CN116928481A - Pipe fitting joint for pre-tightening pipe fitting and application - Google Patents

Abstract

The invention provides a pipe fitting joint of a pre-tightening type hooping pipe fitting and application thereof, and relates to the technical field of plastic pipelines. Through set up the opening on the split ring, when connecting plastic pipe, can directly observe the condition of inserting of plastic pipe from the opening part, guarantee that plastic pipe inserts in place to guaranteed plastic pipe attach fitting's leakproofness, and split ring's setting makes and connects closely between plastic pipe and the inner tube, avoided the medium of carrying in the pipeline to reveal the risk. The structure does not need special installation tools, the installation operation is simple, quick and efficient, the installation cost is effectively reduced, the pipe fitting joint can be repeatedly disassembled and assembled for use, and the structure is more environment-friendly.

Description

Pipe fitting joint for pre-tightening pipe fitting and application

Technical Field

The invention relates to the technical field of plastic pipelines, in particular to a pipe fitting joint for pre-tightening pipe fittings and application.

Background

The pipeline has a fixed length in the production process, but in the use process of the pipeline, two or more pipelines are usually required to be connected to convey the medium, so that the tightness of the connection part is ensured in the pipeline connection process, and the pipeline joint has great significance on safe and complete conveying of the medium and is one of factors for evaluating the quality of the pipeline joint.

The existing pipe joint usually adopts an external sealing direct-insertion pipe fitting, a clamp type, a flaring sliding type, a nut clamping sleeve type and the like. The external sealing direct-insertion type pipe fitting cannot see the insertion pipe condition in the pipe fitting when being installed, and is easy to deviate from or leak water in use due to the fact that the insertion pipe is not in place; the clamp-press type joint and the flaring are smooth and tight, special hydraulic engineering is needed, special tools are needed for installation, the specificity is high, the operation is complex, the leakage of the joint is easy to occur due to improper operation, and the time and the labor are wasted, and the financial resources are damaged; after the flaring sliding-tight type and nut clamping sleeve type joint is used for a period of time, the nuts and the sliding-tight sleeves are easy to loosen, and if the nuts and the sliding-tight sleeves are not timely re-tightened or maintained, the pipe fitting joint is easy to leak. Therefore, how to improve the installation efficiency of the pipe joint, reduce the operation difficulty and the installation cost, and improve the safety performance of the pipe joint is one of the problems to be solved in the art.

In view of this, the present invention has been made.

Disclosure of Invention

The invention aims to provide a pipe fitting joint of a pre-tightening type hooping pipe fitting and application thereof, which can improve the installation efficiency of a pipe joint, reduce the operation difficulty and the installation cost and improve the safety performance of the pipe joint.

Embodiments of the present invention are implemented as follows:

in a first aspect, the invention provides a pipe fitting joint for pre-tightening pipe fittings, comprising an inner pipe and a split ring arranged on the surface of the inner pipe.

The outer surface of the inner tube is provided with a boss, and at least one side of the boss is a tube inserting section of the inner tube. In an alternative embodiment, both sides of the boss of the inner tube may be cannula segments, or only one side may be cannula segments, which may be specifically set according to the requirement of the pipe connection. In other embodiments, when the inner tube is of a tee joint, a four-way structure, or the like, the number of bosses may be plural, for example, when the inner tube is of a tee joint, and three ends of the tee joint all need to be connected with a plastic pipeline, three bosses are disposed on the inner tube of the tee joint structure, and one side from each boss to the corresponding end is a cannula section.

Further, the cannula section is provided with a first limiting piece, the first limiting piece is arranged at intervals with the boss, and a first clamping groove is formed between the first limiting piece and the boss; the split ring is provided with the second locating part, and the second locating part sets up in the terminal surface of split ring one end, and the second locating part holds in first draw-in groove, with the spacing cooperation of first locating part for fix the split ring on the inner tube surface, and the inner wall of split ring sets up with the intubate section interval. The split ring is fixed on the surface of the inner pipe through the cooperation among the first limiting piece, the second limiting piece and the first clamping groove, so that the abrasion of the intubation section structure of the inner pipe can be prevented when the pipe fitting joint is not used; when the pipe fitting joint is used, the plastic pipeline can be better fixed between the split ring and the inner pipe, and the effect of stable installation of the pipeline joint is achieved.

It will be appreciated that the tube fitting is a tube segment of an inner tube, a plastic tube and a split ring in that order from inside to outside during use. The outer diameter of the cannula section should therefore be slightly smaller than the inner diameter of the plastic tubing.

The axial wall of split ring is provided with the opening with split ring axial parallel, sets up the intubate condition that the opening can observe plastic conduit, observes whether plastic conduit intubates in place, avoids because the intubate condition of plastic conduit can't be seen, leads to plastic conduit intubate not in place, and the medium of carrying in the pipeline that appears is missed etc. phenomenon.

The outer wall surfaces of both sides of the opening part are respectively provided with a first fixing part and a second fixing part, and the first fixing part and the second fixing part are respectively provided with a first coaxial mounting hole for mounting bolts to control the opening and closing of the opening part. The split ring is in a natural state, and the split ring can be fastened by the action of the bolts and the nuts to enable the split ring to be in a closed state.

In an alternative embodiment, the bolt and nut cooperate to control the opening and closing of the opening. After the plastic pipe is inserted into place, the nut may be a locknut in order to better ensure that the opening of the split ring is stably closed. Preferably, the bolt is connected to the locknut by a flat washer and a spring washer.

In an alternative embodiment, the spring washer is made of high-strength spring steel, is a spiral split ring washer, and is always provided with a pretightening force after being installed to enable the split ring to be in a tightening state, so that the inverted tooth on the inner wall surface of the split ring is always in a pipe pressing state, and the bolt assembly is prevented from loosening or affecting the sealing effect.

In an alternative embodiment, a second mounting hole penetrating the first fixing portion and parallel to the first mounting hole is further provided on the first fixing portion. Can be used for placing the club structure in the second mounting hole, for example structures such as iron rod, screw, after the club structure passed the second mounting hole, because do not set up corresponding hole on the second fixed part, therefore the club can support the second fixed part to realize the opening increase of split ring, with the fixed demand of installation of adaptation split ring and inner tube, and the fixed demand of installation of plastics pipeline and split ring.

In an alternative embodiment, the inner tube is further provided with a plurality of protruding portions, the protruding portions are arranged at one side, far away from the boss, of the first limiting piece at intervals, the protruding portions encircle the outer wall surface of the inner tube, and the protruding portions are circumferentially distributed on the outer wall surface of the inner tube. The arrangement of the protruding part can enable the plastic pipeline to be in contact with the protruding part when the plastic pipeline is inserted into the inner pipe, so that the friction force of the plastic pipeline separated from the inner pipe is increased, and the plastic pipeline and the inner pipe are prevented from relative rotation to influence sealing. In addition, after the split ring contacts with the inner pipe, the plastic pipeline can be pressed to be embedded on the protruding part due to the closing force of the split ring, so that the friction force between the plastic pipeline and the protruding part is increased again, and the plastic pipeline and the inner pipe are prevented from relative rotation to influence sealing.

Preferably, each of the projections has a triangular prism shape in order to better inlay the plastic pipe on the projection. In other alternative embodiments, the raised portion may have a quadrangular prism, a pentagonal prism, or the like.

Preferably, an end of each boss, which is remote from the first limiting member, is provided with an inclined surface. The inclined surface is used for facilitating the insertion of the plastic pipeline, and the inclined surface is used as an introduction surface, so that the difficulty in inserting the plastic pipeline into the inner pipe is reduced.

In an alternative embodiment, in order to better avoid leakage of the medium conveyed in the pipeline, a plurality of sealing grooves are arranged on the inner pipe, and sealing elements are arranged in each sealing groove.

Preferably, the seal may be a sealing ring.

Preferably, the plurality of seal grooves are all arranged on one side of the protruding portion away from the first limiting piece.

In an alternative embodiment, the sealing grooves are two, namely a first sealing groove and a second sealing groove, a first groove is further arranged between the protruding portion and the first sealing groove, a second groove is further arranged between the first sealing groove and the second sealing groove, and a third groove is further arranged between the second sealing groove and the end face of the tube inserting section. The two sealing grooves are arranged to provide double guarantee for sealing the pipeline, then three grooves are alternately formed near the two sealing grooves, the protrusions forming the grooves can also serve as surfaces in contact with the plastic pipeline, and the friction force between the protrusions and the plastic pipeline is improved. When the opening ring is tightened, the plastic pipeline can be clamped into the three grooves, and the plastic pipeline is prevented from being separated from the inner pipe while the plastic pipeline is further sealed. The above is only to better ensure the medium transmission stability and the tightness after the plastic pipeline is connected, and in other embodiments, the number of the grooves on the inner pipe can be set according to specific needs.

In an alternative embodiment, at least one of the first, second and third grooves is provided with a bevel inclined in the direction of the end face of the cannula section.

Preferably, in order to facilitate the insertion of the pipe and to facilitate the increase of friction between the inner pipe and the plastic pipe, both the second groove and the third groove are provided with inclined surfaces inclined in the direction of the end face of the pipe insertion section.

In an alternative embodiment, to facilitate insertion of the pipe, the end face of the pipe section is provided with a guiding ramp which is inclined along the end face opening of the pipe section. Wherein the end face opening of the tube insertion section refers to the mouth of the end face of the inner tube.

In alternative embodiments, the material of the inner tube may be metal or a stronger engineering plastic.

In an alternative embodiment, the inner wall surface of the split ring is provided with three raised inverted teeth, each inverted tooth being in one-to-one correspondence with a groove of the cannula section of the inner tube. In other embodiments, when the number of grooves of the inner tube is different, the number of teeth of the inner wall surface of the split ring may also be different.

The inverted tooth extends along the axial direction of the split ring, so that the inner diameter formed by the inverted tooth is smaller than the inner diameter of the flat part of the inner wall surface of the split ring.

Preferably, the inverted tooth is provided with an inclined surface inclined in a direction away from the second limiting piece, so that the inverted tooth is convenient to contact and fix with the plastic pipeline.

Preferably, in order to avoid that the opening cannot be closed when the opening ring is closed under the action of external force, or the outer wall surface of the plastic pipeline is extruded after the opening ring is closed to damage the pipeline structure, the opening of the opening ring is further provided with a chamfer.

In an alternative embodiment, in order to fix the split ring and the inner tube more firmly, the second limiting member is a limiting stop, and the limiting stop extends towards the axis of the split ring, so that the split ring is accommodated in the first clamping groove.

Preferably, in order to better fix the split ring, the limit stops are two, and are correspondingly arranged at two ends of the split ring at intervals.

Preferably, the width of each limit stop in the radial direction is smaller than the diameter of the tip of the inverted tooth.

Preferably, the distance between the two limit stops is smaller than the diameter of the tip of the inverted tooth.

In an alternative embodiment, an inclined surface is arranged at one end of the split ring away from the second limiting piece, so that the split ring is convenient to install and detach.

In an alternative embodiment, in order to prevent the bolts from rotating during the installation of the split ring and affecting the installation, a bolt countersink is further provided on the outer side of the first installation hole. In an alternative embodiment, the bolt countersink may be disposed on the first fixing portion or the second fixing portion, and when the bolt countersink is disposed on the first fixing portion, the outer side of the first mounting hole means a side of the first fixing portion away from the second fixing portion. When the bolt sinking groove is arranged on the second fixing part, the outer side of the first mounting hole refers to one side of the second fixing part away from the first fixing part.

In alternative embodiments, the split ring material may be metal or a stronger engineering plastic.

In a second aspect, the present invention provides the use of a pipe fitting joint of a pretensioned gripping pipe according to any of the preceding embodiments in the field of plastic pipe connections.

The embodiment of the invention has the beneficial effects that:

the invention provides a pipe fitting joint of a pre-tightening type hooping pipe fitting and application, wherein an opening is formed in an opening ring, when a plastic pipe is connected, the insertion condition of the plastic pipe can be directly observed from the opening, and the plastic pipe is ensured to be inserted in place, so that the tightness of the plastic pipe connecting joint is ensured, the plastic pipe is tightly connected with an inner pipe through the arrangement of the opening ring, and the risk of leakage of a medium conveyed in the pipe is avoided. The structure does not need special installation tools, the installation operation is simple, quick and efficient, the installation cost is effectively reduced, the pipe fitting joint can be repeatedly disassembled and assembled for use, and the structure is more environment-friendly.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of an assembled pipe fitting joint of a pretensioned ferrule-based pipe fitting according to an embodiment of the present invention;

FIG. 2 is an exploded view of a pipe fitting joint of a pretensioned grip pipe fitting according to an embodiment of the present invention;

FIG. 3 is a schematic structural view of an inner tube according to an embodiment of the present invention;

FIG. 4 is a cross-sectional view of an inner tube according to an embodiment of the present invention;

FIG. 5 is a schematic view of a split ring according to an embodiment of the present invention from different viewing angles;

fig. 6 is a schematic structural diagram of an assembled pipe fitting joint of a pretensioned pipe fitting and a plastic pipe according to an embodiment of the present invention;

fig. 7 is a sectional view of a pipe fitting joint of a pretensioned grip pipe fitting according to an embodiment of the present invention assembled with a plastic pipe.

The icon is 100-a pipe fitting joint of the pre-tightening type hooping pipe fitting; 1101-boss; 110-an inner tube; 111-a first limiting piece; 112-a first card slot; 113-a boss; 114-a first seal groove; 115-a second seal groove; 116-a first groove; 117-a second groove; 118-third groove; 119-guiding inclined plane; 120-split ring; 121-limit stops; 122-opening; 123-a first fixing portion; 124-a second securing portion; 125-a first mounting hole; 126-a second mounting hole; 127-pouring teeth; 128-chamfering; 129-bolt countersink; 130-a sealing ring; 141-a bolt; 142-plain washers; 143-a spring washer; 144-locknut; 145-screws; 200-plastic pipeline.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the present invention, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or are directions or positional relationships conventionally put in use of the inventive product, are merely for convenience of describing the present invention and simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal," "vertical," and the like do not denote a requirement that the component be absolutely horizontal or overhang, but rather may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

First embodiment

Referring to fig. 1, the present embodiment provides a pipe fitting joint 100 for tightening a pipe fitting in a pre-tightening manner, which includes an inner pipe 110 and a split ring 120 disposed on a surface of the inner pipe 110.

Referring to fig. 2 and 3, a boss 1101 is disposed on an outer surface of the inner tube 110, and at least one side of the boss 1101 is a tube insertion section of the inner tube 110. In this embodiment, the boss 1101 of the inner tube 110 is cannulated on one side and a conventional threaded configuration on the other side. In other embodiments, when the inner tube 110 has a multi-way structure such as a tee, a four-way structure, etc., the number of bosses 1101 may be plural, for example, when the inner tube 110 has a tee structure and three ends of the tee are all required to be connected to the plastic pipe 200, three bosses 1101 are disposed on the inner tube 110 of the tee structure, and a side from each boss 1101 to the corresponding end is a cannula section.

Further, referring to fig. 4, the insertion tube section is provided with a first limiting member 111, and the first limiting member 111 is spaced from the boss 1101, and a first clamping groove 112 is formed between the first limiting member 111 and the boss 1101; the split ring 120 is provided with a second limiting member, the second limiting member is disposed on an end surface of one end of the split ring 120, the second limiting member is accommodated in the first clamping groove 112 and is in limiting fit with the first limiting member 111, and is used for fixing the split ring 120 on the surface of the inner tube 110, and the inner wall surface of the split ring 120 is disposed at intervals with the cannula section. The split ring 120 is fixed on the surface of the inner pipe 110 through the cooperation between the first limiting piece 111, the second limiting piece and the first clamping groove 112, so that the abrasion of the intubation section structure of the inner pipe 110 can be prevented when the pipe fitting joint is not used; when the pipe fitting joint is used, the plastic pipeline 200 can be better fixed between the split ring 120 and the inner pipe 110, and the effect of stable installation of the pipeline joint is achieved.

It will be appreciated that the fitting is, in use, a spigot section of the inner tube 110, a plastic conduit 200 and a split ring 120, in that order from the inside to the outside. Accordingly, the outside diameter of the cannula section should be slightly smaller than the inside diameter of the plastic tubing 200.

Referring to fig. 5, an opening 122 axially parallel to the opening ring 120 is provided on an axial wall surface of the opening ring 120, and the opening 122 is provided to observe the insertion condition of the plastic pipe 200, and to observe whether the plastic pipe 200 is inserted in place, so as to avoid the phenomena of missed medium conveying in the pipe, etc. caused by the fact that the insertion condition of the plastic pipe 200 cannot be observed, which results in the insertion of the plastic pipe 200.

The outer wall surfaces of both sides of the opening 122 are respectively provided with a first fixing part 123 and a second fixing part 124, and the first fixing part 123 and the second fixing part 124 are respectively provided with a first coaxial mounting hole 125 for controlling the opening and closing of the opening 122 by a mounting bolt 141. In the natural state of the split ring 120, the split 122 is opened, and the split ring 120 can be fastened by the bolts 141 and nuts, so that the split 122 is closed.

Referring to fig. 2, in the present embodiment, the bolt 141 and the nut jointly control the opening and closing of the opening 122. After the plastic pipe 200 is inserted in place, in order to better ensure that the opening 122 of the split ring 120 can be stably closed, the bolt 141 is connected to the locknut 144 by means of a flat washer and a spring washer 143.

Specifically, the spring washer 143 is made of high-strength spring steel, and is a washer of the spiral split ring 120, and after installation, a pretightening force is always applied to make the split ring 120 in a tightened state, so that the inverted tooth 127 on the inner wall surface of the split ring 120 is always in a state of pressing a pipe, and the loosening of the bolt 141 assembly or the influence on the sealing effect is prevented.

Referring to fig. 5, in the present embodiment, a second mounting hole 126 penetrating the first fixing portion 123 and parallel to the first mounting hole 125 is further provided on the first fixing portion 123. In the present embodiment, the second mounting hole 126 may be used for placing a club structure, for example, a screw 145, and after the screw 145 passes through the second mounting hole 126, since no corresponding hole is provided on the second fixing portion 124, the screw 145 will abut against the second fixing portion 124, so as to enlarge the opening 122 of the split ring 120, so as to adapt to the installation and fixation requirements of the split ring 120 and the inner tube 110, and the installation and fixation requirements of the plastic pipe 200 and the split ring 120.

Referring to fig. 3 and 4, in the present embodiment, a plurality of protruding portions 113 are further disposed on the inner tube 110, the protruding portions 113 are disposed at a side of the first limiting member 111 away from the boss 1101 at intervals, and the protruding portions 113 encircle the outer wall surface of the inner tube 110 and are circumferentially distributed on the outer wall surface of the inner tube 110. The protruding part 113 can make the plastic pipe 200 contact with the protruding part 113 when the plastic pipe 200 is inserted into the inner pipe 110, so that the friction force of the plastic pipe 200 separating from the inner pipe 110 is increased, and the plastic pipe 200 and the inner pipe 110 are prevented from relative rotation to influence the sealing. In addition, after the split ring 120 contacts with the inner tube 110, due to the closing force of the split ring 120, the plastic tube 200 is pressed to be embedded on the boss 113, so that the friction force between the plastic tube 200 and the boss 113 is increased again, and the plastic tube 200 and the inner tube 110 are prevented from relative rotation to affect sealing.

Further, in order to make the plastic pipe 200 better fitted on the protrusions 113, each protrusion 113 has a triangular prism shape. An end of each boss 113 remote from the first stopper 111 is provided with an inclined surface. The inclined surface is provided to facilitate insertion of the plastic pipe 200, and serves as an introduction surface to reduce difficulty in inserting the plastic pipe 200 into the inner pipe 110.

In this embodiment, in order to better avoid leakage of the medium conveyed in the pipeline, two sealing grooves are provided on the inner pipe 110, and a sealing ring 130 is provided in each sealing groove. Both seal grooves are disposed on one side of the boss 113 away from the first limiting member 111.

Further, the two sealing grooves are a first sealing groove 114 and a second sealing groove 115 respectively, a first groove 116 is further arranged between the protruding portion 113 and the first sealing groove 114, a second groove 117 is further arranged between the first sealing groove 114 and the second sealing groove 115, and a third groove 118 is further arranged between the second sealing groove 115 and the end face of the insertion tube section. The provision of two seal grooves can provide dual protection for sealing the pipe, and then three grooves are alternately formed near the two seal grooves, and the protrusions forming the grooves can also serve as surfaces in contact with the plastic pipe 200, thereby improving friction with the plastic pipe 200. When the split ring 120 is tightened, the plastic tubing 200 will snap into the three grooves, further sealing and avoiding separation of the plastic tubing 200 from the inner tube 110.

In order to facilitate the insertion of the tube and to increase the friction between the inner tube 110 and the plastic tube 200, both the second 117 and the third 118 groove are provided with inclined surfaces inclined in the direction of the end face of the cannula section.

In this embodiment, to facilitate insertion of the pipe, the end face of the pipe section is provided with a guide slope 119, and the guide slope 119 is inclined along an end face opening 122 of the pipe section. The end opening 122 of the cannula section refers to the mouth of the end surface of the inner tube 110.

Referring to fig. 5, in the present embodiment, three protruding inverted teeth 127 are provided on the inner wall surface of the split ring 120, and each inverted tooth 127 corresponds to a groove of the insertion tube segment of the inner tube 110 one by one. Here, since the inverted tooth 127 extends in the axial direction of the split ring 120, the inverted tooth 127 has an inner diameter smaller than that of the flat portion of the inner wall surface of the split ring 120. The inverted tooth 127 has an inclined surface inclined in a direction away from the second stopper, so as to be in contact with and fixed to the plastic pipe 200.

Further, in order to avoid that the opening 122 cannot be closed when the split ring 120 is closed under the action of external force, or the split ring 120 is closed to squeeze the outer wall surface of the plastic pipeline 200, the pipeline structure is damaged, and a chamfer 128 is further provided at the opening 122 of the split ring 120.

In this embodiment, in order to fix the split ring 120 and the inner tube 110 more firmly, the second limiting member is a limiting stop 121, and the limiting stop 121 extends toward the axis of the split ring 120, so as to accommodate the split ring 120 in the first clamping groove 112.

Specifically, in order to better fix the split ring 120, the limit stops 121 are provided at two ends of the split ring 120 at corresponding intervals. The width of each limit stop 121 in the radial direction is smaller than the diameter of the tip of the inverted tooth 127. The distance between the two limit stops 121 is smaller than the diameter of the tip of the inverted tooth 127.

In this embodiment, an inclined surface is disposed at an end of the split ring 120 away from the second limiting member, so as to facilitate the installation and the removal of the split ring 120.

In this embodiment, in order to facilitate installation and prevent the bolts 141 from rotating during the installation of the split ring 120, affecting the installation, a bolt countersink 129 is further provided on the outer side of the first installation hole 125. In an alternative embodiment, the bolt recess 129 may be provided on the first fixing portion 123 or the second fixing portion 124, and when the bolt recess 129 is provided on the first fixing portion 123, the outside of the first mounting hole 125 refers to a side of the first fixing portion 123 away from the second fixing portion 124. When the bolt countersink 129 is provided on the second fixing portion 124, the outside of the first mounting hole 125 refers to a side of the second fixing portion 124 away from the first fixing portion 123.

In this embodiment, the materials of the inner tube 110 and the split ring 120 are both metals.

The pipe fitting joint 100 of the pre-tightening pipe fitting provided in this embodiment is installed as follows:

referring to fig. 1 and 2, firstly, sealing rings 130 are installed in two sealing grooves of the inner tube 110, then screws 145 are placed in the second installation holes 126 of the split ring 120, the width of the opening 122 of the split ring 120 is increased by the abutting action of the screws 145, and the distance between two limit stops 121 at one end of the split ring 120 is increased, so that the limit stops 121 are clamped into the first clamping grooves 112 by the first limit parts 111 of the inner tube 110, and the screws 145 are loosened to make the split ring 120 in a natural state.

A bolt 141 is put into the first mounting hole 125 of the split ring 120, the head of the bolt 141 is positioned at the bolt sinking groove 129, the other end of the bolt 141 passes through the first mounting hole 125, then the bolt 141 is fixed through a flat washer 142, a spring washer 143 and a locknut 144, and the opening 122 of the split ring 120 is tightened, so that the installation of the pipe fitting joint 100 of the pre-tightening pipe fitting is completed.

Referring to fig. 6 and 7, when the plastic pipe 200 is required to be inserted, in a state that the pipe fitting joint 100 of the pretensioned pipe fitting is assembled, the bolts 141 and nuts are loosened to make the split ring 120 in a natural state, then the second installation hole 126 is abutted by the bolts 145 to increase the distance between the two limit stops 121, the plastic pipe 200 is inserted from the guide slope 119 of the end face opening 122 of the inner pipe 110, the insertion position of the plastic pipe 200 is observed through the opening 122 of the split ring 120, when the plastic pipe 200 is completely inserted and contacts the boss 1101, the plastic pipe 200 is completely inserted, at this time, the bolts 145 are loosened to automatically rebound the split ring 120, then the bolts 141 are placed in the first installation hole 125, and the openings 122 of the split ring 120 are tightened by the fixation of the bolts 141, the flat washers 142, the spring washers 143 and the locknuts 144 to complete the assembly of the plastic pipe 200.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. The pipe fitting joint of the pre-tightening type hooping pipe fitting is characterized by comprising an inner pipe and an opening ring arranged on the surface of the inner pipe;

the outer surface of the inner tube is provided with a boss, at least one side of the boss is an insertion tube section of the inner tube, the insertion tube section is provided with a first limiting piece, the first limiting piece is arranged at intervals with the boss, and a first clamping groove is formed between the first limiting piece and the boss; the split ring is provided with a second limiting piece, the second limiting piece is arranged on the end face of one end of the split ring, the second limiting piece is accommodated in the first clamping groove and is in limiting fit with the first limiting piece, and the second limiting piece is used for fixing the split ring on the surface of the inner pipe;

the axial wall surface of the split ring is provided with an opening parallel to the axial direction of the split ring, the outer wall surfaces of two sides of the opening are respectively provided with a first fixing part and a second fixing part, and the first fixing parts and the second fixing parts are respectively provided with first mounting holes with the same axle center for mounting bolts to control the opening and closing of the opening.

2. A pipe fitting joint according to claim 1, wherein the first fixing portion is further provided with a second mounting hole penetrating the first fixing portion and parallel to the first mounting hole.

3. The pipe fitting joint according to claim 1, wherein a plurality of protruding portions are further provided on the inner pipe, the plurality of protruding portions are disposed at intervals on one side of the first limiting member away from the boss, and the plurality of protruding portions are wound around an outer wall surface of the inner pipe;

preferably, each of the convex parts has a triangular prism shape;

preferably, an end of each protruding portion, which is far away from the first limiting piece, is provided with an inclined surface.

4. A pipe fitting joint according to claim 3, wherein the inner pipe is provided with a plurality of sealing grooves, each sealing groove being provided with a seal therein;

preferably, the sealing grooves are all arranged on one side, away from the first limiting piece, of the protruding portion.

5. A pipe fitting joint according to claim 4, wherein the two sealing grooves are a first sealing groove and a second sealing groove respectively, a first groove is further arranged between the protruding portion and the first sealing groove, a second groove is further arranged between the first sealing groove and the second sealing groove, and a third groove is further arranged between the second sealing groove and the end face of the pipe insertion section.

6. A pipe fitting according to claim 5, wherein at least one of the first, second and third grooves is provided with a bevel inclined in the direction of the end face of the pipe insertion section.

7. A fitting according to claim 1, wherein the end face of the tube section is provided with a guiding ramp which is inclined along the end face opening of the tube section.

8. A fitting according to claim 4 or 5, wherein the inner wall surface of the split ring is provided with three raised inverted teeth, each of which is in one-to-one correspondence with a groove of the spigot section of the inner tube;

preferably, the inverted tooth has a slope inclined in a direction away from the second stopper;

preferably, a chamfer is further arranged at the opening of the split ring.

9. The fitting according to claim 8, wherein said second stop is a limit stop extending toward the axis of said split ring;

preferably, the number of the limit stops is two, and the limit stops are correspondingly arranged at two ends of the split ring at intervals;

preferably, a width of each of the limit stops in a radial direction is smaller than a diameter of a tooth tip of the inverted tooth;

preferably, the distance between the two limit stops is smaller than the diameter of the tooth tip of the inverted tooth.

10. Use of a pipe fitting joint of a pretensioned gripping pipe according to any one of claims 1 to 9 in the field of plastic pipe connections.