CN106837980B

CN106837980B - Combined self-reaction anti-loose nut with high-precision torque coefficient

Info

Publication number: CN106837980B
Application number: CN201610246658.XA
Authority: CN
Inventors: 李圣用
Original assignee: Individual
Current assignee: Beikou Shanghai Technology Development And Operation Center
Priority date: 2016-04-20
Filing date: 2016-04-20
Publication date: 2020-02-07
Anticipated expiration: 2036-04-20
Also published as: CN106837980A

Abstract

The invention relates to a combined self-reaction anti-loose nut with high-precision torque coefficient, which comprises a slotted nut, a washer and a threaded ring. When the working bolt is in a tightened state, the threaded ring is inlaid between the washer and the bolt in a wedge-shaped ring mode, and connection between the working bolt and the nut is effectively prevented from loosening. The invention enables the bolt and nut in the mechanical industry to be connected and installed under the level with smaller friction coefficient to obtain accurate bolt pretightening force, and the anti-loosening function is always kept in the running process of equipment. The invention greatly increases the reliability and safety of bolt and nut connection in the mechanical industry, particularly in the equipment operation process of industries such as petroleum and petrochemical industry, power generation, offshore wind power, nuclear power, high-speed rail, bridge and the like, thereby greatly reducing the frequency of manual point inspection and maintenance of the bolt and nut. The scale popularization and application of the invention can generate unlimited economic value.

Description

Combined self-reaction anti-loose nut with high-precision torque coefficient

Technical Field

The invention relates to a combined self-reaction anti-loose nut with high-precision torque coefficient, which comprises a slotted nut, a washer, a threaded ring and the like.

Background

Many heavy equipment in the mechanical industry are connected by bolts for convenient disassembly and maintenance during design. The bolt and the nut can play a role in connection and fastening, and friction force exists between threads of the bolt and the nut and between the nut and an equipment part so as to prevent the nut from loosening. People often achieve the purpose of looseness prevention by increasing the friction coefficient of the bolt and the nut. Some anti-loose bolt and nut products (such as sawtooth nuts, nylon nuts, double sawtooth gaskets and the like) increase friction coefficients on the aspect of structural design, the torque coefficients are very large, and the anti-loose bolt and nut products are screwed under the condition of the same torque, because the friction coefficient error accounts for a large proportion, the pretightening force error of the bolt is very large, the pretightening force deviation of different bolts of the same part is very large, and the connection reliability of equipment is reduced due to the fact that the pretightening force is not uniform; some manufacturers (such as locking glue, a hole-forming bolt, electric welding, thread breakage and the like) increase the friction coefficient after the bolt is screwed down, so that the bolt and the nut cannot be checked and known if the bolt and the nut are loosened after the equipment runs, and the operation of supplementing the pretightening force of the loosened bolt cannot be performed. In a word, if the bolt and nut pretightening force is required to be accurate, people usually adopt a method for reducing the friction coefficient and improving the torque coefficient; meanwhile, people hope to improve the anti-loosening function of the bolt and the nut, and need to adopt a method for improving the friction coefficient and reducing the torque coefficient. The requirement of accurate pretightening force and looseness prevention of the bolt and the nut are always a pair of spear bodies, and no one provides a truly feasible solution in hundreds of years of modern industrial development.

Most bolted connections are currently tightened using a torque tightening method. The torque tightening method is to rotate a nut by using a torque tool, and to cause the bolt to be forced to stretch and generate elastic deformation through the relative displacement between the threads of the nut and the bolt, so that the bolt generates rebound pretightening force. Because the friction coefficients between the nuts positioned at different positions of the same part and the basic surface of a component (such as a flange or an equipment body) are different, the same torque acting on the nuts cannot obtain the same elastic deformation of the bolts, and the torque is converted into the bolt pretightening force to be different; in the process of screwing the nut by a torque method, a reaction torque is required to be applied while an action torque is applied, and the reaction force generally acts on a fulcrum of a bolt accessory to cause the bolt to deflect and cause unbalance loading by depending on the edge of a threaded hole; under the condition that the nut is screwed, the torque of the nut is transmitted to the bolt, and the other side of the bolt leans against the friction coefficient of the head of the screw or the back force of the supporting wrench, so that the bolt cannot rotate, and the bolt generates integral torsional shear stress.

In the actual operation process, under the working conditions of vibration, temperature difference, pressure difference and the like, bolts and nuts which have inaccurate pretightening force and integral torsional shear stress or are connected by bolts of mechanical equipment parts with small friction coefficients can be loosened. The pretightening force of the bolt cannot always meet the requirements of the original mechanical equipment in industrial design, and serious production safety accidents such as collapse of large-scale equipment, gas leakage and oil leakage of petroleum and petrochemical equipment and the like can occur. In order to improve the operation safety of equipment, an enterprise generally adopts a method that a professional mechanical engineer is sent to bring a professional bolt tightening device (bolt torque tightening device) periodically (every week, three months, half a year or one year), and related bolts and nuts are checked one by one, wherein the inspection is called bolt loosening scheduled inspection in the industry. In the regular inspection work of the equipment bolt, whether the bolt is loosened or not is checked, and a great deal of time is required for an engineer. In order to ensure the safety of the engineer during the operation, the equipment must be stopped during the bolt checking work, which reduces the yield of the equipment and causes loss. Enterprises spend enormous expenses on regular bolt pre-tightening force inspection and maintenance work every year, on manpower, purchasing or leasing equipment for inspecting whether bolts are loosened, and on yield reduction caused by machine halt.

The problem of ensuring that the bolted connection is accurately tightened and has a function of preventing loosening has become a bottleneck in the development of heavy equipment, seriously affecting its ability to develop to a higher level.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides the combined self-reaction locknut with high precision torque coefficient. By using the combined self-reaction anti-loose nut, a user can realize that the bolt and the nut can obtain accurate pretightening force under the condition of high-precision torque coefficient and tightening by a torque method by using a self washer as a reaction fulcrum; in the process of screwing the working bolt, the rough lower surface of the gasket is meshed with the connected equipment part, and cannot rotate relatively; when the slotted nut is screwed up by a torque method, the action torque and the reaction torque are ensured to work in a coaxial state by taking a washer which does not rotate per se as a reaction fulcrum, and the bolt is ensured to be positioned in the center of the bolt hole instead of leaning against one side of the bolt hole in the screwing process; in the process of screwing the working bolt, the threaded ring is matched with the spline of the washer which does not rotate, so that the threaded ring cannot rotate and can only move upwards along the spline of the washer, and the integral shearing stress of the bolt cannot be ensured in the process of screwing; when the working bolt is in a tightened state, the threaded ring is inlaid between the washer and the bolt in a wedge-shaped ring mode, and connection between the working bolt and the nut is effectively prevented from loosening.

The specific technical scheme is as follows:

a combined self-reaction locknut with high-precision torque coefficient comprises a slotted nut, a washer and a threaded ring in sequence;

the slotted nut is a round slotted nut or a six-slotted-angle nut, the inside of the slotted nut is provided with internal threads, and the bottom of the slotted nut is provided with a smooth surface;

the washer is in a dodecagonal or hexagonal shape which can be clamped and held by a counterforce component, a 0-10-degree conical spline is arranged in the washer, the top of the washer is a smooth surface, and the bottom of the washer is a rough anti-skidding surface;

the external part of the threaded ring is provided with a fine spline, and the internal part is an internal thread.

The angle of the tapered spline inside the washer is not 0.

The smooth surface at the top of the washer is in contact fit with the smooth surface at the bottom of the slotted nut, and the friction coefficient is less than 0.15 and uniform when the slotted nut rotates.

The tapered spline inside the washer is matched with the fine spline outside the threaded ring, a taper deviation larger than 0 degree is generated after the working bolt is screwed, and the threaded ring is embedded between the washer and the working bolt in a wedge-shaped ring mode to play a role in preventing the bolt and the nut from being connected.

Under the torque action of a torque tightening method, the slotted nut moves relatively, the bolt deforms elastically, when the bolt is under stress, the anti-skid end face teeth at the bottom of the gasket are meshed with the basic surface of a relevant part (a flange or other parts needing to be connected) of equipment, so that the relevant part cannot rotate relatively, the smooth surface at the other end of the gasket is contacted with the smooth bottom surface of the nut, the friction coefficient between the nut and the gasket is relatively small and uniform, and the bolt is enabled to obtain accurate pretightening force; because the anti-skidding end face teeth at the bottom of the washer are meshed with related parts (flanges or bearing rings or other parts needing to be connected) of equipment and cannot rotate, and the threaded rings are matched with the washer through the internal splines and the external splines, the threaded rings cannot rotate mutually and can only slide up and down along the internal splines of the washer. The bolt is matched with the threaded ring through threads, when the bolt is screwed down by the nut, the threaded ring cannot rotate, the bolt cannot rotate due to the fact that the threaded ring is forced, and the bolt can only be pulled upwards by the nut to move, so that integral torsional stress cannot be generated in the process that the bolt is screwed down; after the nut is screwed down, the taper deviation between the threaded ring and the washer enables the threaded ring to be inlaid between the washer and the bolt in a wedge-shaped ring mode, and the effect of effectively preventing the connection between the working bolt and the nut from loosening is achieved.

The invention has the beneficial effects that: through the mechanical structure design, the bolt of the mechanical equipment obtains accurate pretightening force through a traditional torque tightening method, the bolt does not have integral shearing stress after being tightened, and the super-strong anti-loosening function is realized; the bolt pre-tightening force is accurate, integral torsional shear stress does not exist, and the bolt pre-tightening force has an ultra-strong anti-loosening function, so that the failure of mechanical equipment due to loosening of the bolt connection pre-tightening force is comprehensively reduced, the manual maintenance frequency of the mechanical equipment bolt is reduced, the cost of periodic maintenance of the mechanical equipment bolt is reduced, the effective production time of the equipment is prolonged, and the operation reliability and the safety of the mechanical equipment are improved.

Drawings

Fig. 1 is an exploded schematic view of a combined self-reaction locknut of embodiment 1;

FIG. 2 is an assembly view of embodiment 1;

FIG. 3 is a sectional view of embodiment 1;

FIG. 4 is a schematic view of the bottom tooth form of the gasket of embodiment 1;

FIG. 5 is a sectional view of a bolt connection of embodiment 1;

fig. 6 is an exploded view of the bolt connection of embodiment 1.

FIG. 7 is a partial sectional view showing the mounting method of embodiment 1;

fig. 8 is a schematic view of the antitheft mode according to embodiment 1.

Description of the symbols:

1, slotting a nut; 2, a gasket; 3, a threaded ring;

4. 5 basic parts (flanges or other parts needing connection) of mechanical equipment;

6, working bolts; 7 a castle action torque sleeve; an 8-sided reaction torque sleeve.

Detailed Description

The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings, but the scope of the invention should not be limited thereto.

Example 1

Please refer to fig. 1, which is an exploded schematic view of the combined self-reaction locknut with high precision torque coefficient of the present embodiment, including a slotted nut 1, a washer 2 with tapered internal splines, and a threaded ring 3 with common internal threads and fine external splines, which is matched with the washer 2.

In the embodiment, the contact surface of the slotted nut 1 and the washer 2 with the taper internal spline is a finish-machined smooth surface, so that the friction coefficient between binding surfaces cannot be changed too much to influence the tensile deformation precision of the bolt under the action of the same torque; the bottom of the washer 2 is provided with rough anti-slip threads, in this embodiment, the serrated anti-slip threads, as shown in fig. 4, the multi-tooth-shaped bottom surface is in contact with the surface of the base part 4 of the mechanical device when the bolt is fastened, so as to increase the friction coefficient between the washer 2 with the tapered internal splines and the contact surface of the base part 4 of the mechanical device, and ensure that the washer 2 cannot rotate during the nut tightening process.

Referring to the sectional view of fig. 5, as shown, the working bolt 6 passes through the connecting hole of the mechanical equipment base part 5 and the mechanical equipment base part 4 to connect them; the tail part provided with the threads is mutually meshed and connected with the internal threads of the slotted nut 1 containing the internal threads and the threaded ring 3 containing the common internal threads and the tiny external splines of the combined self-reaction anti-loose nut of the embodiment; the lower surface of the washer 2 with the internal spline, which is provided with the sawtooth type anti-skid grains, is attached to a basic part 4 of mechanical equipment; the outer side of the washer 2 with the taper internal spline is further matched with a multi-edge reaction torque sleeve 8 to be held to play a role of a self-reaction fulcrum; after the force application torque acts through the acting torque castle sleeve 7, the slotted nut 1 with the internal thread rotates; the slotted nut 1 containing the internal thread drives the working bolt 6 to generate relative movement; the bolt 6 drives the threaded ring 3 to slide upwards along the internal spline of the gasket 2; the working bolt 6 generates pre-tightening force after generating elastic deformation, and effectively connects the mechanical equipment basic component 5 and the mechanical equipment basic component 4 together; the thread ring 3 forms a wedge-shaped ring which is inlaid between the gasket 2 and the bolt 6, so that the pretightening force of the bolt is kept, and the anti-loosening effect is achieved.

In addition, the shape of the groove of the slotted nut can be deformed as shown in fig. 8, and the counterclockwise groove is angled, so that a common six-claw wrench can slide upwards under the condition of stress, and the anti-theft effect can be effectively achieved.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. It will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention, and therefore, the scope of the invention is to be determined by the appended claims.

Claims

1. A combined self-reaction locknut with high-precision torque coefficient is characterized in that the combined self-reaction locknut sequentially comprises a slotted nut, a washer and a threaded ring;

the slotted nut is a round slotted nut or a hexagonal slotted nut, the inside of the slotted nut is provided with internal threads, and the bottom of the slotted nut is provided with a smooth surface;

the washer is in a dodecagonal or hexagonal shape which can be clamped and held by a counterforce component, a conical spline which is larger than zero and less than or equal to ten degrees is arranged in the washer, the top of the washer is a smooth surface, and the bottom of the washer is a rough anti-skid surface;

the outer part of the threaded ring is provided with a fine spline, and the inner part of the threaded ring is provided with an internal thread;

the tapered spline inside the washer is matched with the fine spline outside the threaded ring, a taper deviation is generated after the working bolt is screwed down, and the threaded ring is embedded between the washer and the working bolt in a wedge-shaped ring mode.

2. The composite self-reaction anti-loose nut with high precision torque coefficient as claimed in claim 1, wherein the smooth surface of the top of the washer is in contact fit with the smooth surface of the bottom of the slotted nut, and the friction coefficient is less than 0.15 and uniform when the slotted nut rotates.