DE1073255B - Electrically insulating seal - Google Patents

Description

GERMAN

The invention relates to an electrically insulating seal for socket pipes with an intermediate socket and outer wall of the male end compressed sealing ring.

Such seals are known and consist of a covering edge of the insertion end, a sealing body having an annular main part with a polygonal cross-section, which rests against the outer surface of the spigot end with a jacket-like extension.

The aim of the invention is "to improve these known seals so that their application and in particular their seat on the spigot end is improved so that the connection of the spigot end and socket end safer and the resistance of such seals is increased. This goal is achieved according to the Invention achieved in that the main part of the sealing body triangular cross-section with convex having curved outer surface and the extension of the seal body in the free state forms a frustoconical, thin-walled jacket that converges towards its free end, the inside diameter of which on the base surface corresponds to the outside diameter of the spigot end of the pipe is equivalent to.

The triangular, convex rounded shape of the end of the seal facilitates the introduction of the with the Gasket fitted spigot end in the socket end of the pipe.

The convergence of the inner and outer surfaces of the seal towards the free end enables the To overcome frictional resistance of the pipe parts better, with the jacket-like end of the Seal reduced towards its free end, so that a soft pulling of the seal on the insertion end becomes possible.

Due to the large contact area of the jacket and its light weight, directed towards its free end Convergence, an excellent fit of the seal on the spigot end is achieved, which is an absolute tight connection of the pipes guaranteed.

Since the diameter of the annular edge is equal to the outer diameter of the male end, can this does not tear the jacket of the seal at the edge. In the case of the known seals, the The outer surface of the plug-in end enclosing jacket does not converge towards its free end the risk that the seal will be torn when pulling through the pipe.

Further advantages and features of the invention emerge from the description with reference to the figures emerged. These show in

1 shows a section through an insulation seal according to the invention,

Electrically insulating seal

Applicant:

Compagnie de Pont-a-Mousson, S.A., Nancy, Meürthe-et-Moselle (France)

Representative: Dipl.-Ing. R. H. Bahr

and Dipl.-Phys. E. Betzler, patent attorneys,

Herne, Freiligrathstr. 19th

Claimed priority: France, August 30, 1956 and July 19, 1957

Jean Poirel, Nancy, Meurthe-et-Moselle (France), has been named as the inventor

2 shows a longitudinal section through an insulating seal according to the invention,

3 shows a longitudinal section through the seal placed on the insertion end of a pipe.

1 shows the seal according to the invention between the cylindrical insertion end 1 of a pipe T ₁ and the socket 2 of a pipe T ₂ . The sleeve 2 is provided with an annular seat 3, which is lengthened by a centering area 4, and an adjoining recess 5. On the seat 3 is a sealing ring made of rubber or another elastic material, which has two annular lips Qa ₁ 6 b and is clamped between the outer surface of the insertion end 1 and the centering area 4 on the one hand and the outer surface of the insertion end 1 and the inside of a cap 7 on the other is. The sealing ring can be pressed tightly on the seat 3 by means of screw bolts 8 and nuts 9 through the sleeve 7.

According to the invention, the insertion end 1 is enclosed by a sealing body B ₁ , which consists of an insulating material, for example polyethylene, and has an annular, generally triangular main part 16 with a convex outer surface 17. The main part 16 is provided on the outside as an extension of the surface 17 with a frustoconical, approximately 0.5 to 2 mm thick, conically tapering jacket 18. The conicity of the inner surface 20 (FIG. 2) in the free state is preferably about 20 to 30Vo, while the conicity of the outer surface 21 in the free state is somewhat greater and lies between 30 and 35%.

909709/260

The length L of the jacket is four times the length of the main part 16 and fifteen times the mean wall thickness of the jacket. The diameter A of the ring edge 22, the intersection of the inner surface of the jacket 18 and the base surface 23 with which the main part 16 rests against the male end 1 of the tube T ₁ , is equal to the outer diameter of the male end. The inside diameter B of the end

19 of the jacket 18 is slightly smaller than the diameter A. The length e of the base surface 23 of the main part 16 corresponds essentially to the wall thickness of the pipe.

The sealing body E _{1 is} plugged onto the insertion end of the tube T ₁ by hand while widening the free end 19 of the jacket 18. As a result of the radial pull, the jacket 18 rests elastically on the tube T ₁ (FIGS. 1 and 3).

The frustoconical design of the inner surface

20 of the jacket 18 is particularly advantageous because it allows the seal E ₁ to be pulled onto the pipe even with slightly fluctuating diameters but within the manufacturing tolerances, since it absorbs this tolerance and compensates for it through the elasticity of the polyethylene.

The large contact area of the jacket 18 gives an excellent fit of the jacket on the pipe, the is still improved by the truncated cone shape.

If the diameter A of the annular edge 22 is equal to the outer diameter of the insertion end 1 of the tube T ₁ , the jacket 18 cannot tear at the edge 22.

Due to the small wall thickness of the jacket 19 and the rounding of the outer surface 17 of the main part 16 when inserting the insertion end 1 into the socket 2, no difficulties arise.

Polyethylene is recommended as a material because of its manufacturing price and its easy ductility. This material gives the thin jacket 18 the necessary flexibility and the main part 16 the necessary rigidity so that any deformation during the insertion of the male end into the Sleeve is prevented. Furthermore, polyethylene is an excellent electrical insulator and on the in liquid present in the line without influence.

Polyethylene seals can therefore easily be installed in lines for feed water.

Of course, the invention is not limited to the embodiment shown and described, instead, numerous changes are possible.

Claims (3)

Patent claims: 1. Electrically insulating seal for socket pipes with an elastic, between the socket and outer wall of the insertion end of two pipes to be connected compressed sealing ring and a sealing ring covering the end edge of the insertion end, an annular main part with a polygonal cross-section having insulating material, which extends with a jacket-like extension the outer surface of the insertion end, characterized in that the main part (16) of the sealing body (E ₁ ) has a triangular cross-section with a convexly curved outer surface (17) and the extension of the sealing body (E ₁ ) in the free state a frustoconical, thin-walled, to its free end converging jacket (18), whose inner diameter (A) at the base surface (23) · corresponds to the outer diameter of the insertion end (1) of the tube (T ₁ ). 2. Sealing body according to claim 1, characterized in that the inner and outer surfaces (20, 21) of the jacket (18) have different conicities in the free state, the one of the inner surface (20) between 20 and 30% and that of the outer surface (21) by a small amount is more. 3. Sealing body according to claim 1 and 2, characterized in that the length of the jacket (18) is at least four times the width of the annular main part (16) and approximately fifteen times the mean jacket thickness of the sealing body (E ₁ ) . Considered publications:
German utility models No. 1 672 758, 1 678 892; U.S. Patent No. 2,653,834. 1 sheet of drawings