LU500410B1

LU500410B1 - Compression fitting

Info

Publication number: LU500410B1
Application number: LU500410A
Authority: LU
Inventors: Hemin Adelmand; Dominique Comte; Pinto Jose Teixeira
Original assignee: Aliaxis Research & Tech
Priority date: 2021-07-08
Filing date: 2021-07-08
Publication date: 2023-01-13
Also published as: EP4356036A1; WO2023281093A1

Abstract

The present invention proposes a press fitting for the connection of a pipe end and a method of crimping. The press fitting comprises a main body with a fitting portion and a fitting support extending in an axial direction from the fitting portion, and a compression sleeve mounted to the fitting portion, the compression sleeve and the fitting support defining a pipe insertion space for inserting a pipe end to be fixed on said fitting support. The compression sleeve comprises a sleeve body in a form of an open ring. The open ring has two annular ends which are connected mutually through at least one crimping ear. The crimping ear projects radially outwardly from the sleeve body. The at least one crimping ear is deformable for fixing the pipe end to the fitting, preferably by deformation against the fitting support.

Description

F27656LU Î Title: Compression fitting HUS00410 Description

[0001] Field of the invention

[0002] The present invention concerns compression fittings or press fittings. The pre- sent invention also concerns a method of assembly of such press fittings.

[0003] Compression fittings, also called press fittings, which can connect tubes by com- pression and deformation using one or two fitting sleeves, are well known in the field of tubing, piping and line system installations, for example for water, gas or heating.

[0004] Press fittings are used to connect pipes, in particular those made from plastic or composite metal-plastic. They are used to connect appropriately arranged sections of pipe, with their connecting pieces being inserted into the ends of the pipes to be connected, where they are then usually de-formed or crimped or pressed. They are fastened in certain fastening zones on the connection pieces by using so-called system compression tools that usually have interchangeable pressing jaws.

[0005] The tube, pipe, or conduit systems are assembled in several steps: first an end of the tube or pipe is inserted into a fitting, and then the fitting is crimped to guarantee good mechanical strength and a leak-tight installation. The compression is usually essentially a pressure on the fitting sleeve which causes the deformation or shaping of the fitting towards the pipe which is inserted into it. The pressure is usually applied to the fitting using a crimp- ing tool with press jaws. These pressing jaws apply pressure to the fitting material in order to bring about an interaction with the surface of the pipe(s)/tube(s) to be connected, thus achieving a reliable connection and a reliable seal. In some cases, the crimping also involves a deformation of the tube or piping itself in order to provide an interaction between the tube and an inner part of the fitting.

[0006] One object of the present invention is to provide a press fitting having improved handling capacities during installation.

F27656LU 2 LU500410

[0007] It is another object of the present invention to provide a secure connection of at least one tube or pipe, in particular part of a piping system for hot and cold-water installations inside buildings, for example as a multilayer or flexible piping system.

[0008] Summary of the invention

[0009] To this end, the present invention proposes a press fitting according to claim 1, a method according to claim 11. Preferred embodiments are defined in the dependent claims.

[00010] According to the invention, the press fitting for the connection of a pipe end, comprises a main body with a fitting portion and a fitting support extending in an axial di- rection from the fitting portion, and a compression sleeve mounted to the fitting portion, the compression sleeve and the fitting support defining a pipe insertion space for inserting a pipe end to be fixed on said fitting support. The compression sleeve comprises a sleeve body in a form of an open ring. The open ring has two annular ends which are connected mutually through at least one crimping ear. The crimping ear projects radially outwardly from the sleeve body. The at least one crimping ear is deformable for fixing the pipe end to the fitting, preferably by deformation against the fitting support.

[00011] The compression sleeve comprises a fitting body mount and the fitting portion comprises a sleeve fixation element, wherein the fitting body mount and the sleeve fixation element cooperate so that the compression sleeve is axially maintained on the fitting support and freely rotatable around said fitting support. This provides a press fitting which is pre- mounted, and the user can easily change the orientation of the compression sleeve before crimping. This is very advantageous as the installation space may be reduced or in corners not easily reachable.

[00012] In one aspect, the fitting portion is provided with a slider for holding a radial projection of the fitting body mount, preferably the slider is circumferentially extending around the fitting support, more preferably forming a ring-shaped recess with a retainer. This allows a good holding of the compression sleeve mounted to the fitting support, whilst al- lowing the rotation of the compression sleeve around said fitting support, which in turn

F27656LU 3 allows a user rotating the compression sleeve before crimping to find an easy crimping por 200410 sition even in narrow corner of roof or reach partially hiding positions.

[00013] In one aspect, the fitting body mount has at least one panoramic window to monitor the correct insertion of the pipe. This ensures that the correct connection of the tube to the press fitting for crimping, and hence of the crimping.

[00014] In one aspect, the compression sleeve comprises two crimping ears spaced apart in the axial direction. Providing two crimping ears in series provide a good mechanical re- sistance to maintain the pipe under operational condition. The number of crimping ears is not limiting the invention, and only one crimping ear, or more than two crimping ears can be provided.

[00015] In a further aspect, the compression sleeve is provided with an anti-ovalisation tongue designed to distribute the crimping force around the pipe and the main body. The anti-ovalisation tongue can be an annular projection extending from one of the annular end towards the other annular end, preferably the anti-ovalisation tongue being positioned adja- cent the at least one crimping ear and/or bridges the distance between adjacent crimping ears. The anti-ovalisation tongue limits the ovalisation of the main body during the crimping pro- cess and helps preventing the pipe flow into the crimping ears. This helps ensuring a full jointing between the pipe and the body and avoiding leakage.

[00016] The anti-ovalisation tongue can be designed to move into an anti-ovalisation channel of the sleeve body during crimping process.

[00017] The anti-ovalisation tongue and the anti-ovalisation channel form a crimping in- dicator, in particular wherein the anti-ovalisation tongue is not visible after closing of the at least one crimping ear. Again, this helps ensuring that the crimping is correctly done, and hence a reliable connection between the tube and the press fitting.

[00018] The anti-ovalisation tongue can have the same thickness as the compression sleeve. This helps guaranteeing a good repartition of force.

F27656LU 4 . . . . LU500410

[00019] The width of the anti-ovalisation tongue can vary from 0.5 to 1.5 the width of the crimping ear(s), and the anti-ovalisation tongue can have a length in the range of 0.5 to

0.75 of the length of crimping ear.

[00020] In one aspect, the press fitting is preassembled. Advantageously, the press fitting is ready for use, thereby minimizing the installation steps for the user, in particular in corners which are not easy to reach for the user

[00021] In one aspect, the compression sleeve is manufactured from a deformed metal sheet, in particular wherein the metal sheet is cut and deformed, the crimping ear(s) being formed by bending a tab around another also bent end portion of metal sheet, preferably connected using latch and hole arrangement(s). The compression sleeve, including the anti- ovalisation tongue and the fitting body mount, can be made from a single deformed metal sheet.

[00022] The pipe or tube can be mono material and made of thermoplastic materials in- cluding but not limited to PE, PB, PEX, PERT, PER ... or Composite (multi material tube structure) with different layers of functional materials (PEX, PERT, PVDF, Aluminium...).

[00023] The material for the fitting body can be metal (brass, Stainless steel.) or Ther- moplastic (PVC, PPSU, PVDF, PPS, that can also be reinforced with fibre glass reinforce- ment).

[00024] It is important to consider that the material of the fitting body must be harder than the material of the pipe surface in contact with the fitting body if a tight engagement is to be provided for radially between the pipe and the fitting body.

[00025] A full plastic press fitting can also be contemplated.

[00026] It should be noted that there is no need for pipe preparation if the fitting body does not contain an O-ring.

[00027] The present invention further proposes a method of connecting a press fitting as described above with a pipe end, comprising the steps of: inserting the pipe end into a pipe

F27656LU 5 insertion space between a fitting support and a compression sleeve; rotating the Compression 200410 sleeve around the fitting support to adjust the rotational position of the compression sleeve, and applying the crimping force on the crimping ear(s), to close the ear(s), leading to the crimping of the pipe end against the fitting support. The method has among others the ad- vantage that for easy access for the crimping tool it is sufficient to turn the undeformed compression sleeve.

[00028] In an aspect, during application of the crimping force, a/the anti-ovalisation tongue slides or moves within a/the corresponding anti-ovalisation channel in the compres- sion sleeve.

[00029] The total closing of the ear(s), and hence of the sleeve body, and/or the mutual position of the anti-ovalisation tongue and the anti-ovalisation channel, can be a visual indi- cation for a correct crimping process.

[00030] The invention also proposes the use of a press fitting such as described, wherein a crimping tool is configured to transmit the crimping pressure to the compression sleeve.

[00031] The invention also concerns a crimping process including the application of crimping pressure, by a crimping tool, on a compression sleeve of a press fitting.

[00032] Brief Description of the figures

[00033] Other characteristics and advantages of the invention will be more clearly evi- dent upon reading the description of several currently preferred embodiments, provided as examples only, with reference to the attached drawings, wherein: - Figure 1 shows a view of a press fitting according to a first aspect of the present inven- tion, - Figure 2 is an isometric view of a main body for a press fitting of Fig. 1, - Figure 3 is a front cross-sectional view of the main body of Figure 2, - Figure 4 is a front view with hidden lines of the main body of Figure 2, - Figure 5 is an isometric view of another main body for a press fitting of Fig. 1, - Figures 6 and 7 show a compression sleeve for a press fitting of Fig. 1 in one aspect of the invention,

F27656LU 6 - Figures 8 to 12 shows detail of the compression sleeve of Fig. 6 and 7 in one aspect of 200410 the invention, - Figure 13 shows a crimping process according to one aspect of the invention.

[00034] Inthe figures, identical parts are identified using the same reference numbers.

[00035] Figure 1 shows a press fitting 1 allowing the connection of a tube according to one aspect of the present invention. The tube may be for example a pipe of a piping system for hot and cold-water installations inside buildings.

[00036] In the example of Fig. 1, the press fitting allows the connection of two tube at both sides, but this is not limiting the invention. The fitting may form one side of a connector having similar or another kind of fitting on its other end or side. The fitting may also be provided at a port of a fluidic device for connecting a pipe thereto.

[00037] The mechanical fitting comprises a main body 10 for receiving a pipe end to be connected and a compression sleeve 20 provided to be crimped on the pipe end.

[00038] As can be on figures 2 to 4, the main body 10 comprises a fitting portion 12 with a fitting support 15 extending axially from the fitting portion 12. The fitting support 15 ex- tends in the axial direction X-X between said fitting portion 12 and a pipe insertion end 13.

[00039] The compression sleeve 20 is designed to surround the fitting support 15. The fitting support 15 and the compression sleeve 20 defines an insertion space 18 for the inser- tion of the pipe end to be fixed (Fig. 1).

[00040] The fitting support 15 has a plurality of radial recesses 17 extending on its outer circumference, which allow to grip the pipe. The radial recesses or grips 17 on the fitting portion 12 of the fitting support ensures good grip of the compression sleeve.

[00041] The compression sleeve 20 comprises a sleeve body 21 in a form of an open ring with two annular ends 22, 23, facing each other. The annular ends 22, 23 are connected by two crimping ears 26 projecting radially outwardly from the sleeve body 21.

F27656LU 7 LL. LU500410

[00042] The crimping ears 26 are deformed and the annular ends 22, 23 of the sleeve body move towards each other during the crimping process to close the sleeve body 21. The total closing of the ears, and hence of the sleeve body 21, is a visual indication for right crimping process.

[00043] The compression sleeve 20 is designed with two crimping ears 26 axially spaced apart. Providing two crimping ears in series provide a good mechanical resistance to main- tain the pipe under operational condition.

[00044] The compression sleeve 20 comprises a fitting body mount 56 and the fitting portion comprises a sleeve fixation element 47. The fitting body mount 57 and the sleeve fixation element 47 cooperate so that the compression sleeve 20 is axially maintained on the fitting support and freely rotatable around said fitting support 15.

[00045] Inthe example of the figures, the sleeve fixation element 47 is a circumferential slider 47 in the fitting portion 12 of the main body 10 for holding the compression sleeve.

[00046] As best seen on Figures 6 and 7, the compression sleeve 20 has two axial fitting body mounts 56 extending axially from the sleeve body 51, each axial fitting body mount 56 being provided with a radial projections 57 projecting radially from its inner surface.

[00047] The radial projections 57 act as fixing stoppers to be received in the slider 47 in the fitting portion 12 of the main body 10.

[00048] This arrangement allows holding the compression sleeve 20 in the axial position whilst providing the compression sleeve a freedom of rotational movement around said main axis, when mounted to the main body 10.

[00049] In the example of the Figures, the circumferential slider 47 is formed by a cir- cumferential groove in the fitting portion, between a first stopper 45 on the axially inner side of the fitting portion and a second stopper 46 located axially outwardly form the first stopper

45. A cover 48 extends axially outwardly from the outward radial end of the first stopper 45. The cover 48 extends above the circumferential slider 47 and the second stopper 46, and

F27656LU 8 defines an insertion space 49 for the radial projection of the compression sleeve to be clipped 200410 inside said circumferential slider 47.

[00050] The number of projections is not limiting the invention. The compression sleeve 20 may have a single circumferential projection or one or more radial projection to be fixed between two stoppers 45 on the main body 10.

[00051] Alternatively, the compression sleeve may as well be provided with a recess co- operating with a projection of the fitting portion, or any other fixation arrangement can be contemplated.

[00052] The radial projections 57 allow to fix the sleeve 20 directly on the main body without any intermediate support in a way which provide a sleeve the ability of 360° rotation around the main body. A rotational movement of sleeve is providing for a comfortable po- sition of crimping tool during the crimping process.

[00053] In addition, panoramic windows 19, extending circumferentially between the ax- ial fitting body mounts 56, are provided on the compression sleeve 20 to monitor the pipe insertion.

[00054] In addition, in the example of Figures 2 to 4, the main body 10 is a one-piece member. In another embodiment shown on figure 5, the main body 210 can be made as two parts, depending on injection requirements. In both embodiments, the main body maintains and holds the compression sleeve in the same manner, with a freedom of rotational move- ment of sleeve around said main body.

[00055] The compression sleeve 20 is provided with an anti-ovalisation tongue 60 de- signed to distribute the crimping force around the pipe and the main body, thereby limiting the ovalisation of the main body during crimping process. In addition, the anti-ovalisation tongue 60 also prevents the pipe flow into the crimping ears 60 during the crimping process. This ensures full jointing between the pipe and the body and avoid leakage.

[00056] The anti-ovalisation tongue 60 is an annular projection extending from the an- nular end 22 towards the annular end 23. The anti-ovalisation is designed to move into an anti-ovalisation channel 65 of the sleeve body 21 during crimping process.

F27656LU 9 LU500410

[00057] In the embodiment of Figures 8 to 12, the anti ovalisation tongue 60 is provided between the two crimping ears 26.

[00058] Preferably, the anti-ovalisation tongue 60 has the same thickness as the compres- sion sleeve 20. The thickness of sleeve 20 depends on the diameter of the press fitting, for example the thickness of sleeve can vary from 0.6 to 1.2 mm for mechanical fitting DN 12 to DN 32. The sleeve could be thicker for larger diameter.

[00059] The width of the anti-ovalisation tongue 60 can vary from 0.5 to 1.5 the width of the crimping ear 26. The width of the crimping ear can vary between 3 to 12 mm depend- ing on the diameter of mechanical fitting.

[00060] The length of the anti-ovalization tongue can be vary from 0.5to 0.75 length of ear. The length of ears depends on the diameter of mechanical fitting.

[00061] The compression sleeve 20 is manufactured from a deformed metal sheet. The metal sheet is cut and deformed to give the two crimping ears 26 and an anti-ovalisation tongue 60. The ears are formed by bending a tab 28 around other extreme of metal sheet via the rectangular holes 29. The channel 65 is formed to receive the anti-ovalisation tongue 60.

[00062] The compression sleeve can be manufactured by cutting, punching and cold de- forming process. However, welding or similar process can be included for mechanical fitting with large diameter.

[00063] The pipe or tube can be mono material and made of thermoplastic materials in- cluding but not limited to PE, PB, PEX, PERT, PER, PPS... or Composite (multi material tube structure) with different layers of functional materials (PEX, PERT, PVDF, Alumin- ium. ..). The material for the fitting body can be metal (brass, Stainless steel....) or Thermo- plastic (PVC, PPSU, PVDF, thermoplastic with fibre glass reinforcement).

[00064] It is important to consider that the material of the fitting body must be harder than the material of the pipe surface in contact with the fitting body.

[00065] A method for connecting a tube and a press fitting is shown on Figure 13. The method comprises the step of inserting the pipe (step S1) into the space insertion 18, and

F27656LU 10 . . . LL. LU500410 rotating the compression sleeve around the main body and the pipe inserted (step S2), and applying the crimping pressure on the crimping ears 26 until the ears are closed (step S3).

[00066] During the deformation of the crimping ears, the anti-ovalisation tongue slides in the corresponding channel.

[00067] The compression sleeve is preassembled and there is no need to reposition the compression sleeve before the crimping process. During the crimping processes, the gaps between the ears will crush and disappear. Therefore, the compression sleeve will be main- tained securely in the compressed state as the radial ends have been brought together by pinching the ear or ears. The ear/ears will avoid any inadvertent loosening as they have been deformed plastically in an irreversible manner.

[00068] It should be noted that there is no need for pipe preparation even if the fitting body does not contain an O-ring.

[00069] There is no need to pipe preparation or multi-body part assembling during in- stallations.

[00070] The press fitting 1 according to the present invention has significant impact on the crimping tool and its ergonomic. The amount of force required to crimp this technology is very low in comparison with existing mechanical fitting. , the amount of energy reduction is up to 70 %.

[00071] The sleeve can be rotated 360°, the ears aligned in series in one line, the tool does not need to surround the mechanical fitting to processed crimping process. These char- acteristics allow to reach easily difficult crimping installation position such as narrow corner of roof or reach partially hiding position.

[00072] In addition, this technology has very important impact on reducing the number of crimping tools. The dimensions of ears are relatively close for different mechanical fitting diameter, thus, only one tool can crimp wide range of mechanical fittings, for instance from DN 12 to DN 32 mm.

Claims

F27656LU 11 CLAIMS LU500410

1. Press fitting for the connection of a pipe end, comprising a main body (10) with a fitting portion (12) and a fitting support (15) extending in an axial direction from the fitting portion, a compression sleeve (20) mounted to the fitting portion (12), wherein the compression sleeve and the fitting support define a pipe insertion space for inserting a pipe end to be fixed on said fitting support, the compression sleeve (20) comprising a sleeve body (21) in a form of an open ring with two annular ends (22, 23) connected together by at least one crimping ear (26) projecting radially outwardly from the sleeve body (21), the at least one crimping ear being deformable for fixing the pipe end to the fitting, preferably by deformation against the fitting support, wherein the compression sleeve (20) comprises a fitting body mount (56) and the fitting portion comprises a sleeve fixation element (47), wherein the fitting body mount (56) and the sleeve fixation element (47) cooperate so that the compression sleeve (20) is axially maintained on the fitting support and freely rotatable around said fitting support (15).

2. Press fitting according to claim 1, wherein the fitting portion (12) is provided with a slider (47) for holding a radial projection (57) of the fitting body mount (56), preferably the slider is circumferentially extending around the fitting support, more preferably forming a ring-shaped recess with a retainer.

3. Press fitting according to claim 1 or 2, wherein the fitting body mount (56) has at least one panoramic window to monitor the correct insertion of the pipe.

4. Press fitting according to any one of claims 1 to 3, wherein the compression sleeve (20) comprises two crimping ears (26) spaced apart in the axial direction.

5. Press fitting according to any one of the preceding claims, wherein the compression sleeve (20) is provided with an anti-ovalisation tongue (60) designed to distribute the crimping force around the pipe and the main body, wherein the anti-ovalisation tongue (60) is an annular projection extending from one of the annular end (22, 23) towards the

F27656LU 12 other annular end (23, 22), preferably the anti-ovalisation tongue (60) is positioned ade 200410 jacent the at least one crimping ear and/or bridges the distance between adjacent crimp- ing ears.

6. Press fitting according to the preceding claim, wherein the anti-ovalisation tongue is designed to move into an anti-ovalisation channel (65) of the sleeve body (21) during crimping process.

7. Press fitting according to any one of claim 4 to 6, wherein at least one of the features is provided: a. the anti-ovalisation tongue has the same thickness as the compression sleeve, b. the width of the anti-ovalisation tongue can vary from 0.5 to 1.5 the width of the crimping ear(s), c. the anti-ovalisation tongue has a length in the range of 0.5 to 0.75 of the length of ear, d. the anti-ovalisation tongue and the anti-ovalisation channel form a crimping in- dicator, in particular wherein the anti-ovalisation tongue is not visible after clos- ing of the at least one crimping ear.

8. Press fitting according to any one of the preceding claims, wherein the press fitting is preassembled.

9. Press fitting according to any one of the preceding claims, wherein the compression sleeve is manufactured from a deformed metal sheet, in particular wherein the metal sheet is cut and deformed, the crimping ear(s) being formed by bending a tab around another also bent end portion of metal sheet, preferably connected using latch and hole arrangement(s).

10. Press fitting according to the preceding claim, wherein the compression sleeve, includ- ing the anti-ovalisation tongue and the fitting body mount, is made from a single de- formed metal sheet.

11. Method of connecting a press fitting according to any of claims 1 to 10 with a pipe end, comprising the steps of:

F27656LU 13 inserting the pipe end into a pipe insertion space between a fitting support and a coms 200410 pression sleeve, rotating the compression sleeve around the fitting support to adjust the rotational po- sition of the compression sleeve, and applying the crimping force on the crimping ear(s), to close the ear(s), leading to the crimping of the pipe end against the fitting support.

12. Method according to claim 11, comprising the sliding of a/the anti-ovalisation tongue within a/the corresponding anti-ovalisation channel in the compression sleeve.

13. Method according to claim 11 or 12, wherein the total closing of the ear(s), and hence of the sleeve body, and/or the mutual position of the anti-ovalisation tongue and the anti-ovalisation channel, is/are a visual indication for a correct crimping process.