WO2019080896A1

WO2019080896A1 - Metal pipe connecting structure having high-strength anti-corrosion coating

Info

Publication number: WO2019080896A1
Application number: PCT/CN2018/111857
Authority: WO
Inventors: 周庆念; 余张法
Original assignee: 周庆念; 余张法
Priority date: 2017-10-26
Filing date: 2018-10-25
Publication date: 2019-05-02
Also published as: CN109707935A

Abstract

A metal pipe connecting structure having a high-strength anti-corrosion coating, comprising: a snap ring type pipe fitting (1), wherein a sealing groove (2) and a snap ring groove (3) are disposed on an inner circumferential surface of a socket end thereof; a sealing ring (4), disposed in the sealing groove (2); and a metal snap ring (6), which has a notched annular shape, is disposed in the snap ring groove (3) and facilitates deformation, wherein the snap ring type pipe fitting (1) is formed by a metal pipe fitting base body (101) and a high-strength anti-corrosion coating (102) that covers the inner wall of the pipe fitting base body. When a metal pipe (7) is inserted into a socket of the snap ring type pipe fitting (1), the sealing groove (2) and the snap ring groove (3) of the snap ring type pipe fitting (1) are compressed using a crimping tool so that the sealing groove (2) and the snap ring groove (3) deform, thereby achieving a sealed connection between the snap ring type metal pipe fitting (1) and the metal pipe. Since the inner wall of the pipe fitting base body has a high-strength anti-corrosion coating, the connecting pipe fitting in the connection structure may have a thin wall thickness, and the pipe fitting is high strength and has better corrosion resistance. Thus, ordinary metal materials may be used to achieve good crimp deformation properties, thereby improving the sealing performance and reducing the cost of materials.

Description

Metal pipe connection structure with high-strength anti-corrosion coating

Technical field

The invention relates to a metal pipe connection structure, in particular to a metal pipe snap ring connection structure with a high-strength anti-corrosion coating.

Background technique

Fluid delivery pipes are often used in the construction and industrial sectors. Conventional fluid delivery pipes are connected by pipe fittings, which are usually threaded to form various piping systems. As a mature pipe fitting connection method, the installation efficiency of the threaded connection is not high, and there are certain requirements for the working space, and a series of problems such as preventing leakage at the joint are also solved.

For this reason, in recent years, the connection structure of the snap-in metal pipe fittings has been gradually developed. The thin-walled metal tube design uses a special tool to crimp and deform the thin wall, so that the pipe connection is completed instantaneously. As shown in FIG. 1A, in the cross-sectional view of the crimping connection, the crimping tool simultaneously presses the two portions of the socket section M and the sealing groove N, and the sealing groove portion is compressed, forcing the O-ring seal in the groove to be closely attached. The metal pipe (for example, steel pipe) functions to seal and stop the water. The socket section M is pressed by the hexagon, and the metal pipe and the pipe are pressed and deformed, and the rigidity of the metal material itself is utilized to resist the drawing.

The structure is simple in construction, short in operation time, no threaded connection of the joint, no complicated threading operation, no high temperature open flame, no pre-treatment during welding, no oil pollution or welding slag pollution during construction cutting or joining.

As a crimping type pipe fitting, the wall thickness of the snap-in metal pipe fitting must be thin to meet the requirements of sufficient deformation at the time of crimping, and at the same time help to reduce the weight of the product. At the same time, as part of the fluid delivery conduit, it must have sufficient strength. Thickening the wall thickness of course helps to improve the strength, but reduces the formation of sufficient deformation and increases the weight of the product. Excessive pursuit of thin walls results in insufficient strength. Moreover, it is necessary to meet the requirements of fluid corrosion resistance. Stainless steel pipe fittings or copper pipe fittings may be used in piping systems that have certain corrosion resistance requirements (for example, fire sprinkler systems in buildings), but this also leads to an increase in material costs.

The amount of material used to connect the pipe is greater than that of the pipe as the connector, and the use of stainless steel or copper pipes results in a more serious cost increase.

However, pipes using galvanized carbon steel pipes in the snap-fit metal pipe joint structure have great drawbacks. Fig. 1B shows an enlarged view of a portion B of the snap-in metal pipe connecting structure of Fig. 1A. As shown in FIG. 1B, since the socket portion M of the snap-in tubular member 91 is subjected to hexagonal pressing, the galvanized carbon steel pipe 92 and the pipe member are frictionally deformed, resulting in the outer wall of the galvanized carbon steel pipe 92 and the inner wall of the pressed tubular member 91. The galvanized layer is destroyed, and the water flow F in the pipe flows from the gap of the cannula to the hex extrusion deformation portion, and the galvanized layer of the inner wall of the galvanized carbon steel pipe 62 and the pressed pipe member 91 has been destroyed. Carbon steel pipes and fittings are eroded and oxidized under the action of water flow, thereby making the service life of the pipes greatly reduced.

In addition, in the process of inserting the metal tube into the snap-in metal pipe member, the insertion end easily causes damage or displacement of the rubber sealing ring, resulting in a tight seal.

The information disclosed in the Background of the Invention is only intended to provide an understanding of the general background of the invention, and should not be construed as an admission or in any way.

Summary of the invention

The object of the present invention is to provide a metal pipe connecting structure with a high-strength anti-corrosion coating, which can make the connecting pipe itself in the connecting structure have a thin wall thickness, good strength, and thus good crimping deformation performance. At the same time, it has better corrosion resistance.

It is still another object of the present invention to provide a metal pipe joint structure with a high-strength anticorrosive coating which can solve the problem of reduced corrosion resistance of the connected galvanized carbon steel pipe due to damage of the galvanized layer.

It is still another object of the present invention to provide a metal pipe joint structure with a high strength anticorrosive coating which can prevent damage to the seal ring during insertion of the metal pipe member into the joint structure.

The invention provides a metal pipe connection structure with a high-strength anti-corrosion coating, which comprises a snap ring type pipe, wherein a sealing groove and a snap ring groove are arranged on an inner circumferential surface of the socket end; and a sealing ring is disposed on the And a metal snap ring in a ring shape having a notch, thereby being disposed in the snap ring groove and facilitating compression deformation, wherein the snap ring pipe member is made of a metal pipe base body and covers a high strength of at least an inner wall of the pipe base body The anti-corrosion coating is formed. When the metal pipe is inserted into the socket of the snap ring type pipe fitting, the sealing groove and the snap ring groove of the snap ring type pipe are pressed by the crimping tool to deform, thereby being tightened by the metal snap ring. The metal tube is correspondingly deformed, whereby the sealing connection between the metal tube snap ring tubes is achieved by the sealing ring.

In the above metal pipe joint structure with a high-strength anticorrosive coating, preferably, the anticorrosive coating layer is formed of a polyethylene material.

In the above metal pipe joint structure with a high-strength anticorrosive coating, preferably, the metal pipe base is a thin-walled steel pipe.

In the above metal pipe joint structure with a high-strength anticorrosive coating, preferably, the snap ring groove is located axially outward of the seal groove.

In the above metal pipe connection structure with a high-strength anti-corrosion coating, preferably, further comprising a guide ring disposed in the snap ring groove between the seal ring and the metal snap ring, the inner diameter of the guide ring being smaller than the seal ring The inner diameter is larger than the outer diameter of the metal tube. More preferably, the guide ring is made of engineering plastic.

In the above metal pipe joint structure with a high-strength anticorrosive coating, preferably, the inner peripheral surface of the metal snap ring has a toothed structure.

In the above metal pipe joint structure with a high-strength anticorrosive coating, preferably, the inner peripheral surface of the metal snap ring has a tapered surface.

In the above metal pipe joint structure with a high-strength anticorrosive coating, preferably, the width of the cross section of the seal ring is greater than the height. More preferably, the elliptical cross section of the cross section of the sealing ring.

In the above metal pipe joint structure with a high-strength anticorrosive coating, it is preferable to further include an axially outermost impervious ring provided in the socket of the snap ring type pipe member.

In the above metal pipe connection structure with high-strength anti-corrosion coating, since the inner wall of the pipe base has a high-strength anti-corrosion coating, the connecting pipe itself in the connecting structure has a thin wall thickness and good strength, and thus has good performance. Crimp deformation performance, while having better corrosion resistance. Therefore, ordinary metal materials can be used to achieve good crimp deformation properties, thereby improving sealing performance, reducing material cost, and reducing product weight.

In the above metal pipe connection structure with a high-strength anti-corrosion coating, the order of the sealing groove and the snap ring groove is adopted, so that the fluid which penetrates between the snap ring pipe and the inserted metal pipe can reach the galvanizing. The damaged part of the layer is blocked by the sealing ring before it will cause corrosion to the metal pipe, thereby increasing the life of the entire connecting structure.

Further, by the arrangement of the guide ring, the present invention can prevent damage to the seal ring during the insertion of the metal pipe member into the joint structure.

The method and device of the present invention will have other features and advantages, which will be apparent from the drawings and the following detailed description, or the accompanying drawings and The detailed description is set forth with the particular embodiments

DRAWINGS

1A is a schematic view showing a connection structure of a snap-in metal pipe fitting in the prior art.

Fig. 1B shows an enlarged view of a portion B of the snap-in metal pipe connecting structure of Fig. 1A.

2 is a half cross-sectional view showing the construction of a snap ring type pipe joint structure with a high strength anticorrosive coating according to the present invention.

Figure 3 is a half cross-sectional view of the metal pipe connection structure of the present invention with a high-strength anti-corrosion coating, wherein the inside of the snap-in pipe fitting has been installed with a sealing ring, a guide ring, a metal snap ring, an anti-seepage ring, but not yet Assemble with metal tubes.

4 is a cross-sectional view showing a metal pipe connection structure with a high-strength anti-corrosion coating of the present invention, in which a seal ring, a guide ring, a metal snap ring, an anti-seepage ring, and an insertion have been installed inside the snap-in pipe fitting. Metal tube and crimped assembly.

Fig. 5 is an enlarged view showing a portion A of the metal pipe connecting structure of Fig. 4 with a high-strength anticorrosive coating.

Fig. 6 shows a toroidal snap ring of the present invention, wherein the right side view is a cross-sectional view of the left side view.

Figure 7 shows a ring gear type snap ring of the present invention.

It should be understood that the appended drawings are not necessarily to The specific design features of the present invention as disclosed herein, including, for example, the particular dimensions, orientation, positioning, and <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> will be determined in part by the particular application and use environment.

In the figures, the reference numerals are used to refer to the same or equivalent parts of the invention.

Detailed ways

Reference will now be made in detail to the particular embodiments of the invention, While the present invention has been described in connection with the exemplary embodiments, it is understood that this description is not intended to limit the invention to those exemplary embodiments. Rather, the invention is intended to cover various alternatives, modifications, and equivalents, and other embodiments, which are included within the spirit and scope of the invention as defined by the appended claims .

2 is a half cross-sectional view showing the construction of a snap ring type pipe joint structure with a high strength anticorrosive coating according to the present invention. As shown in Fig. 2, the snap ring type pipe member 1 of the metal pipe joint structure with high strength anticorrosive coating of the present invention is formed of a metal pipe base body 101 and a high strength anticorrosive coating layer 102 covering at least the inner wall of the pipe member base. It should be noted that the high-strength anti-corrosion coating 102 may cover only the inner wall of the metal pipe base 101 to provide corrosion resistance to the fluid to be conveyed. Of course, the high strength anticorrosive coating 102 can also be applied to the entire surface of the metal pipe base 101 to provide a comprehensive corrosion resistance.

The high strength anticorrosive coating 102 can be formed from a suitable material, such as high strength polyethylene. The high strength anticorrosive coating 102 can be formed on the metal pipe base 101 by any suitable process.

Due to the presence of the high-strength anti-corrosion coating 102, the metal pipe base 101 can be made of any suitable metal material, such as plain carbon steel, without regard to corrosion resistance, thereby helping to reduce material costs.

The high-strength anti-corrosion coating 102 itself has high strength and density, and is easy to overcome the microscopic defects unique to the metal material, such as blisters, cracks, etc., so that the wall thickness can be made thin. Therefore, it helps to improve the deformation performance of the pipe fitting, thereby improving the quality of the compression seal. And help to reduce the weight of the product.

As shown in Fig. 2, one end of the snap ring type pipe fitting 1 has a socket for inserting a desired metal pipe. The socket of the snap ring type pipe member 1 shown in Fig. 2 is provided with a seal groove 2 and a snap ring groove 3 in this order from the inside to the outside. As a preferred embodiment, this arrangement sequence helps to prevent corrosion of the connected galvanized steel pipe (which will be described later).

The inner diameter of the seal groove 2 and the snap ring groove 3 is larger than the inner diameter of the other portions of the snap ring type pipe member 1 to accommodate the rubber seal ring and the metal snap ring. The snap ring type pipe fitting 1 shown in the drawing is integrally formed.

Figure 3 is a half cross-sectional view showing the metal pipe connection structure of the present invention with a high strength anticorrosive coating. As shown in FIG. 3, the seal ring 4, the guide ring 5, the metal snap ring 6 and the anti-seepage ring 8 have been installed in the seal groove 2 and the snap ring groove 3 of the snap ring type pipe member 1, but have not been assembled with the metal pipe. .

Here, the guide ring 5 is not necessary. The guide ring 5 has a ring shape whose inner diameter is smaller than the inner diameter of the seal ring 4 and larger than the outer diameter of the metal pipe 7 to be inserted.

Figure 4 is a cross-sectional view showing a metal pipe connection structure with a high strength anticorrosive coating of the present invention. Fig. 5 is an enlarged view showing a portion A of the metal pipe connecting structure of Fig. 4 with a high-strength anticorrosive coating. As shown in FIG. 4 and FIG. 5, the sealing ring 4, the guide ring 5, the metal snap ring 6 and the anti-seepage ring 8 have been installed in the sealing groove 2 and the snap ring groove 3 of the snap ring type pipe fitting 1, and the metal is inserted. Tube 7 was crimped and assembled.

Here, the guide ring 5 is not necessary. However, the guide ring 5 has a metal tube 7 that helps guide the insertion to avoid damage or movement of the sealing ring 4, thereby better ensuring the sealing effect. For this purpose, the inner diameter of the guide ring 5 is smaller than the inner diameter of the sealing ring 4 and larger than the outer diameter of the metal tube 7, thereby achieving a guiding effect on the insertion of the metal tube 7.

The guide ring 5 can be made of any suitable plastic material as long as it meets the strength toughness and corrosion resistance requirements, and produces sufficient deformation under pressure without being damaged. It is preferred to use an engineering plastic such as polyethylene or the like.

As a preferred solution, the barrier ring 8 is also not required. The seepage ring 8 is annular, and is disposed at the axially outermost side in the socket of the snap ring type pipe member 1, thereby preventing external moisture from infiltrating into the snap ring type pipe member 1 to cause corrosion. When the snap ring type pipe member 1 is pressed, the seepage prevention ring 8 realizes a seal between the snap ring type pipe member 1 and the metal pipe 7 from the axially outer side.

The anti-seepage ring 8 can be made of any suitable material as long as it can satisfy the strength toughness and corrosion resistance requirements, and produces sufficient deformation under pressure without being damaged. It is preferred to use an engineering plastic such as polyethylene or the like.

Moreover, it should be noted that the arrangement order of the seal ring 4, the guide ring 5, the metal snap ring 6 and the anti-seepage ring 8 shown in the drawing is only a preferred fact. The basic function of the guide ring 5 is to guide the metal tube 7 to be inserted in the center to avoid damage or to move the sealing ring 4. The basic function of the anti-seepage ring 8 is to prevent external moisture from infiltrating into the snap ring tube 1 and causing corrosion, in order to meet the sealing requirements. On the premise, other arrangements are also possible. For example, regardless of the order in which the other related components are arranged, the guide ring 5 is placed in the axial direction of the seal ring 4 in the socket of the snap ring type pipe member 1. For another example, regardless of the order in which the other related components are arranged, the seepage prevention ring 8 is disposed in the axially outermost side in the socket of the snap ring type tubular member 1.

The sealing ring 4 preferably adopts a relatively flat structure, that is, a cross section having a width larger than the height to increase the contact area with the sealed tubular member, thereby improving the sealing effect. For example, a rectangular cross section or an elliptical cross section, or other suitable shape cross section.

The metal snap ring 6 has an annular shape with a notch to reduce the inner diameter when subjected to radial compression. The metal snap ring 6 can take various forms. As an example, Figure 6 shows a toroidal snap ring.

The right side view of Fig. 6 is a cross-sectional view of the left side view. The right side view of Fig. 6 shows that the inner peripheral surface of the metal snap ring 6 has a tapered surface. Of course, this is only an exemplary cross section, and it is also possible to adopt a rectangular cross section as shown in FIGS. 4 and 5. When subjected to radial compression, the engagement of the tapered structure with the deformed metal tube provides axial pressure to further compress the rubber seal, thereby providing a better sealing effect.

Fig. 7 shows a ring-type snap ring 6 having a tooth-like structure distributed in the circumferential direction inside. This toothed structure helps to be inserted into the metal tube when subjected to radial compression to increase the tensile strength. The metal pipe joint structure with high strength anticorrosive coating shown in Fig. 4 is assembled as such. First, the metal pipe 7 is inserted into the socket of the snap ring pipe 1 in which the seal ring 4, the guide ring 5, the metal snap ring 6 and the anti-seepage ring 8 have been mounted as shown in Fig. 3, and then the card is pressed using the pressing tool. The seal groove 2 and the snap ring groove 3 on the ring-shaped pipe member 1 are simultaneously compressed to a predetermined size. At this time, the circumferential compression of the sealing groove 2 forces the inner sealing ring 4 to abut against the metal pipe 8 to form a one-side seal, which prevents fluid leakage in the pipe and satisfies the sealing requirements. At the same time, the snap ring groove 3 is circumferentially compressed, forcing the inner metal snap ring 6 to be tightly inserted into the metal tube 7 to form a compression groove embedded in the metal tube, which satisfies the pipe pull-out performance. When the guide ring 5 is provided, the guide ring 5 is also simultaneously compressed inwardly on the circumference so as to abut against the outer surface of the metal tube 7 and the inner surface of the snap ring tube 1 to form a further seal. When the anti-seepage ring 8 is provided, the anti-seepage ring 8 is also simultaneously compressed inwardly on the circumference so as to be in close contact with the outer surface of the metal pipe 7 and the inner surface of the snap-in tubular member 1 to form a further seal.

The test data shows that the pull-out force of the snap ring connection of the same specification is 2.2 times or more of the pull-out force of the snap-fit connection. The modified pull-up force of the snap-on connection is the same specification. More than 4 times the pull resistance.

As can be seen from Fig. 4, the metal pipe connection structure with the high-strength anti-corrosion coating is only compressed and deformed in the sealing groove 2 and the snap ring groove 3 (in the same area) on the snap ring type pipe member 1, and the other portions are not Will be deformed.

As can be seen from Fig. 5, although the metal clasp 6 is tightly embedded in the metal tube 7, the galvanized layer of the outer wall of the galvanized steel pipe is broken, but the water flowing between the snap ring tube 1 and the inserted metal tube 7 is It is blocked by the sealing ring 4 before reaching the damaged portion of the galvanized layer, so that the metal pipe 7 is not corroded. Also shown in Fig. 5, although the metal clasp 6 is tightly embedded in the metal tube 7, the galvanized layer of the outer wall of the galvanized steel pipe is broken, but the anti-seepage ring 8 is formed at the axially outermost side in the socket of the snap ring type pipe member 1. Sealed, the external moisture does not penetrate into the inside of the snap ring type pipe member 1, and thus the metal pipe 7 is not corroded. In other words, the structure of the present invention allows the connected galvanized steel pipe to not deteriorate in service life due to destruction of the galvanized layer.

The foregoing description of the specific exemplary embodiments of the present invention has The description is not intended to be exhaustive or to limit the scope of the invention. The embodiments were chosen and described in order to explain the particular embodiments of the invention Choices and changes. The scope of the invention is intended to be defined by the appended claims and their equivalents.

Claims

A metal pipe connection structure with a high-strength anti-corrosion coating, characterized in that it comprises:

The snap ring type pipe fitting (1) has a sealing groove (2) and a snap ring groove (3) on the inner circumferential surface of the socket end;

a sealing ring (4) disposed in the sealing groove (2);

a metal snap ring (6) having a ring-shaped annular shape so as to be disposed in the snap ring groove (3) and to facilitate compression deformation.

Wherein the snap ring type pipe member (1) is formed by a metal pipe base body (101) and a high-strength anticorrosive coating (102) covering at least an inner wall of the pipe base body,

When the metal pipe (7) is inserted into the socket of the snap ring type pipe fitting, the sealing groove (2) of the snap ring type pipe member (1) and the snap ring groove (3) are pressed by the crimping tool to deform, thereby passing the metal The tightening deformation of the snap ring causes the metal tube (7) to be deformed accordingly, whereby the sealing connection between the metal tube (7) snap-on tube (1) is achieved by the sealing ring (4).
A metal pipe joint structure with a high-strength anticorrosive coating according to claim 1, wherein the anticorrosive coating (102) is formed of a polyethylene material.
A metal pipe joint structure with a high-strength anticorrosive coating according to claim 1, wherein the metal pipe base (101) is a thin-walled steel pipe.
A metal pipe joint structure with a high-strength anticorrosive coating according to claim 1, wherein the snap ring groove (3) is located axially outward of the seal groove (2).
The metal pipe connection structure with high-strength anti-corrosion coating according to claim 1, further comprising a ring (3) disposed in the snap ring groove (4) and a metal snap ring (6) The guiding ring (5), the inner diameter of the guiding ring is smaller than the inner diameter of the sealing ring and larger than the outer diameter of the metal pipe (7).
A metal pipe joint structure with a high-strength anticorrosive coating according to claim 5, wherein the guide ring is made of an engineering plastic.
The metal pipe joint structure with a high-strength anticorrosive coating according to claim 1, wherein an inner peripheral surface of the metal snap ring has a toothed structure.
The metal pipe joint structure with a high-strength anticorrosive coating according to claim 1, wherein an inner circumferential surface of the metal snap ring has a tapered surface.
A metal pipe connection structure with a high-strength anti-corrosion coating according to claim 1, characterized in that the width of the cross section of the sealing ring (4) is greater than the height.
The metal pipe connection structure with high-strength anti-corrosion coating according to claim 8, further comprising an axially outermost anti-seepage ring disposed in the socket of the metal snap-on pipe member (1) ).