Anti-deformation threaded steel pipe supporting structure
The design of the anti-deformation support mechanism solves the shortcomings of threaded steel pipe support structures in terms of height adjustment and anti-deformation, achieving rapid installation and efficient protection, and improving the service life and safety of threaded steel pipes.
Patent Information
- Application Number
- CN202520847601.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-30
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2035-04-30
AI Technical Summary
Existing threaded steel pipe support structures cannot quickly adjust the support height according to changes in ground height, resulting in low installation efficiency, poor flexibility, and difficulty in protecting thin-walled threaded steel pipes. They are also prone to deformation and damage due to external forces, reducing service life and safety.
The anti-deformation support mechanism includes a T-shaped support base, a two-way screw, a movable plate, an adjustable support rod, a concave block, a connecting rod, and first and second arc-shaped clamps. The support height is adjusted by a knob, and rubber pads and reinforcing ribs are installed inside the clamps to provide elastic cushioning and strength support.
It enables rapid horizontal laying and height adjustment of threaded steel pipes, improves installation efficiency and structural flexibility, enhances the deformation resistance of threaded steel pipes, extends service life and improves safety.
Smart Images

Figure CN223924093U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a support structure field especially relates to a threaded steel pipe support structure of preventing deformation. BACKGROUND
[0002] Threaded steel pipe is a kind of steel pipe with spiral thread on the surface, and its thread can be external thread, internal thread or both. This unique thread structure gives threaded steel pipe unique performance in connection and fluid transportation. For example, by adjusting the parameters of thread (such as pitch, thread depth, etc.), the precise control of fluid flow rate can be realized. In addition, threaded steel pipe is usually made of high-quality carbon steel or alloy steel as raw material, and is made through a series of precise production processes, such as raw material preparation, forming, welding, testing, etc., to ensure its high strength, corrosion resistance and good connection performance. Threaded steel pipe is widely used in petroleum, natural gas, chemical industry, power and other fields.
[0003] In the prior art, the installation environment of threaded steel pipe is often complex and changeable, such as underground, elevated or underwater, etc. In these environments, the support structure can ensure the correct installation and positioning of the pipeline, prevent the pipeline damage or leakage problem caused by improper installation. However, the structure and function of the existing support structure are relatively single, only have the function of supporting the threaded steel pipe, and it is difficult to adjust the installation support height of the threaded steel pipe according to the height change of the ground, which leads to the problem that the rapid horizontal laying of the threaded steel pipe cannot be ensured, thereby not only reducing the installation efficiency of the threaded steel pipe, but also reducing the use flexibility and practicability of the support structure, and at the same time, it is difficult to effectively protect the thin-walled threaded steel pipe, which leads to the problem that the thin-walled threaded steel pipe is easy to deform and damage when subjected to external impact, extrusion or bending force, thereby not only shortening the service life of the threaded steel pipe, but also reducing the use safety of the threaded steel pipe. SUMMARY
[0004] The main purpose of the utility model is to provide a threaded steel pipe support structure which can effectively solve the problems in the background art.
[0005] To achieve the above-mentioned purpose, the technical scheme adopted by the utility model is as follows:
[0006] The utility model provides a kind of anti-deformation threaded steel pipe support structure, including threaded steel pipe body, the outside of the threaded steel pipe body is equipped with several anti-deformation support mechanisms, and anti-deformation support mechanism includes T-shaped support seat, bidirectional screw rod, movable plate, adjusting support rod, concave block, connecting rod, first arc clamp and second arc clamp, the bidirectional screw rod is movably connected in the top surface of the horizontal part of T-shaped support seat by the first rotating rod of two ends, and adjusting support rod is movably connected in the top surface of the vertical part of T-shaped support seat, two movable plates are movably connected with bidirectional screw rod by screw hole on side wall respectively, and the top surface of movable plate and the bottom of the two side walls of adjusting support rod are fixedly connected with concave block respectively, the connecting rod is movably connected between concave block by the second rotating rod of two ends, the first arc clamp is fixedly connected at the top of adjusting support rod, and the second arc clamp is fixedly connected with first arc clamp by first nut, and the first arc clamp and the second arc clamp between adjacent are also fixedly connected with several reinforcing rib plates by second nut.
[0007] Further, the top surface of the horizontal part of the T-shaped support seat is provided with a horizontal port, and the inside of the horizontal port is provided with a first rotating hole on the left and right two end walls respectively, the top surface of the vertical part of the T-shaped support seat is provided with a vertical port, and the inside of the vertical port is provided with a side port on the left and right two side walls respectively.
[0008] Further, the left and right two ends of the bidirectional screw rod are fixedly installed with first rotating rods respectively, and the first rotating rods are movably installed in the first rotating holes, the outside end of the right first rotating rod is further fixedly installed with a knob, the side wall of the movable plate is provided with a screw hole and is threadedly connected with the bidirectional screw rod through the screw hole, the adjusting support rod is inserted and installed in the vertical port, and the left and right two side wall bottom ends of the adjusting support rod and the top surface of the movable plate are fixedly installed with concave blocks respectively, the two ends of the inner wall of the concave block are provided with second rotating holes respectively, the left and right two ends of the connecting rod are fixedly installed with a group of symmetrical second rotating rods respectively, and the second rotating rods are movably installed in the second rotating holes.
[0009] Further, the first arc clamp is fixedly installed at the top of the adjusting support rod, and the inner walls of the first arc clamp and the second arc clamp are fixedly installed with arc-shaped first rubber pads respectively, the left and right two sides of the second arc clamp are fixedly installed with fixed blocks respectively, and the bottom surface of the fixed block is fixedly installed with a first threaded short rod, the left and right two sides of the first arc clamp are fixedly installed with connecting blocks respectively, and the top surface of the connecting block is provided with a first mounting hole, the first threaded short rod is inserted and installed in the first mounting hole, and the first nut is threadedly connected with the first threaded short rod.
[0010] Further, the outer walls of the first arc clamp and the second arc clamp are further fixedly installed with several groups of symmetrical second threaded short rods in the form of annular array.
[0011] Further, the inner wall of the reinforcing rib plate is fixedly provided with a second rubber plate, and the outer wall of the reinforcing rib plate is provided with a second mounting hole on each side, the second threaded short rod is inserted into the second mounting hole, and the second nut is screwed together with the second threaded short rod.
[0012] Compared with the prior art, the anti-deformation supporting mechanism has the following beneficial effects:
[0013] In the utility model, the threaded steel pipe body is fixed between the first arc-shaped clamp and the second arc-shaped clamp after the second arc-shaped clamp is combined and fixed with the first arc-shaped clamp through the first rubber pad, and the threaded steel pipe body can be elastically buffered and damped by the first rubber pad installed in the first arc-shaped clamp and the second arc-shaped clamp, thereby preventing the threaded steel pipe body from deforming due to vibration;
[0014] The second rubber plate is tightly attached to the outer wall of the threaded steel pipe body, the reinforcing rib layer is formed on the threaded steel pipe body by wrapping the threaded steel pipe body with the reinforcing rib plates, the strength of the threaded steel pipe body during use is improved, the reinforcing rib plates can disperse and resist external forces when the threaded steel pipe body is subjected to the external forces, the second rubber plate can further elastically buffer the external pressure on the threaded steel pipe body, and the threaded steel pipe body is prevented from deforming and being damaged when subjected to external impact, extrusion or bending, thereby prolonging the service life of the threaded steel pipe and improving the use safety of the threaded steel pipe;
[0015] The rotating knob drives the bidirectional screw rod to rotate through the first rotating rod, the symmetrical movable plates are relatively moved along the bidirectional screw rod through the screw holes, the connecting rod is forced to be inclined and pushes the adjusting support rod upward, the support height of the threaded steel pipe body fixed between the first arc-shaped clamp and the second arc-shaped clamp can be quickly adjusted according to the height change of the ground, the threaded steel pipe body is quickly and horizontally laid, the installation efficiency of the threaded steel pipe body is improved, and the use flexibility and practicability of the support structure are improved. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 It is an overall structure schematic view of the utility model;
[0017] Figure 2 It is an overall structure schematic view of the T-shaped support seat of the utility model;
[0018] Figure 3 It is a structure split schematic view of the anti-deformation supporting mechanism of the utility model;
[0019] Figure 4 The structure of the reinforcing rib plate is shown in the split schematic view of the utility model.
[0020] In the figure: 1, threaded steel pipe body; 2, anti-deformation support mechanism; 3, T-shaped support seat; 4, transverse port; 5, first rotating hole; 6, vertical port; 7, side port; 8, bidirectional screw rod; 9, first rotating rod; 10, knob; 11, movable plate; 12, screw hole; 13, adjusting support rod; 14, concave block; 15, second rotating hole; 16, connecting rod; 17, second rotating rod; 18, first arc-shaped clamp; 19, second arc-shaped clamp; 20, first rubber pad; 21, fixed block; 22, first threaded short rod; 23, connecting block; 24, first mounting hole; 25, first nut; 26, second threaded short rod; 27, reinforcing rib plate; 28, second rubber plate; 29, second mounting hole; 30, second nut. DETAILED DESCRIPTION
[0021] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the utility model.
[0022] In the description of the utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "provided with", "connection" and the like should be understood broadly, for example, "connection" can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the utility model can be understood according to specific circumstances.
[0023] As Figure 1 - Figure 4As shown, a kind of anti-deformation threaded steel pipe support structure, including threaded steel pipe body 1, the outside of threaded steel pipe body 1 is equipped with several anti-deformation support mechanisms 2, and anti-deformation support mechanism 2 includes T-shaped support seat 3, bidirectional screw rod 8, movable plate 11, adjusting support rod 13, concave block 14, connecting rod 16, first arc clamp 18 and second arc clamp 19, bidirectional screw rod 8 is movably connected in the top surface of the horizontal part of T-shaped support seat 3 by the first rotating rod 9 of two ends, and adjusting support rod 13 is movably connected in the top surface of the vertical part of T-shaped support seat 3, two movable plates 11 are movably connected with bidirectional screw rod 8 by screw hole 12 on side wall respectively, and the top surface of movable plate 11 and the bottom of the two side walls of adjusting support rod 13 are fixedly connected with concave block 14 respectively, connecting rod 16 is movably connected between concave block 14 by the second rotating rod 17 of two ends, first arc clamp 18 is fixedly connected in the top end of adjusting support rod 13, and second arc clamp 19 is fixedly connected with first arc clamp 18 by first nut 25, and several reinforcing rib plates 27 are also fixedly connected between adjacent first arc clamp 18 and second arc clamp 19 by second nut 30.
[0024] As shown, Figure 2 The top surface of the horizontal part of T-shaped support seat 3 is provided with horizontal port 4, horizontal port 4 is matched with movable plate 11 to realize horizontal movement, and the left and right end walls in the inside of horizontal port 4 are respectively provided with first rotating hole 5, first rotating hole 5 is matched with first rotating rod 9 to realize rotating operation, the top surface of the vertical part of T-shaped support seat 3 is provided with vertical port 6, vertical port 6 is matched with adjusting support rod 13 to realize guiding movement, and the left and right side walls in the inside of vertical port 6 are respectively provided with side port 7, side port 7 is matched with the concave block 14 on the side wall of adjusting support rod 13 to realize vertical movement;
[0025] As shown, Figure 3As shown, the left and right ends of the bidirectional screw rod 8 are respectively fixedly installed with first rotating rods 9, and the first rotating rods 9 are movably installed in the first rotating holes 5. The outer end of the right end first rotating rod 9 is further fixedly installed with a knob 10. A screw hole 12 is formed in the side wall of the movable plate 11 and is threadedly connected with the bidirectional screw rod 8. The adjusting support rod 13 is inserted and installed in the vertical hole 6. The left and right side wall bottom ends of the adjusting support rod 13 and the top surface of the movable plate 11 are respectively fixedly installed with concave blocks 14. Second rotating holes 15 are respectively formed in the inner wall of the concave of the concave block 14. A group of symmetrical second rotating rods 17 are respectively fixedly installed at the left and right ends of the connecting rod 16, and the second rotating rods 17 are movably installed in the second rotating holes 15. Rotating the knob 10 drives the bidirectional screw rod 8 to rotate through the first rotating rod 9. After the symmetrical movable plates 11 relatively move along the bidirectional screw rod 8 through the screw holes 12 on the side wall, the connecting rod 16 is forced to tilt between the concave blocks 14 installed on the bottom surface of the movable plate 11 and the side wall of the adjusting support rod 13, and the adjusting support rod 13 is pushed upward to achieve the purpose of adjusting the support height of the threaded steel pipe body 1.
[0026] As shown in the figure, Figure 3 The first arc-shaped clamp 18 is fixedly installed at the top end of the adjusting support rod 13. The inner walls of the first arc-shaped clamp 18 and the second arc-shaped clamp 19 are respectively fixedly installed with arc-shaped first rubber pads 20. The left and right sides of the second arc-shaped clamp 19 are respectively fixedly installed with fixed blocks 21. The bottom surface of the fixed block 21 is fixedly installed with a first threaded short rod 22. The left and right sides of the first arc-shaped clamp 18 are respectively fixedly installed with connecting blocks 23. The top surface of the connecting block 23 is provided with a first installation hole 24. The first threaded short rod 22 is inserted and installed in the first installation hole 24. A first nut 25 is threadedly connected with the first threaded short rod 22. After the threaded steel pipe body 1 is placed in the interior of the first arc-shaped clamp 18, the second arc-shaped clamp 19 is installed on the top surface of the first arc-shaped clamp 18. The first threaded short rod 22 on the bottom surface of the fixed block 21 passes through the first installation hole 24 formed on the top surface of the connecting block 23, and then the first nut 25 is threadedly connected with the first threaded short rod 22. The threaded steel pipe body 1 can be fixed on the anti-deformation support mechanism 2. Through the first rubber pads 20 installed on the inner walls of the first arc-shaped clamp 18 and the second arc-shaped clamp 19, the elastic buffer damping effect can be achieved when the threaded steel pipe body 1 is supported according to the elastic material structure characteristics of the first rubber pad 20, so as to prevent the threaded steel pipe body 1 from being damaged due to vibration.
[0027] As shown in the figure, Figure 3 The outer walls of the first arc-shaped clamp 18 and the second arc-shaped clamp 19 are further fixedly installed with a plurality of groups of symmetrical second threaded short rods 26 in a ring array. The second threaded short rods 26 are used to cooperate with the installation and fixation of the reinforcing rib plates 27.
[0028] As Figure 4 The inner wall of the reinforcing rib plate 27 is fixedly installed with a second rubber plate 28, and the outer wall of the reinforcing rib plate 27 is respectively provided with a second installation hole 29 on both sides, and the second threaded short rod 26 is inserted and installed in the second installation hole 29, and the second nut 30 is screwed together with the second threaded short rod 26, the reinforcing rib plate 27 is placed between the adjacent first arc-shaped clamp 18 and the second arc-shaped clamp 19, and the second threaded short rod 26 passes through the second installation hole 29, and the second nut 30 is screwed with the second threaded short rod 26, the reinforcing rib plate 27 can be fixed between the adjacent first arc-shaped clamp 18 and the second arc-shaped clamp 19, and the second rubber plate 28 is tightly attached to the outer wall of the threaded steel pipe body 1, and the reinforcing rib layer formed by the reinforcing rib plate 27 on the outside of the threaded steel pipe body 1 can improve the strength and carrying capacity of the threaded steel pipe body 1 in use, and the second rubber plate 28 can further play the role of elastic buffer and shock absorption according to its own material properties when the threaded steel pipe body 1 is subjected to external or internal vibration, and prevent the threaded steel pipe body 1 from being deformed and damaged when subjected to external impact, extrusion or bending force.
[0029] The specific use principle of the anti-deformation support mechanism 2 in cooperation with the threaded steel pipe body 1 is as follows:
[0030] After several deformation prevention support mechanisms 2 are pre-fixed to the ground foundation of the thread steel pipe body 1 laying path, the thread steel pipe body 1 to be laid is placed inside the first arc-shaped clamp 18, and the second arc-shaped clamp 19 is installed on the top surface of the first arc-shaped clamp 18, so that the first threaded short rod 22 at the bottom surface of the fixed block 21 on both sides of the second arc-shaped clamp 19 passes through the first mounting hole 24 at the top surface of the connecting block 23 on both sides of the first arc-shaped clamp 18, and the first nut 25 is screwed together with the first threaded short rod 22, so that the thread steel pipe body 1 can be fixed on the deformation prevention support mechanism 2. In order to ensure that the thread steel pipe body 1 is laid in the same horizontal position, the height of the thread steel pipe body 1 can be adjusted. When adjusting, rotate the knob 10 on one side of the T-shaped support base 3. The knob 10 will drive the first rotating rod 9 to rotate in the first rotating hole 5. The first rotating rod 9 will drive the bidirectional screw rod 8 to rotate, so that the symmetrical movable plates 11 move relatively in the transverse port 4 along the bidirectional screw rod 8 through the screw holes 12 opened on the side wall, and in the process of moving, the second rotating hole 15 opened on the both end walls of the recess of the recessed block 14 installed on the top surface of the movable plate 11 and the both side bottom ends of the adjusting support rod 13 is forced to rotate. At this time, the connecting rod 16 will be inclined and the included angle between the T-shaped support base 3 vertical part will gradually decrease. In this way, the adjusting support rod 13 can be pushed to move upward from the vertical port 6 opened in the vertical part of the T-shaped support base 3, and the recessed block 14 at the both side bottom ends of the adjusting support rod 13 will move in the side port 7. By continuously moving the adjusting support rod 13 upward from the vertical port 6, the installation and laying height of the thread steel pipe body 1 can be adjusted until the thread steel pipe body 1 is adjusted to the appropriate height position, thereby not only improving the installation efficiency of the thread steel pipe body 1, but also improving the use flexibility and practicality of the support structure, and cooperating with the first rubber pad 20 installed in the first arc-shaped clamp 18 and the second arc-shaped clamp 19. The thread steel pipe body 1 can play a role in elastic buffering and shock absorption to prevent the thread steel pipe body from deforming due to vibration;
[0031] Finally, the reinforcing rib plates 27 are installed between the left and right adjacent first and second arc-shaped hoops 18 and 19, and when installed, the second threaded short rods 26 on the outer walls of the adjacent first and second arc-shaped hoops 18 and 19 are passed through the second installation holes 29 formed on the two sides of the outer wall of the reinforcing rib plate 27, and the second nuts 30 are screwed with the second threaded short rods 26, so that the reinforcing rib plates 27 are fixed between the adjacent first and second arc-shaped hoops 18 and 19, and the second rubber plates 28 installed on the inner wall of the reinforcing rib plate 27 are tightly attached to the outer wall of the threaded steel pipe body 1. By wrapping the reinforcing rib plates 27 around the threaded steel pipe body 1, a reinforcing rib layer is formed on the threaded steel pipe body 1, which can effectively improve the carrying capacity of the threaded steel pipe body 1. By increasing the cross-sectional area and strength of the threaded steel pipe body 1, the threaded steel pipe body 1 can withstand greater external pressure or internal fluid pressure, thereby reducing the possibility of deformation, and through the rigidity of its structure, the overall stability of the threaded steel pipe body 1 can be significantly improved. When subjected to external forces, the reinforcing rib plates 27 can disperse and resist these external forces, and in combination with the second rubber plates 28, the threaded steel pipe body 1 can further elastically buffer the external pressure, thereby slowing down or preventing the bending and deformation of the pipe, preventing the threaded steel pipe body 1 from deforming and being damaged when subjected to external impact, extrusion or bending forces, etc. At the same time, the structure of the threaded steel pipe body 1 can also be enhanced to prolong the service life of the pipe. Reducing deformation means reducing stress and fatigue damage caused by deformation, thereby prolonging the overall life of the threaded steel pipe body 1 and improving the safety of the threaded steel pipe body 1.
[0032] It is apparent for those skilled in the art that the present application is not limited to the details of the above-described exemplary embodiments, but can be implemented in other concrete forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all aspects as illustrative and not restrictive, and the scope of the present application is defined by the appended claims rather than the above description, and it is intended to encompass all changes falling within the meaning and range of equivalents of the elements of the claims. Any reference signs in the claims should not be considered as limiting the claims to which they relate.
Claims
1. A deformation-proof threaded steel pipe support structure comprising a threaded steel pipe body (1), characterized in that: The threaded steel pipe body (1) is externally provided with a plurality of deformation prevention support mechanisms (2), and the deformation prevention support mechanism (2) comprises a T-shaped support base (3), a bidirectional screw rod (8), a movable plate (11), an adjusting support rod (13), a concave block (14), a connecting rod (16), a first arc-shaped clamp (18) and a second arc-shaped clamp (19), the bidirectional screw rod (8) is movably connected to the top surface of the transverse part of the T-shaped support base (3) through the first rotating rods (9) at both ends, and the adjusting support rod (13) is movably connected to the top surface of the vertical part of the T-shaped support base (3), the two movable plates (11) are movably connected with the bidirectional screw rod (8) through the screw holes (12) in the side walls, respectively, and the top surface of the movable plate (11) and the bottom of the two side walls of the adjusting support rod (13) are fixedly connected with the concave blocks (14), respectively, the connecting rod (16) is movably connected between the concave blocks (14) through the second rotating rods (17) at both ends, the first arc-shaped clamp (18) is fixedly connected to the top end of the adjusting support rod (13), and the second arc-shaped clamp (19) is fixedly connected with the first arc-shaped clamp (18) through the first nut (25), and a plurality of reinforcing rib plates (27) are fixedly connected between the adjacent first arc-shaped clamps (18) and second arc-shaped clamps (19) through the second nuts (30).
2. A threaded steel pipe support structure according to claim 1, wherein: The top surface of the transverse part of the T-shaped support base (3) is provided with a transverse opening (4), and the left and right end walls inside the transverse opening (4) are respectively provided with first rotating holes (5), the top surface of the vertical part of the T-shaped support base (3) is provided with a vertical opening (6), and the left and right side walls inside the vertical opening (6) are respectively provided with side openings (7).
3. A threaded steel pipe support structure according to claim 2, wherein: The left and right ends of the bidirectional screw rod (8) are fixedly provided with first rotating rods (9), respectively, and the first rotating rods (9) are movably installed in the first rotating holes (5), the outer side of the right end of the first rotating rod (9) is further fixedly provided with a knob (10), the side wall of the movable plate (11) is provided with a screw hole (12) and is threadedly connected with the bidirectional screw rod (8) through the screw hole (12), the adjusting support rod (13) is insertedly installed in the vertical opening (6), and the left and right side walls of the bottom end of the adjusting support rod (13) and the top surface of the movable plate (11) are fixedly provided with concave blocks (14), respectively, the left and right side walls of the concave blocks (14) are respectively provided with second rotating holes (15) at both ends of the recess inner wall, the left and right ends of the connecting rod (16) are fixedly provided with a group of symmetrical second rotating rods (17), respectively, and the second rotating rods (17) are movably installed in the second rotating holes (15).
4. A threaded steel pipe support structure according to claim 3, wherein: The first arc-shaped clamp (18) is fixedly installed at the top end of the adjusting support rod (13), and the inner walls of the first arc-shaped clamp (18) and the second arc-shaped clamp (19) are respectively fixedly installed with arc-shaped first rubber pads (20).
5. A threaded steel pipe support structure according to claim 4, wherein: The outer walls of the first arc-shaped clamp (18) and the second arc-shaped clamp (19) are also fixedly installed with a plurality of groups of symmetrical second threaded short rods (26) in a ring array.
6. A threaded steel pipe support structure according to claim 5, wherein: The inner wall of the reinforcing rib plate (27) is fixedly installed with a second rubber plate (28), and the outer walls of the reinforcing rib plate (27) are respectively provided with second mounting holes (29), the second threaded short rods (26) are insertedly installed in the second mounting holes (29), and the second nuts (30) are threadedly connected with the second threaded short rods (26).