Field replacement test method for connecting device of reflecting surface and ring beam

Abstract

The invention discloses an on-site replacement test method for a connecting device of a reflecting surface and a ring beam, belongs to the technical field of maintenance of large-span spherical reflecting surfaces, and solves the technical problem of interference damage of a 2 # end shaft of a quadrilateral reflecting surface unit and a hoop gantry. The method comprises the following steps of: selecting two quadrilateral reflecting surface units which are relatively seriously damaged and are symmetrical to each other as test objects; the theoretical width and the theoretical height of the portal of the test object are preliminarily determined through analogue simulation; transforming the original hoop into a new hoop according to the theoretical width and the theoretical height; recording a motion track point of the 2 # end shaft; and if the track point is in a specified range and no interference occurs, the theoretical width and the theoretical height meet the requirements, and the original hoops are replaced by new hoops one by one. The hoop transformed according to the test result does not interfere with the 2 # end shaft, the two test units operate normally, and the size and weight of the hoop can be reduced on the premise that normal use is met, so that the installation convenience is improved, and the installation cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of maintenance of a large-span spherical reflective surface, and more specifically, to an on-site replacement test method for a reflective surface and a ring beam connection device. Background Art

[0002] The FAST active reflector is composed of 4295 triangular reflector units, 150 quadrilateral reflector units, 6670 main cables, 2225 node plates, 2225 pull-down cables and related ancillary facilities. The quadrilateral reflector units are located at the edge of the cable net. Figure 1 As shown, the quadrilateral reflector unit 2 is connected to the lower chord of the ring beam 1; the quadrilateral reflector unit 2 is a quadrilateral structure, with a total of 150 pieces of 30 types. The two 2# end shafts of the quadrilateral reflector unit 2 are placed on the original hoop 3 of the annular steel pipe of the lower chord of the ring beam 1, and the other 0# end shaft and 1# end shaft of the quadrilateral unit are respectively connected to the upper plate of the cable net node.

[0003] When the telescope is working, there is relative movement between the cable net node disks, and the 1# end axis and 2# connecting end axis of the reflector unit can slide adaptively. At present, the 2# end axis of the quadrilateral unit interferes with the gantry 4 of the original hoop 3, such as Figure 2 As shown, the height and width of the gantry 4 are insufficient. Currently, the 2# end shaft 5 of some quadrilateral units 1 has been damaged, and the 2# end shaft 5 cannot effectively contact the stainless steel plate 6 of the original clamp 3, affecting the observation accuracy and working stability of FAST. Summary of the invention

[0004] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies in the prior art. The purpose of the present invention is to provide an on-site replacement test method for a reflecting surface and a ring beam connection device, which can be used to design and transform the existing clamp gantry structure so that the 2# end shaft will not interfere with the gantry, thereby ensuring the observation accuracy and working stability of the telescope.

[0005] The technical solution of the present invention is: a field replacement test method for a reflective surface and a ring beam connection device, comprising the following steps:

[0006] Step 1. Select two quadrilateral reflective surface units that are relatively severely damaged and symmetrically located as test objects;

[0007] Step 2. Simulate the working conditions of multiple large zenith angle paraboloids, calculate the 2# end axis displacement of all quadrilateral reflective surface units in the sector where the test object is located at different paraboloids, and preliminarily determine the theoretical width and theoretical height of the gantry of the test object;

[0008] Step 3. Make a gantry structure according to the theoretical width and theoretical height, transform the original hoop into a new hoop by making the gantry structure, and replace the original hoop of the test object with the new hoop;

[0009] Step 4. Record the activity trajectory points of the 2# end shaft of the test object during the test cycle and make a test point map; at the same time, record the interference between the 2# end shaft of the test object and the new clamp;

[0010] Step 5. If the maximum displacement of the test point map is within the simulation maximum displacement range of the sector where the test object is located and no interference occurs, the theoretical width and theoretical height meet the requirements, and step 6 is executed; otherwise, the theoretical width and theoretical height are corrected according to the maximum displacement and interference of the test point map, and step 3 is executed;

[0011] Step 6. Randomly select a quadrilateral reflection surface unit as the test object;

[0012] Step 7. Replace the original clamp of the inspection object with the new clamp;

[0013] Step 8. Record the activity trajectory points of the 2# end shaft of the inspection object during the inspection cycle and make a inspection point bitmap; at the same time, record the interference between the 2# end shaft of the inspection object and the new clamp;

[0014] Step 9. If the maximum displacement of the inspection point bitmap is within the simulation maximum displacement range of the sector where the inspection object is located, and no interference occurs, the theoretical width and theoretical height are used as the product width and product height respectively, and step 10 is executed; otherwise, the theoretical width and theoretical height are corrected according to the maximum displacement and interference of the inspection point bitmap, and a new clamp is remade, and step 7 is executed;

[0015] Step 10. Make new clamps according to the product width and product height, and use the new clamps to replace the original clamps one by one.

[0016] As a further improvement, the 2# end shaft displacement includes displacement in three directions: the in-plane gantry width direction, the vertical gantry direction, and the end shaft direction.

[0017] Furthermore, the new hoop includes a hoop body, an extended steel plate is provided on the top of the pallet steel plate of the hoop body, the width of the extended steel plate is greater than the width of the pallet steel plate, a stainless steel plate is provided on the top of the extended steel plate, a portal structure is provided on the top of the stainless steel plate, the width of the extended steel plate is 400 mm and the height is 300 mm, the width of the portal structure is 350 mm, and the height of the portal structure is 260 mm.

[0018] Furthermore, the gantry structure includes L-shaped support rods respectively located on both sides of the stainless steel plate, the upper ends of the support rods on both sides are commonly connected to a cross bar, both ends of the cross bar are respectively provided with vertical rods, and observation mirrors are connected between the vertical rods at both ends. The width between the support rods on both sides is 350 mm, and the height of the cross bar is 260 mm.

[0019] Furthermore, the pallet steel plate is welded to the extended steel plate, and a first threaded section is provided at the lower end of the support rod, which passes through the stainless steel plate and the extended steel plate in turn and is locked by a double nut, and a cotter pin is provided at the first threaded section below the double nut, and a second threaded section is provided at the upper end of the support rod, and threaded holes matching the second threaded section are provided at both ends of the cross bar, and a tightening nut is provided at the second threaded section, and a first nut is provided at the vertical rod, and second nuts are provided at both sides of the observation mirror, respectively, and the first nut and the second nut are connected by a first bolt, and the stainless steel plate and the extended steel plate are connected by a second bolt.

[0020] Furthermore, a rectangular coordinate system scale line is provided on the surface of the stainless steel plate, and the origin of the rectangular coordinate system scale line is located at the center of the stainless steel plate.

[0021] Furthermore, the test period is 4 months, and the inspection period is 2 to 4 months.

[0022] Furthermore, when the original clamp is replaced with the new clamp, water stains and oil stains on the ring beam pipe wall at the clamp installation position are wiped clean.

[0023] Furthermore, when the original clamp is replaced with the new clamp, the position and angle of the new clamp on the lower chord tube of the ring beam are adjusted according to the back frame position of the quadrilateral reflecting surface unit, so that the two 2# end axes are respectively located at the center of the support plate of the new clamp when the reflecting surface is on the reference sphere.

[0024] Furthermore, the observation mirror of the new clamp is adjusted to a suitable inclination angle so that the maintenance personnel on the ring beam track can observe the overall movement of the 2# end shaft.

[0025] Beneficial Effects

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] 1. The clamp modified according to the test results of the present invention has no interference with the 2# end shaft, and the two test quadrilateral reflective surface units operate normally.

[0028] 2. The present invention determines the improved size of the clamp according to the comparison between the simulation value and the test value. Under the premise of meeting normal use, the size and weight of the clamp can be reduced, thereby improving the convenience and cost of installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a top view of the FAST reflector unit;

[0030] Figure 2 It is a schematic diagram of the interference between the 2# connection mechanism of the quadrilateral unit and the portal frame of the original clamp;

[0031] Figure 3 is a flow chart of the present invention;

[0032] Figure 4 This is a structural schematic diagram of a first embodiment of a door frame of a new clamp in the present invention;

[0033] Figure 5 This is a structural schematic diagram of a second embodiment of a door frame of a new clamp in the present invention;

[0034] Figure 6 This is a schematic diagram of the main structure of the second embodiment of the door frame of the new clamp in the present invention;

[0035] Figure 7 It is a left-side structural schematic diagram of a second embodiment of a door frame of a new clamp in the present invention;

[0036] Figure 8 It is a structural schematic diagram of the support rod of the second embodiment of the door frame in the present invention;

[0037] Fig. 9 It is a schematic diagram of the main structure of the crossbar and the vertical pole of the second embodiment of the door frame in the present invention;

[0038] Fig.10 It is a left-side structural schematic diagram of the crossbar and the vertical pole of the second embodiment of the middle frame of the present invention;

[0039] Fig.11 It is a structural schematic diagram of the observation mirror of the second embodiment of the present invention.

[0040] Fig.12 It is the test point map in the present invention.

[0041] Among them: 1-ring beam, 2-quadrilateral reflective surface unit, 3-original clamp, 4-gantry, 5-2# end shaft, 6-stainless steel plate, 7-new clamp, 8-clamp body, 9-pallet steel plate, 10-expanded steel plate, 11-stainless steel plate, 12-support rod, 13-cross bar, 14-vertical pole, 15-observation mirror, 16-first threaded segment, 17-double nut, 18-open pin, 19-second threaded segment, 20-threaded hole, 21-tightening nut, 22-first nut, 23-second nut, 24-first bolt, 25-second bolt, 26-gantry structure, 27-rectangular coordinate system scale line. DETAILED DESCRIPTION

[0042] The present invention will be further described below with reference to the specific embodiments in the accompanying drawings.

[0043] See also Figures 1 to 12 A field replacement test method for a reflective surface and a ring beam connection device comprises the following steps 1 to 10:

[0044] Step 1. Select two relatively severely damaged and symmetrically located quadrilateral reflective surface units 2 as test objects. Figure 1 As shown, relatively severely damaged and symmetrically located quadrilateral reflective surface units RA880 and RE888 are selected as test objects. Relatively severely damaged means that among the damaged quadrilateral reflective surface units, the damage is the most severe or relatively severe.

[0045] Step 2. Simulate the working conditions of multiple large zenith angle paraboloids, calculate the displacement of the 2# end axis 5 of all quadrilateral reflector units 2 in the sector where the test object is located at different paraboloids (only paraboloids can realize the FAST reflection signal to the feed cabin), and preliminarily determine the theoretical width and theoretical height of the gantry 4 of the test object. In this embodiment, the working conditions of 96 large zenith angle paraboloids are simulated, and the displacement of the 2# end axis 5 of 30 quadrilateral reflector units 2 in the sector where the test object is located at different paraboloids is calculated. The displacement of the 2# end axis 5 includes displacement in three directions: the in-plane gantry width direction, the vertical gantry direction, and the end axis direction tilting.

[0046] Step 3. Make a gantry structure 26 according to the theoretical width and theoretical height, and transform the original hoop 3 into a new hoop 7 by making the gantry structure 26, such as Figure 4 As shown, the original clamp 3 of the test object is then replaced with a new clamp 7, and the telescope performs normal observation work.

[0047] Step 4. Record the activity trajectory points of the 2# end shaft 5 of the test object during the test cycle and make a test point map, such as Fig.11 At the same time, the interference between the 2# end shaft 5 of the test object and the new clamp 7 is recorded. In this embodiment, the test period is 4 months.

[0048] Step 5. If the maximum displacement of the test point map is within the simulation maximum displacement range of the sector where the test object is located, as shown in Table 1, and no interference occurs, the theoretical width and theoretical height meet the requirements, and step 6 is performed; otherwise, the theoretical width and theoretical height are corrected according to the maximum displacement and interference of the test point map, and step 3 is performed.

[0049] Table 1

[0050]

[0051] Step 6. Randomly select a quadrilateral reflection surface unit 2 as a test object, which can be damaged or undamaged.

[0052] Step 7: Replace the original clamp 3 of the inspection object with the new clamp 7, and the telescope performs normal observation work.

[0053] Step 8. Record the moving track points of the 2# end shaft 5 of the inspection object during the inspection period and make an inspection point map; at the same time, record the interference between the 2# end shaft 5 of the inspection object and the new clamp 7. In this embodiment, the inspection period is 2 to 4 months.

[0054] Step 9. If the maximum displacement of the inspection point bitmap is within the simulated maximum displacement range of the sector where the inspection object is located, and no interference occurs, the theoretical width and theoretical height are used as the product width and product height respectively, and step 10 is executed; otherwise, the theoretical width and theoretical height are corrected according to the maximum displacement and interference of the inspection point bitmap, and a new clamp 7 is remade, and step 7 is executed.

[0055] Step 10. Make new clamps 7 according to the product width and product height, and use the new clamps 7 to replace the original clamps 3 one by one to improve the interference problem between the original clamps 3 and the 2# end shaft 5, and ensure the observation accuracy and working stability of the telescope.

[0056] In one embodiment, Figure 4 As shown, the new clamp 7 includes a clamp body 8, an extended steel plate 10 is provided on the top of the pallet steel plate 9 of the clamp body 8, the width of the extended steel plate 10 is greater than the width of the pallet steel plate 9, a stainless steel plate 11 is provided on the top of the extended steel plate 10, a portal structure 26 is provided on the top of the stainless steel plate 11, the width of the extended steel plate 10 is 400 mm and the height is 300 mm, that is, the width of the stainless steel plate 11 is 400 mm and the height is 300 mm, the width of the portal structure 26 is 350 mm, and the height of the portal structure 26 is 260 mm.

[0057] In one embodiment, Figure 5 As shown, the gantry structure 26 includes L-shaped support rods 12 located on both sides of the stainless steel plate 11, the upper ends of the support rods 12 on both sides are connected to a cross bar 13, and the two ends of the cross bar 13 are respectively provided with vertical rods 14, and an observation mirror 15 is connected between the vertical rods 14 at both ends. The width between the support rods 12 on both sides is 350mm, and the height of the cross bar 13 is 260mm. Adding the observation mirror 15 to the gantry can facilitate inspection, and the operator can directly observe whether the 2# end shaft 5 is interfered or damaged on the ring beam 1.

[0058] The pallet steel plate 9 is welded to the extended steel plate 10, the lower end of the support rod 12 is provided with a first threaded section 16, the first threaded section 16 passes through the stainless steel plate 11 and the extended steel plate 10 downwards in sequence and is locked by a double nut 17, the first threaded section 16 below the double nut 17 is provided with a split pin 18, the upper end of the support rod 12 is provided with a second threaded section 19, both ends of the cross bar 13 are provided with threaded holes 20 adapted to the second threaded section 19, the second threaded section 19 is provided with a tightening nut 21, the vertical rod 14 is provided with a first nut 22, and the two sides of the observation mirror 15 are provided with second nuts 23, the first nut 22 and the second nut 23 are connected by a first bolt 24, and the stainless steel plate 11 and the extended steel plate 10 are connected by a second bolt 25. After loosening the first bolt 24, the angle of the observation mirror 15 can be easily adjusted, and the first bolt 24 can be tightened after adjustment.

[0059] Furthermore, a rectangular coordinate system scale line 27 is provided on the surface of the stainless steel plate 11 , and the origin of the rectangular coordinate system scale line 27 is located at the center of the stainless steel plate 11 .

[0060] When replacing the original clamp 3 with the new clamp 7, wipe off the water stains and oil stains on the wall of the ring beam 1 where the clamp is installed to avoid the friction and fastening force between the clamp and the wall of the ring beam being reduced due to reasons such as wetness and slipperiness.

[0061] When replacing the original clamp 3 with the new clamp 7, adjust the position and angle of the new clamp 7 on the lower chord tube of the ring beam 1 according to the back frame position of the quadrilateral reflecting surface unit 2, so that the two 2# end shafts 5 are respectively located at the center of the support plate of the new clamp 7, that is, the center of the stainless steel plate 11 when the reflecting surface is on the reference sphere, so as to reduce the interference and damage caused by excessive offset of the 2# end shaft 5 during displacement.

[0062] Adjust the observation mirror 15 of the new clamp 7 to a suitable inclination angle so that the maintenance personnel on the horseway of the ring beam 1 can observe the overall movement of the 2# end shaft 5.

[0063] The above are only preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A field replacement test method for a reflective surface and a ring beam connection device, characterized in that: The following steps are involved: Step 1. Select two quadrilateral reflective surface units (2) that are relatively severely damaged and symmetrically located as test objects; Step 2. Simulate the working conditions of multiple large zenith angle paraboloids, calculate the displacement of the 2# end axis (5) of all quadrilateral reflection surface units (2) in the sector where the test object is located at different paraboloids, and preliminarily determine the theoretical width and theoretical height of the gantry (4) of the test object; Step 3. A portal frame structure (26) is manufactured according to the theoretical width and theoretical height, and the original clamp (3) is modified by manufacturing the portal frame structure (26) to obtain a new clamp (7), and the original clamp (3) of the test object is replaced with the new clamp (7); Step 4. Record the activity trajectory points of the 2# end shaft (5) of the test object during the test period and make a test point map; at the same time, record the interference between the 2# end shaft (5) of the test object and the new clamp (7); Step 5. If the maximum displacement of the test point map is within the simulation maximum displacement range of the sector where the test object is located and no interference occurs, the theoretical width and theoretical height meet the requirements, and step 6 is executed; otherwise, the theoretical width and theoretical height are corrected according to the maximum displacement and interference of the test point map, and step 3 is executed; Step 6. Randomly select a quadrilateral reflection surface unit (2) as a test object; Step 7. Replace the original clamp (3) of the inspection object with the new clamp (7); Step 8. Record the activity track points of the 2# end shaft (5) of the inspection object during the inspection cycle and make an inspection point bitmap; At the same time, the interference between the 2# end shaft (5) of the inspection object and the new clamp (7) is recorded; Step 9. If the maximum displacement of the inspection point bitmap is within the simulation maximum displacement range of the sector where the inspection object is located, and no interference occurs, the theoretical width and theoretical height are used as the product width and product height respectively, and step 10 is executed; otherwise, the theoretical width and theoretical height are corrected according to the maximum displacement and interference of the inspection point bitmap, and a new clamp (7) is remade, and step 7 is executed; Step 10. Make new clamps (7) according to the product width and product height, and use the new clamps (7) to replace the original clamps (3) one by one.

2. The on-site replacement test method for the reflective surface and ring beam connection device according to claim 1, characterized in that: The displacement of the 2# end shaft (5) includes displacement in three directions: the in-plane portal width direction, the vertical portal direction, and the end shaft direction.

3. The on-site replacement test method for the reflective surface and ring beam connection device according to claim 1, characterized in that: The new clamp (7) comprises a clamp body (8), an extended steel plate (10) is provided on the top of the pallet steel plate (9) of the clamp body (8), the width of the extended steel plate (10) is greater than the width of the pallet steel plate (9), a stainless steel plate (11) is provided on the top of the extended steel plate (10), a portal structure (26) is provided on the top of the stainless steel plate (11), the width of the extended steel plate (10) is 400 mm and the height is 300 mm, the width of the portal structure (26) is 350 mm, and the height of the portal structure (26) is 260 mm.

4. The on-site replacement test method for the reflective surface and ring beam connection device according to claim 3, characterized in that: The gantry structure (26) includes L-shaped support rods (12) respectively located on both sides of the stainless steel plate (11), the upper ends of the support rods (12) on both sides are commonly connected to a cross bar (13), the two ends of the cross bar (13) are respectively provided with vertical rods (14), and an observation mirror (15) is connected between the vertical rods (14) at both ends. The width between the support rods (12) on both sides is 350 mm, and the height of the cross bar (13) is 260 mm.

5. The on-site replacement test method for the reflective surface and ring beam connection device according to claim 4, characterized in that: The tray steel plate (9) is welded to the extended steel plate (10), and a first threaded section (16) is provided at the lower end of the support rod (12), and the first threaded section (16) passes through the stainless steel plate (11) and the extended steel plate (10) in sequence downward and is locked by a double nut (17), and a cotter pin (18) is provided at the first threaded section (16) below the double nut (17), and a second threaded section (19) is provided at the upper end of the support rod (12), and threaded holes (20) matching the second threaded section (19) are provided at both ends of the cross bar (13), and the second threaded section (19) is provided with a tightening nut (21), and the vertical rod (14) is provided with a first nut (22), and second nuts (23) are provided on both sides of the observation mirror (15), and the first nut (22) and the second nut (23) are connected by a first bolt (24), and the stainless steel plate (11) and the extended steel plate (10) are connected by a second bolt (25).

6. The on-site replacement test method for the reflective surface and ring beam connection device according to claim 3, characterized in that: The surface of the stainless steel plate (11) is provided with rectangular coordinate scale lines (27), and the origin of the rectangular coordinate scale lines (27) is located at the center of the stainless steel plate (11).

7. The on-site replacement test method for the reflective surface and ring beam connection device according to claim 1, characterized in that: The test period is 4 months, and the inspection period is 2 to 4 months.

8. The on-site replacement test method for the reflective surface and ring beam connection device according to claim 1, characterized in that: When the original clamp (3) is replaced by the new clamp (7), water stains and oil stains on the pipe wall of the ring beam (1) at the clamp installation position are wiped clean.

9. The on-site replacement test method for the reflective surface and ring beam connection device according to claim 1, characterized in that: When the original clamp (3) is replaced by the new clamp (7), the position and angle of the new clamp (7) on the lower chord tube of the ring beam (1) are adjusted according to the back frame position of the quadrilateral reflection surface unit (2), so that the two 2# end shafts (5) are respectively located at the center of the support plate of the new clamp (7) when the reflection surface is on the reference sphere.

10. The on-site replacement test method of the reflective surface and ring beam connection device according to claim 4, characterized in that: The observation mirror (15) of the new hoop (7) is adjusted to a suitable inclination angle so that the maintenance personnel on the horseway of the ring beam (1) can observe the overall movement of the 2# end shaft (5).

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