CN219369519U - Concrete reinforcing bar rust cleaning test device - Google Patents

Abstract

The utility model discloses a concrete reinforcement rust removal test device, which comprises a sacrificial anode unit, an impressed current unit and a bearing bottom plate, wherein the sacrificial anode unit is arranged on the bearing bottom plate; the bearing bottom plate is used for placing a plurality of concrete plates which are penetrated with reinforced bars with different corrosion degrees and driving the concrete plates to be immersed into the electrolytic cell, and upright posts or bent posts are respectively detachably arranged at four corners of the top surface of the bearing bottom plate; the sacrificial anode unit comprises an active anode plate and a conducting wire; the impressed current unit comprises an inert anode network and a direct current power supply module. In the utility model, the sacrificial anode unit and the impressed current unit are quickly and conveniently assembled and disassembled on the bearing bottom plate, the test equipment is convenient to replace, the test mode is quickly switched, the test working efficiency is improved, the work load of an experimenter is lightened, one set of device can realize two test methods, and the whole set of test device has simple structure and easy operation, thereby not only reducing occupied laboratory space, but also reducing the cost and the cost of the test.

Description

Concrete reinforcing bar rust cleaning test device

Technical Field

The utility model relates to the technical field of electrolytic rust removal of reinforcing steel bars, in particular to a concrete reinforcing steel bar rust removal test device.

Background

The durability of reinforced concrete is a complex system engineering, and is affected by many factors, since the structural member must be able to withstand environmental effects and time, environmental factors become the focus of influencing the durability of the structural member, and corrosion factors, particularly corrosion damage of the steel bars, are important points of concern in the engineering community.

At present, the method for removing rust from the steel bars is mainly divided into the following steps: manual rust removal, chemical rust removal (also known as acid washing rust removal), mechanical rust removal, and electrolytic rust removal. Each rust removing method has unique working characteristics and applicable conditions, and thus, the rust removing methods coexist with each other. The electrolytic rust removal method has the advantages of less loss to the steel bar, no limitation to the appearance of the steel bar, capability of operating together with the concrete slab, and the like, and is widely applied to various electrolytic simulation test researches on the steel bar in a laboratory. In the prior art, a common reinforcement bar electrolytic rust removal method in a laboratory is provided with an impressed current method and a sacrificial anode method, each electrolytic method is generally corresponding to test equipment, a large amount of equipment not only occupies more space in the laboratory, but also increases the cost and the cost of the test, and in the actual test process, if the problem that the test operation needs to be carried out on the same test sample by switching different test equipment is encountered, the defects of troublesome equipment replacement and inconvenient mode switching exist.

Disclosure of Invention

The utility model aims to solve the technical problem of providing the concrete reinforcement rust removal test device which is simple and practical in structure, convenient and efficient to operate.

In order to solve the technical problems, the utility model adopts the following technical scheme: a concrete reinforcement rust removal test device comprises a sacrificial anode unit, an impressed current unit and a bearing bottom plate;

the bearing bottom plate is used for placing a plurality of concrete plates which are penetrated with reinforced bars with different corrosion degrees and driving the concrete plates to be immersed into the electrolytic cell, and upright posts or bent posts are respectively detachably arranged at four corners of the top surface of the bearing bottom plate;

the sacrificial anode unit comprises an active anode plate and a wire, wherein the active anode plate can pass through the upright post from top to bottom and is horizontally pressed on the concrete slab, one end of the wire is connected with the active anode plate, and the other end of the wire is connected with the steel bar;

the external current unit comprises an inert anode net and a direct current power supply module, the inert anode net can synchronously penetrate through the bent column and the steel bar from the side face and vertically props against the steel bar, the anode of the direct current power supply module is connected with the inert anode net, and the cathode of the direct current power supply module is connected with the steel bar.

Further, the impressed current unit also comprises an inert anode belt, the inert anode belt can be wound between two bent columns positioned on one side of the concrete slab and a plurality of reinforcing steel bars, the anode of the direct current power supply module is connected with the inert anode belt, and the cathode of the direct current power supply module is connected with the reinforcing steel bars.

Further, the impressed current unit also comprises at least two conductive wire clamps, wherein the conductive wire clamps are respectively and electrically connected with the cathode end and the anode end of the direct current power supply module and are used for clamping the reinforcing steel bars and the inert anode net/inert anode belt.

Further, a locking bolt member is detachably mounted on the bent column in a threaded manner, and the inert anode mesh vertically inserted in the bent column is locked and fixed through the locking bolt member.

Further, the sacrificial anode unit further comprises a conductive soft layer, the four corners of the active anode plate are respectively provided with mounting holes matched with the upright posts in a penetrating mode, the conductive soft layer is made of flexible conductive materials, is arranged on the bottom surface of the active anode plate in the middle and does not exceed the position of the mounting holes, locking bolt pieces are detachably arranged on the upright posts in a threaded mode, the active anode plate horizontally penetrating through the upright posts is locked and fixed through the locking bolt pieces, and the conductive soft layer is clamped between the active anode plate and the concrete slab.

Further, the sacrificial anode unit further comprises a welding seat and an insulating sealing sleeve, wherein the welding seat is fixed on the active anode plate, one end of the wire is fixed to the welding seat, the other end of the wire is fixed to the insulating sealing sleeve, and the insulating sealing sleeve is detachably sleeved on the steel bar.

Further, a groove for placing the concrete slab is formed in the middle of the top surface of the bearing bottom plate, a plurality of through holes are formed in the bottom surface of the groove at intervals, and a plurality of positioning columns are fixed on the side edge of the top surface of the bearing bottom plate at intervals;

the bottom surface of the bearing bottom plate is fixedly attached with an elastic sealing net used for coating the through holes, and the elastic sealing net can be folded and coated on the top surface of the bearing bottom plate and is shaped with the positioning column hooks.

Further, still include support module and pulley lifting rope module, the support module is fixed one side on the electrolytic cell is used for suspending and supporting the loading floor, pulley lifting rope module installs on the support module, have with the loading floor is put down submergence or is pulled up and is put forward the motion stroke of electrolytic cell.

Further, rope penetrating holes are respectively formed in two side ends of the bearing bottom plate, and ropes used for being connected to the pulley lifting rope modules penetrate through the rope penetrating holes.

Further, four corners of the top surface of the bearing bottom plate are respectively provided with assembly threaded holes which can be matched with the upright posts or the bent posts in a threaded manner.

The beneficial effects of the utility model are as follows:

according to the utility model, the bearing bottom plates which are matched with the sacrificial anode unit and the external current unit are adopted to place the concrete plates which are penetrated with the reinforcing steel bars with different corrosion degrees, and the concrete plates can be driven to be immersed into the electrolytic cell together to generate different reactions, on one hand, the sacrificial anode unit and the external current unit are quickly and conveniently assembled and disassembled on the bearing bottom plates, the test equipment is quickly and conveniently replaced, the test mode is quickly switched, the test progress is not influenced, the test working efficiency is improved, the work load of an experimenter is reduced, on the other hand, one set of device can realize two test methods, and the whole set of test device has a simple structure and easy operation, not only can reduce occupied laboratory space, but also can reduce the cost and the cost of the test.

Drawings

FIG. 1 is a schematic illustration of the experimental operation of an embodiment of the present utility model.

Fig. 2 is a block diagram of a load floor of an embodiment of the utility model with the elastic dense web removed.

Fig. 3 is an assembly view of a load floor and posts according to an embodiment of the utility model.

Fig. 4 is an assembly view of a load floor and a corner post according to an embodiment of the present utility model.

FIG. 5 is an assembled side view of a sacrificial anode unit and a carrier base plate according to an embodiment of the utility model.

FIG. 6 is a side view of an embodiment of the utility model assembled with a load floor using an inert anode screen for an external current cell.

FIG. 7 is an elevation view of an embodiment of the utility model assembled with a load floor using inert anode strips.

Fig. 8 is an overall construction view of a concrete slab in which a plurality of reinforcing bars having different degrees of rust are interposed in accordance with an embodiment of the present utility model.

The components in the drawings are marked as follows: 1. a load-bearing bottom plate; 2. a groove; 3. a through hole; 4. assembling the threaded hole; 5. threading the rope hole; 6. positioning columns; 7. an elastic dense net; 8. a sacrificial anode unit; 9. an external current unit; 10. a column; 11. a curved column; 12. a locking bolt member; 13. a reactive anode plate; 14. a conductive soft layer; 15. a wire; 16. a welding seat; 17. an insulating sealing sleeve; 18. an inert anode mesh; 19. an inert anode belt; 20. a direct current power supply module; 2001. a conductive wire clip; 21. a concrete slab; 22. reinforcing steel bars; 23. an electrolytic cell; 24. a bracket module; 25. and a pulley lifting rope module.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. Embodiments and features of embodiments in this application may be combined with each other without conflict. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

See fig. 1-8.

The utility model provides a concrete reinforcement rust removal test device, which comprises a sacrificial anode unit 8, an impressed current unit 9 and a bearing bottom plate 1, wherein the sacrificial anode unit is arranged on the bearing bottom plate;

the bearing bottom plate 1 is used for placing a concrete slab 21 penetrated with a plurality of reinforcing steel bars 22 with different corrosion degrees, driving the concrete slab 21 to be immersed into an electrolytic cell 23, and the four corners of the top surface of the bearing bottom plate 1 are respectively and detachably provided with an upright post 10 or a bent post 11;

the sacrificial anode unit 8 comprises an active anode plate 13 and a lead 15, wherein the active anode plate 13 can pass through the upright post 10 from top to bottom and is horizontally pressed on the concrete slab 21, one end of the lead 15 is connected with the active anode plate 13, and the other end is connected with the steel bar 22;

the impressed current unit 9 comprises an inert anode net 18 and a direct current power supply module 20, wherein the inert anode net 18 can synchronously pass through the bent columns 11 and the steel bars 22 from the side surface and vertically props against the steel bars 22, the anode of the direct current power supply module 20 is connected with the inert anode net 18, and the cathode is connected with the steel bars 22.

According to the utility model, the bearing bottom plates which are matched with the sacrificial anode unit and the external current unit are adopted to place the concrete plates which are penetrated with the reinforcing steel bars with different corrosion degrees, and the concrete plates can be driven to be immersed into the electrolytic cell together to generate different reactions, on one hand, the sacrificial anode unit and the external current unit are quickly and conveniently assembled and disassembled on the bearing bottom plates, the test equipment is quickly and conveniently replaced, the test mode is quickly switched, the test progress is not influenced, the test working efficiency is improved, the work load of an experimenter is reduced, on the other hand, one set of device can realize two test methods, and the whole set of test device has a simple structure and easy operation, not only can reduce occupied laboratory space, but also can reduce the cost and the cost of the test.

In an embodiment, the impressed current unit 9 further includes an inert anode belt 19, the inert anode belt 19 may be wound between two bent columns 11 and a plurality of reinforcing bars 22 located at one side of the concrete slab 21, the anode of the dc power module 20 is connected to the inert anode belt 19, and the cathode is connected to the reinforcing bars 22. So designed, the impressed current unit 9 has two implementation modes, one is that the inert anode net 18 is utilized, the steel bar 22 passes through the meshes of the inert anode net 18 so as to enable the inert anode net 18 and the steel bar to be in direct contact and fixed, and the other is that the inert anode belt 19 is utilized, the inert anode belt 19 is wound on the steel bar 22 so as to enable the inert anode net 18 and the inert anode belt 19 to be in direct contact and fixed, wherein titanium can be used as the inert anode net 18 and the inert anode belt 19;

it should be noted that the impressed current CP is considered as an active method, and the rectifier and the inert anode are adopted to protect the metal structure as the cathode, namely, the following steps are implemented in the device: a low direct current flows from the inert anode net 18 or the inert anode belt 19 to the surface of the steel 22 through the concrete slab 21, and the external current unit 9 has the advantage that the real-time adjustment of the current flowing to the steel 22 can be realized by directly adjusting the output of the direct current power supply module 20, so that the remote automatic monitoring can be realized, and the device is economical for facilities with larger required current and longer protection time and is suitable for high resistivity or severe conditions.

In one embodiment, the impressed current unit 9 further includes at least two conductive clamps 2001, where the conductive clamps 2001 are electrically connected to the cathode terminal and the anode terminal of the dc power module 20, respectively, and are used for clamping the steel bar 22 and the inert anode mesh 18/inert anode belt 19. In this way, the periphery of the conductive wire clamp 2001 should be wrapped with a sealed insulating cable sleeve, the conductive chuck should be made of anti-corrosion and anti-rust conductive materials, before the impressed current test is performed, the conductive wire clamp 2001 should be clamped on the steel bar 22 and the inert anode net 18 or the inert anode belt 19 in advance, when the test is performed, the conductive wire clamp 2001 will be immersed in the electrolytic cell 23 together with the sinking of the bearing bottom plate 1 and the concrete slab 21, and the direct current power supply module 20 is fixed outside the electrolytic cell 23 without sinking into the electrolytic cell 23.

In one embodiment, the bent pillar 11 is detachably screwed with a locking bolt member 12, and the inert anode net 18 vertically inserted in the bent pillar 11 is locked and fixed by the locking bolt member 12. By means of the design, when the external current unit 9 adopts the inert anode net 18, the inert anode net 18 is vertically inserted into the bent column 11, at the moment, the inert anode net 18 also penetrates through the steel bars 22 in a horizontal state, so that the inert anode net 18 is abutted against the steel bars 22, the inert anode net 18 is abutted and fixed on the bent column 11 by the locking bolt piece 12, phenomena of drifting, loosening and the like when immersed in the electrolytic cell 23 are prevented, and the influence on a test is avoided.

In an embodiment, the sacrificial anode unit 8 further includes a conductive soft layer 14, four corners of the active anode plate 13 are respectively provided with mounting holes that are matched with the stand column 10 in a penetrating manner, the conductive soft layer 14 is made of a flexible conductive material, is centrally disposed on the bottom surface of the active anode plate 13 and does not exceed the position of the mounting holes, a locking bolt member 12 is detachably screwed on the stand column 10, the active anode plate 13 that is horizontally penetrated on the stand column 10 is locked and fixed by the locking bolt member 12, and the conductive soft layer 14 is sandwiched between the active anode plate 13 and the concrete slab 21. In this way, the active anode plate 13 may be a metal plate with extremely strong activity, such as magnesium, aluminum, zinc, etc., and the conductive soft layer 14 is fixed on the bottom surface of the active anode plate 13 for directly contacting the concrete slab 21, and because the surface of the concrete slab 21 may be uneven and irregular, the conductive soft layer 14 has flexibility and strong shaping capability, so that the active anode plate 13 is stably fixed on the concrete slab 21, and the conductive soft layer 14 itself has hydrophilicity and can keep ionic conductivity, thus playing an important role in ensuring that the active anode plate 13 is in a correct position after the installation is completed even in the electrolytic cell 23 or low-humidity environment;

it should be noted that the sacrificial anode CP used in the sacrificial anode unit 8 is considered as a passive method, and the sacrificial anode CP is based on the principle of two corrosion potentials different from each other, and connects a metal with a more negative potential to the protected metal, where the metal and the protected metal form a battery in an electrolyte, and the anode corrodes due to the negative potential, and the protected metal is protected due to cathodic polarization, i.e. the present device is represented as: the active anode plate 13 and the steel bar 22 are connected by the lead 15, the active anode plate 13 is more active and is represented as an anode, the steel bar 22 is weaker in activity and is represented as a cathode, the anode oxidation is protected by corrosion cathode reduction, rust removal is achieved, the sacrificial anode unit 8 has the advantages that an external power supply is not required to be additionally arranged, the sacrificial anode unit can be dissolved and consumed by the sacrificial anode unit, the sacrificial anode unit is suitable for places and small-scale movable objects with no power supply or inconvenient wire pulling, the application is more convenient and economical, the cost is lower, the disposable investment cost is less, the maintenance probability is small, the overstock phenomenon is not worry, and the utilization rate of current protection can be improved.

In an embodiment, the sacrificial anode unit 8 further includes a welding base 16 and an insulating sealing sleeve 17, the welding base 16 is fixed on the active anode plate 13, one end of the wire 15 is fixed to the welding base 16, the other end is fixed to the insulating sealing sleeve 17, and the insulating sealing sleeve 17 is detachably sleeved on the reinforcing steel bar 22. In this way, the wire 15 may be made of a conductive material such as copper wire, and the use of the welding seat 16 or the insulating sealing sleeve 17 does not affect the conductivity of the wire 15 between the active anode plate 13 and the reinforcing steel bar 22.

In an embodiment, a groove 2 for placing the concrete slab 21 is centrally formed in the top surface of the bearing bottom plate 1, a plurality of through holes 3 are formed in the bottom surface of the groove 2 at intervals, and a plurality of positioning columns 6 are fixed on the side edge of the top surface of the bearing bottom plate 1 at intervals;

the elastic dense net 7 for coating the through holes 3 is fixedly attached to the bottom surface of the bearing bottom plate 1, and the elastic dense net 7 can be folded and coated to the top surface of the bearing bottom plate 1 and is hooked with the positioning column 6 for shaping. In this way, the concrete slab 21 should be placed in the groove 2 of the bearing bottom plate 1, and the elastic dense net 7 is used to wrap and tighten the concrete slab 21 in the bearing bottom plate 1, which can prevent the concrete slab 21 from loosening and drifting after sinking and immersing in the electrolytic cell 23, and prevent the soil residue on the concrete slab 21 from immersing in water and falling off to the burden of cleaning work in the electrolytic cell 23, wherein the mesh of the elastic dense net 7 can be fixed or disassembled by matching the hanging of the mesh and the positioning column 6, and the through holes 3 can increase the contact fusion speed of the concrete slab 21 and the water in the electrolytic cell 23.

In one embodiment, the electrolytic cell further comprises a bracket module 24 and a pulley lifting rope module 25, wherein the bracket module 24 is fixed on one side of the electrolytic cell 23 and is used for suspending and supporting the bearing bottom plate 1, and the pulley lifting rope module 25 is installed on the bracket module 24 and has a movement stroke for immersing or pulling up the bearing bottom plate 1 to lift the electrolytic cell 23. The design like this, load-bearing bottom plate 1 with pulley lifting rope module 25 is connected, and both can dismantle the hoist and mount on the support module 24, can adopt manual drive or electric drive's mode, will the hoist and mount under the pulley lifting rope module 25 load-bearing bottom plate 1 is put down and is submerged into in the electrolytic bath 23 or promote and carry out electrolytic bath 23, the simple structure of adoption, the cost is controllable, easy to operate, need note that whichever kind of method is adopted carries out the test, all need take place in electrolytic bath 23, the injection in electrolytic bath 23 is ordinary running water or pure water can.

In an embodiment, two side ends of the load-bearing bottom plate 1 are respectively provided with a rope threading hole 5, and ropes used for being connected to the pulley hanging rope module 25 are threaded in the rope threading holes 5. By means of the design, the bearing bottom plate 1 can be hung below the pulley hanging rope module 25 through the rope and the threading and fixing of the threading holes 5.

In an embodiment, four corners of the top surface of the load-bearing bottom plate 1 are respectively provided with an assembling threaded hole 4 which can be matched with the upright post 10 or the bent post 11 in a threaded manner. In this way, the stand column 10 is suitable for the sacrificial anode unit 8, the bent column 11 is suitable for the external current unit 9, and the stand column 10 or the bent column 11 can be replaced on the bearing bottom plate 1, so that different test modes can be suitable.

It should be understood that the examples and embodiments described herein are for illustrative purposes only and are not intended to limit the present utility model, and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application.

Claims (10)

1. A concrete reinforcing bar rust cleaning test device, its characterized in that: comprises a sacrificial anode unit (8), an impressed current unit (9) and a bearing bottom plate (1);

the bearing bottom plate (1) is used for placing a concrete slab (21) which is penetrated with a plurality of steel bars (22) with different corrosion degrees, driving the concrete slab (21) to be immersed into the electrolytic cell (23), and the upright posts (10) or the bent posts (11) are respectively detachably arranged at four corners of the top surface of the bearing bottom plate (1);

the sacrificial anode unit (8) comprises an active anode plate (13) and a wire (15), wherein the active anode plate (13) can pass through the upright post (10) from top to bottom and is horizontally pressed on the concrete slab (21), one end of the wire (15) is connected with the active anode plate (13), and the other end of the wire is connected with the steel bar (22);

the external current unit (9) comprises an inert anode net (18) and a direct current power supply module (20), the inert anode net (18) can synchronously penetrate through the bent column (11) and the reinforcing steel bar (22) from the side face and vertically props against the reinforcing steel bar (22), and the anode of the direct current power supply module (20) is connected with the inert anode net (18) and the cathode of the direct current power supply module is connected with the reinforcing steel bar (22).

2. The concrete reinforcing steel bar rust removal test apparatus as set forth in claim 1, wherein: the impressed current unit (9) also comprises an inert anode belt (19), the inert anode belt (19) can be wound between two bent columns (11) positioned on one side of the concrete slab (21) and a plurality of reinforcing steel bars (22), the anode of the direct current power supply module (20) is connected with the inert anode belt (19), and the cathode is connected with the reinforcing steel bars (22).

3. The concrete reinforcing steel bar rust removal test apparatus as set forth in claim 2, wherein: the externally applied current unit (9) further comprises at least two conductive wire clamps (2001), wherein the conductive wire clamps (2001) are respectively and electrically connected to the cathode end and the anode end of the direct current power supply module (20) and are used for clamping the reinforcing steel bars (22) and the inert anode net (18)/the inert anode belt (19).

4. The concrete reinforcing steel bar rust removal test apparatus as set forth in claim 1, wherein: the bending column (11) is detachably provided with a locking bolt piece (12), and the inert anode net (18) vertically inserted in the bending column (11) is locked and fixed through the locking bolt piece (12).

5. The concrete reinforcing steel bar rust removal test apparatus as set forth in claim 1, wherein: the sacrificial anode unit (8) further comprises a conductive soft body layer (14), the four corners of the active anode plate (13) are respectively provided with mounting holes which are penetrated and matched with the stand columns (10), the conductive soft body layer (14) is made of flexible conductive materials, the conductive soft body layer is arranged at the bottom surface of the active anode plate (13) in the middle and does not exceed the position of the mounting holes, the stand columns (10) are detachably provided with locking bolt pieces (12) in a threaded mode, the active anode plate (13) which is penetrated and inserted on the stand columns (10) horizontally is locked and fixed through the locking bolt pieces (12), and the conductive soft body layer (14) is clamped between the active anode plate (13) and the concrete slab (21).

6. The concrete reinforcing steel bar rust removal test apparatus as set forth in claim 1, wherein: the sacrificial anode unit (8) further comprises a welding seat (16) and an insulating sealing sleeve (17), the welding seat (16) is fixed on the active anode plate (13), one end of the wire (15) is fixed to the welding seat (16), the other end of the wire is fixed to the insulating sealing sleeve (17), and the insulating sealing sleeve (17) is detachably sleeved on the reinforcing steel bar (22).

7. The concrete reinforcing steel bar rust removal test apparatus as set forth in claim 1, wherein: the top surface of the bearing bottom plate (1) is provided with a groove (2) for placing the concrete slab (21) in the middle, a plurality of through holes (3) are formed in the bottom surface of the groove (2) at intervals, and a plurality of positioning columns (6) are fixed on the side edge of the top surface of the bearing bottom plate (1) at intervals;

the bottom surface of the bearing bottom plate (1) is fixedly attached with an elastic sealing net (7) used for coating the through holes (3), and the elastic sealing net (7) can be folded and coated on the top surface of the bearing bottom plate (1) and is hooked with the positioning column (6) for shaping.

8. The concrete reinforcing steel bar rust removal test apparatus as set forth in claim 1, wherein: still include support module (24) and pulley lifting rope module (25), support module (24) are fixed one side on electrolytic cell (23) for hang and support load-bearing bottom plate (1), pulley lifting rope module (25) are installed on support module (24), have with load-bearing bottom plate (1) is put down submergence or is pulled up and is put forward the motion stroke of electrolytic cell (23).

9. The concrete reinforcing steel bar rust removal test apparatus as set forth in claim 8, wherein: the two side ends of the bearing bottom plate (1) are respectively provided with a rope threading hole (5), and ropes used for being connected to the pulley lifting rope modules (25) are threaded in the rope threading holes (5).

10. The concrete reinforcing steel bar rust removal test apparatus as set forth in claim 1, wherein: four corners of the top surface of the bearing bottom plate (1) are respectively provided with assembly threaded holes (4) which can be matched with the upright posts (10) or the bent posts (11) in a threaded manner.