A foundation bolt nut screwing device and construction method in a closed space

Abstract

The application discloses a bolt nut screwing device in a closed space and a construction method, and belongs to the technical field of construction machinery. The bolt nut screwing device comprises a top cross screwing arm, a bottom cross screwing arm, winding frames, an upper driving rope and a lower driving rope. The top cross screwing arm and the bottom cross screwing arm are oppositely arranged in an up-down mode, and the top cross screwing arm and the bottom cross screwing arm are welded through the winding frames. The upper driving rope is wound on the upper part of the four winding frames, and the lower driving rope is wound on the lower part of the four winding frames. A pin shaft is arranged at the top center of the top cross screwing arm, and the pin shaft is rotationally connected with an adjusting rod. The four arms of the bottom cross screwing arm are connected with an upper gasket through pegs. A nut is fixed at the bottom center of the bottom cross screwing arm. The bottom cross screwing arm center and the upper gasket are both provided with through holes for the bolt to pass through. In the application, the bolt is fixed at the center of the steel pipe column foot, and the whole fixing process does not need additional welding, is completely mechanical fixing, and does not cause any influence on the steel pipe column itself.

Description

Technical Field

[0001] This invention relates to the field of prefabricated steel structures, and in particular to a device and construction method for tightening anchor bolts and nuts in an enclosed space. Background Technology

[0002] Prefabricated steel structures can significantly shorten the construction cycle of buildings and structures. With the introduction of relevant policies on prefabricated buildings by governments at all levels, prefabricated steel structure buildings and structures have developed rapidly. Among them, the type of key nodes of prefabricated steel structure buildings and structures plays an important role in the steel structure installation process. Under the primary premise of meeting safety requirements, it affects both the external aesthetics and the rationality of stress distribution.

[0003] Currently, in the case of rigidly connected steel column bases, anchor bolts are typically placed on the outer perimeter of the steel column to increase the modulus of the column base. In the case of hinged steel column bases, anchor bolts are usually placed on the inner side of the outer frame of the steel column to reduce the modulus of the column base. However, this approach only applies to steel columns with "H" or "I" shaped cross-sections, specifically placing the anchor bolts on both sides of the web, within the flange width. However, in the arrangement of anchor bolts for circular or rectangular cross-section columns, anchor bolts can usually only be placed on the outer perimeter of the steel column, and they need to be symmetrically arranged with a large spacing. The line connecting the center points of two relatively symmetrical bolts is perpendicular to the plane containing the principal bending moment. This arrangement can only guarantee the hinged load requirements in one direction, but cannot meet the hinged load requirements in other directions. This is because most structures need to consider bending moments in multiple dimensions of space, not just bending moments in a single two-dimensional plane. Therefore, how to reduce the modulus of rotation in all directions of steel pipe columns with hinged column bases is an urgent problem to be solved. Ideally, only one anchor bolt should be installed at the center of the column base. However, a steel pipe column is a closed space, and if the anchor bolt is installed at the center of the column base, how to tighten the nut on the anchor bolt becomes a key issue. Currently, one method is to open a large hole in the side wall, which allows a wrench to be inserted to tighten the bolt. After tightening, the hole is sealed with a steel plate, which is welded to the steel column. Because the hole is large, if it is not sealed with a steel plate, it will seriously affect the stress stability of the column. If it is sealed, the high temperature of the welding process will generate large residual stress at the weld, causing micro-deformation of the column. This is not acceptable for buildings and structures with high precision requirements, especially for equipment platforms such as precision instruments. Therefore, this method is only suitable for buildings and structures with low error requirements. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects of the prior art by providing a device and construction method for tightening anchor bolts and nuts in an enclosed space.

[0005] The objective of this invention can be achieved through the following technical solutions: In a first aspect, the present invention provides a bolt and nut tightening device for an enclosed space, comprising a top cross tightening arm, a bottom cross tightening arm, a winding frame, an upper drive rope, and a lower drive rope; The top and bottom cross-shaped rotating arms are arranged vertically opposite each other, and are welded together by four winding frames. The upper drive rope is wound on the upper part and the lower drive rope is wound on the lower part of the four winding frames. A pin is set at the top center of the top cross-shaped rotating arm, and the pin is rotatably connected to the adjusting rod. The four arms of the bottom cross-shaped rotating arm are connected to the upper washer by studs. A nut is fixed at the bottom center of the bottom cross-shaped rotating arm. Through holes for anchor bolts are opened at the center of the bottom cross-shaped rotating arm and the upper washer.

[0006] As a further technical solution, a limiting plate is welded to the outside of each winding frame, so that the upper drive rope and the lower drive rope are set independently and do not interfere with each other.

[0007] As a further technical solution, the bottom cross-shaped screw arm has an opening in each of its four directions, allowing the stud to pass through the opening.

[0008] As a further technical solution, there is a pair of bolt slots below the bottom cross-shaped screw arm for fixing the nut. The bolt slots are welded to the bottom of the bottom cross-shaped screw arm.

[0009] As a further technical solution, a stud limiting sleeve is welded below the bottom cross-shaped screw-tightening arm. The central axis of the stud limiting sleeve coincides with the center of the four stud openings and is welded and fixed to the bottom of the bottom cross-shaped screw-tightening arm. The height of the stud limiting sleeve must be less than the difference between the length of the thin straight section of the stud and the thickness of the bottom cross-shaped screw-tightening arm, and the length of the thin straight section of the stud must be greater than the sum of the height of the nut and the thickness of the bottom cross-shaped screw-tightening arm.

[0010] As a further technical solution, the lower end of the stud is welded to the upper part of the upper washer for fixation.

[0011] As a further technical solution, two symmetrical winding frames serve as fixing frames for one end of the upper drive rope and the lower drive rope, respectively, and the other end of the upper drive rope and the lower drive rope are each connected to an end pull rod.

[0012] Secondly, based on the aforementioned anchor bolt and nut tightening device within an enclosed space, the present invention also provides a construction method, as follows: Step 1: Place the screwing device at the bottom of the steel pipe, and simultaneously pass the adjusting rod through the adjusting rod opening on the steel pipe wall; then pass the upper drive rope and the lower drive rope through the stop rod openings on both sides of the steel pipe wall and connect them to the end tie rods, while passing the stop rods through the two stop rod openings and bending both ends; finally, weld the base plate firmly to the steel pipe to form a round steel column. Step 2: Cut off the bend at one end of the stop bar and remove the stop bar; Step 3: Place the round steel column on the adjusting nut and lower washer of the anchor bolt. Then, lift the tightening device to the top of the anchor bolt using the adjusting rod. Shake the device to align the upper washer and the hole of the nut with the top of the anchor bolt and straighten the tightening device. At the same time, pull the end rods on both sides to start rotating the tightening device until the end rods can no longer be pulled. Shake the adjusting rod to transmit the signal to the tightening device to further assess and judge the tightness of the tightening device. After tightening the nut, the upper washer will also be fixed. Step 4: Fill the gap between the short column and the base plate with grout or non-shrink fine aggregate concrete, and then add grout into the round steel column at the opening of the retaining rod. When the grout covers the bottom cross-shaped screw arm, the construction and installation of the column base is completed.

[0013] Step 5: Cut off the exposed parts of the end tie rod and adjusting rod, and seal the openings of the adjusting rod and the stop rod with structural sealant to prevent oxidation and corrosion of the inner surface of the steel pipe column.

[0014] As a further technical solution, shear keys can also be welded to the bottom of the base plate.

[0015] The beneficial effects of this invention are as follows: This invention utilizes a designed anchor bolt tightening device to fix anchor bolts at the center of the steel pipe column base. Since the entire fixing process requires no additional welding and is entirely mechanical, it does not affect the steel pipe column itself. Furthermore, the anchor bolt tightening device can be pre-connected to the circular cross-section steel pipe column and base plate at the factory. Once on-site, it can be integrated with other devices, saving time and effort. During on-site installation, the entire device can be connected simply by pulling the end rods on both sides. Finally, the gap between the short column and the base plate is filled with grout or non-shrink fine aggregate concrete. Then, grout is injected into the circular steel column through the opening in the retaining rod using a grouting gun. The grout prevents the nuts from loosening and further enhances the bending stiffness of the base plate. Attached Figure Description

[0016] Figure 1 This is a top-down overall disassembly diagram of a circular cross-section steel pipe column with a hinged column base, including the foundation, anchor bolts, tightening device, and end plate.

[0017] Figure 2 This is an overall elevation view of a circular cross-section steel pipe column with hinged column base, assembled with foundation, anchor bolts, tightening devices, end plates, etc.

[0018] Figure 3 A perspective view of the column base with an anchor bolt tightening device in an enclosed space; Figure 4 A front view of the anchor bolt tightening device in an enclosed space; Figure 5 A side view of the anchor bolt tightening device in an enclosed space; Figure 6 A three-dimensional diagram of an anchor bolt tightening device in an enclosed space; Figure 7 A schematic diagram of the cross-shaped screw-in arm and nuts at the bottom of the anchor bolt tightening device in an enclosed space; Figure 8 Diagram of the stud limiting sleeve; Figure 9 Diagram of a stud; Figure 10 The top cross-shaped screw-on arm of the screw-on device; Figure 11 For adjusting rod and pin; Figure 12 For winding frames of steel wire rope or chemical fiber rope; Figure 13 A wire rope or chemical fiber rope winding frame with fixing holes; Figure 14 As soon as the circular cross-section steel column is in place, the screwing device is adjusted to the position of the anchor bolt.

[0019] Figure 15 This refers to the state after the screwing device tightens the nut, and after grouting material is added inside the column base, and grouting material or non-shrink fine aggregate concrete is filled between the column base plate and the short column.

[0020] In the diagram: 1. Top cross-shaped screwing arm; 2. Bottom cross-shaped screwing arm; 3. Wire rope or chemical fiber rope winding frame; 4. Wire rope or chemical fiber rope limiting plate; 5. Upper wire rope or chemical fiber rope; 6. Lower wire rope or chemical fiber rope; 7. Stud limiting sleeve; 8. Nut; 9. Upper washer; 10. Stop bar; 11. Adjusting rod; 12. Pin; 13. Bolt slot; 14. Stud; 15. Wire rope or chemical fiber rope end pull rod; 16. Grouting material; 17. Stop bar opening; 18. Adjusting rod opening; 100. Tightening device; 200. Round steel pipe column; 300. Column base plate; 400. Lower shim; 500. Adjusting nut; 600. Anchor bolt; 700. Foundation short column; 800. Grouting material or non-shrink fine aggregate concrete; 900. Round steel column with selection device. Detailed Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0022] To address the technical problems existing in the prior art, this embodiment discloses an anchor bolt nut tightening device in an enclosed space, including a top cross tightening arm, a bottom cross tightening arm, a winding frame, an upper drive rope, and a lower drive rope. The top and bottom cross tightening arms are arranged vertically opposite each other, and are welded together by four winding frames. The drive rope is wound on the upper part of the four winding frames, and the lower drive rope is wound on the lower part. A pin is provided at the top center of the top of the top cross tightening arm, and the pin is rotatably connected to an adjusting rod. The four arms of the bottom cross tightening arm are connected to an upper washer by studs. A nut is fixed at the bottom center of the bottom cross tightening arm. Through holes for anchor bolts to pass through are provided at the center of the bottom cross tightening arm and on the upper washer. This invention utilizes a designed anchor bolt tightening device to fix anchor bolts at the center of the steel pipe column base. Since the entire fixing process requires no additional welding and is entirely mechanical, it does not affect the steel pipe column itself. Furthermore, the anchor bolt tightening device can be pre-connected to the circular cross-section steel pipe column and base plate at the factory. Once on-site, it can be integrated with other devices, saving time and effort. During on-site installation, the entire device can be connected simply by pulling the end rods on both sides. Finally, the gap between the short column and the base plate is filled with grout or non-shrink fine aggregate concrete. Then, grout is injected into the circular steel column through the opening in the retaining rod using a grouting gun. The grout prevents the nuts from loosening and further enhances the bending stiffness of the base plate.

[0023] Furthermore, in this embodiment, the upper drive rope is an upper steel wire rope or a chemical fiber rope 5; the lower drive rope is a lower steel wire rope or a chemical fiber rope 6. The following description uses these two types of rope as examples.

[0024] like Figures 1-15 As shown, the anchor bolt and nut tightening device 100 disclosed in this embodiment for an enclosed space consists of a top cross-shaped tightening arm 1; a bottom cross-shaped tightening arm 2; a wire rope or chemical fiber rope winding frame 3; a wire rope or chemical fiber rope limiting plate 4; an upper wire rope or chemical fiber rope 5; a lower wire rope or chemical fiber rope 6; a stud limiting sleeve 7; a nut 8; an upper washer 9; a stop bar 10; an adjusting rod 11; a pin 12; a bolt groove 13; a stud 14; and a wire rope or chemical fiber rope end pull rod 15. The top cross-shaped twisting arm 1 and the bottom cross-shaped twisting arm 2 are arranged vertically opposite each other. There are four wire rope or chemical fiber rope winding frames 3, which are independently set up and connected to the four arms of the top cross-shaped twisting arm 1 and the bottom cross-shaped twisting arm 2 respectively. The top of the wire rope or chemical fiber rope winding frame 3 is welded to the top cross-shaped twisting arm 1, and the bottom is welded to the bottom cross-shaped twisting arm 2, forming a whole. The upper wire rope or chemical fiber rope 5 is wound on the upper part of the four wire rope or chemical fiber rope winding frames 3, and the lower wire rope or chemical fiber rope 6 is wound on the lower part. A wire rope or chemical fiber rope limiting plate 4 is welded on the outside of each wire rope or chemical fiber rope winding frame 3, so that the upper wire rope or chemical fiber rope 5 and the lower wire rope or chemical fiber rope 6 are independently set up.

[0025] Furthermore, such as Figure 10 , Figure 11 As shown, a pin 12 is provided at the top center of the top cross-shaped rotating arm 1. The pin 12 is rotatably connected to the adjusting rod 11, which is used to adjust the height of the entire device.

[0026] Furthermore, the four arms of the bottom cross-screw arm 2 are connected by studs 14 (studs 14 are as follows) Figure 9 (As shown) is connected to the upper washer 9, and at the center of the bottom cross-shaped screw arm 2 through which the anchor bolt passes, a bolt slot 13 is welded on the outside of the bottom center position of the bottom cross-shaped screw arm 2. A nut 8 is fixedly installed in the bolt slot 13, and the nut 8 is threadedly engaged with the anchor bolt; the anchor bolt passes through the through hole in the center of the upper washer 9 and is threadedly engaged with the nut 8. The specific manufacturing method of the above components is as follows: First, fabricate the top cross-shaped screw-on arm 1 and the bottom cross-shaped screw-on arm 2. The bottom cross-shaped screw-on arm 2 has an opening in each of its four directions for the stud 14 to pass through. The diameter of the stud hole must be larger than the diameter of the thin, straight section of the stud 14, but smaller than the diameter of the stud head. The bottom cross-shaped screw-on arm 2 has a larger opening in the middle, the diameter of which must be larger than the nominal diameter of the anchor bolt, for the anchor bolt to pass through. Below the bottom cross-shaped screw-on arm 2, there is a pair of bolt slots 13 for fixing the nut 8. The bolt slots 13 are welded to the bottom of the bottom cross-shaped screw-on arm 2. (See [reference]). Figure 7 .

[0027] Below the bottom cross-shaped screw-twisting arm 2 are four pairs of stud limit sleeves 7 (the structure of the paired stud limit sleeves 7 is as follows). Figure 8As shown), the central axis of the stud limiting sleeve 7 coincides with the center of the four stud openings and is welded to the bottom of the bottom cross-shaped screw-tightening arm 2. The height of the stud limiting sleeve 7 must be less than the difference between the length of the thin straight section of the stud 14 and the thickness of the bottom cross-shaped screw-tightening arm 2, and the length of the thin straight section of the stud 14 must be greater than the sum of the height of the nut 8 and the thickness of the bottom cross-shaped screw-tightening arm 2. A selection device has four studs 14. The lower end of the stud 14 is welded to the upper part of the upper washer 9; the studs 14 are not welded to the bottom cross-shaped screw-tightening arm 2, allowing for limited movement between them. For details, please refer to [reference needed]. Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 ; like Figure 12 , Figure 13 As shown, in this embodiment, the wire rope or chemical fiber rope winding frame 3 is a steel plate, and a wire rope or chemical fiber rope limiting plate 4 is welded to the outside of the steel plate; the upper end of the wire rope or chemical fiber rope winding frame 3 is welded and fixed to the top cross-twisting arm 1, and the lower end of the wire rope or chemical fiber rope winding frame 3 is welded and fixed to the bottom cross-twisting arm 2. The top cross-twisting arm 1, the bottom cross-twisting arm 2, and the wire rope or chemical fiber rope winding frame 3 all need a certain bending stiffness; the upper wire rope or chemical fiber rope 5 and the lower wire rope or chemical fiber rope 6 are wound and fixed on the wire rope or chemical fiber rope winding frame 3 in opposite directions. The specific winding method can be varied, as long as it can achieve the goal of rotating the wire rope or chemical fiber rope winding frame 3 by dragging the upper wire rope or chemical fiber rope 5 and the lower wire rope or chemical fiber rope 6. Furthermore, the upper wire rope or chemical fiber rope 5 and the lower wire rope or chemical fiber rope 6 are separated by a wire rope or chemical fiber rope limiting plate 4, making them independent of each other. There are two symmetrical wire rope or chemical fiber rope winding frames 3, which serve as fixing frames for one end of the upper wire rope or chemical fiber rope 5 and the lower wire rope or chemical fiber rope 6, respectively. That is, one end of the upper wire rope or chemical fiber rope 5 is fixed on the first wire rope or chemical fiber rope winding frame, and one end of the lower wire rope or chemical fiber rope 6 is fixed on the second wire rope or chemical fiber rope winding frame. The first wire rope or chemical fiber rope winding frame and the second wire rope or chemical fiber rope winding frame are symmetrically arranged. The other end of the upper wire rope or chemical fiber rope 5 passes through the stop bar opening 17 on the left side of the steel pipe 200 and connects to the left end tie rod 15 of the wire rope or chemical fiber rope. The other end of the lower wire rope or chemical fiber rope 6 passes through the stop bar opening 17 on the right side of the steel pipe 200 and connects to the right end tie rod 15 of the wire rope or chemical fiber rope. (See also...) Figure 5Preferably, the left and right stop openings 17 are symmetrically arranged with respect to the axis of the steel pipe 200, so that the upper wire rope or chemical fiber rope 5 is tangent to the wire rope or chemical fiber rope winding frame 3, and the lower wire rope or chemical fiber rope 6 is also tangent to the wire rope or chemical fiber rope winding frame 3. Then, by simultaneously dragging the upper wire rope or chemical fiber rope 5 and the lower wire rope or chemical fiber rope 6 clockwise or counterclockwise, the wire rope or chemical fiber rope winding frame 3 can be rotated.

[0028] Furthermore, the lengths of both the upper wire rope or chemical fiber rope 5 and the lower wire rope or chemical fiber rope 6 must be sufficient to ensure that the nut 8 can be rotated and tightened.

[0029] Furthermore, such as Figure 2 As shown, the top cross-shaped rotating arm 1 has an opening in the middle, the size of which matches the pin 12. The adjusting rod 11 is connected to the pin 12 via a pull ring. See [reference needed]. Figure 11 .

[0030] The specific construction methods are as follows: First, prepare the screwing device and place it at the bottom of the steel pipe 200. Simultaneously, pass the adjusting rod 11 through the adjusting rod opening 18 in the wall of the steel pipe 200. Then, pass the upper steel wire rope or chemical fiber rope 5 and the lower steel wire rope or chemical fiber rope 6 through the stop rod openings 17 on both sides of the wall of the steel pipe 200 and connect them to the end pull rod 15. At the same time, pass the stop rod 10 through the stop rod opening 17 and bend both ends. Finally, weld the base plate 300 firmly to the steel pipe 200 to form the circular steel column 900. Figure 4 , Figure 5 As shown; Second, cut off the bend at one end of the stop bar 10 and remove the stop bar 10; Third, the circular steel column 900, consisting of the screwing device 100, the circular cross-section steel pipe column 200, and the base plate 300, is placed on the adjusting nut 500 and the lower washer 400 on the anchor bolt. Then, the screwing device 100 is raised to the top of the anchor bolt 600 via the adjusting rod 11 (see...). Figure 14 By shaking, the holes of the upper washer 9 and nut 8 are brought into contact with the top of the anchor bolt 600, and the tightening device 100 is straightened. At the same time, the end rods 15 of the steel wire rope or chemical fiber rope on both sides are pulled, and the tightening device 100 starts to rotate until the end rods 15 of the steel wire rope or chemical fiber rope can no longer be pulled. The adjustment rod is shaken to transmit the signal to the tightening device to further evaluate and judge the tightness of the tightening device.

[0031] If the tightening process is hindered by defects in the threads caused by quality problems with the anchor bolts, the adjusting rod can be shaken to reduce resistance and overcome the defective section of the anchor bolt.

[0032] After tightening nut 8, upper washer 9 is also fixed.

[0033] Fourth, after tightening nut 8, the gap between short column 700 and base plate 300 needs to be filled with grout or non-shrink fine aggregate concrete 800. Then, use a grouting gun to inject grout 16 into the round steel column 900 through the stop bar opening 17. Grout 16 is self-leveling. When the grout 16 covers the bottom cross-shaped screw arm 2, the column base construction and installation are complete. Grout 16 can prevent nut 8 from loosening and enhance the bending stiffness of base plate 300.

[0034] Fifth, after all the above procedures are completed, cut off the exposed portions of the steel wire rope or chemical fiber rope end pull rod 15 and adjusting rod 11. Seal the adjusting rod opening 18 and the stop rod opening 17 with structural sealant to prevent oxidation and corrosion of the inner surface of the steel pipe column 900. See the final attached diagram. Figure 15 , Figure 1 , Figure 2 , Figure 3 ; This invention does not affect the arrangement of shear keys in the column base plate, and shear keys can be welded at the bottom of the base plate 300 as needed.

[0035] In steel structure buildings where the column base is designed as a hinged connection, this device can be used for the base connection of columns under compression or columns with small pull-out forces. It is aesthetically pleasing, occupies little space, and has reasonable stress distribution.

[0036] In addition, in the lattice steel pipe tower structure of ultra-high voltage overhead transmission lines in the power industry, this device can also be used to treat the base connection of the column foot of the straight tower and the column foot connection of the pressure column of the tension tower, provided that the calculation is satisfied. This makes the connection more aesthetically pleasing and the stress distribution more reasonable.

Claims

1. A device for tightening anchor bolts and nuts in an enclosed space, characterized in that, Includes a top cross-twisting arm, a bottom cross-twisting arm, a winding frame, an upper drive rope, and a lower drive rope; The top cross-shaped rotating arm and the bottom cross-shaped rotating arm are arranged vertically opposite each other, and the top cross-shaped rotating arm and the bottom cross-shaped rotating arm are welded together by four winding frames; the upper drive rope is wound on the upper part of the four winding frames and the lower drive rope is wound on the lower part; a pin is set at the top center of the top cross-shaped rotating arm, and the pin is rotatably connected to the adjusting rod; the four arms of the bottom cross-shaped rotating arm are connected to the upper washer by studs; a nut is fixed at the bottom center of the bottom cross-shaped rotating arm; through holes for anchor bolts to pass through are opened at the center of the bottom cross-shaped rotating arm and the upper washer. Below the bottom cross-shaped screw arm, there is a pair of bolt slots for fixing nuts. The bolt slots are welded to the bottom of the bottom cross-shaped screw arm. A stud limiting sleeve is also welded below the bottom cross-shaped screw-twisting arm. The central axis of the stud limiting sleeve coincides with the center of the corresponding stud hole and is welded and fixed to the bottom of the bottom cross-shaped screw-twisting arm. The height of the stud limiting sleeve is less than the difference between the length of the thin straight section of the stud and the thickness of the bottom cross-shaped screwing arm, and the length of the thin straight section of the stud is greater than the sum of the height of the nut and the thickness of the bottom cross-shaped screwing arm.

2. The anchor bolt and nut tightening device in an enclosed space as described in claim 1, characterized in that, A limiting plate is welded to the outside of each winding frame, so that the upper drive rope and the lower drive rope are set independently.

3. The anchor bolt and nut tightening device in an enclosed space as described in claim 1, characterized in that, The bottom cross-shaped screw arm has an opening in each of its four directions, through which the stud passes.

4. The anchor bolt and nut tightening device in an enclosed space as described in claim 1, characterized in that, The lower end of the stud is welded to the upper part of the upper washer for fixation.

5. The anchor bolt and nut tightening device in an enclosed space as described in claim 1, characterized in that, Two symmetrical winding frames serve as fixing frames for one end of the upper and lower drive ropes, respectively, and the other end of the upper and lower drive ropes are each connected to an end pull rod.

6. A construction method for fixing anchor bolts using the anchor bolt and nut tightening device in an enclosed space as described in any one of claims 1-5, characterized in that, as follows: Step 1: Place the screwing device at the bottom of the steel pipe, and simultaneously pass the adjusting rod through the adjusting rod opening in the steel pipe wall; then pass the upper drive rope and the lower drive rope through the stop rod openings on both sides of the steel pipe wall and connect them to the end tie rods, while passing the stop rods through the two stop rod openings and bending the two ends of the stop rods; finally, weld the base plate firmly to the steel pipe to form a round steel column. Step 2: Cut off the bend at one end of the stop bar and remove the stop bar; Step 3: Place the round steel column on the adjusting nut and lower washer of the anchor bolt. Then, lift the tightening device to the top of the anchor bolt using the adjusting rod. Shake the device to align the upper washer and the hole of the nut with the top of the anchor bolt and straighten the tightening device. At the same time, pull the end rods on both sides to start rotating the tightening device until the end rods can no longer be pulled. Shake the adjusting rod to transmit the signal to the tightening device to further assess and judge the tightness of the tightening device. After tightening the nut, the upper washer will also be fixed. Step 4: Fill the gap between the short column and the base plate with grout or non-shrink fine aggregate concrete, and then add grout into the round steel column at the opening of the retaining rod. When the grout covers the bottom cross-shaped screw arm, the construction and installation of the column base is completed. Step 5: Cut off the exposed parts of the end tie rod and adjusting rod, and seal the openings of the adjusting rod and the stop rod with structural sealant to prevent oxidation and corrosion of the inner surface of the steel pipe column.

7. The construction method as described in claim 6, characterized in that, Shear keys can also be welded to the bottom of the base plate.

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