IL196817A - Two layer pipe junction seal - Google Patents

Description

TWO LAYER PIPE JUNCTION SEAL Pearl Cohen Zedek Latzer P-70375-IL FIELD OF INVENTION The present invention relates to non- welded pipe junctions More particularly the invention provides a seal which is dividable to suit both moderate and fully rigid pipes.

BACKGROUND OF THE INVENTION Non- welded pipe junctions are useful in situations where welding can not be carried out, or is undesirable because the pipe junction is expected to be opened either due to foreseen changes, for experimental applications or because a need is foreseen to clear blockages. Furthermore, welding can not be carried out in dangerous areas such as coal mines, on petroleum piping and in munitions factories. Further situations calling for this type of pipe joint is a do-it-yourself kit where the end user is unlikely to have welding equipment as his disposal, and where the materials of which the main and the branch pipes are made of are different, as occurs for example where the main pipe is made of steel and the branch pipes are made of a plastic.

A patent search was carried out which did not reveal any relevant prior art. However the present inventors have previously disclosed a seal profile (see FIG. 1) for this purpose which was however not dividable as is the profile of the present invention.

It has now been found that the ideal profile and particularly the thickness of the profile is different for thin or plastic pipes than for thick and metal piping. For the former more movement during clamping is required in order to reach a desired seal pressure, and this is provided for by a thick seal. However for the latter a thinner seal is preferable because the correct seal clamping pressure is reached more quickly. The seal profile which was previously disclosed by the present inventors was better suited to the thin or plastic tubes and less so for thick or metal pipes having high rigidity..

It is therefore one of the objects of the present invention to obviate the disadvantages of prior art pipe junction seals and to provide a dual-purpose seal suitable to all types of non- welded junctions.

SUMMARY OF THE INVENTION The present invention achieves the above object by providing an improved flexible seal profile particularly useful for sealing a non-welded openable pipe junction, said seal profile being dividable and used for either thin or thick pipes.

In a preferred embodiment of the present invention there is provided an improved seal profile wherein said pipe junction forms a part of a water manifold.

In another preferred embodiment of the present invention there is provided an improved seal profile having a cross-section similar to two slightly spaced-apart circles interconnected by a bridge portion having a width of about 40% - 70% of the diameter of one of said circles, each of said circles supporting an extending tapered seal lip facing away from said bridge, the improvement being the addition of a split line extending over the first of said circles and entering the second circle but stopping before reaching the edge of said second circle, said split line enabling said seal element to be used whole or to be divided in the field and to hermetically seal said openable pipe junction when under pressure from rigid clamping components.

In another preferred embodiment of the present invention there is provided an improved seal profile as wherein said split line is formed to include locating features.

In a further preferred embodiment of the present invention there is provided an improved seal profile wherein said locating features include at least one V recess on a first side of said split line and corresponding V projection(s) on the second (remaining) side of the split line.

In a further preferred embodiment of the present invention there is provided an improved seal profile wherein said locating features include at least one shallow curved recess on said first side of said split line and a corresponding curved projection on said second side.

In yet a further preferred embodiment of the present invention there is provided an improved seal profile wherein said locating features include at least one abutment recess on said first side of said split line and a corresponding abutment wall on said second side.

In another preferred embodiment of the present invention there is provided an improved seal profile wherein said seal profile is provided in ring form for use on in-line pipe couplings.

In a most preferred embodiment of the present invention there is provided an The improved seal profile as claimed in claim 1, wherein at least one of said pipes is made of a plastic material.

It will thus be realized that the novel seal of the present invention serves to seal a thin or plastic pipe junction without change of the seal structure. However where thick or metal pipes meet at a junction the seal is easily cut on site into half thickness, as the split line of the profile is easily extended using no equipment other than a sharp knife. If such knife is unavailable the seal can be parted by hand.

The locator arrangements which are called for in preferred embodiments prevent the seal from rupture when sealing forces are applied thereto. A further benefit of this shaped parting line is that even when one part of the dividable seal is used local high sealing pressure is available before the seal profile bottoms.

It can be summarized that the full thickness of the seal is used for sealing low force sealing applications while the half-thickness seal is applicable to harder less flexible sealing tasks. By "soft" the intention is to refer to pipes which are made of a thin pipe wall and/or are made of a plastic, such joints being less rigid. The word "hard" as used in the present specification refers to thick-wall pipes and/or those made of steel or other rigid material, the seal is compressed a lesser distance by surrounding components as will be seen in FIG.7.

The seal of the present invention is usually used in its ring form, as shown in FIG.8. The profile is however also suited for linier applications.

The invention will now be described further with reference to the accompanying drawings, which represent by example preferred embodiments of the invention.

Structural details are shown only as far as necessary for a fundamental understanding thereof. The described examples, together with the drawings, will make apparent to those skilled in the art how further forms of the invention may be realized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a prior art seal profile; FIG. 2a is a sectional view of a preferred embodiment of the seal profile according to the invention; FIG. 2b is a sectional view of the same embodiment as in FIG.2a, the seal being shown opened; FIG. 3 is a sectional view of an embodiment wherein the split line includes a V-shaped locator; FIG. 4 is a sectional view of an embodiment wherein the split line includes two rounded locators; FIG. 5 is a sectional view of an embodiment wherein the split line includes an abutment feature; FIG. 6 is sectional views of a "soft" junction; FIGS. 7a and 7b are sectional views of a "hard' junction; FIG. 8 is a perspective view of a preferred seal seen in disk form; and FIG. 9 is a view of a manifold built according to the present invention.

DETAILED DESCRIPTION OF PREFERRED EXEMPLARY EMBODIMENTS There is seen in FIG. 1 a prior art flexible seal profile particularly useful for sealing a non- welded openable pipe junction.

The seal profile 10 has a cross-section similar to two slightly spaced-apart circles 14, 16 which are interconnected by a bridge portion 18 having a width of about 40% - 70% of the diameter of one of the circles. Each of the circles 14, 16 supports an extending tapered seal lip 20, 22 pointing away from the bridge 18.

As seen in FIG.2a the improved profile 24 now provided according to the present invention is formed by the addition of a split line 26, extending over the first of the circles 16 and entering the second circle 14 but stopping before reaching the edge 28 of the second circle. The split line 26 enables the seal element to be used whole or to be divided in the field. The seal profile hermetically seals the openable pipe junction, shown in FIG. 6 when under pressure from adjacent outer clamping components.

The seal profile is used as is for less-rigid piping as seen in Fig. 6 and is dividable and used for rigid pipes as seen in FIGsJa and 7b..

With reference to the rest of the figures, similar reference numerals have been used to identify similar parts.

Referring now to FIGS. 3-5, there are depicted improved seal profiles wherein the split line is formed to include locating features.

In Fig. 3 seal 30 the locating features include a V recess 34 on a first side of the split line 32 and a corresponding V projection 36 on the second (remaining) side of the split line.

In Fig. 4 the seal 38 the locating features include two shallow curved recess 40, 42 on the first side of the split line and corresponding curved projections 44, 46 on the second side of said line.

In FIG. 5 the seal 48 has locating features which further include an abutment recess 50 on the first side of the split line 52 and a corresponding abutment wall 54 on the second side.

Turning now to FIG. 6, a 90° pipe junction 56 of a less-rigid type is seen, the branch pipes 58 and the main pipe 59 being made of a plastic material. The full thickness seal disk 60 is seen restricted to a space between the main pipe 59, an outer tensioning member 62 and a back-up body 64 which prevents retraction of the seal 60.

The tensioning arrangement 72 to which the outer tensioning member 62 is connected is seen in FIG. 9 but is not part of the present invention. When fully tightened the lip 20 seals against the branch pipe 58.

A rigid (hard) 90° pipe junction is seen in FIGS 7a and 7b. The seal profile 48 seen in FIG. 5 has been cut to form the seal profile 66 by extending the split line 26 a few millimeters by the use of a sharp knife. The cut-off section not used in the present embodiment can be stored for use on similar further application.

FIG.8 shows the preferred embodiment of the improved seal profile 48, seen in FIG. 5, as a circular disk seal 60.

FIG. 9 illustrates a plurality of pipe junctions 56 which together with the main pipe 59 form a water manifold 70. Any or all junctions 56 are openable, as could be required for purposes of clearing a stoppage or during the course of experimental work.

The scope of the described invention is intended to include all embodiments coming within the meaning of the following claims. The foregoing examples illustrate useful forms of the invention, but are not to be considered as limiting its scope, as those skilled in the art will readily be aware that additional variants and modifications of the invention can be formulated without departing from the meaning of the following claims.

Claims (8)

1. flexible seal profile particularly useful for sealing a non-welded openable pipe junction, said seal profile being dividable and used for either thin or thick pipes.

2. The improved seal profile as claimed in claim 1, wherein said pipe junction forms a part of a water manifold.

3. The improved seal profile as claimed in claim 1 having a cross-section similar to two slightly spaced-apart circles interconnected by a bridge portion having a width of about 40% - 70% of the diameter of one of said circles, each of said circles supporting an extending tapered seal lip facing away from said bridge, the improvement being the addition of a split line extending over the first of said circles and entering the second circle but stopping before reaching the edge of said second circle, said split line enabling said seal element to be used whole or to be divided in the field and to hermetically seal said openable pipe junction when under pressure from rigid clamping components.

4. The improved seal profile as claimed in claim 1, wherein said split line is formed to include locating features. 5. The improved seal profile as claimed in claim 4, wherein said locating features include at least one V recess on a first side of said split line and corresponding V projection(s) on the second (remaining) side of the split line. 6. The improved seal profile as claimed in claim 4, wherein said locating features include at least one shallow curved recess on said first side of said split line and a corresponding curved projection on said second side.

5. The improved seal profile as claimed in claim 4, wherein said locating features include at least one abutment recess on said first side of said split line and a corresponding abutment wall on said second side.

6. The improved seal profile as claimed in claim 4, wherein said seal profile is provided in ring form for use on in-line pipe couplings.

7. The improved seal profile as claimed in claim 1, wherein at least one of said pipes is made of a plastic material.

8. A flexible seal profile particularly useful for sealing a non- welded openable pipe junction substantially as described hereinbefore and with reference to the accompanying drawings.