CN113774901B - Construction method for rotary-digging hole-forming cast-in-place screw pile - Google Patents

Abstract

The application relates to a construction method of a rotary excavating hole-forming cast-in-place threaded pile, which relates to the field of cast-in-place pile construction and comprises the following steps: s1, paying off the pile position; s2, positioning the pile core; s3, positioning a drill bit; s4, embedding a pile casing; s5, drilling; s6, installing a reinforcement cage; and S7, pouring concrete. This application has the location effect of being convenient for realize drill bit and stake hole center, promotes the precision and the work efficiency of drilling, has the restriction effect to the come-up of steel reinforcement cage simultaneously, ensures going on smoothly of filling screw pile construction.

Description

Construction method for rotary drilling hole-forming cast-in-place threaded pile

Technical Field

The application relates to the field of cast-in-place pile construction, in particular to a rotary drilling hole-forming cast-in-place screw pile construction method.

Background

The existing cast-in-place reinforced concrete pile is formed by directly forming a hole on a site pile position, then pouring concrete in the hole or placing a reinforcement cage and pouring concrete, compared with a hammering method of sinking into the pile, the construction noise and the vibration are much smaller, and the pile with the diameter larger than that of a prefabricated pile can be usually built and can be used on various foundations. The steel reinforcement cage just uses the reinforcing bar of corresponding diameter, the cage steel reinforcement frame who forms together links together according to certain appearance requirement, commonly in the foundation engineering etc. of modern building, use the steel reinforcement cage as the skeleton promptly, use the concrete of certain intensity grade to pour according to the specified technology, maintenance through certain time, alright reach its design bearing capacity, so that guarantee the construction requirement and the operation requirement in future of its upper project, the steel reinforcement cage mainly plays tensile effect, the compressive strength of concrete is high but tensile strength is very low, the steel reinforcement cage can play the effect of restraint to pile body concrete, improve the vertical bearing capacity of pile foundation.

The prior Chinese patent with the patent application number of CN202110404013.5 provides a rotary excavating hole-forming cast-in-place screw pile construction method in permafrost regions, belongs to the technical field of cast-in-place pile engineering construction, and is used for solving the technical problems of high construction difficulty and low efficiency of foundation piles in the permafrost regions. The construction steps comprise: preparing for construction; pile position lofting; drilling by a rotary drilling rig; rotating and extruding threads by using a special spinning thread extruding and expanding drill bit; reversely lifting the drill and pouring concrete until a designed thread-free area is filled, and stopping pouring; installing a reinforcement cage; installing a steel casing; concrete pouring is continued; and after the cast-in-place pile is formed, pile foundation detection is carried out. According to the construction method, after the hole is formed at the pile position in a rotary drilling mode, a special spinning extruding and expanding thread drill is adopted to rotatably drill threads on the inner wall of the pile hole, a reinforcement cage and a steel casing are arranged in the cast-in-place thread pile, the pile body structure has high strength and good stability, and the thread pile has good vertical bearing and anti-freezing pulling performance after being formed.

Aiming at the related technologies, the inventor thinks that in the pile position lofting process, the position of the rotary drilling bit is adjusted to be aligned to the center position of the cross line of the pile hole after being observed by a worker, and the pile hole is easily positioned inaccurately when the visual angles are different, so that the defect of pile hole positioning exists.

Disclosure of Invention

In order to solve the problem that pile hole positioning is not accurate, the application provides a rotary drilling hole-forming pouring threaded pile construction method.

The construction method for the rotary drilling hole-forming cast-in-place threaded pile adopts the following technical scheme:

a construction method for rotary drilling hole-forming cast-in-place threaded piles comprises the following steps:

s1, paying off pile positions, determining the distribution and the positions of rotary-digging hole-forming cast-in-place threaded piles, determining each parameter of each pile, lofting all the pile positions, and marking the positions of pile cores by using cross lines;

s2, positioning the pile core, excavating a positioning hole in the pile core, placing the positioning rod in the positioning hole, penetrating the positioning rod through the center of the positioning frame, and finishing the placement of the positioning frame through the matching action of the identification device and the positioning rod;

s3, positioning the drill bit, installing a driving piece at the center position of the drill bit, positioning the rotary drilling position of the drill bit by using the driving piece and the identification device, and detaching the driving piece;

s4, embedding a pile casing at the position to be drilled;

s5, drilling, namely, drilling by using a drilling machine, pulling out the rotary drilling bit after the drilling depth reaches the designed pile elevation, cleaning the hole, and detecting various indexes of the pile hole;

s6, installing a reinforcement cage, and hoisting the reinforcement cage into the pile hole;

s7, pouring concrete, and pouring the concrete into the pile hole after secondary hole cleaning; and completing the pouring work after the pile is formed.

Through adopting above-mentioned technical scheme, confirm the center in stake hole site and every stake hole, set up the locating hole with the position of stake heart, and peg graft the locating lever in the locating hole, position relation through locating lever and identification means, confirm identification means and locating hole coaxial line's position, rethread driving piece is to identification means's drive relation, accomplish the location effect of drill bit, dismantle behind driving piece and the identification means, bury the casing underground, drill to stake hole site, clear hole back installation steel reinforcement cage, treat that steel reinforcement cage accomplishes the installation back, at steel reinforcement cage top installation construction platform, avoid the steel reinforcement cage come-up, after the concrete has been poured, demolish construction platform, accomplish the work of pouring screw pile.

Optionally, the identification device includes two transmission blocks and two identification rods, the locating rack is symmetrically provided with two through holes along a vertical symmetry plane thereof, the transmission blocks are slidably connected in the through holes, one end of the transmission blocks is abutted to the identification rods, the other end of the transmission blocks is abutted to the outer wall of the locating rod, the identification rods are vertically arranged and hinged to the locating rack, and a reset piece is arranged between the locating rack and the identification rods.

Through adopting above-mentioned technical scheme, through placing the driving piece in the position between two transmission piece tip, the transmission piece slides in the through-hole to drive the marker post, make the marker post take place to swing, through observing two marker post swing circumstances and swing angle, realize the position control effect to the drill bit.

Optionally, the marker rod with rotate between the locating rack and be connected with the articulated shaft, the axis direction of articulated shaft is the level setting, the piece that resets sets up to the torsional spring, the both ends of torsional spring respectively with the marker rod and fixed connection between the locating rack.

Through adopting above-mentioned technical scheme, when the marker post took place to swing, the torsional spring took place to warp, after removing the effort of applying to the marker post, under the spring action that the torsional spring resumes former shape, the marker post swung to initial position, realized the automatic re-setting effect of marker post.

Optionally, the driving member is provided as a driving rod, the diameter of the section circle of the driving rod is unchanged after gradually increasing towards the drill bit, and the outer wall of the driving rod abuts against the end of the driving block.

Through adopting above-mentioned technical scheme, when moving towards the locating hole along with the actuating lever, the cross-section circle diameter crescent of actuating lever and driving block butt position, consequently the driving block is driven towards the motion of sign pole direction.

Optionally, the through-hole inner wall is provided with two spacing grooves, two stoppers of driving block outer wall fixedly connected with, stopper sliding connection in the spacing inslot, the both ends of spacing groove are closed setting.

Through adopting above-mentioned technical scheme, the stopper moves at the spacing inslot, under the limiting block and the limiting groove's mating reaction, realizes the restriction effect to the drive block direction of motion.

Optionally, the limiting groove is far away from the inner wall of the end part of the driving rod and is fixedly connected with a spring, and the other end of the spring is fixedly connected with the limiting block.

Through adopting above-mentioned technical scheme, when the transmission piece promoted the sign pole and takes place the swing, the spring was compressed this moment, and under the elastic force effect of spring, the transmission piece resumes to the position of just knowing.

Optionally, one end of the driving rod, which is far away from the positioning frame, is fixedly connected with a magnet block used for the drill bit to adsorb.

Through adopting above-mentioned technical scheme, the magnet piece is used for realizing the releasable connection between actuating lever and the drill bit.

Optionally, in S6, after the steel reinforcement cage is installed, a construction platform disposed on the ground is fixedly installed at the top end of the steel reinforcement cage, and the construction platform is used for placing a balancing weight or a concrete pouring device.

Through adopting above-mentioned technical scheme, carry out heavy burden on the construction platform for add weight to the steel reinforcement cage, avoid pouring the concrete in-process, the come-up of steel reinforcement cage.

Optionally, the reinforcing bar top fixedly connected with threaded rod of steel reinforcement cage, construction platform bottom surface fixedly connected with a plurality of with the dead lever that the threaded rod corresponds, the dead lever overcoat is equipped with the thread bush, the thread bush with threaded rod threaded connection, the thread bush with be provided with the joint subassembly between the dead lever.

Through adopting above-mentioned technical scheme, the screw thread bush and threaded rod threaded connection realize the installation effect between construction platform and the steel reinforcement cage under the effect of joint subassembly and the screw-thread fit of screw thread bush and threaded rod.

Optionally, the joint subassembly includes joint ring and butt dish, the joint ring with the thread bush keep away from in the one end fixed connection of threaded rod, the butt dish with the dead lever is close to in the one end fixed connection of threaded rod, the joint ring with the butt dish butt.

Through adopting above-mentioned technical scheme, under the effect of dragging of the threaded connection of thread bush and threaded rod and joint ring and butt joint dish, accomplish steel reinforcement cage and construction platform's installation work.

In summary, the present application includes at least one of the following beneficial technical effects:

1. determining the position of each pile hole and the center of each pile hole, arranging a positioning hole at the position of each pile core, inserting a positioning rod into the positioning hole, determining the coaxial position of the identification device and the positioning hole according to the position relation of the positioning rod and the identification device, and finishing the positioning effect of the drill bit according to the driving relation of the driving piece to the identification device;

2. when the driving rod moves towards the positioning hole, the diameter of the cross section circle of the abutting position of the driving rod and the transmission block is gradually increased, so that the transmission block is driven to move towards the direction of the identification rods, and when the two identification rods swing and the swing angles are the same, the central axes of the driving rod and the drill bit and the central axis of the positioning hole are arranged in a collinear manner;

3. aim at dead lever and screw rod tip, drive thread bush and threaded rod threaded connection, the thread bush drives the joint ring and slides outside the dead lever, and moves towards butt dish direction, when joint ring and butt dish butt, under the threaded connection of thread bush and threaded rod and the effect of dragging of joint ring and butt dish, accomplishes steel reinforcement cage and construction platform's installation work.

Drawings

FIG. 1 is a flow chart of the construction of an embodiment of the present application;

FIG. 2 is a schematic diagram of the overall structure of an embodiment of the present application;

FIG. 3 is a schematic view of a positioning frame, a limiting block, a transmission block and an identification rod in the embodiment of the application;

FIG. 4 is a schematic view of the hinge shaft, the marking lever and the torsion spring in the embodiment of the present application;

FIG. 5 is a schematic view of a drill bit, a drive rod, a magnet block, a drive block, and an identification rod in an embodiment of the present application;

FIG. 6 is a schematic illustration of a reinforcement cage and a construction platform according to an embodiment of the present disclosure;

fig. 7 is an enlarged view at a in fig. 6.

Reference numerals: 1. a drill bit; 2. positioning holes; 3. positioning a rod; 4. a reinforcement cage; 5. a transmission block; 6. an identification rod; 7. a through hole; 8. hinging shafts; 9. a torsion spring; 10. a drive rod; 11. a limiting block; 12. a limiting groove; 13. a spring; 14. a magnet block; 15. a construction platform; 16. a threaded rod; 17. fixing the rod; 18. a threaded sleeve; 19. a snap ring; 20. a butting tray; 21. a positioning frame.

Detailed Description

The present application is described in further detail below with reference to figures 1-7.

The embodiment of the application discloses a construction method for rotary drilling hole-forming cast-in-place threaded piles. Referring to fig. 1 and 2, a construction method for rotary drilling hole-forming cast-in-place screw pile includes the following steps:

s1, paying off pile positions, determining the distribution and the positions of rotary-digging hole-forming pouring threaded piles, determining each parameter of each pile, lofting all the pile positions, marking the positions of pile cores by cross lines, and extending out control lines;

referring to fig. 2 and 3, S2, positioning the pile core, manually developing a positioning hole 2 at the pile core position, placing a positioning rod 3 in the positioning hole 2 to ensure that the positioning rod 3 is in a vertical state, making the positioning frame 21 frame-shaped, passing the positioning frame 21 center through the positioning rod 3, and completing the placement of the positioning frame 21 through the cooperation of the identification device and the positioning rod 3; identification means includes two driving block 5 and two sign poles 6, and two driving block 5 and two sign poles 6 set up for the symmetry along the vertical plane of symmetry of locating rack 21, and locating rack 21 is provided with two through-holes 7 along its vertical plane of symmetry, and through-hole 7 runs through the lateral wall of locating rack 21, and 5 sliding connection of driving block are in through-hole 7.

Referring to fig. 2 and 4, identification rod 6 is vertical setting, and identification rod 6 is articulated with locating rack 21, it is connected with articulated shaft 8 to rotate between identification rod 6 and the locating rack 21, the axis direction of articulated shaft 8 is the level setting, and set up along the axis direction of perpendicular to through-hole 7, the outer wall of identification rod 6 is close to the opening part in through-hole 7, the one end and the 6 outer wall butt of identification rod of driving block 5, the other end and 3 outer wall butts of locating lever, this moment, driving block 5 is driven towards the 6 direction movements of identification rod, 7 direction swings are kept away from to identification rod 6 emergence orientation, realize the swing sign effect of identification rod 6, observe two 6 wobbling angles of identification rod, ensure that the center of locating rack 21 is concentric setting with the center of locating lever 3, bury locating rack 21 in ground at last.

Referring to fig. 3 and 4, a reset part is arranged between the positioning frame 21 and the identification rod 6, the reset part is a torsion spring 9, two ends of the torsion spring 9 are respectively fixedly connected with the positioning frame 21 and the identification rod 6, when the torsion spring 9 is in an original shape, the identification rod 6 is in a vertical state, and when the transmission block 5 drives the identification rod 6 to swing, the torsion spring 9 is in a deformation state; the equal fixedly connected with stopper 11 in both sides of driving block 5, 7 inner walls of through-hole are provided with two spacing grooves 12, and the both ends of spacing groove 12 are closed setting, and stopper 11 sliding connection realizes the restriction effect to 5 direction of motion of driving block in spacing groove 12.

Spacing groove 12 is kept away from in the tip inner wall fixedly connected with spring 13 of actuating lever 10, the other end and the stopper 11 fixed connection of spring 13, when drive block 5 is driven towards the motion of 6 directions of sign pole, spring 13 is by extrusion deformation, if remove the effort of applying to drive block 5, under the effect of spring 13 and torsional spring 9, drive block 5 is close to the one end that is located through-hole 7 of sign pole 6, sign pole 6 is in vertical state, 6 tip fixedly connected with sign cloths of sign pole, sign cloth coating has red coating, promote the 6 wobbling warning effects of sign pole.

Referring to fig. 2 and 5, S3, positioning the drill bit 1, removing the positioning rod 3, installing a driving element at the center of the drill bit 1, positioning the rotary drilling position of the drill bit 1 by using the driving element and the identification device, and removing the driving element; the driving piece sets up to actuating lever 10, and the diameter of actuating lever 10 section is unchangeable after increasing gradually along 1 direction of drill bit, and the 5 tip butts of actuating lever outer wall and transmission piece, and actuating lever 10 is kept away from the one end fixedly connected with magnet piece 14 in locating rack 21, and magnet piece 14 is used for adsorbing with drill bit 1, and guarantees the outer vertical condition of actuating lever 10.

At regulation drill bit 1 in-process, control actuating lever 10 is towards the clearance motion between two drive blocks 5, actuating lever 10 outer wall and the tip butt of drive block 5, along with actuating lever 10 when the motion in towards locating hole 2, the cross-section circle diameter crescent of actuating lever 10 and the 5 butt positions of drive block, consequently, drive block 5 is driven towards the motion of 6 directions of identification lever, swing when two identification lever 6 all take place, and the swing angle is the same, the central axis of actuating lever 10 and drill bit 1 this moment is the collinear setting with the central axis of locating hole 2.

S4, embedding a pile casing, manually excavating or excavating a preset hole by using an excavator at the position to be drilled, and embedding the pile casing in the preset hole;

s5, drilling, namely, drilling by using a drilling machine, installing the drill bit 1 on an output shaft of the drilling machine, pulling out the rotary drilling drill bit 1 after the drilling depth reaches the designed pile elevation, cleaning the hole, and detecting various indexes of a pile hole, including the hole diameter, the hole depth and the perpendicularity;

s6, installing a reinforcement cage 4, manufacturing the reinforcement cage 4 from the bottom of a pile to the top of the pile in sections, and after manufacturing the reinforcement cage 4, hoisting the reinforcement cage 4 into a pile hole;

referring to fig. 6 and 7, in the grouting process, when concrete is poured to the bottom of the reinforcement cage 4, the pouring speed of the concrete is too high, and when buoyancy generated by the reinforcement cage 4 in the concrete and jacking force generated by the concrete rising are larger than the self weight of the reinforcement cage 4, the reinforcement cage 4 floats upwards, and the specific gravity of slurry is too high, so that the jacking buoyancy of the slurry is increased; in order to avoid the upward floating of the reinforcement cage 4, after the reinforcement cage 4 is installed, a construction platform 15 is fixedly installed at the top end of the reinforcement cage 4, the construction platform 15 is provided with a pouring gate for pouring concrete, the construction platform 15 is placed on the ground, a concrete pouring device in a balancing weight is placed on the construction platform 15, and downward pressure is applied to the reinforcement cage 4;

in order to facilitate the effect of installation and disassembly between the top end of the steel reinforcement cage 4 and the construction platform 15, the top end of the steel reinforcement at the top end of the steel reinforcement cage 4 is fixedly connected with a threaded rod 16, the ground of the construction platform 15 is fixedly connected with a plurality of fixing rods 17 corresponding to the threaded rod 16, threaded sleeves 18 are sleeved outside the fixing rods 17, threaded sleeves 18 are in threaded connection with the threaded rod 16, clamping assemblies are arranged between the threaded sleeves 18 and the fixing rods 17 and comprise clamping rings 19 and abutting discs 20, the clamping rings 19 are fixedly connected with one ends, facing away from the threaded rod 16, of the threaded sleeves 18, the abutting discs 20 are fixedly connected with one ends, close to the threaded rod 16, of the fixing rods 17, and the clamping rings 19 are slidably connected outside the fixing rods 17;

the end of the fixing rod 17 is aligned with the end of the threaded rod 16, the threaded sleeve 18 is driven to be in threaded connection with the threaded rod 16, the threaded sleeve 18 drives the clamping ring 19 to slide outside the fixing rod 17 and move towards the direction of the abutting disc 20, and when the clamping ring 19 abuts against the abutting disc 20, installation work of the reinforcement cage 4 and the construction platform 15 is completed under the effects of threaded connection of the threaded sleeve 18 and the threaded rod 16 and dragging of the clamping ring 19 and the abutting disc 20.

And S7, pouring concrete, pouring the concrete into the pile hole, removing the threaded rod 16 and connecting the threaded sleeve 18 after the concrete is poured, removing the construction platform 15, and completing the construction process of pouring the threaded pile after the pile is formed.

The implementation principle of the construction method for the rotary drilling hole-forming cast-in-place threaded pile in the embodiment of the application is as follows: confirm the center in stake hole site and every stake hole, set up locating hole 2 with the position of stake core, and peg graft locating lever 3 in locating hole 2, position relation through locating lever 3 and transmission piece 5, and observe the wobbling angle of marker post 6, confirm the position of locating rack 21 and locating hole 2 coaxial line, rethread actuating lever 10 is to the drive relation of transmission piece 5, accomplish the location effect of drill bit 1, dismantle actuating lever 10 and locating rack 21 back, bury the pile casing underground, drill hole to stake hole site, clear hole back installation steel reinforcement cage 4, treat steel reinforcement cage 4 and accomplish the installation back, install construction platform 15 at steel reinforcement cage 4 top, through the detachable connection relation of threaded rod 16 with thread bush 18, avoid steel reinforcement cage 4 come-up, after the concrete pouring, demolish construction platform 15, accomplish the work of pouring into screwed pile.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims (9)

1. A construction method for rotary excavating hole-forming cast-in-place screw pile is characterized in that: the method comprises the following steps:

s1, paying off pile positions, determining the distribution and the positions of rotary-drilled hole-forming cast-in-place threaded piles, determining each parameter of each pile, lofting all the pile positions, and marking the positions of pile cores by using cross lines;

s2, positioning a pile core, excavating a positioning hole (2) at the pile core position, placing a positioning rod (3) in the positioning hole (2), penetrating the positioning rod (3) through the center of a positioning frame (21), and completing placement of the positioning frame (21) through the matching action of an identification device and the positioning rod (3);

s3, positioning the drill bit (1), installing a driving piece at the center of the drill bit (1), positioning the rotary drilling position of the drill bit (1) by using the driving piece and the identification device, and detaching the driving piece;

s4, embedding a pile casing at the position to be drilled;

s5, drilling, namely drilling by using a drilling machine, pulling out the rotary drilling bit (1) after the drilling depth reaches the designed pile elevation, cleaning the hole, and detecting various indexes of the pile hole;

s6, installing the reinforcement cage (4), and hoisting the reinforcement cage (4) into the pile hole;

s7, pouring concrete, and after secondary hole cleaning, pouring the concrete into the pile hole; completing the pouring work after pile forming; the identification device comprises two transmission blocks (5) and two identification rods (6), two through holes (7) are symmetrically formed in the positioning frame (21) along the vertical symmetrical plane of the positioning frame, the transmission blocks (5) are connected in the through holes (7) in a sliding mode, one ends of the transmission blocks (5) are abutted to the identification rods (6), the other ends of the transmission blocks (5) are abutted to the outer wall of the positioning rod (3), the identification rods (6) are vertically arranged and hinged to the positioning frame (21), and reset pieces are arranged between the positioning frame (21) and the identification rods (6).

2. The construction method of the rotary excavating hole-forming cast-in-place screw pile according to claim 1, characterized by comprising the following steps: sign pole (6) with it is connected with articulated shaft (8) to rotate between locating rack (21), the axis direction of articulated shaft (8) sets up for the level, the piece that resets sets up to torsional spring (9), the both ends of torsional spring (9) respectively with sign pole (6) and fixed connection between locating rack (21).

3. The construction method of the rotary excavating hole-forming pouring threaded pile according to claim 2, characterized by comprising the following steps: the driving piece is set to be a driving rod (10), the diameter of the section circle of the driving rod (10) is unchanged after gradually increasing towards the direction of the drill bit (1), and the outer wall of the driving rod (10) is abutted to the end of the transmission block (5).

4. The construction method of the rotary excavating hole-forming cast-in-place screw pile according to claim 3, characterized by comprising the following steps: the through-hole (7) inner wall is provided with two spacing grooves (12), two stopper (11) of transmission piece (5) outer wall fixedly connected with, stopper (11) sliding connection in spacing groove (12), the both ends of spacing groove (12) are closed setting.

5. The construction method of the rotary excavating hole-forming pouring threaded pile according to claim 4, characterized by comprising the following steps: the limiting groove (12) is far away from the inner wall of the end part of the driving rod (10) and is fixedly connected with a spring (13), and the other end of the spring (13) is fixedly connected with the limiting block (11).

6. The construction method of the rotary excavating hole-forming pouring threaded pile according to claim 5, characterized by comprising the following steps: one end, far away from the positioning frame (21), of the driving rod (10) is fixedly connected with a magnet block (14) used for being adsorbed by the drill bit (1).

7. The construction method of the rotary excavating hole-forming pouring threaded pile according to claim 1, characterized by comprising the following steps: and S6, after the reinforcement cage (4) is installed, a construction platform (15) arranged on the ground is fixedly installed at the top end of the reinforcement cage (4), and a balancing weight is placed on the construction platform (15) or a concrete pouring device is poured on the construction platform.

8. The construction method of the rotary excavating hole-forming pouring threaded pile according to claim 7, characterized by comprising the following steps: reinforcing bar top fixedly connected with threaded rod (16) of steel reinforcement cage (4), construction platform (15) bottom surface fixedly connected with a plurality of with dead lever (17) that threaded rod (16) correspond, dead lever (17) overcoat is equipped with thread bush (18), thread bush (18) with threaded rod (16) threaded connection, thread bush (18) with be provided with the joint subassembly between dead lever (17).

9. The construction method of the rotary excavating hole-forming pouring threaded pile according to claim 8, characterized by comprising the following steps: the joint subassembly includes joint ring (19) and butt dish (20), joint ring (19) with thread bush (18) keep away from in the one end fixed connection of threaded rod (16), butt dish (20) with dead lever (17) are close to in the one end fixed connection of threaded rod (16), joint ring (19) with butt dish (20) butt.

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