阅读说明：本技术 一种卡压式厚壁管件 (Clamping and pressing type thick-wall pipe fitting ) 是由 陈卫东 于 2021-03-23 设计创作，主要内容包括：本发明公开了一种用于厚壁管的卡压式厚壁管件,具有挤压承口(1)、插管承口(2)和管端限位部(3),挤压承口(1)设置在插管承口(2)靠近管插入孔的一侧,所述管件的管壁为由软钢制成的厚壁,所述软钢的流变强度等于或小于310N/mm～(2)；所述挤压承口(1)的管壁厚度相比管件的其他部位的管壁至少不减薄；采用新材料、新结构解决了用于厚壁管的卡压式厚壁管件缩径困难、成本高、管壁被齿卡损伤导致过早蚀穿的问题。(The invention discloses a clamping and pressing type thick-wall pipe fitting for a thick-wall pipe, which is provided with an extrusion bell mouth (1), an insertion pipe bell mouth (2) and a pipe end limiting part (3), wherein the extrusion bell mouth (1) is arranged on one side, close to a pipe insertion hole, of the insertion pipe bell mouth (2), the pipe wall of the pipe fitting is thick-wall made of mild steel, and the rheological strength of the mild steel is equal to or less than 310N/mm 2 (ii) a The thickness of the pipe wall of the extrusion socket (1) is compared with that of the pipe fittingThe pipe walls of other parts are not thinned at least; the new material and the new structure are adopted to solve the problems that the clamping and pressing type thick-wall pipe fitting for the thick-wall pipe is difficult to reduce in diameter and high in cost, and the pipe wall is damaged by the tooth clamps to cause premature erosion.)

1. For thick-wall pipeThe card pressure formula thick wall pipe fitting of (2) has extrusion bellmouth (1), intubate bellmouth and spacing portion of pipe end (3), and extrusion bellmouth (1) sets up the one side that is close to the pipe insertion hole in intubate bellmouth (2), its characterized in that: the pipe wall of the pipe fitting is a thick wall made of mild steel, and the rheological strength of the mild steel is equal to or less than 310N/mm²(ii) a The thickness of the pipe wall of the extrusion bell mouth (1) is at least not reduced compared with the pipe wall of other parts of the pipe fitting.

2. A slip thick-walled tube as claimed in claim 1 wherein the mild steel is a rare earth mild steel material with excellent rheological properties consisting essentially of: about 0.0025 to 0.006 wt% carbon, about 0.005 to 0.025 wt% silicon, about 0.05 to 0.15 wt% manganese, about 0.003 to 0.02 wt% titanium, about 0.03 to 0.07 wt% vanadium, about 0.005 to 0.8 wt% yttrium, sulfur 0.015 wt% or less, phosphorus 0.020 wt% or less, nitrogen 0.006 wt% or less, and the balance iron and inevitable impurities, the mild steel having a rheological strength of 210N/mm or less²。

3. The clamp-on thick-walled tube according to claim 1, wherein the mild steel is an ultra-low carbon mild steel material with excellent rheological properties, consisting essentially of: about 0.002-0.005 wt% carbon, about 0.004-0.030 wt% silicon, about 0.06-0.20 wt% manganese, about 0.006-0.040 wt% aluminum, about 0.04-0.06 wt% titanium, about 0.03-0.1 wt% vanadium, 0.002 wt% or less sulfur, 0.015 wt% or less phosphorus, and the balance iron and inevitable impurities, the rheological strength of the mild steel is equal to or less than 235N/mm²。

4. A clamp thick-walled tube for thick-walled tubes according to any of claims 1 to 3, further comprising a tube port inner wrap ring (4), characterized in that: at least one extrudable tooth ring (5) and a sealing element (6) which are made of composite materials are arranged in the pipe fitting port inward rolling circular ring (4); the squeezable toothed ring (5) comprises a hard elastic toothed ring and elastic plastic (8) coated outside the elastic toothed ring.

5. The clamp thick-walled tube of claim 4, wherein: the structure of coating the elastic plastic (8) outside the hard elastic toothed ring is one or more of completely rubber-coated toothed ring, non-rubber-coated toothed ring outer ring surface, rubber-coated toothed ring inner ring surface or rubber-coated toothed ring side surface (82);

the toothed ring is completely encapsulated, namely the hard elastic toothed ring is completely wrapped in the elastic plastic material, and the hard elastic toothed ring cannot contact with an external medium;

the outer ring surface of the toothed ring is not coated with rubber, namely the outer ring surface of the hard elastic toothed ring adjacent to the pipe fitting is not coated with the elastic plastic material, but the outer ring surface of the hard elastic toothed ring is directly exposed and directly attached to the inner wall of the pipe fitting;

the inner ring surface of the toothed ring is encapsulated, namely the hard elastic toothed ring is wrapped in the direction of the binding surface of the outer wall of the thick-wall pipe, and all the blade teeth of the hard elastic toothed ring are hermetically wrapped in a rubber material before the hard elastic toothed ring is extruded with the binding surface of the pipe;

the side surfaces of the toothed ring are encapsulated, namely the left side surface and the right side surface of the hard elastic toothed ring in the radial carving direction are encapsulated;

the hard elastic toothed ring is an elastic steel toothed ring which is a circumferentially continuous integral split ring, and the integral split ring is provided with a toothed ring opening part (56).

6. The clamp thick-walled tube of claim 4, wherein: the hard elastic toothed ring, the elastic plastic (8) coated outside the elastic toothed ring and the sealing piece (6) are made into an integral toothed ring composite self-sealing rubber ring.

7. The clamp thick-walled tube of claim 5, the resilient steel toothed ring comprising an annular continuation (51) and a plurality of teeth uniformly arranged on the annular continuation (51) along its circumference, wherein each tooth is directed in the direction of the thick-walled tube body and is radially symmetrical with respect to a radial plane of the annular continuation (51); or the elastic steel toothed ring comprises an annular continuous part (51), the annular continuous part (51) is an obliquely-opened integral split ring, a plurality of cutting openings (57) are symmetrically formed along the annular continuous part (51) and are uniformly distributed, a plurality of arc-shaped long rings (52) are uniformly distributed among the cutting openings (57), and each arc-shaped long ring (52) points to the direction of the thick-wall pipe (7) and is radially symmetrical relative to a radial plane of the annular continuous part (51) to be in a U shape.

8. The clamp-on thick-walled tube according to claim 4, characterized in that the seal (6) is a profiled ring seal (62) provided with a water stop ring or an O-ring seal (63).

9. A clamp thick-walled tube as claimed in any one of claims 1 to 8, wherein: in the pipe socket (2), the pipe socket diameter of the side adjacent to the extrusion socket (1)Diameter of the spigot of the intubation tube compared with the limit part (3) of the adjacent tube endIs large.

Technical Field

The invention relates to a clamping and pressing type thick-wall pipe fitting which is suitable for sealing and clamping and pressing type connection of a thick-wall pipeline or an ultra-thick-wall pipeline.

Background

In the prior art, for the remote transportation of fluid media, especially for the transportation of chemicals, fuels, gases including water, oil and natural gas, the ends of pipes are required to be mechanically connected in a sealing manner to form a pipeline system.

In the pipeline connection technology, the extrusion of the metal pipe is called as clamping pressure connection or mechanical socket pressing interface connection, so that the durability of connection sealing can be better kept. However, at present, the application of the connection mode is the clamping and pressing type connection of the thin-wall pipe in more than 99 percent. This is because thin-walled tubes are more suitable for deforming necks under mechanical forces. The connection technology is very inconvenient to apply to thick-wall pipes, the currently used materials for manufacturing clamping and pressing pipe fittings are larger in pressing force required during deformation than thin-wall pipes and pipe fittings due to the fact that the wall thicknesses of the thick-wall pipes and the pipe fittings are larger, pressing can be performed only under the action of very large mechanical force theoretically, and the ultrahigh-pressure and very heavy extrusion type tools are used, so that the connection technology is completely unrealistic in engineering and cannot be operated by manpower at present. In the installation of pipeline, because receive the restriction of pressfitting extrusion force instrument ability, do not have at present to block the extrusion region of pressing the pipe fitting and be the card pressure formula connection technology of thick wall and connecting pipe also is the thick wall simultaneously.

Hitherto, the technique of joining thick-walled pipes by extrusion has been concerned, including the solution of reducing the wall thickness locally at the extrusion by using a thick-walled fitting extrusion section, reducing the mechanical forces required during extrusion, thereby satisfying the usual extrusion tool applications. However, the technology is researched from the difference of the extrusion structure technology, is practically not different from thin-wall extrusion, still belongs to a thin-wall extrusion structure, and cannot eliminate the defect that micro-springback between thin-wall interfaces is easy to loose.

The pipe fitting with the tooth ring edge teeth has the obvious defect that the outer environment medium reaches an extrusion area due to the fact that the tooth ring edge teeth arranged at the extrusion position in an anti-pulling mode cut and damage the outer wall of the pipe and the like, and then the local area damaged by the extrusion area is eroded prematurely, and the problem that the thick-walled pipe is partially eroded in advance due to the fact that the damaged part is not protected by an existing common structure is solved.

In the local thinning technology of the extrusion area applied in the prior art, the relevance between the structure thickness of other parts of the thick-wall pipe fitting and the extrusion opening technology is not great. The applicant finds that no precedent exists in the world for adopting the extrusion type thick-wall pipe fitting at the compression joint part, and the fundamental reason is that the universal material used for manufacturing the clamping and pressing type pipe fitting is difficult to reduce due to higher strength, so that the practicability and feasibility in extrusion type connection are lost.

In addition, in the prior art, if the thickness of a clamping and pressing pipe fitting of a common thin wall is increased to 2.6mm and the wall thickness of an insertion pipe is 10mm, the extrusion type pipe joint is extruded by a traditional clamping and pressing tool and is not moved, so that the use value is not high; however, the development of special clamping and pressing tools for the purpose cannot be realized at present in the material science and the permission of manual tool weight.

On the other hand, the applicant finds that based on the requirement of the industry on cost reduction, the clamping and pressing type thick-wall pipe fitting should not adopt metal materials which have the performance meeting the requirement and are higher in price, such as stainless steel, copper, aluminum and the like, and the performance of mild steel which is relatively low in price is improved through a good smelting process technology, so that a new material is developed for low-cost manufacturing.

Therefore, based on the above research, the applicant has developed a press-fitting type pipe fitting using a new material and a new structure by a technical breakthrough in the production process of the new material, thereby solving the above problems.

Disclosure of Invention

The invention aims to provide a clamping and pressing type thick-wall pipe fitting which can be used for sealing and clamping and pressing type connection of a thick-wall pipeline or an ultra-thick-wall pipeline, has the advantages of simple structure, cheap material and convenient installation, can keep long-term sealing performance, can obviously reduce the manufacturing and installation cost, prolongs the service life and prevents corrosion and penetration.

The invention provides the following technical scheme:

a clamping and pressing type thick-wall pipe fitting for a thick-wall pipe is provided with an extrusion bellmouth, an insertion pipe bellmouth and a pipe end limiting part, wherein the extrusion bellmouth is arranged on one side of the insertion pipe bellmouth close to a pipe insertion hole; the pipe wall of the pipe fitting is a thick wall made of mild steel, and the rheological strength of the mild steel is equal to or less than 310N/mm²(ii) a The pipe wall thickness of the extrusion bellmouth is at least not reduced compared with the pipe wall of other parts of the pipe fitting.

According to the preferred embodiment of the invention, two chemical formula components for smelting and manufacturing mild steel are also disclosed, namely a rare earth mild steel material and a vanadium-titanium low-carbon mild steel material. The two soft steel materials have excellent metal cold rheological property, ductility, toughness, machinability, deep cooling and low temperature resistance and other excellent performances, and can be used for producing the clamping and pressing type thick-wall pipe fitting.

The preferable rare earth mild steel material with excellent rheological property mainly comprises the following components: about 0.0025 to 0.006 wt% carbon, about 0.005 to 0.025 wt% silicon, about 0.05 to 0.15 wt% manganese, about 0.003 to 0.02 wt% titanium, about 0.03 to 0.07 wt% vanadium, about 0.005 to 0.8 wt% yttrium, sulfur 0.015 wt% or less, phosphorus 0.020 wt% or less, nitrogen 0.006 wt% or less, and the balance iron and inevitable impurities, the mild steel having a rheological strength of 210N/mm or less²。

An ultra-low carbon mild steel material with excellent rheological properties is preferred, which mainly comprises the following components: about 0.002-0.005 wt% carbon, about 0.004-0.030 wt% silicon, about 0.06-0.20 wt% manganese, about 0.006-0.040 wt% aluminum, about 0.04-0.06 wt% titanium, about 0.03-0.1 wt% vanadium, 0.002 wt% or less sulfur, 0.015 wt% or less phosphorus, and the balance iron and inevitable impurities, the rheological strength of the mild steel is equal to or less than 235N/mm²。

The chemical formula of the two types of mild steel is based on ultralow-carbon low-silicon, manganese, phosphorus and sulfur, nitrogen and inevitable few other impurities are strictly controlled, and the novel ultralow-carbon mild steel material mainly containing iron element is modified by alloy and rare earth elements to obtain two types of high-quality mild steel, which has good metal rheological property and rheological strength equal to or less than 310N/mm²It has good ductility and toughness, cold resistance and low-temperature embrittlement resistance, and can be used for making thick-wall pipe, and further making it into said clamping-pressing type thick-wall pipe.

Preferably, the clamping and pressing type thick-wall pipe fitting is directly formed by a thick-wall mild steel pipe through an expansion process; the cross section of the extrusion bellmouth is circular; the extrusion bellmouth is cylindrical.

The clamping and pressing type thick-wall pipe fitting can be subjected to anti-corrosion surface treatment, so that the pipe fitting has good chemical corrosion resistance;

the clamping and pressing type thick-wall pipe fitting is suitable for connecting the galvanized steel pipe and the pipe with the surface coated with the anticorrosive steel pipe, and the thickness range of the metal pipe wall of the pipe comprises: the wall thickness of the pipe fitting with the pipe diameter DN10-DN25 is not less than 2.6mm, the wall thickness of the pipe fitting with the pipe diameter DN32 or above is not less than 3.0mm, and the pipe fitting can be used for extruding and connecting steel pipes with the wall thickness range of 3.0mm-30 mm.

In a preferred technical scheme of the invention, the clamping and pressing type thick-wall pipe fitting further comprises a pipe fitting port inward-rolling circular ring, and at least one extrudable tooth ring and a sealing element made of composite materials are arranged in the pipe fitting port inward-rolling circular ring; preferably, the squeezable toothed ring comprises a hard elastic toothed ring and elastic plastic coated outside the hard elastic toothed ring.

Preferably, the hard elastic toothed ring is made of stainless steel;

preferably, the hard elastic toothed ring is an extruded stop toothed ring, and the toothed ring is provided with at least one edge tooth; the hard elastic toothed ring is arranged in the extrusion bell mouth, and when the thick-wall pipe is inserted and then extruded and locked, the blade teeth pierce the sealing wrapping layer/protective layer of the thick-wall pipe and are carved into the pipe wall of the thick-wall pipe so as to ensure the axial fixation of extrusion connection and prevent the pipe end from being pulled out; the elastic plastic coated outside the hard elastic toothed ring and the punctured sealing material form all new extrusion sealing on the damaged part under the radial pressure; meanwhile, the clamping and pressing type thick-wall pipe fitting is made of mild steel with good rheological property, so that metal in the extrusion socket does not rebound after being extruded, the generation of gaps is reduced, and the stability of extrusion sealing is ensured; the combination of the above characteristics can protect the interface, avoid the corrosion of the external environment, increase the safety degree and prolong the service life.

Preferably, the sealing element of the clamping thick-walled tube is located in the same segment as the compressible ring gear, preferably in the section of the compression socket.

The preferable technical scheme is that the hard elastic toothed ring, the elastic plastic coated outside the elastic toothed ring and the sealing piece are made into an integral toothed ring composite self-sealing rubber ring.

One preferred technical solution is that the hard elastic toothed ring, the elastic plastic coated outside the elastic toothed ring and the sealing member are pre-assembled components.

The preferable technical scheme is that the toothed ring is completely encapsulated, which means that the extrudable toothed ring made of composite materials is completely wrapped in the elastic plastic material by the steel hard elastic toothed ring, and the steel hard elastic toothed ring cannot contact with an external corrosive medium.

Preferably, another technical scheme is that the outer ring surface of the toothed ring is not encapsulated, which means that the hard elastic toothed ring in the extrudable toothed ring is not encapsulated by the elastic plastic material on the outer ring surface adjacent to the pipe fitting, but the hard elastic toothed ring is directly exposed and is directly attached to the inner wall of the pipe fitting.

The other preferable technical scheme is that the side surfaces of the toothed ring are encapsulated, and the method means that the left side surface and the right side surface of the hard elastic toothed ring in the extrudable toothed ring in the radial carving direction are encapsulated.

The other preferable technical scheme is that the inner ring surface of the toothed ring is encapsulated, namely the hard elastic toothed ring in the extrudable toothed ring is wrapped in the direction of the binding surface of the outer wall of the thick-wall pipe, and the edge teeth of the hard elastic toothed ring are completely encapsulated and wrapped in the rubber material before the hard elastic toothed ring is extruded with the binding surface of the pipe.

Preferably, the opening of the hard elastic toothed ring is sealed by fully encapsulating the toothed ring.

Preferably, the elastic plastic is a rubber elastomer, and has good water tightness; the elastic plastic is uniformly coated outside the hard elastic toothed ring along the radial circumference of the pipe fitting; the elastic plastic and the hard elastic gear ring are firmly attached through the composite coupling agent.

The hard elastic toothed ring is an elastic steel toothed ring made of stainless steel.

In a preferred embodiment, the elastic steel toothed ring comprises an annular continuous portion and a plurality of blade teeth uniformly arranged on the annular continuous portion along the periphery thereof, wherein each blade tooth points to the direction of the thick-walled pipe body and is symmetrical to the radial direction with respect to a radial plane of the annular continuous portion;

preferably, in another technical scheme, the elastic steel toothed ring comprises an annular continuous part, and the annular continuous part is an integral ring with an oblique opening;

preferably, a plurality of cutting openings are symmetrically formed along the annular continuous part, a plurality of arc-shaped long rings are uniformly distributed among the cutting openings, and each arc-shaped long ring points to the direction of the thick-wall pipe body and is radially symmetrical to form a U shape relative to a radial plane of the annular continuous part.

Preferably, each arc-shaped long ring is provided with a plurality of blade teeth extending along the radial direction;

preferably, each arc-shaped long ring is provided with directional blade teeth or a circumferential cutting edge root which is carved into the pipe wall or inclines for a certain angle relative to the radial direction; preferably the angle is inclined at 10-20 degrees to the radial direction; preferably, the angle of inclination of the blade teeth with respect to the radial direction is equal to the angle of inclination of the oblique opening of the annular continuous portion with respect to the radial direction.

After the elastic steel toothed ring is extruded by the periphery of the outer ring, the blade teeth are embedded into the outer wall of the thick-wall pipe, and an elastic sealing protection state is obtained.

The knife-edge tooth structure is an equivalent-effect knife-edge tooth structure which can be embedded into the outer wall of the thick-wall pipe under the pressure of radial contraction.

One preferable technical scheme comprises that the sealing element can adopt an O-shaped ring sealing element or a profiled ring sealing element;

the special-shaped annular sealing element is provided with a main body sealing ring part and a tail part between the main body sealing ring part and the pipe end limiting part, and the tail part comprises a self-sealing tail ring sealing element water stop ring;

preferably, the profiled annular seal is not limited to the above-described profiled structure, but may include a structure having an equivalent effect to enhance sealing performance.

The other preferable technical scheme comprises that the extrusion bell mouth section is subjected to reducing transition to an adjacent socket pipe bell mouth section and then subjected to reducing transition to a pipe section limiting position; an inward-rolling circular ring stop is arranged at the socket part of the pipe fitting.

The other preferable technical scheme comprises that the clamping and pressing type thick-wall pipe fitting for the thick-wall pipe comprises a circular pipe-shaped extrusion socket section, the diameter of the circular pipe-shaped extrusion socket section is changed to be transited to an adjacent insertion pipe socket, the diameter of the circular pipe-shaped extrusion socket section is changed to be transited to a pipe section limiting position, an inward-rolling circular ring stop is arranged at the pipe fitting socket, and at least one extrudable gear ring and a sealing piece which are made of composite materials are arranged in the extrusion socket section. In order to facilitate the insertion of the end part of the thick-wall pipe connecting pipe, the diameter phi 1 of the inserted pipe socket at the part adjacent to the extrusion socket 1 is larger than the diameter phi 2 of the inserted pipe socket at the front part adjacent to the end part. When the pipe is inserted into the pipe fitting bell mouth in place, the outer ring surface of the extrusion bell mouth is extruded towards the inward necking to form a good and firm connection joint.

The invention provides two high-quality mild steel materials which are obtained by modifying a new ultralow-carbon mild steel material taking an iron element as a main body through an alloy and a rare earth element, and have good metal rheological property and rheological strength of equal to or less than 310N/mm²It has good ductility and toughness, cold resistance and low-temperature embrittlement resistance, and can be used for making thick-wall pipe, and further making it into said clamping-pressing type thick-wall pipe. The interface metal material after the extrusion connection of the thick-wall pipe fitting caused by the mild steel has no resilience, the tooth cutting edge of the clamping and pressing ring is not loosened after being clamped and pressed, the pipe fitting pipe binding surface is compact, the anchoring force is stable, and the interface rigidity is high, which is the technical performance and the characteristic that the thin-wall extrusion interface does not have.

The wall thickness of the clamping and pressing type thick-wall pipe fitting in the extrusion bell mouth section is at least not lower than that of the pipe fitting insertion pipe bell mouth section and the pipe end limiting part section, and the soft steel material of the clamping and pressing type thick-wall pipe fitting is thick-wall instead of the meaning of wall thickness or thickening of common thin-wall pipe manufacturing pipe fittings and the like, so that the thin-wall pipe does not need to be thickened on the gear ring extrusion part deliberately locally as in the prior art, and the inner wall of the pipe fitting is thick, so that the clamping and pressing type thick-wall pipe fitting can bear longer-time fluid scouring and corrosion, advanced erosion of the pipe fitting caused by wall surface defects caused by improper processing and uneven wall thickness generated by stretching can be avoided, and the clamping and pressing type thick-wall pipe fitting is a technical performance and a characteristic which a thin-wall extrusion interface does not have.

The clamping and pressing type thick-wall pipe fitting for the thick-wall pipe is produced by adopting mild steel materials, has thick walls for preventing corrosion penetration, realizes a good forming process, does not have secondary mechanical cutting processing, and reduces the production cost. The clamping and pressing type thick-wall pipe fitting for the thick-wall pipe has the advantages that the rheological strength is equal to or less than 310N/mm²The thick-wall pipe fitting made of mild steel material not only reduces the mechanical force required by extrusion,still because mild steel takes place plastic deformation under the mechanical force effect of extrusion connection, hard material such as the brittle fracture deformation that high carbon steel etc. produced in the difference prior art, and make the kneck mild steel material after the extrusion have no resilience, but the cooperation extrusion ring gear compresses tightly the sealing protection at the local rupture point that sealing member and ring gear carve into the department, therefore the card is pressed the ring gear blade and is not become flexible, the laminating face of card pressure formula thick wall pipe fitting and thick wall pipe is inseparable, the anchor power is stable, interface rigidity is high, the effectual erosion penetration that prevents has prolonged the life of card pressure formula thick wall pipe fitting, show reduction in production cost.

Drawings

FIG. 1 is a schematic cross-sectional view of a clamping thick-walled tube of the present invention before being inserted into a pipe;

FIG. 2 is a schematic cross-sectional view of the clamp-press type thick-walled tube after the insertion tube is extruded;

FIG. 3 is a schematic structural view of the split elastic steel toothed ring of the present invention;

FIG. 4 is a schematic sectional view taken along line A-A of one embodiment of the split resilient steel ring gear of the present invention;

FIG. 5 is a bottom view of one configuration of the split resilient steel ring gear of the present invention;

FIG. 6 is a schematic view of another configuration of the split resilient steel ring gear of the present invention;

FIG. 7 is a schematic sectional view taken along line A-A of another configuration of the split resilient steel ring gear of the present invention;

FIG. 8 is a bottom view of an alternative configuration of the split resilient steel ring gear of the present invention;

FIG. 9 is a side view of an alternative construction of the split resilient steel ring gear of the present invention;

FIG. 10 is a schematic view of the encapsulated open elastomeric steel toothed ring of the present invention;

FIG. 11 is a side view of the encapsulated open elastomeric steel toothed ring of the present invention;

FIG. 12 is a bottom view of the encapsulated open elastomeric steel ring gear of the present invention;

FIG. 13 is a schematic cross-sectional view B-B of the encapsulated open elastomeric steel ring gear of the present invention;

FIG. 14 is a schematic view of one configuration of the contoured annular seal of the present invention;

FIG. 15 is a schematic cross-sectional C-C view of one configuration of the contoured annular seal of the present invention;

FIG. 16 is a cross-sectional view of a tooth ring composite self-sealing rubber ring of a profiled ring seal structure according to the present invention;

FIG. 17 is a cross-sectional view of a tooth ring composite self-sealing rubber ring of an O-ring seal configuration of the present invention;

wherein, 1, extruding a socket; 2. a cannula socket; 3. a pipe end limiting part; 4. a circular ring is rolled in the end opening of the pipe fitting; 5. the toothed ring can be pressed; 6. a seal member; 7. a thick-walled pipe; 8. elastic plastic cement; 51. an annular continuous portion of the resilient steel ring gear; 52. an arc-shaped long ring; 53. root of the blade tooth opening; 54. cutting teeth carved into the pipe wall; 55. an insertion portion protection seal portion; 56. a gear ring opening; 57. cutting off the opening; 61. an annular portion of the seal; 62. a profiled annular seal; 63. an O-ring seal; 81. opening a rubber-coated toothed ring; 82. encapsulating the side surface of the toothed ring; 83. and the inner ring surface of the toothed ring is encapsulated.

Detailed Description

The definition of the thick wall and the thin wall is defined, the current international definition has no clear standard, and the extrusion type pipeline system connection engineering adopted internationally at present is determined to be the thick wall only by common practice in the industry, the wall thickness of DN15 is more than 2.6mm, the wall thickness of DN100 is more than 3.5mm, the specification is DN 15-DN 100, the wall thickness of the pipe fittings at the extrusion part is generally thin-walled, the wall thickness is less than or equal to 2.0 mm, and the pipe fittings are generally considered to be extruded by thin-walled pipes.

The definitions of the term "thick-walled" pipe, as used in this application, are defined as follows: the wall thickness of DN15 pipe is more than 2.6mm, and the wall thickness of DN100 pipe is more than 3.5mm and is regarded as the thick wall; the wall thickness of the pipe fitting at the extrusion part is less than or equal to 2.0 mm and is determined as a thin wall.

The term "mild steel" as used in this application means a mild steel containing 0.002% to 0.10% carbon and not more than 0.50% Mn, which has low strength, low hardness and softness, good plasticity, and significant yield point/yield stage and plastic deformation under the action of external force.

The term "plastic" as used in this application includes plastics and rubber.

Examples

For better understanding of the above technical solutions, the following detailed descriptions will be made with reference to the drawings and specific embodiments of the specification, but the present invention is not limited to these specific embodiments.

As shown in fig. 1, a schematic diagram of a pipe inserting tube before extrusion of a clamp-press type thick-wall pipe fitting for connecting a thick-wall pipe 7 according to an embodiment of the present invention includes an extrusion socket 1, an insertion socket 2 and a pipe end limiting portion 3, wherein the extrusion socket 1 is disposed on one side of the insertion socket 2 close to a pipe inserting hole; the pipe wall thickness of the clamping and pressing type thick-wall pipe fitting in the section of the extrusion bell mouth 1 is at least not lower than the wall thickness of the section of the pipe insertion pipe bell mouth 2 and the section of the pipe end limiting part 3; the pipe wall of the pipe fitting is a thick wall made of mild steel, and the rheological strength of the mild steel is equal to or less than 310N/mm²Preferably, the mild steel has a rheological strength equal to or less than 235N/mm²Preferably, the mild steel has a rheological strength equal to or less than 210N/mm²；

As shown in fig. 2, the schematic diagram of the clamp-press type thick-wall pipe fitting for connecting the thick-wall pipe 7 in this embodiment after extrusion shows that the U-shaped toothed ring edge teeth 64 are carved into the surface of the thick-wall pipe 7, the elastic plastic on the surface of the extrusion edge teeth and the profiled ring-shaped sealing member 62 with a water stop ring completely fill the gap of the extrusion area, and the water stop ring 62 is pressed and sealed between the outer surface of the thick-wall pipe 7 and the inner wall of the area of the pipe socket 2 of the clamp-press type thick-wall pipe fitting under pressure; the tooth ring edge teeth 64 are carved into the surface edge teeth of the thick-wall pipe 7 to pierce the sealing wrapping layer/protective layer of the thick-wall pipe 7 and are carved into the pipe wall of the thick-wall pipe 7 so as to ensure the axial fixation of the extrusion connection and prevent the pipe end from being pulled out; the elastic plastic 8 and the punctured sealing material which are coated outside the hard elastic toothed ring form all new embedded part protection sealing parts 55 at the damaged part under radial pressure, and the damaged part of the sealing coating layer/protective layer of the thick-wall pipe 7 is extruded and sealed; because the extrusion socket is completely filled with the elastic material and has no gap, the pressure at the extrusion part of the clamping and pressing piece is stable, the cutting edge of the clamping and pressing toothed ring is not loosened, the binding surface of the clamping and pressing type thick-wall pipe fitting and the thick-wall pipe 7 is tight, and the sealing performance and the stability are high.

The applicant has found that by using a rheology equal to or less than 310N/mm²When the thick-wall pipe fitting made of the mild steel material is clamped and pressed for connection, the mechanical force required for reaching the yield point is obviously reduced, so that the clamping and pressing type thick-wall pipe fitting can be extruded by using a traditional clamping and pressing tool, and a good permanent locking and sealing effect is achieved.

The thickness of the pipe wall of the extrusion bell mouth 1 is at least not reduced compared with the pipe wall of other parts of the pipe fitting; because the soft steel material of the thin-walled pipe is thick-walled, the thin-walled pipe is not the meaning of manufacturing pipe fittings and the like or thickening of the common thin-walled pipe, the thin-walled pipe does not need to be thickened locally and deliberately at the extrusion part of the gear ring as in the prior art.

Moreover, the knife teeth of the clamping tooth ring at the clamping pressure joint in the prior art can be carved into the surface of the end opening of the thick-wall pipe 7 inserted into the pipe fitting, so that the extrusion part has damage, the corrosion resistance of the connecting part is reduced, and the service life of a pipeline system is adversely affected.

In the embodiment of the invention, as the mild steel is subjected to plastic deformation under the action of the mechanical force of extrusion connection, the mild steel material at the extruded interface has no resilience, and the metal material at the extruded part is easy to deform, so that the pressure at the extruded part of the clamping and pressing piece is stable, the cutting edge of the clamping and pressing tooth ring is not loosened, the binding surface of the clamping and pressing type thick-wall pipe fitting and the thick-wall pipe 7 is tight, the anchoring force is stable, and the interface rigidity is high, which is the technical performance and characteristics that the thin-wall or thick-wall thinning extrusion interface in the prior art does not have.

The clamping and pressing type thick-wall pipe fitting for the thick-wall pipe 7 in the preferred embodiment comprises a circular pipe-shaped extrusion bell mouth 1, a reducing transition is carried out on the circular pipe-shaped extrusion bell mouth 1 to an adjacent pipe-inserting bell mouth 2, the reducing transition is carried out to a pipe section limiting position, an inward-rolling circular ring stop is arranged on the part of the pipe-shaped extrusion bell mouth 1, and at least one composite material extrusion tooth ring 5 and a sealing piece 6 are arranged in the extrusion bell mouth 1. In order to facilitate the insertion of the end part of the thick-wall pipe 7 connecting pipe, the diameter phi 1 of the inserted pipe socket at the part adjacent to the extrusion socket 1 is larger than the diameter phi 2 of the inserted pipe socket 2 at the front part adjacent to the pipe end. When the pipe is inserted into the pipe fitting bell mouth in place, the outer ring surface of the extrusion bell mouth 1 is extruded towards the inward necking to form a good and firm connection joint.

In the preferred embodiment of the invention, two chemical formula components for smelting and manufacturing mild steel are also disclosed, namely a rare earth mild steel material and a vanadium-titanium low-carbon mild steel material. The two soft steel materials have excellent metal cold rheological property, ductility, toughness, machinability, deep cooling and low temperature resistance and other excellent performances, and can be used for producing the clamping and pressing type thick-wall pipe fitting.

The preferable rare earth mild steel material with excellent rheological property mainly comprises the following components: about 0.0025 to 0.006 wt% carbon, about 0.005 to 0.025 wt% silicon, about 0.05 to 0.15 wt% manganese, about 0.003 to 0.02 wt% titanium, about 0.03 to 0.07 wt% vanadium, about 0.005 to 0.8 wt% yttrium, sulfur 0.015 wt% or less, phosphorus 0.020 wt% or less, nitrogen 0.006 wt% or less, and the balance iron and inevitable impurities, the mild steel having a rheological strength of 210N/mm or less²Preferably, the rheological strength of the mild steel is 180-210N/mm²。

An ultra-low carbon mild steel material with excellent rheological properties is preferred, which mainly comprises the following components: about 0.002-0.005 wt% carbon, about 0.004-0.030 wt% silicon, about 0.06-0.20 wt% manganese, about 0.006-0.040 wt% aluminum, about 0.04-0.06 wt% titanium, about 0.03-0.1 wt% vanadium, 0.002 wt% or less sulfur, 0.015 wt% or less phosphorus, and the balance iron and inevitable impurities, the rheological strength of the mild steel is equal to or less than 235N/mm²。

Preferably, the rheological strength of the mild steel is 180-310N/mm²(ii) a Preferably, the rheological strength of the mild steel is 210-235N/mm²。

The chemical formula of the two types of mild steel is based on ultralow-carbon low-silicon, manganese, phosphorus and sulfur, nitrogen and inevitable few other impurities are strictly controlled, and the novel ultralow-carbon mild steel material mainly containing iron element is modified by alloy and rare earth elements to obtain two types of high-quality mild steel, which has good metal rheological property and rheological strength of 180-310N/mm²Is good inThe product has ductility and toughness, cold resistance and low temperature embrittlement resistance, and can be used for making thick-wall pipe and further processed into the clamping and pressing type thick-wall pipe fitting. Because the clamping and pressing type thick-wall pipe fitting for the thick-wall pipe is produced by adopting mild steel materials, the pipe fitting has the thick wall which can prevent corrosion penetration, the good forming process is realized, secondary mechanical cutting processing is not needed, the defects are reduced, and the production cost is reduced.

Preferably, the clamping and pressing type thick-wall pipe fitting is directly formed by punching through a thick-wall mild steel pipe by an expansion process; the cross section of the extrusion bellmouth 1 is circular; the extrusion bellmouth 1 is cylindrical.

The clamping and pressing type thick-wall pipe fitting can perform anti-corrosion surface treatment on the surface of mild steel, so that the pipe fitting also has good chemical corrosion resistance, prevents the pipe wall from being corroded by an abrasive medium, and prolongs the service life;

the clamping and pressing type thick-wall pipe fitting is suitable for the conventional common galvanized steel pipe and the thick-wall pipe 7 pipe connection of the surface coating anti-corrosion steel pipe, and the thickness range of the metal pipe wall of the pipe comprises: the wall thickness of the pipe fitting with the pipe diameter DN10-DN25 is not less than 2.6mm, the wall thickness of the pipe fitting with the pipe diameter DN32 or above is not less than 3.0mm, and the pipe fitting can be used for extruding and connecting steel pipes with the wall thickness range of 3.0mm-30 mm.

In a preferred embodiment of the present invention, as shown in fig. 1 and fig. 2, the clamping and pressing type thick-walled pipe further comprises a pipe port inward rolling circular ring 4, and at least one extrudable tooth ring 5 and a sealing member 6 made of composite materials are arranged in the pipe port inward rolling circular ring 4; preferably, the squeezable toothed ring 5 comprises a hard elastic toothed ring and elastic plastic 8 coated outside the hard elastic toothed ring.

Preferably, the hard elastic toothed ring is made of stainless steel; preferably, the hard elastic toothed ring is a pressed stop toothed ring, and the toothed ring is provided with at least one edge tooth; the hard elastic toothed ring is arranged in the extrusion bell mouth 1, when the thick-wall pipe 7 is inserted and extruded and locked, the blade teeth pierce the sealing wrapping layer/protective layer of the thick-wall pipe 7 and are carved into the pipe wall of the thick-wall pipe 7 so as to ensure the axial fixation of the extrusion connection and prevent the pipe end from being pulled out; the elastic plastic 8 coated outside the hard elastic gear ring and the punctured sealing material form all new extrusion sealing on the damaged part at the same time under the radial pressure; meanwhile, the clamping and pressing type thick-wall pipe fitting is made of mild steel with good rheological property, so that the metal in the extrusion bellmouth 1 does not rebound after being extruded, the generation of gaps is reduced, and the stability of extrusion sealing is ensured; the combination of the above characteristics can protect the interface, avoid the corrosion of the external environment, increase the safety degree and prolong the service life.

Preferably, the sealing element 6 of the clamping thick-walled tube is located in the same segment as the compressible ring gear 5, preferably in the section of the compression socket 1.

A preferred embodiment is that the toothed ring is completely encapsulated, which means that the extrudable toothed ring 5 made of composite material is completely wrapped inside the elastic plastic 8 material by a steel hard elastic toothed ring, and the steel hard elastic toothed ring is not contacted with an external corrosive medium.

Insert the sword tooth of the steel stereoplasm elasticity ring gear after the thick-walled pipe 7 card is pressed in the pipe fitting, by firmly block into thick-walled pipe 7 and encircle the body after, the original protection film of pipe wall, like the zinc layer of galvanized pipe can suffer destruction of certain degree in sword tooth card department, forms corrosion-resistant weak scar, but 8 materials of elastic plastic can make interface life-lengthening to the sealed protection of steel stereoplasm elasticity ring gear sword tooth and thick-walled pipe 7 scars.

Another preferred embodiment is that the outer ring surface of the toothed ring is not encapsulated, which means that the outer ring surface of the hard elastic toothed ring in the extrudable toothed ring 5 adjacent to the pipe fitting is not encapsulated by the elastic plastic 8 material, but the hard elastic toothed ring is directly exposed and directly attached to the inner wall of the pipe fitting, so that the attachment gap between the hard elastic toothed ring and the inner wall of the pipe fitting after the hard elastic toothed ring is installed in the pipe fitting can be reduced, and tight attachment is formed; therefore, after the section of the extrusion bell 1 is extruded by external force, the pressure can be directly transmitted to the hard elastic toothed ring, the blade teeth are clamped into the outer wall of the thick-wall pipe 7, and the pipe body is locked to prevent the thick-wall pipe 7 and the pipe fitting from being pulled out.

Another preferred embodiment is a gear ring side surface encapsulation 82, which means that the left and right side surfaces of the hard elastic gear ring in the extrudable gear ring 5 in the radial carving direction are encapsulated, so that the effective isolation of the contact part of the edge teeth of the gear ring and the sealing element 6 can be protected, the sealing element 6 cannot cause damage during installation and extrusion deformation, and the sealing reliability is ensured; the rubber coating of opposite side is sealed with the laminating of pipe fitting terminal surface simultaneously, and the bare face of outer ring of protection ring gear does not receive external environment influence, strengthens the outside sealing side protection effect of sword tooth.

Another preferred embodiment is a tooth ring inner ring surface encapsulation 83, which means that the hard elastic tooth ring in the extrudable tooth ring 5 is wrapped in the direction of the abutting surface with the outer wall of the thick-walled pipe 7, and the edge teeth of the hard elastic tooth ring are completely encapsulated in the rubber material before the hard elastic tooth ring is extruded with the abutting surface of the pipe. When the knife edge teeth are clamped into the outer surface layer of the thick-wall pipe 7, the punctured sealing surface is protected from being damaged again due to extrusion, and therefore the safety and the service life of pipe connection are improved.

Preferably, the ring gear opening 56 of the hard elastic ring gear is sealed by fully encapsulating the ring gear, so that the ring gear opening 56 is protected from being influenced by the environment, the deformation requirement during installation can be met, meanwhile, the damage to the sealing element 6 is avoided, and a special isolation retaining ring is arranged between the sealing element 6 and the hard elastic ring gear.

Preferably, the elastic plastic 8 is a rubber elastomer, and has good water tightness; the elastic plastic 8 is uniformly coated outside the hard elastic gear ring along the circumferential direction; the elastic plastic 8 and the hard elastic gear ring are firmly attached through the composite coupling agent.

The hard elastic toothed ring is an elastic steel toothed ring made of stainless steel.

As shown in fig. 3-5, an embodiment of the preferred elastic steel toothed ring has an inclined opening toothed ring opening 56, which has a plurality of cut-off openings 57 distributed uniformly and symmetrically along the annular continuous portion 51, and a plurality of arc-shaped long rings 52 distributed uniformly between the cut-off openings 57, wherein each arc-shaped long ring 52 points to the direction of the thick-walled pipe body and is U-shaped and radially symmetrical relative to a radial plane of the annular continuous portion 51.

Each arc-shaped long ring 52 is preferably provided with a plurality of blade teeth extending in the radial direction;

each arc-shaped long ring 52 is preferably designed with directional blade teeth 54 carved into the pipe wall or a circumferential blade tooth mouth root 53 or inclined at a certain angle relative to the radial direction; preferably the angle is inclined at 10-20 degrees to the radial direction; the angle of inclination of the blade teeth with respect to the radial direction is preferably equal to the angle of inclination of the oblique opening of the annular continuous portion 51 with respect to the radial direction.

After the elastic steel toothed ring is extruded by the periphery of the outer ring, the edge teeth 54 carved into the pipe wall are embedded into the outer wall of the thick-wall pipe 7, and an elastic sealing protection state is obtained.

The knife-edge structure is an equivalent-action knife-edge structure which can be embedded into the outer wall of the thick-wall pipe 7 under the pressure of radial contraction.

As shown in fig. 6-9, an embodiment of the preferred elastic steel toothed ring comprises an annular continuous portion 51 and a plurality of teeth uniformly arranged on the annular continuous portion 51 along its periphery, wherein each tooth is directed towards the thick-walled tubular body and is symmetrical to the radial direction with respect to a radial plane of the annular continuous portion 51;

as shown in fig. 10 to 13, in the embodiment of the present invention, the elastic steel ring gear includes an annular continuous portion 51, and the annular continuous portion 51 is a whole ring with an oblique opening; the inclined opening on the annular connecting part can be partially encapsulated to leave an encapsulation toothed ring opening 81, and the surface encapsulation can be selected to connect the openings by elastic plastic to form a closed circular ring; preferably, the two end parts of the inclined opening can be connected under the action of axial force, so that the elastic steel tooth ring forms a complete circular ring; preferably, the angled opening has only a narrow gap. The oblique opening of elastic steel ring gear can avoid because straight opening department easily causes the locking because of the clearance undersize or the too big atress inequality, ring gear warp that causes in clearance, and it is convenient that the installation before the extrusion is opened to one side moreover, and thick-walled pipe body is held tightly to adaptation operating mode that can be better in extrusion process.

One preferred embodiment includes that the seal 6 can be an O-ring seal 63 or a contoured ring seal 62;

as shown in fig. 14 and 15, the profiled ring-shaped sealing element 62 has a main body sealing ring portion and a tail portion between the main body sealing ring portion and the pipe end limiting portion 3, and the tail portion includes a self-sealing tail ring sealing element water stop ring, so that the sealing reliability is improved;

preferably, the contoured annular seal 62 is not limited to the above-described contoured configuration, but may include configurations that provide equivalent effects to enhance sealing performance.

The other preferable embodiment comprises that the extrusion bellmouth 1 is in reducing transition to the adjacent intubation bellmouth 2 and then in reducing transition to the pipe section limiting position; an inward-rolling circular ring stop is arranged at the socket part of the pipe fitting.

As shown in fig. 16 and 17, a preferred embodiment is a hard elastic toothed ring, an elastic plastic 8 coated outside the elastic toothed ring, and a toothed ring composite self-sealing rubber ring formed by integrally manufacturing a sealing member 6. This is to avoid the deformation and displacement phenomena of the sealing member 6 which often occur during the extrusion process, and to make the extrudable toothed ring and the sealing member 6 as one body, the structure and the installation process can be simplified, and a better sealing effect can be obtained. Fig. 16 shows a tooth ring composite self-sealing rubber ring with a special-shaped water stop ring, and fig. 17 shows a tooth ring composite self-sealing rubber ring with an O-shaped water stop ring.

Another preferred embodiment is a rigid elastomeric ring, the elastomeric plastic 8 covering the elastomeric ring, and the seal 6 being pre-assembled components.

While various preferred embodiments of the present invention have been described in detail, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention. It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.