CN104024714A - Couplings and pipe fittings for connecting pipe fittings to pipes of polymeric material - Google Patents

Abstract

The present invention relates to pipe fittings. The joint for connecting the pipe fitting and the polymeric material pipe comprises a branch pipe arranged on a rigid body of the straight-through pipe, a thin-wall sleeve pipe with a convex edge and an outward end part, wherein the thin-wall sleeve pipe is arranged inside a connecting end of the polymeric material pipe, the convex edge is propped against the end face of one end of the pipe, and the joint further comprises a connecting pipe nut, a compression sleeve pipe and a sealing ring. The branch pipe (2) is provided with an external threaded zone (10), an internal bore (11) with a cylindrical surface, an internal ladder (12) perpendicular to the axis, and an internal conical surface (13) facing the free end (14) of the branch pipe and openable from the side of the free end of the branch pipe. The adapter nut (7) is provided with an inner radial annular bulge (15), the bulge is provided with a conical surface (16), and the conical surface is arranged in the cavity of the adapter nut and along the inner side of the annular bulge. The compression sleeve (8) is made of a metal alloy, the surface of the compression sleeve is free of gaps and is mounted in a snap fit with the outer surface of the tube, compression is carried out between the inner conical surface and the conical surface along the sides opposite the axis, and the edge is deformed into the axis of the compression sleeve along the sides opposite the axis, letting the edge penetrate into the material of the end of the tube (5). The technical effect achieved is that reliable sealing is guaranteed, and the bearing capacity and reliability of connection are improved.

Description

Couplings and pipe fittings for connecting pipe fittings to pipes of polymeric material

technical field

The present invention relates to the field of construction, in particular to a joint for connecting pipe fittings and polymeric material pipes and special pipe fittings for joints. The special pipe fittings for joints are a kind of pipe connectors, which can have different forms, including distributors, valves , filters, pressure reducers and their combinations.

Background technique

A joint is known for connecting pipe fittings to pipes of polymeric material, comprising a rigid body with a bore with an inner conical portion, the apex of which points into the body; and a nipple, said nipple One side has a tapered surface that engages the inner tapered portion of the bore of the fitting body, and the other side has a branch with claw-like projections on the outside of the branch, over which a polymeric sleeve fits; also includes a union nut and Compression sleeve. (US2008/0191475A1, International Classification Number F16L25/00, 2008).

The union nut is provided with an inner radial projection having a surface facing the shaft that transitions from conical to cylindrical. The takeover nut is screwed on the joint body through the external thread area, and the pipe sleeved on the above-mentioned takeover branch pipe passes through the hole on the takeover nut. The takeover nut uses its own internal radial protrusion to make the takeover pipe with a tapered surface face the hole of the joint body. The inner cone is partially curled. The apex of the inner radially convex shaft-facing conical surface of the union nut is oriented in the direction of the fitting body, while its elongated cylindrical surface part extends into the fitting body.

The compression sleeve is configured as a cylinder with external conical slopes on both sides. Compression sleeves are made of a metal alloy and there are no gaps on the surface of the compression sleeve. The nozzle on this side of the branch has an undercut with a conical surface facing the branch. The end of the polymeric tube over the branch and the edge of the compression sleeve over the polymeric tube in this region passes through the undercut. The compression sleeve abuts against the radially protruding conical surface inside the union nut from the other side.

When the union nut is tightened, the compression sleeve deforms and takes as far as possible the shape of the radially raised outer surface inside the union nut, which squeezes the compression sleeve along both sides of the end face opposite the shaft, causing the compression sleeve to Penetrates deep into the polymeric pipe material to ensure a more reliable connection between the pipe fitting and the polymeric pipe. Between the connecting pipe and the body, and between the polymer material pipe and the branch pipe of the connecting pipe are sealed with additionally installed elastic sealing rings.

Such known joints increase the hydraulic losses of the pipeline due to the narrowing of the flow section of the pipeline on the branch part of the connection. Claw-like protrusions on the outer surface of the nozzle branch can cut through the inner support layer of the polymer tube, which reduces connection reliability and reduces service life.

There is known a joint for connecting pipe fittings and metal pipes, which includes branch pipes arranged on the hard body of the pipe fittings, and a thin-walled sleeve with a knurled end outward, and the thin-walled sleeve is arranged on the metal pipe In the connection end of the pipe, the flange is on the end face of the metal pipe end, and it also includes a union nut and a compression sleeve (GB1008313A, international classification number F16L19/06, 1965).

The branch pipe is provided with an externally threaded area, an internal bore with a cylindrical surface, an internal trapezoid perpendicular to the axis, and an internal tapered surface facing the free end of the branch pipe and opening from the side of the free end. The compression sleeve is provided in the form of a sleeve having an outer tapered surface and is made of a deformable polymeric material, one end of the tube of polymeric material is embedded in the inner bore of the branch pipe, the collar of the sleeve passes through the top of the sealing ring on the inner trapezoid. And the union nut is screwed on the branch pipe. A compression sleeve is snap-fitted on the outer surface of one end of the polymeric tube and squeezed along the sides opposite the shaft between the inner taper of the branch and the radial annular projection inside the union nut.

When the union nut is tightened, the compression sleeve deforms due to the interaction between its tapered surface and the branch pipe, compressing around the metal pipe end to ensure a reliable and reliable connection between the metal pipe end and the pipe fitting tightness.

The use of this known solution is to connect pipe fittings with metal pipe ends. When connecting polymeric pipes using this solution, the reliability of the connection and a high degree of load-bearing capacity cannot be guaranteed. The tube is sandwiched between smooth surfaces in the longitudinal direction, and when the internal pressure of the conveyed medium increases, the end of the tube will fall off from the branch pipe of the pipe fitting.

A known joint connecting pipe fittings (straight joints, pipe joints, elbows, tees) and polymeric material pipes includes branch pipes arranged on the hard body of pipe fittings, union nuts and compression sleeves (CN2560807Y, international classification number F16L21/00, 2003).

The branch pipe is provided with an externally threaded area, an internal bore with a cylindrical surface, an internal trapezoid perpendicular to the axis, and an internal tapered surface facing the free end of the branch pipe and opening from the side of the free end.

The union nut is provided with an inner radial annular protrusion having a tapered surface facing into the cavity of the union nut and disposed along the inner edge of the annular protrusion. The compression sleeve is arranged in the form of a cylinder, with an outer conical slope along its two sides, and some longitudinal grooves are arranged on this side of the tube body, and this part is made into a petal shape.

One end of the tube of polymeric material fits into the bore of the branch tube and pushes against the inner trapezoid. The union nut is screwed onto the branch pipe, while the compression sleeve is snap-fitted on the outer surface of one end of the polymeric tube, along the sides opposite the shaft, at the inner taper of the branch pipe and the radially annular raised tapered surface inside the union nut compression between.

When the union nut is tightened, the compression sleeve deforms and compresses both sides of the end in the direction of the shaft. In this case the petals straighten out in the direction of the axis, penetrate deep into the surface of the polymer tube, and in order to increase the reliability of the connection, additional protrusions are provided on the inner surface of the petals.

However, this kind of connector cannot guarantee good reliability and load-bearing capacity of its connection, because the tension nut cannot be tightened to a great extent, so when increasing the tension of the tension nut, the tube made of polymer material, especially Tubes made of polypropylene or polyethylene, including multi-layer tubes, can be deformed, which can destroy the tightness of the connection. Once the pressure of the conveying medium is too high, one end of the polymeric material tube may pop out of the branch pipe.

Contents of the invention

The technical result of the present invention is the extension of a device for connecting the solid metal alloy body of a plumbing fitting with a polymeric material, including a pipe made of polyethylene or polypropylene. This device has the characteristics of high sealing reliability, high load-carrying capacity, long service life, etc., and will not increase the hydraulic loss due to the narrowing of the flow section at the connection area between the pipe fitting and the polymer material pipe.

To achieve this technical achievement there is provided a joint for connecting a pipe fitting to a pipe of polymeric material, comprising:

Branch pipes set on the solid body of pipe fittings;

an outwardly knurled, thin-walled sleeve disposed within the connecting end of the polymeric tube, the knurled abutting against the end face of one end of the polymeric tube;

Union nut, compression sleeve and seal ring.

The branch pipe is provided with an externally threaded area, an internal bore with a cylindrical surface, an internal trapezoid perpendicular to the axis, and an internal cone facing the free end of the branch pipe and openable from the side of the free end.

The union nut is provided with an inner radial annular protrusion, and the surface of the protrusion is a conical surface, and the conical surface faces the cavity of the union nut and is arranged along the inner edge of the annular protrusion.

One end of the polymeric material tube is embedded in the inner hole of the branch pipe, and the collar of the sleeve is pushed against the inner trapezoidal piece through the sealing ring.

The union nut is screwed on the branch pipe, while the compression sleeve is made of metal alloy. The surface of the compression sleeve has no gap and is fitted with the outer surface of the pipe. Along the two sides opposite to the axis, the inner taper and Compression takes place between the radially annular raised conical surfaces inside the nozzle, and the edges are deformed inwardly of the axis along both sides opposite the axis, allowing the edges to penetrate deep into the material at the end of the tube of polymeric material.

The joint for connecting pipe fittings with polymeric material pipes made according to the invention differs from the above-mentioned known solutions in that the present invention has a thin-walled sleeve, a sealing ring, and this difference also lies in the position of the thin-walled sleeve and the sealing ring and the shape of the compression sleeve.

In the preferred embodiment of the present invention, the inner surface of the compression sleeve is cylindrical, and the outer surface of the compression sleeve is arc-shaped when viewed from the longitudinal section, and the arc-shaped outer surface is along the circumference of the end face of the compression sleeve. connected to its cylindrical inner surface. Compression sleeves can also be provided in other shapes as shown below.

The polymeric material tube can be arranged in multiple layers, with the intermediate layer being made of a metal alloy and the sealing ring being made of a dielectric material.

Compression sleeves can be made of brass or stainless steel. The thin-walled casing can also be made of brass or stainless steel, and the selection of sealing ring materials includes ethylene-propylene-diene rubber, nitrile rubber, Teflon, and silicone.

In order to solve the tasks proposed by the above-mentioned invention, a pipe fitting can be connected to a pipe of polymeric material, characterized in that:

Solid body with branch pipes;

an outwardly knurled, thin-walled sleeve capable of being placed inside the connecting end of the polymeric tube, the knurled abutting against the end face of the polymeric tube end;

Union nut, compression sleeve and sealing ring.

The branch pipe is provided with an externally threaded area, an inner hole with a cylindrical surface, and an inner trapezoid perpendicular to the axis. When one end of the polymeric material pipe is inserted into the inner hole of the branch pipe, the convex edge of the thin-walled sleeve is pushed to the the internal trapezoid. The branch pipe is also provided with an inner tapered surface facing the free end of the branch pipe and opening from the side of the free end.

The union nut is provided with an inner radial annular protrusion, and the surface of the protrusion is a conical surface, and the conical surface faces the cavity of the union nut and is arranged along the inner edge of the annular protrusion.

The union nut is screwed on the branch pipe, while the compression sleeve is made of metal alloy, and there is no gap on the surface of the compression sleeve. When the outer surface of one end of the polymeric tube is engaged with the compression sleeve, it is compressed between the inner taper of the branch pipe and the radially annular raised taper of the inside of the union nut along both sides opposite the axis, so that the edge along the The sides opposite the axis are deformed inwardly of the axis, causing the edge to penetrate deep into the material at the end of the tube of polymeric material.

The pipe fittings made according to the invention, which can be connected to polymer material pipes, differ from the above known solutions in that the present invention has a thin-walled sleeve, a sealing ring, and this difference also lies in the thickness of the thin-walled sleeve and the sealing ring. location and shape of the compression sleeve.

In the preferred embodiment of the pipe fitting, the inner surface of its compression sleeve is cylindrical, and the outer surface of the compression sleeve is arc-shaped when viewed from the longitudinal section, and the arc-shaped outer surface is on the end surface of the compression sleeve. The top is connected to its cylindrical inner surface along the circumference.

As mentioned above, compression sleeves can be made of brass or stainless steel. The thin-walled casing can also be made of brass or stainless steel, and the selection of sealing ring materials includes ethylene-propylene-diene rubber, nitrile rubber, Teflon, and silicone.

Description of drawings

A joint for connecting straight-through plumbing fittings to polymeric pipes is described in detail with specific embodiments.

Fig. 1 is a longitudinal section of the present invention,

Figure 2 is a longitudinal section of a compression sleeve made in accordance with a preferred embodiment of the present invention.

Detailed ways

A joint for connecting straight-through plumbing fittings to polymeric pipes comprises branch pipes 2 arranged on the solid body 1 of the straight-through part (Fig. 1), a thin-walled sleeve 3 with a knurled edge 4 facing outwards at one end, The thin-walled sleeve 3 is arranged inside the connecting end of the polymeric material pipe 5, and the flange 4 of the sleeve 3 abuts on the end face 6 of one end of the polymeric material pipe 5, and also includes a union nut 7, a compression sleeve 8 and a sealing ring 9.

The branch pipe 2 is provided with an externally threaded area 10, an inner hole 11 with a cylindrical surface, an internal trapezoid 12 perpendicular to the axis, and the branch pipe 2 is also provided with an inner cone facing the free end 14 of the branch pipe 2 and opening from the side of the free end 14 Surface 13.

The union nut 7 is provided with an inner radial annular protrusion 15 with a conical surface, said conical surface 16 facing into the cavity of the union nut 7 and arranged along the inner edge of the annular protrusion 15 . The union nut 7 is screwed onto the branch pipe 2 via its external threaded region 10 .

One end of the pipe 5 is embedded in the inner hole 11 of the branch pipe 2 , and the flange 4 of the sleeve 3 is supported on the inner trapezoid 12 through the sealing ring 9 .

The compression sleeve 8 is made of a metal alloy, and the compression sleeve 8 has no gaps on its surface. The compression sleeve 8 has a cylindrical inner surface 17 ( FIG. 2 ). Seen from a longitudinal section, the outer surface 18 of the compression sleeve 8 is arc-shaped. The circumference is connected to its cylindrical inner surface 17.

The compression sleeve 8 (Fig. 1) is engaged with the outer surface of one end of the pipe 5, and along the two sides (ends 19) opposite to the shaft, there is a radial annular protrusion 15 on the inner tapered surface 13 of the branch pipe 2 and the inside of the union nut 7 The compression is carried out between the conical surfaces 16 of the tube, so that the edge is deformed inwardly along the axis of the compression sleeve 8 along the two sides opposite to the axis, so that the edge penetrates into the material at one end of the polymeric material tube 5 (the depth is 0.3-0.4 mm, Figure 1 shows the compression sleeve 8) in the deformed state.

The compression sleeve 8 does not only have the shape described above. The shape of the compression sleeve can also be a straight sleeve in the form of a pipe segment with a circular end surface perpendicular to the axis (this solution of the compression sleeve 8 is not shown in the figure). No longitudinal grooves are provided on the compression sleeve, ie the compression sleeve 8 has a continuous form in the direction forming its smooth surface, in which direction the material is continuously pulled. The outer annular bevel is provided for joining the inner conical surface 13 of the branch pipe 2 with the conical surface 16 of the inner radial annular projection 15 of the union nut 7 . One or several annular or broken grooves can be set on the inner surface and/or outer surface of the compression sleeve 8, and most of the grooves are perpendicular to the axis of the compression sleeve 8, so as to facilitate the deformation of the compression sleeve 8 .

The connecting pipe made of polymeric material can be arranged in several layers (not shown in the figure), with the intermediate layer made of a metal alloy. In order to prevent potential transmission along the metal layer of the pipe, the sealing ring 9 is made of a dielectric material. The basic function of the sealing ring 9 is to ensure the tightness of the connection and prevent the multi-layer pipe from delamination under the influence of the pipeline conveying medium. The sealing ring 9 can be an ordinary ring with a horizontal end face (rectangular cross-section), can be a circular ring or a ring with other cross-sections, and can have grooves to set the flange 4 of the thin-walled sleeve 3 . The sealing ring 9 can be made of ethylene-propylene-diene rubber, nitrile rubber, Teflon, silica gel or other elastic sealing materials. When the joint of the connecting pipe connected does not contain a conductive layer, a conductive material can also be used production.

Both the compression sleeve 8 and the thin-walled sleeve 3 can be made of brass or stainless steel. Other parts can be made from materials traditionally used to make plumbing fittings. Considering the construction of the fabricated parts, the fabrication of the parts shall be carried out by reference to known processes and acceptable materials.

When assembling, the thin-walled sleeve 3 is pre-installed into one end of the pipe 5 until the flange 4 bears against the end 6 . The sealing ring 9 is placed in the bore 11 of the branch pipe 2 . The union nut 7 and the compression sleeve 8 are sleeved on one end of the pipe 5 successively. One end of the pipe 5 is put into the inner hole 11 of the branch pipe 2 until it is supported. At this time, the sealing ring 9 has been moved until it meets the inner trapezoidal piece 12, and is pressed to the longitudinal direction of the branch pipe to ensure the sealing performance of the overall connection of the end. The union nut 7 is screwed onto the branch pipe 2 via its external threaded region 10 . The compression sleeve 8 is compressed and deformed between the inner conical surface 13 of the branch pipe 2 and the conical surface 16 of the radial annular protrusion 15 inside the union nut 7 . As before, this allows for a secure connection of the pipe fitting to the polymer pipe.

Tubes made of different polymeric materials can be joined. For example, tubes made of various polypropylenes or polyethylenes, including cross-linked polyethylenes, can be used as solid tubes, or as indicated above, multi-layered tubes.

The listed inventive embodiments are not exhaustive. Other embodiments of the invention are possible.

Claims (7)

1. A joint for connecting a pipe fitting to a pipe of polymeric material, comprising: Branch pipes set on the solid body of pipe fittings; an outwardly knurled, thin-walled sleeve disposed within the connecting end of the polymeric tube, the knurled abutting against the end face of one end of the polymeric tube; Union nut, compression sleeve and sealing ring; The branch is provided with an externally threaded area, an inner hole with a cylindrical surface, an internal trapezoid perpendicular to the axis, and an internal cone facing the free end of the branch and openable from the side of the free end; The union nut is provided with an inner radial annular protrusion, and the surface of the protrusion is a conical surface, and the conical surface faces the cavity of the union nut and is arranged along the inner edge of the annular protrusion; One end of the polymer material tube is embedded in the inner hole of the branch pipe, and the convex edge of the sleeve is pushed against the inner trapezoidal piece through the sealing ring; The union nut is screwed on the branch pipe; The compression sleeve is made of metal alloy, the surface of the compression sleeve has no gap, and it is fitted with the outer surface of the pipe. Along the two sides opposite to the axis, the inner cone surface of the branch pipe and the radially annular raised cone inside the adapter Compression is performed between the profiled faces, and the edge is deformed inwardly of the axis along both sides opposite the axis, allowing the edge to penetrate deep into the material at the end of the tube of polymeric material. 2. The joint according to claim 1, wherein the inner surface of the compression sleeve is cylindrical, and the outer surface of the compression sleeve is arc-shaped when viewed from the longitudinal section, and the arc-shaped outer surface is in the shape of the compression sleeve. The end face of the tube is connected to its cylindrical inner surface along the circumference. 3. A joint as claimed in claim 1 or claim 2, characterized in that the tube of polymeric material is arranged in multiple layers, with the intermediate layer being made of a metal alloy and the sealing ring being made of a dielectric material. 4. The joint according to claim 1 or claim 2, characterized in that the compression sleeve can be made of brass or stainless steel, the thin-walled sleeve can also be made of brass or stainless steel, and the sealing ring is made of Material options include ethylene-propylene-diene rubber, nitrile rubber, Teflon, and silicone. 5. A pipe fitting connectable to a pipe of polymeric material comprising: Solid body with branch pipes; an outwardly knurled, thin-walled sleeve capable of being placed inside the connecting end of the polymeric tube, the knurled abutting against the end face of the polymeric tube end; Union nut, compression sleeve and sealing ring; The branch pipe is provided with an external thread area, an inner hole with a cylindrical surface, and an inner trapezoid perpendicular to the axis. The inner trapezoidal part, the branch pipe is also provided with an inner tapered surface facing the free end of the branch pipe and opening from the side of the free end; The union nut is provided with an inner radial annular protrusion, and the surface of the protrusion is a conical surface, and the conical surface faces the cavity of the union nut and is arranged along the inner edge of the annular protrusion; The union nut is screwed on the branch pipe; The compression sleeve is made of metal alloy, there is no gap on the surface of the compression sleeve, when the outer surface of one end of the polymeric material tube is combined with the compression sleeve, along the two sides opposite to the axis, in the taper inside the branch pipe and the connecting pipe Compression between the radially annular raised conical surfaces inside the nut deforms the edge inwardly of the axis along both sides opposite the axis, allowing the edge to penetrate deep into the material at the end of the tube of polymeric material. 6. The accessory according to claim 5, wherein the inner surface of the compression sleeve is cylindrical, and the outer surface of the compression sleeve is arc-shaped when viewed from the longitudinal section, and the arc-shaped outer surface is in the shape of the compression sleeve. The end face of the tube is connected to its cylindrical inner surface along the circumference. 7. The accessory according to claim 5 or claim 6, characterized in that the compression sleeve can be made of brass or stainless steel, the thin-walled sleeve can also be made of brass or stainless steel, and the sealing ring is made of Material options include ethylene-propylene-diene rubber, nitrile rubber, Teflon, and silicone.