A ferrule connector with reduced and stabilized installation torque

Abstract

The application provides a sleeve joint with reduced and stable installation torque, comprising a joint body, a front sleeve, a rear sleeve and a nut, the joint body has a central hole and a tapered opening, the front sleeve has a tapered first front end and a first rear end with a tapered groove, the rear sleeve has a second tapered front end and a second rear end, the second rear end is provided with a pressure bearing surface, the nut is threadedly engaged on the joint body, the nut is provided with a driving surface, the included angle of the pressure bearing surface and the driving surface is the same, the included angle of the driving surface has an up-down deviation of x1 and y1, the included angle of the pressure bearing surface has an up-down deviation of x2 and y2, the x1, y1, x2 and y2 satisfy the following linear relationship: y2 < y1. By controlling the up-down deviation of the included angle of the pressure bearing surface of the sleeve and the driving surface of the nut, the installation torque is effectively reduced and stabilized, the installation efficiency is improved, the installation performance of the joint is improved, and the damage rate of the joint is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of installation connection of the union joint, in particular to a union joint with reduced and stable installation torque. BACKGROUND

[0002] The union joint is mainly composed of a joint body, a sleeve (single sleeve or double sleeve) and a nut. The union joint is widely used in the pipeline of automatic control device of oil refining, chemical industry, petroleum, natural gas, food, pharmaceutical and instrument system due to its high pressure resistance, reliable connection, good sealing, convenient installation and maintenance and other characteristics.

[0003] The union joint is sealed and connected by the meshing of the joint body and the nut, the movement of the nut pushing the sleeve, and the clamping of the front end of the sleeve to the pipe. Currently, the union joint is installed by the "fixed number of turns" method, that is, the pipe is inserted into the union joint, the nut is tightened by hand, a straight line is drawn on the nut and the joint body, and the nut is tightened by the wrench according to the specified number of turns. However, due to the uncertainty in the process of raw material, processing and manufacturing, surface treatment and other processes, a large number of practices show that the installation torque of the union joint with the same specification varies to a certain extent. Taking a 3 / 8 inch double sleeve joint as an example, the installation torque varies in the range of 60-85 N.M, and the variation amplitude reaches 25 N.M. Reducing and stabilizing the installation torque is of great significance to improve the installation performance, improve the installation efficiency, and reduce the damage rate of the joint. SUMMARY

[0004] The purpose of the present application is to provide a union joint with reduced and stable installation torque, which solves the problem of large variation amplitude and instability of the installation torque of the union joint as pointed out in the background.

[0005] To achieve the above object, the present application provides a technical scheme of double-cartridge joint connection: comprising a joint body, a front cartridge, a rear cartridge and a nut, the joint body has a central hole and a tapered opening at one end, the central hole and the tapered opening define a top abutting part for accommodating the end of a pipe, the front cartridge has a ring shape, a tapered first front end entering the tapered opening of the joint body and a radially increased first rear end with a tapered groove, a middle part between the tapered first front end and the first rear end has a substantially uniform wall thickness, the rear cartridge has a second tapered front end entering the tapered groove of the first rear end of the front cartridge and a radially increased second rear end, a pressure bearing surface is arranged on the second rear end, the nut is threadedly engaged with the joint body, the nut is provided with a driving surface, during tightening of the nut and the joint body, the driving surface presses the pressure bearing surface, the included angle of the pressure bearing surface and the driving surface is the same, the upper and lower deviation of the included angle of the driving surface is x1, y1, the upper and lower deviation of the included angle of the pressure bearing surface is x2, y2, the x1, y1 and x2, y2 satisfy the following linear relationship: wherein y2 < y1.

[0006] The present application also provides a technical scheme for single-cartridge joint connection: comprising a joint body, a cartridge and a nut, the joint body has a central hole and a tapered opening at one end, the central hole and the tapered opening define a top abutting part for accommodating the end of a pipe, the cartridge has a ring shape, a tapered front end entering the tapered opening of the joint body and a radially increased rear end, a middle part between the tapered front end and the rear end has a substantially uniform wall thickness, a pressure bearing surface is arranged on the rear end, the nut is threadedly engaged with the joint body, the nut is provided with a driving surface, during tightening of the nut and the joint body, the driving surface presses the pressure bearing surface, the included angle of the pressure bearing surface and the driving surface is the same, the upper and lower deviation of the included angle of the driving surface is x1, y1, the upper and lower deviation of the included angle of the pressure bearing surface is x2, y2, the x1, y1 and x2, y2 satisfy the following linear relationship: wherein y2 < y1.

[0007] Compared with the prior art, the present application has the beneficial effects that: by controlling the upper and lower deviation of the angle of the pressure bearing surface of the rear end of the cartridge and the driving surface of the nut, the acting point between the driving surface and the pressure bearing surface is stabilized at the optimal position during tightening of the joint, the installation torque is effectively reduced and stabilized, the installation efficiency is improved, the installation performance of the joint is improved, and the damage rate of the joint is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 is a disassembled schematic view of a double-cartridge joint containing the concept of the present application;

[0009] Figure 2This is a schematic diagram of the structure of the rear ferrule incorporating the concept of this invention;

[0010] Figure 3 This is a schematic diagram of the structure of a nut incorporating the concept of this invention;

[0011] Figure 4 A schematic diagram of the structure of the double ferrule connector incorporating the concept of this invention before installation;

[0012] Figure 5 for Figure 4 Enlarged view of a portion of point A in the middle;

[0013] Figure 6 A schematic diagram of the structure of the double ferrule connector incorporating the concept of this invention after installation;

[0014] Figure 7 for Figure 6 Enlarged view of a section at point B in the middle;

[0015] Figure 8 This is a schematic diagram of the double ferrule connector before and after installation, showing the state where the point of action between the nut driving surface and the rear ferrule bearing surface is slightly upward;

[0016] Figure 9 for Figure 8 Enlarged view of a section at point C;

[0017] Figure 10 This is a schematic diagram of the double ferrule connector before and after installation, showing the state where the point of action between the nut driving surface and the rear ferrule bearing surface is lower than the original.

[0018] Figure 11 for Figure 10 Enlarged view of a section at point D;

[0019] Figure 12 This is a schematic diagram of the structure of a double ferrule connector before installation, which incorporates another preferred embodiment of the present invention.

[0020] Figure 13 This is a schematic diagram of another preferred structure of the rear sleeve incorporating the concept of the present invention;

[0021] Figure 14 A schematic diagram of the structure of the single ferrule connector incorporating the concept of this invention before installation;

[0022] Figure 15 This is a schematic diagram of a single card sleeve structure incorporating the concept of this invention;

[0023] Figure 16 This is a schematic diagram of the structure of a single ferrule connector before installation, which incorporates another preferred embodiment of the present invention.

[0024] Figure 17 This is a schematic diagram of another preferred structure of a single card sleeve incorporating the concept of the present invention. DETAILED DESCRIPTION

[0025] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents the selected embodiments of the application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative work fall within the scope of the present application.

[0027] It should be noted that: similar reference numerals and letters in the following drawings represent similar items, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0028] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly used when the application is used, and are merely for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0029] In addition, the terms "horizontal", "vertical" and the like do not mean that the components must be absolutely horizontal or vertical, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0030] In the description of the present application, it should also be noted that unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] Some embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0032] Example 1

[0033] like Figures 1-7 As shown, the ferrule connector of this embodiment includes a connector body 1, a front ferrule 2, a rear ferrule 3, and a nut 4. The connector body 1 has a columnar central hole 10 and a tapered opening 12 adjacent to the central hole 10. The central hole 10 and the tapered opening 12 define an abutment 15 that can accommodate the end of the tube 5. There is a horizontal guide hole 11 between the abutment 15 and the tapered opening 12. The guide hole 11 can guide and center the inserted tube 5. The tapered opening 12 is adjacent to a female thread 13.

[0034] The front ferrule 2 is annular, with a tapered first front end 21 and a radially enlarging first rear end 23. The tapered first front end 21 can enter the tapered opening 12 of the connector body 1. There is a middle section 22 with basically the same wall thickness between the tapered first front end 21 and the second rear end 23. The second rear end 23 is provided with a tapered groove 24 that gradually narrows inward. The rear ferrule 3 is also annular, with a tapered second front end 31 and a radially enlarging second rear end 32. A pressure-bearing surface 33 is provided on the second rear end 32, and the pressure-bearing surface 33 is inclined toward the tapered second front end 31. The nut 4 is provided with a male thread 43 that engages with the connector body 1. The end of the male thread 43 is provided with a driving surface 41 at the same angle as the pressure-bearing surface 33 of the rear ferrule 3. When nut 4 is tightened with connector body 1, the driving surface 41 of nut 4 presses against the bearing surface 33 of rear ferrule 3. Nut 4 pushes the tapered second front end 31 of rear ferrule 3 into the tapered groove 24 of front ferrule 2. Rear ferrule 3 axially pushes the tapered first front end 21 of front ferrule 2 into the tapered opening 12 of connector body 1. As nut 4 further engages with connector body 2, front ferrule 2 and rear ferrule 3 deform successively, thereby clamping pipe 5 and achieving a sealed connection.

[0035] A nose 26 may also be provided on the conical first front end 21 of the front ferrule 2. Before the connector is tightened, the nose 26 is in line contact with the conical opening 12 of the connector body 1. The nose 26 can guide the conical first front end 21 of the front ferrule 2 into the conical opening 12 of the connector body 1 and provide space for radial deformation of the front ferrule 2 during the tightening of the connector. In order to facilitate the front ferrule 2 to clamp the tube 5, a cutting edge 25 may be provided on the inner wall of the front ferrule 2. The cutting edge 25 is located below the nose 26. The cutting edge 25 helps the conical first front end 21 of the front ferrule 2 to bite into the tube 5 when it deforms radially downward, forming a tight seal with the tube wall.

[0036] The driving surface 41 of nut 4 and the bearing surface 33 of rear sleeve 3 have the same included angle α, as detailed in the appendix. Figures 2-3 The included angle formed by the driving surface 41 of nut 4 is The included angle formed by the bearing surface 33 of the rear ferrule 3 is x1, y1 and x2, y2 satisfy the following linear relationship: wherein y2 < y1. The included angle a is preferably between 145° and 155°. When the upper and lower deviations of the included angle a satisfy the above linear relationship, the installation torque of the sleeve joint can be effectively reduced and stabilized within an allowable fluctuation range.

[0037] Taking a double sleeve joint of 3 / 8" specification as an example, the test results of the upper and lower deviations of the included angle a and the installation torque of the joint are as follows:

[0038]

[0039] The test results of the first group are undesirable, in which the upper and lower deviations x1, y1 of the included angle a of the rear sleeve pressure surface 33 and the upper and lower deviations x2, y2 of the included angle a of the nut driving surface 41 do not satisfy the linear relationship y2 < y1. Therefore, it is reflected that the action point F between the nut driving surface 41 and the rear sleeve pressure surface 33 during tightening of the joint is deviated upward, as shown in the accompanying drawings, which results in that the front end of the rear sleeve 3 is cut into the pipe 5 in advance before the front sleeve 2 is fully deformed, so that the installation torque is too large, the fluctuation range of the torque reaches 15 N.M, the front sleeve 3 is not clamped to the pipe 5, and the joint is leaked. Figures 8-9

[0040] The test results of the second group are also undesirable, and the upper and lower deviations x1, y1 of the included angle a of the rear sleeve pressure surface 33 and the upper and lower deviations x2, y2 of the included angle a of the nut driving surface 41 do not satisfy the linear relationship y2 < y1. It is reflected that the action point F between the nut driving surface 41 and the rear sleeve pressure surface 33 during tightening of the joint is deviated downward, as shown in the accompanying drawings, which results in that the front sleeve 2 is fully deformed and clamped to the pipe 5, while the rear sleeve 3 is not clamped to the pipe 5, and the anti-vibration effect of the joint is seriously reduced. Figures 10-11

[0041] The test results of the third group are desirable. The upper and lower deviations x1, y1 of the included angle a of the pressure surface 33 and the upper and lower deviations x2, y2 of the included angle a of the driving surface 41 satisfy the linear relationship y2 < y1. The action point F between the driving surface 41 and the pressure surface 33 during tightening of the joint is at the optimal position, as shown in the accompanying drawings, and the front sleeve 2 and the rear sleeve 3 are both fully deformed and clamped to the pipe 5, which realizes sealing and guarantees the stability of the joint. More importantly, the installation torque of the joint is obviously reduced compared with the first group and the second group, and the fluctuation range of the torque is controlled within 10 N.M. When the included angle a is 150°, the installation torque of the joint is best, and the fluctuation range of the torque is the smallest. Figures 6-7

[0042] Example 2​​​

[0043] The difference between this embodiment and Embodiment 1 lies in the different structures of the connector body 1' and nut 4'. The front ferrule 2 and rear ferrule 3 remain the same as in Embodiment 1. See Appendix for details. Figure 12 In this embodiment, the outer side of the tapered opening 12' of the connector body 1' is provided with a male thread 13', the inner end face of the nut 4' is provided with a mating female thread 43', and the end of the female thread 43' of the nut 4' is provided with a driving surface 41', the included angle of the driving surface 41' is the same as the included angle of the driving surface 41 of the nut 4 in embodiment 1.

[0044] Example 3

[0045] See appendix Figure 13 This embodiment demonstrates another preferred structure for the front ferrule 2′. The rear ferrule 2′ retains all the features of the rear ferrule in Embodiment 1, except that it has an arc-shaped groove 20′ on its inner wall. The arc-shaped groove 20′ is located between the cutting edge 25′ and the end 27′ of the tapered groove 24′. The arc-shaped groove 20′ helps to reduce the deformation of the tapered first front end 21′ of the front ferrule 2′ during the tightening of the connector, which can further reduce the installation torque of the connector.

[0046] Example 4

[0047] See appendix Figures 14-15 The difference between Embodiment 4 and Embodiment 1 is that Embodiment 4 shows a single ferrule connector, i.e., only the connector body 1, ferrule 6, nut 4, and tube 5, wherein the connector body 1 and nut 4 are the same as in Embodiment 1. In this embodiment, the ferrule 6 is annular, with a tapered front end 61 that enters into the tapered opening 12 on the connector body 1 and a radially enlarged rear end 63, with a middle section 62 of basically uniform wall thickness between the tapered front end 61 and the rear end 63. The optimizations for the front ferrule 2 in Embodiment 1 also apply to the ferrule 6, such as providing a nose 66 on the tapered front end 61 and a cutting edge 65 on the inner wall, etc. The above features can also bring the benefits described in Embodiment 1.

[0048] A pressure-bearing surface 64 is provided on the rear end 63 of the ferrule 6. The pressure-bearing surface 64 and the nut driving surface 41 have the same included angle α, and the included angle formed by the driving surface 41 of the nut 4 is... The included angle formed by the pressure-bearing surface 64 of the ferrule 6 is x1, y1 and x2, y2 satisfy the following linear relationship: Where y2 < y1. The included angle α is preferably between 145° and 155°. When the upper and lower deviations of the included angle α satisfy the above linear relationship, the installation torque of the compression fitting can be effectively reduced and the installation torque can be stabilized within the allowable fluctuation range.

[0049] For example, the single ferrule joint with 3 / 8" specification, the upper and lower deviation of the included angle α and the test results of the joint installation torque are as follows:

[0050]

[0051] The test results are consistent with those of Example 1, and the test results of the first group and the second group are undesirable. In the first group, the action point between the nut driving surface 41 and the ferrule pressure bearing surface 64 is deviated upward, resulting in large joint installation torque, large torque fluctuation and unstable installation torque. In the second group, the action point between the nut driving surface 41 and the ferrule pressure bearing surface 64 is deviated downward, and the ferrule is easy to deform excessively, reducing the service life of the joint.

[0052] The test results of the third group are desirable, which is that the action point between the nut driving surface 41 and the ferrule pressure bearing surface 64 is in the best position during joint tightening. At this time, the ferrule 6 reaches a fully deformed state, and the installation torque is not only reduced, but the torque fluctuation is also stable within a very small fluctuation range, especially when the included angle α is 150°.

[0053] Example 5

[0054] The difference between this embodiment and Example 4 is that the joint body 1' and the nut 4' of different structures are presented, and the ferrule 6 is consistent with that in Example 4, which is shown in the attached Figure 16 In this embodiment, the outer side of the tapered opening 12' of the joint body 1' is provided with a male thread 13', and the inner end surface of the nut 4' is provided with a matching female thread 43'. The end of the female thread 43' is provided with a driving surface 41', and the included angle of the driving surface 41' is the same as that of the driving surface 41 of the nut 4 in Example 1.

[0055] Example 6

[0056] This embodiment shows another preferred structure of the ferrule 6', which is shown in the attached Figure 17 The ferrule 6' retains all the features of the ferrule in Example 4, and the difference is that the inner wall is provided with a circular-arc-shaped groove 60', which is located between the cutting edge 65' and the lower end 67' of the pressure bearing surface 64'. The circular-arc-shaped groove 60' helps the deformation of the tapered first front end 61' of the ferrule 6' during joint tightening, which can further reduce the installation torque of the joint.

[0057] The above describes the basic principles and advantages of the present application, and the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same. Although the present application is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments, or make equivalent replacements to some or all of the technical features, by reading the present specification. Any obvious replacements without departing from the concept of the present application are within the protection scope of the present application.

Claims

1. A ferrule connector that reduces and stabilizes installation torque, characterized in that, The connector includes a connector body, a front ferrule, a rear ferrule, and a nut. The connector body has a central hole and a tapered opening at one end, which define a top for receiving the end of a tube. The front ferrule has an annular shape, with a tapered first front end that enters the tapered opening on the connector body and a radially enlarged first rear end with a tapered groove. There is a middle section with a substantially uniform wall thickness between the tapered first front end and the first rear end. The rear ferrule has a second tapered front end that enters the tapered groove on the first rear end of the front ferrule and a radially enlarged second rear end. A pressure-bearing surface is provided on the second rear end. The nut is threaded onto the connector body and has a driving surface. During tightening of the nut with the connector body, the driving surface presses against the pressure-bearing surface. The angle between the pressure-bearing surface and the driving surface is the same. The vertical deviation of the angle between the driving surface and the pressure-bearing surface is x1 and y1, and the vertical deviation of the angle between the driving surface and the pressure-bearing surface is x2 and y2. x1 and y1, and x2 and y2 satisfy the following linear relationship: Where y2 < y1.

2. A ferrule connector with reduced and stable installation torque according to claim 1, characterized in that, The front ferrule is provided with a nose at its tapered first front end. Before the connector is tightened, the nose contacts the tapered opening line of the connector body.

3. A ferrule connector with reduced and stable installation torque according to claim 2, characterized in that, The inner wall of the front sleeve is provided with a cutting edge, which is located below the nose.

4. A ferrule connector with reduced and stable installation torque according to claim 3, characterized in that, The included angle between the pressure-bearing surface and the driving surface is 150°.

5. A ferrule connector with reduced and stable installation torque according to claim 1, characterized in that, The tapered opening of the connector body receives the female thread outward, and one end of the nut is provided with a male thread that mates with it.

6. A ferrule connector with reduced and stabilized installation torque according to claim 5, characterized in that, The driving surface is located at the starting end of the male thread.

7. A ferrule connector with reduced and stable installation torque according to claim 1, characterized in that, The outer side of the tapered opening of the connector body is provided with a male thread, and the inner end face of the nut is provided with a mating female thread.

8. A ferrule connector with reduced and stable installation torque according to claim 7, characterized in that, The driving surface is located at the rear end of the female thread.

9. A ferrule fitting with reduced and stable installation torque according to any one of claims 1-8, characterized in that, The inner wall of the front sleeve is provided with an arc-shaped groove.

10. A ferrule fitting with reduced and stabilized installation torque, characterized in that, The fitting includes a connector body, a ferrule, and a nut. The connector body has a central hole and a tapered opening at one end, which define a top for receiving the end of a tube. The ferrule has an annular shape, with a tapered front end that enters the tapered opening on the connector body and a radially enlarging rear end. There is a central section with a substantially uniform wall thickness between the tapered front end and the rear end. A pressure-bearing surface is provided on the rear end. The nut is threaded onto the connector body and has a driving surface. During tightening of the nut with the connector body, the driving surface presses against the pressure-bearing surface. The angle between the pressure-bearing surface and the driving surface is the same. The vertical deviation of the driving surface angle is x1 and y1, and the vertical deviation of the pressure-bearing surface angle is x2 and y2. x1, y1 and x2, y2 satisfy the following linear relationship: Where y2 < y1.

11. A ferrule connector with reduced and stabilized installation torque according to claim 10, characterized in that, The ferrule has a nose at its tapered front end, which contacts the tapered opening line of the connector body before the connector is tightened.

12. A ferrule connector with reduced and stabilized installation torque according to claim 11, characterized in that, The inner wall of the card holder is provided with a cutting edge, which is located below the nose.

13. A ferrule connector with reduced and stabilized installation torque according to claim 12, characterized in that, The included angle between the pressure-bearing surface and the driving surface is 150°.

14. A ferrule connector with reduced and stabilized installation torque according to claim 10, characterized in that, The tapered opening of the connector body receives the female thread outward, and one end of the nut is provided with a male thread that mates with it.

15. A ferrule connector with reduced and stable installation torque according to claim 14, characterized in that, The driving surface is located at the starting end of the male thread.

16. A ferrule connector with reduced and stable installation torque according to claim 10, characterized in that, The outer side of the tapered opening of the connector body is provided with a male thread, and the inner end face of the nut is provided with a mating female thread.

17. A ferrule connector with reduced and stabilized installation torque according to claim 16, characterized in that, The driving surface is located at the rear end of the female thread.

18. A ferrule fitting with reduced and stabilized installation torque according to any one of claims 10-17, characterized in that, The inner wall of the card sleeve is provided with an arc-shaped groove.

Images