manual fall chain 122, and the wire rope is synchronously loosened by the manual fall chain 122 during the core threading process of the rotor 9, to ensure that the rotor 9 does not swing forward too much due to inertia when the gantry crane 1 is moved in an inching manner.

[0047] In step 4, after the center position of the rotor 9 is adjusted, the left and right fixing cables 12 and the rear fixing cable 13 are set, the gantry crane 1 is operated to move the rotor 9 further toward the inner cavity of the stator 6 until the load-end bearing sling 92 of the rotor 9 approaches the end face of the stator 9.

[0048] The specific steps of step six are as follows: slightly lift the screw jacks 17 at the four corners of the stator 6, pull out a pad of the fixed pad group 15, and at the same time lower the screw jacks 17 at the four corners. When the gap between the stator and rotor tops is about 10 mm, stop lowering the screw jacks 17; operate the four electric fall chains on the sling to lower the rotor 9 until the gap between the rotor 9 and the lower part of the stator 6 is about 10 mm; repeat the above process until the top rod of the screw jack 17 drops to the bottom position, use flat pads and inclined pads to fill the gap between the fixed pad group 15 and the bottom plate of the stator 6 tightly, pull out the pad of the lifting pad group 16 located under the screw jack 17, push out the top rod of the screw jack 17, and loosen the fixed pad group 15 and the bottom plate of the stator 6, repeat the above steps until all pads are pulled out, the stator 6 is completely positioned on the motor bottom plate 18, and the rotor 9 is positioned on the rotor bearing seat. At this point, the core is worn and the next step of adjusting the rotor 9 and the stator 6 is entered.

[0049] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0050] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0051] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0052] The above is a detailed introduction to a method for core threading of the main motor of a thick plate rolling mill provided by the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for core threading of a main motor of a thick plate rolling mill, characterized in that: The following steps are involved: Step 1: Construction preparation; It includes: handover of civil engineering equipment foundation, plant closure, and acceptance of plant cranes. The handover of civil engineering equipment foundations shall verify that the elevation, center line, and outline dimensions of the foundation, and the elevation and center line of the embedded bolts and anchor plates meet the design requirements of the drawings; the walls and roofs around the closed plant shall not leak, otherwise rainwater will enter the equipment base and cause the insulation of the motor bearing seat to fail; the plant crane must be accepted by the special inspection institute, and all performance indicators must meet the design requirements. The crane must operate stably to ensure the safety of the lifting process. The crane is a gantry crane (1); Step 2: stator installation; First, the motor base plate (18) is installed. After the motor is measured, adjusted and accepted, the stator (6) and the rotor bearing seat are installed. The rotor bearing seat is only installed at the lower part of the bearing seat at the load end of the rotor, and the non-load end is not installed. Two sets of pad groups are placed at the four corners of the stator. The fixed pad plate group (15) is placed at the bottom of the stator, and the lifting pad plate group (16) is placed at the lower part of the stator lifting plate. A screw jack (17) is arranged on the upper part of the lifting pad plate group (16), and the screw jack (17) rod is in a raised state. Step 3: Balancing the rotor (9); First, the rotor (9) is hoisted and moved from the transport frame to the core lifting position, and the rotor (9) is placed on two temporary rotor support frames (11). The rotor non-load end bearing seat (5) is assembled on the rotor non-load bearing (91) as a counterweight for the rotor (9) hoisting, and the extension shaft (7) is assembled on the end face of the rotor load end bearing (92); the gantry crane (1) hoists the balance beam (2), hangs three sets of rotor slings on the balance beam (2), connects the rotor non-load end bearing sling (3) and the load end bearing sling (8) to the rotor (9), and temporarily fixes the first electric fall chain (101) on the rotor extension shaft sling (10) with its chain and hook on the balance beam (2); the rotor (9) is hoisted for trial, and the balance beam (2) is horizontally adjusted by adjusting the position of the sling hanging on the balance beam (2), and the rotor (9) is horizontally adjusted by adjusting the fall chain on the sling; Step 4: The rotor (9) is threaded once; The gantry crane (1) is operated to slowly move the rotor (9) toward the stator (6), and the movement is stopped when the extended shaft (7) of the rotor approaches the end face of the stator (6); the elevation and horizontal distance of the rotor (9) are adjusted by raising and lowering the main hook of the gantry crane (1) and moving the trolley to ensure that the center line of the rotor (9) coincides with the center line of the stator (6); Step 5: Rotor (9) is threaded through the core for the second time; First, the chain and hook of the first electric fall chain (101) on the rotor extension shaft sling (10) are safely lowered and connected to the rotor extension shaft short sling (102), and the first electric fall chain (101) is tightened to put the entire rotor extension shaft sling (10) in a stressed state, and the load-end bearing sling (8) is relaxed; then, the joint of the load-end bearing sling (8) is opened, and the two ends of the load-end bearing sling (8) are straightened and fixed to the lower crossbeams on both sides of the gantry crane (1), and the height of the straightened load-end bearing sling (8) should be higher than the top surface of the stator (6) housing; the rotor non-load end bearing sling (3) is adjusted. The second electric fall chain (31) and the first electric fall chain (101) of the extension shaft end sling (10) make the rotor (9) horizontal and located at the center of the stator (6), and left and right fixed ropes (12) are added on both sides of the extension shaft (7), and both sides of the left and right fixed ropes (12) are fixed on the lower cross beam of the gantry crane (1), and the manual fall chains (122) of the left and right fixed ropes (12) are tightened; the gantry crane (1) is moved in a jog manner to continue to move the rotor (9) toward the inner cavity of the stator (6), and a safety gap is observed between the rotor (9) and the stator (6) while moving, until the center line of the rotor (9) coincides with the center line of the stator (6); Step 6: The rotor (9) and stator (6) are lowered into place.

2. A method for core threading of a main motor of a thick plate rolling mill according to claim 1, characterized in that: In the fourth step, in order to ensure the stability of the rotor (9) during the core threading process, a rear fixing rope (13) and left and right fixing ropes (12) are added to the non-load bearing end (91) of the rotor, the rear fixing rope (13) is fixed to the anchor (14) on the ground, and the left and right fixing ropes (12) are fixed to the bottom crossbeam of the gantry crane (1); the left and right fixing ropes (12) are tightened by a manual fall chain (122), the rear fixing rope (13) is first pre-tightened with a steel wire rope by the manual fall chain (122), and the steel wire rope is synchronously loosened by the manual fall chain (122) during the core threading process of the rotor (9), so as to ensure that the rotor (9) does not swing forward too much due to inertia when the gantry crane (1) is jogged.

3. A method for core threading of a main motor of a thick plate rolling mill according to claim 1, characterized in that: In the fourth step, after the adjustment of the center position of the rotor (9) is completed, and the left and right fixing cables (12) and the rear fixing cable (13) are set, the gantry crane (1) is operated to continue to move the rotor (9) toward the inner cavity of the stator (6) until the load-end bearing sling cable (92) of the rotor (9) approaches the end face of the stator (9).

4. A method for core threading of a main motor of a thick plate rolling mill according to claim 1, characterized in that: The specific steps of step six are as follows: slightly lift the screw jacks (17) at the four corners of the stator (6), pull out a pad from the fixed pad group (15), and lower the screw jacks (17) at the four corners at the same time. When the gap between the stator and rotor tops is 10 mm, stop lowering the screw jacks (17); operate the four electric fall chains on the sling to lower the rotor (9) until the gap between the rotor (9) and the lower part of the stator (6) is 10 mm; repeat the above process until the top rod of the screw jack (17) drops to the lowest position, and use a flat pad to lower the screw jack (17). , fill the gap between the fixed pad group (15) and the stator (6) bottom plate tightly with the inclined pads, pull out the pads of the lifting pad group (16) located under the screw jack (17), push out the screw jack (17) push rod, and loosen the fixed pad group (15) and the stator (6) bottom plate, repeat the above steps until all the pads are pulled out, the stator (6) is completely placed on the motor bottom plate (18), and the rotor (9) is placed on the rotor bearing seat. The core threading is now completed, and the next step is to adjust the rotor (9) and stator (6).

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