Bolt with self-adaptive fastening torque

Abstract

The utility model belongs to the technical field of petrochemical equipment, and particularly discloses a self-adaptive fastening torque bolt, the top surface of a shell is a second end surface connected with a mechanism to be jacked, a cavity is arranged between the shell and a gland, a piston is arranged in the cavity and is connected with the inner wall of the cavity in a sliding manner, and the piston is connected with the second end surface of the shell. A spring assembly is arranged between the piston and the top wall of the cavity, a connecting handle extending towards the gland is arranged in the center of the bottom of the piston, and the connecting handle penetrates through a through hole formed in the middle of the gland and extends downwards to form a first end face connected with a to-be-jacked mechanism. The bottom of the piston, the top of the gland and the inner side wall of the shell jointly define a closed pressure cavity, and under the action of the driving mechanism, the piston can move up and down to adjust the distance between the first end face and the second end face so that the jacking force between the first end face and the second end face can be kept balanced. Fastening failure caused by stress change at the connecting face can be effectively avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of petrochemical equipment, and particularly discloses a bolt with self-adaptive tightening torque. Background Art

[0002] As is known to all, in the petrochemical equipment manufacturing industry, pipe flanges, valves and other equipment are usually fastened with bolts. After pre-tightening with ordinary bolts, the pre-tightening force is fixed unless pre-tightened again. Some pipes, valves and other equipment have special working conditions such as alternating hot and cold temperatures with large temperature differences due to the working medium. At this time, the fastening force of ordinary bolt connections will deteriorate or fail due to the alternating hot and cold temperatures, and frequent pre-tightening is required, which results in a large maintenance workload for the equipment and may even cause leakage of high-temperature, toxic and other media, posing a greater safety hazard. Summary of the Invention

[0003] In order to solve the problems in the background technology, the utility model discloses a bolt with adaptive tightening torque. Under the action of a driving mechanism, the piston can move up and down to adjust the distance between the first end face and the second end face, ensuring that the torque of the bolt after tightening will not change due to external influences.

[0004] In order to achieve the above-mentioned purpose of the invention, the present invention adopts the following technical solutions:

[0005] The cam is secured to the upper edge of the second support frame, and the cam is secured to the lower edge of the second support frame by a spring.

[0006] Furthermore, the bolt with adaptive tightening torque is provided with support limit blocks at intervals above and below in the middle of the spring assembly, and the support limit blocks together form an I-shaped support limit seat. The spring assembly is sleeved on the support limit seat, and the two ends of the support limit seat are respectively in tight contact with the top wall of the cavity and the top of the piston, and a through hole is provided in the middle of the support limit seat at a position corresponding to the screw hole.

[0007] Furthermore, the bolt with adaptive tightening torque, the piston and the connecting handle are integrally formed.

[0008] Furthermore, the bolt with adaptive tightening torque is embedded with a plurality of sealing members A at intervals along the axial direction of the screw hole on the contact surface between the piston and the inner wall of the cavity.

[0009] Furthermore, the bolt with adaptive tightening torque has a plurality of sealing members B embedded at intervals along the axial direction of the screw hole on the contact surface between the connecting handle and the gland.

[0010] Furthermore, the bolt with adaptive tightening torque is provided with a step surface on the top edge of the gland, the shell fits on the step surface, the shell and the step surface are fixedly connected by the gland bolts, and a seal C is provided on the contact surface between the shell and the step surface.

[0011] Compared with the prior art, the beneficial effects of the present invention are:

[0012] The cam is provided with a first end face that is fixed with the cam frame, and a second end face that is fixed with the cam frame, and a second end face that is fixed with the cam frame, wherein the cam frame is provided with a first end face that is fixed with the cam frame, and a second end face that is fixed with the cam frame is provided with a second end face that is fixed with the cam frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic cross-sectional view of the spring-loaded mechanism of the utility model that is easy to adjust;

[0014] In the above figure: 1-housing; 2-spring assembly; 3-support limit block; 4-piston; 5-seal A; 6-pressure cover; 7-inlet and outlet channels; 8-screw hole; 9-first end face; 10-pressure cover bolt; 11-seal B; 12-seal C; 13-pressure chamber; 14-second end face. DETAILED DESCRIPTION

[0015] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0016] Combined with attachment Figure 1 , the utility model is described in detail. A bolt with adaptive tightening torque comprises a shell 1, a piston 4 and a pressure cover 6 arranged in sequence from top to bottom. The shell 1 is buckled on the pressure cover 6. The top surface of the shell 1 is a second end surface 14 connected to the mechanism to be tightened. A cavity is provided between the shell 1 and the pressure cover 6. The piston 4 is provided in the cavity and is slidably connected to the inner wall of the cavity. A spring assembly 2 is provided between the piston 4 and the top wall of the cavity. A connecting handle extending toward the pressure cover 6 is provided at the bottom center of the piston 4. The connecting handle extends downward through a through hole provided in the middle of the pressure cover 6 to form a first end surface 9 connected to the mechanism to be tightened. 4 and the middle of the connecting handle are provided with a coaxially arranged screw hole 8, the bottom of the piston 4, the top of the pressure cover 6 and the inner wall of the shell 1 together form a closed pressure chamber 13, and the pressure cover 6 is provided with an inlet and outlet channel 7 running through its upper and lower end faces, one end of the inlet and outlet channel 7 is connected to the pressure chamber 13, and the other end is connected to the driving mechanism. Under the action of the driving mechanism, the piston 4 can move up and down to adjust the distance between the first end face 9 and the second end face 14. It should be noted here that it is preferred that a detection tool for online detection of the pressure of the pressure chamber 13 is provided on the connecting pipe between the inlet and outlet channel 7 and the driving mechanism. The detection tool detects the pressure of the pressure chamber 13 and sends the detection signal to the control system. As a result, the detection tool can be a pressure gauge. The detection tool and the control system are not the innovative points of the invention, so they are not described in detail. When working, the utility model is used for connecting and fastening some pipes, valves and other equipment. The gland 6 is connected to the housing 1 through the gland bolt 10. The housing 1 and the piston 4 are respectively connected with the screw threaded through the screw hole 8. The first end face 9 and the second end face 14 are respectively connected to the mechanism to be tightened. The required tightening force is achieved by setting the preload of the spring assembly 2. The driving mechanism applies hydraulic pressure or air pressure to the pressure chamber 13 through the inlet and outlet channel 7. Under the joint action of the piston 4 and the spring assembly 2, a pressure is provided between the first end face 9 and the second end face 14. The continuous and easily adjustable tightening load ensures that the distance between the first end face 9 and the second end face 14 is fixed, and the tightening force is fixed and continuous. When the tightened mechanism connection is displaced due to alternating hot and cold, the distance between the first end face 9 and the second end face 14 changes. The driving mechanism applies pressure to the pressure chamber 13 through the inlet and outlet channel 7, which can be air pressure or hydraulic pressure, to push the piston 4 to adjust the preload of the spring group 2, so that the tightening force between the first end face 9 and the second end face 14 remains balanced. In particular, it can provide continuous and easily adjustable tightening force under special working conditions such as alternating hot and cold with a large temperature difference. It is easy to use and can effectively avoid tightening failure caused by stress changes at the connection surface.

[0017] As an optional design, the bolt with adaptive tightening torque is preferably provided with support limit blocks 3 at upper and lower intervals in the middle of the spring assembly 2, and the support limit blocks 3 together form an I-shaped support limit seat, and the spring assembly 2 is sleeved on the support limit seat, and the two ends of the support limit seat are respectively in tight contact with the top wall of the cavity and the top of the piston 4. A through hole is provided in the middle of the support limit seat at a position corresponding to the screw hole 8. Under the action of the piston 4, the two support limit blocks 3 are forced to compress the spring assembly 2 to adjust the compression amount of the spring assembly 2.

[0018] As an optional design, the bolt with adaptive tightening torque is preferably formed in one piece with the piston 4 and the connecting handle. Under the combined action of the pressure in the pressure chamber 13 and the spring assembly 2, the piston 4 is forced to move to achieve the purpose of adjusting the tightening force between the first end face 9 and the second end face 14.

[0019] As an optional design, the bolt with adaptive tightening torque is preferably embedded with a plurality of seals A5 at axial intervals along the screw hole 8 on the contact surface between the piston 4 and the inner wall of the cavity to ensure the airtightness of the pressure chamber 13.

[0020] As an optional design, the bolt with adaptive tightening torque is preferably embedded with a plurality of seals B11 at axial intervals along the screw hole 8 on the contact surface between the connecting handle and the pressure cover 6 to ensure the airtightness of the pressure chamber 13.

[0021] As an optional design, the bolt with adaptive tightening torque is preferably provided with a step surface on the top edge of the pressure cover 6, the shell 1 fits on the step surface, the shell 1 and the step surface are fixedly connected by the pressure cover bolt 10, and a seal C12 is provided on the contact surface between the shell 1 and the step surface to ensure the air tightness of the pressure chamber 13.

[0022] The working process of this utility model is as follows:

[0023] During operation, the utility model is used for fastening the connection of some pipes, valves and other equipment. The gland 6 is connected to the housing 1 through the gland bolt 10. The housing 1 and the piston 4 are respectively connected with the screw threadedly provided in the screw hole 8. The first end face 9 and the second end face 14 are respectively connected to the mechanism to be tightened. The required tightening force is achieved by setting the preload of the spring assembly 2. When the connection of the tightened mechanism is displaced due to alternating hot and cold, the tightening force between the first end face 9 and the second end face 14 changes, and the driving mechanism applies liquid to the pressure chamber 13 through the inlet and outlet channel 7. Pressure or air pressure is used to push the piston 4 to adjust the preload of the spring assembly 2. Under the joint action of the piston 4 and the spring assembly 2, a continuous tightening load is provided between the first end face 9 and the second end face 14, so that the tightening force between the first end face 9 and the second end face 14 is balanced, ensuring that the distance between the first end face 9 and the second end face 14 is fixed, and the tightening force is fixed and continuous. In particular, under special working conditions such as alternating hot and cold with a large temperature difference, a continuous and easily adjustable tightening force can be provided. The method is easy to use and can effectively avoid tightening failure caused by stress changes at the connection surface.

[0024] The above description is only an application implementation method of the present utility model, but the protection scope of the present utility model is not limited to this, and the scope of rights of the present utility model cannot be limited by this. Any equivalent changes made according to the technical solution of the present utility model should be included in the protection scope of the present utility model.

Claims

1. A bolt with adaptive tightening torque, characterized by: The cam is secured to the upper and lower ends of the cam, and the cam is secured to the bottom of the cam by a spring which is secured to the bottom ends of the cams. The cams are secured to the lower ends of the cams by a spring which is secured to the bottom ends of the cams.

2. The bolt with adaptive tightening torque according to claim 1, characterized in that: Support limit blocks are arranged at intervals in the upper and lower parts of the middle part of the spring assembly, and the support limit blocks together form an I-shaped support limit seat. The spring assembly is sleeved on the support limit seat, and the two ends of the support limit seat are in tight contact with the top wall of the cavity and the top of the piston respectively. A through hole is provided in the middle part of the support limit seat at a position corresponding to the screw hole.

3. The bolt with adaptive tightening torque according to claim 1 or 2, characterized in that: The piston and the connecting handle are integrally formed.

4. The bolt with adaptive tightening torque according to claim 1, characterized in that: A plurality of seals A are embedded at intervals along the axial direction of the screw hole on the contact surface between the piston and the inner wall of the cavity.

5. The bolt with adaptive tightening torque according to claim 1, characterized in that: A plurality of sealing members B are embedded at intervals along the axial direction of the screw hole on the contact surface between the connecting handle and the gland.

6. The bolt with adaptive tightening torque according to claim 1, characterized in that: The top edge of the gland is provided with a step surface, the shell is fitted on the step surface, the shell and the step surface are fixedly connected by gland bolts, and a seal C is provided on the contact surface between the shell and the step surface.

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