A SEALING RING OF AN ELASTIC MATERIAL

Abstract: A sealing ring of an elastic material is adapted to be applied under expansion thereof to the spigot end of a pipe and consists of a solid main member (1), which is connected to a sealing member (5) through a thin flap (6). The main member (1) has an anchoring member (4) to receive the sealing member (5). To obtain good sealing and convenient insertion of the spigot end (8) provided with the sealing ring into a pipe socket (9) without any risk of the elastic material being overloaded, the sealing member (5) has a circular cross-section, and its connecting flap (6) to the main member (1) is so long that after mounting of the sealing ring on the spigot end (8) it extends over the outer portion (2) of the main member (1) which is disposed at the extremity of the spigot end (8).

Description: A sealing ring of an elastic material The invention relates to a sealing ring of an elastic material, consisting of a solid main member to be applied under expansion thereof to the spigot end of a pipe and a solid sealing member substantially of circular cross-section connected to said main member through ' a thin connecting flap, said sealing member, when the main member is applied, being disposed completely or partly outside the outer portion of the main member facing in the direction of the spigot end, said main member having a ring-shaped depression to receive, at least partly, the sealing member after insertion.of the spigot end into a pipe socket on an adjoining pipe. With the ever increasing demands on the reliability of seals in the joining of pipes it has been found that such sealing rings cannot always fully meet the require- ments, which chiefly concern, long-term durability and certainty of efficient sealing even under adverse conditions, such as oblique loads on the pipes. The known sealing rings of the present type also involve a risk of the main member and/or the sealing member proper being twisted during the application or during the assembling of the pipe ends. The object of the invention present is to avoid these drawbacks while providing favourable load conditions with due regard to the elastic materials used, the loading of which must not exceed given values, so that there is no risk of the material being permanently deformed, which would reduce the efficiency of the seal. This is achieved according to the invention in that the connecting flap in cross-section is of such length that after application of the sealing ring to the spigot end said connecting flap extends from the sealing member * U E O PI over the upwardly domed outer portion of the main member and to a junction between the connecting flap and the main member positioned adjacent said depression. The advantage of such an embodiment is that after insertion of the spigot end into a pipe socket of an adjoining pipe the relatively long flap will be disposed on the exterior of the upwardly domed outer portion of the main member, as, during assembling of the two pipes, the sealing member of circular cross-section will roll right up to the,said depression and be placed in position there while being flattened to some extent, to thereby provide the desired sealing pressure and secure locking. At the same time, the outer portion of the main member will be closely spaced from the inner side of the pipe socket as long as the two pipes are fitted quite correctly with respect to each other, but in case of lateral loads or obliqueness in the mutual positions of the pipes, this outer portion will engage the inner side of the pipe socket and thus serve to limit the un¬ desirable lateral mutual movements of the pipes. No lubrication is needed in the use of such a sealing ring because the friction between the parts is turned into account. To obtain a particularly efficient locking of the sealing member after the assembling of the pipes, it is expe- dient according to the invention that said depression of the main member has ' a bottom which is substantially rectilinear in cross-section and extends in parallel with the engagement face of the main member _against the spigot end. As it is important that " the sealing ring ' is fitted quite accurately on the spigot end and is secured against displacement in an axial direction during the assembling of the pipes, it is advantageous according to the invention that an engagement member is provided at the edge of the said outer portion of the main member, said engagement member being displaced radially inwardly to engage a shoulder on the spigot end and adapted to restrict the radially inward movement of the sealing member during application of the sealing ring to the • spigot end. This also makes it quite certain that the sealing member itself will be disposed at the correct point before the insertion into the pipe socket so that said rolling of the sealing member will take place exactly in the desired manner. To additionally improve the safeguard against undesirable large mutual movements of the pipes, it is expedient according to the invention that the edge portion opposite said outer portion of the main member has substantially the same radial thickness outside the said depression as said outer portion; the advantage of this is that both the said edge portion and the domed outer portion contribute to restricting lateral displacements, and at the same time the said edge portion confines the depression and thus contributes to the efficient locking of the sealing member. The invention will be described more fully below with reference to the drawing, in which fig. 1 shows a cross-section of a sealing ring according to the invention in an unaffected state, fig. 2 shows the same sealing ring applied to the spigot end of a pipe, and fig. 3 shows the sealing ring after the spigot end has been completely inserted into a pipe socket. OMPI Fig. 1 shows the cross-section of a sealing ring consisting of a main member- 1 which, at the edge which is to face ' an adjoining pipe, has an upwardly domed outer portion 2 with an engagement member 3 displaced radially inwardly. The main member 1 has a depression 4 serving to receive a sealing member 5 which is connected to the domed outer portion 2 close to the depression 4 through a flap 6 which is long in cross-section. The sealing member 5 proper has a substantially circular cross-section and may, as shown, be provided with .small serrations or another fine profiling to provide efficient friction against a socket member to be slid over the sealing ring during the assembling of two pipes. The main member 1 has an edge portion 7 which is disposed opposite said outer portion 2 and is of substantially the same height as the domed outer portion 2. The main member 1 of the sealing ring has a-slightly smaller diameter than the spigot end to which it is to be applied, and in fig. 2 the sealing ring is shown mounted on a spigot end 8. In this position, owing to the expansion of the main member 1, the sealing member 5 will assume the shown position where it engages the engagement member 3, where it is in a correct position for insertion into a pipe socket. In fig. 3 the sealing ring is shown after the spigot end 8 has been inserted into a pipe socket 9, the sealing member . 5 having been rolled into the depression 4 whose bottom is substantially parallel with the inner surface of the sealing ring, so that the sealing member will be evenly loaded. It is readily apparent from the figure that when the spigot end is formed with a shoulder 8 the engagement member 3 can contribute to preventing axial displacement of the sealing ring during insertion into the pipe socket _. . It also appears from the figure that the domed outer portion 2 as well as the edge portion 7 is of such height that their outer surfaces are quite closely spaced from the inner surface of the pipe socket 9, and one or both of them can then engage the pipe socket in case of a relative, lateral displace¬ ment of the two pipe members. The flap β engages the inner side of the pipe socket 9 and forms together with the sealing member 5 the seal proper, and with the standard dimensions * the lateral displacement which is possible in relation to the outer portion 2 and the edge portion 7 is determined so that the material in the sealing member 5 and in the flap 6 cannot be overloaded.

Claims: Patent_Claimsj: 1. A . sealing ring of an elastic material, consisting of a solid main member to be applied under expansion thereof to the spigot end of a pipe and a solid sealing member substantially of circular cross-section connected to said main member through a thin connecting flap, said sealing member, when the main member is applied, being disposed completely or partly outside the outer portion of the main member facing in the direction of the spigot end, said main member having a ring-shaped depression to receive, at least partly, the sealing member after insertion of the spigot end into a pipe socket on an adjoining pipe, c h a r a c t e r i z e d in that the connecting flap in cross-section is of such length that after application of the sealing ring to the spigot end ' said connecting flap extends from the sealing member over the upwardly domed outer portion of the main member and to a junction between the connecting flap and the main member positioned adjacent said depression. 2. A sealing ring according to claim 1, c h a r c¬ t e r i z e d in that said depression of the main member has a bottom which is substantially rectilinear in cross-section and extends in parallel with the engagement face of the main member against the spigot end. 3. A sealing ring according to claim 1, c h a a c¬ t e r i z e d by the provision of an engagement member at the edge of the said, outer portion of the main member, said engagement member being displaced radially inwardly to engage a shoulder on the spigot end and adapted to restrict the radially inward movement of the sealing member during application of the sealing ring OM WΪP to the spigot end. 4. A sealing ring according to claim 1, c h a r a c¬ t e r i z e d in that the edge portion opposite said outer portion of the main member has substantially the same radial thickness outside the said depression as said outer portion.

Inventors: CHRISTENSEN J
Applicants: CHRISTENSEN J, SCHIONNING & ARVE AS
Application year: 1981
Main classification: F16L21
IPC codes: F16L21