FIELD OF INVENTION

This invention relates to a pipe end plug, to a pipe end plug assembly and to a method of closing off a pipe end.

SUMMARY OF INVENTION

According to a first aspect of the invention, there is provided a pipe end plug for closing off an open end of a pipe section having a conical seating face formed thereon at said open end and defining an external screw thread formation, the pipe end plug being configured for use with an end cap defining an internal cavity in which an end region of said open end of the pipe section is receivable, the end cap defining an internal screw thread and a shoulder formation defining a conical seating face, the pipe end plug comprising: an end plug body of a deformable material, having two opposed ends and defining a longitudinal axis defining between the ends, the end plug body having a first locating formation configured to be received within the open end of the pipe section and a second locating formation configured to be received within the internal cavity of the end cap, and a circumferential sealing formation which is disposed between the first and second locating formations, the sealing formation having a first conical sealing face configured to seat against the conical seating face of the end cap and a second conical sealing face configured to seat against the conical seating face of the pipe section when the end cap is screwed onto the open end of the pipe section, thereby wedging the sealing formation of the end plug body between the seating faces of the pipe section and the end cap thereby to form a barrier to fluid flow along the pipe and to form a fluid- tight seal between the pipe section and the end cap.

According to a second aspect of the invention, there is provided a pipe end plug assembly for closing off an open end of a pipe section having a conical seating face formed thereon at said open end and defining an external screw thread formation, the pipe end plug assembly comprising: the pipe end plug as described and defined hereinabove in accordance with the first aspect of the invention; and an end cap defining an internal cavity in which an end region of said open end of the pipe section is receivable, the end cap defining an internal screw thread and an internal shoulder formation defining a conical seating face configured to seat against the first conical sealing face of the end plug, the first locating formation of the end plug being receivable within the open end of the pipe section and the second locating formation of the end plug being receivable within the internal cavity of the end cap, with the circumferential sealing formation of the end plug being wedged between the seating faces of the pipe section and the end cap when the end cap is screwed onto the open end of the pipe section thereby to form a barrier to fluid flow along the pipe and to form a fluid-tight seal between the pipe section and the end cap.

The end cap may be in the form of a collar. More specifically, the collar may be in the form of a nut such as a union nut. According to a third aspect of the invention, there is provided a method of closing off an open end of a pipe section, the method including: providing an end plug comprising an end plug body of a deformable material, having two opposed ends and defining a longitudinal axis extending between the ends, the end plug body having a first locating formation at one end, a second locating formation at the other end and a circumferential sealing formation which is disposed between the first and second locating formations, the sealing formation having a first conical sealing face and a second conical sealing face; providing an end cap defining an internal cavity in which an end region of said open end of the pipe section is receivable, the end cap defining a connecting formation and an internal shoulder formation defining a conical seating face configured to seat against the first conical seating formation of the end plug body; forming a seating face at said open end of the pipe section configured to seat against the second conical sealing formation of the end plug body and forming a connecting formation on said end of the pipe section to which the end cap can be connected; and locating the first locating formation of the end plug body within the open end of the pipe section at its open end and connecting the end cap onto the open end of the pipe section so as to wedge the first and second conical sealing faces of the sealing formation of the end plug body between the seating faces of the end cap and the pipe section, respectively, thereby to form a barrier to the flow of fluid along the pipe section and a fluid-tight seal between the pipe section and the end cap.

The connecting formation of the pipe section may be in the form of an external screw thread and the connecting formation of the end cap is in the form of a complementary internal screw thread, the method including screwing the end cap into the open end of the pipe section so as to wedge the sealing formation of the end plug body between the seating faces of the pipe section and the end cap thereby to form said fluid-tight seal between the pipe section and the end cap.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features of the invention are described hereinafter by way of a non-limiting example of the invention, with reference to and as illustrated in the accompanying diagrammatic drawings. In the drawings:

Figure 1 shows an exploded sectional side view of a pipe end plug assembly in accordance with the invention and an end section of a pipe to which the pipe end plug assembly is to be fitted;

Figure 2 shows a sectional side view of the pipe end plug assembly of Figure 1 fitted to the pipe section shown in Figure 1 ; Figure 3 shows a side view of the pipe end section having the pipe end plug assembly of Figure 2 connected thereto; and

Figure 4 shows a perspective view of the pipe end plug of the pipe end plug assembly shown in Figure 1 .

DESCRIPTION OF PREFERRED EMBODIMENTS

With reference to the drawings, a pipe end plug assembly in accordance with the invention, is designated generally by the reference numeral 10. The pipe end plug assembly 10 comprises a pipe end plug 12 also in accordance with the invention and an end cap 14 in the form of a collar.

The pipe end plug assembly 10 is specifically adapted for closing off an open end of a pipe section. With reference to the drawings, an example of such a pipe section having an open end is shown as an elbow pipe section 16 having a first open end 18 and a second open end 20. An end region of the pipe section 16 adjacent the end 18 has an external screw thread 22. Furthermore, the end 18 has a conical seating face 24 formed therein. The seating face 24 has a 45° cone angle. The end cap 14 is in the form of a union nut and defines an internal cavity 26 and an internal screw thread 28 which defines the internal cavity. The internal screw thread 28 of the end cap 14 has a complementary configuration to that of the external screw thread 22 of the pipe section 16 thereby permitting the end cap to be screwed onto the pipe section. Furthermore, the end cap 14 defines an internal shoulder formation 30 defining a conical seating face 32 leading into a cylindrical bore 34. The seating face 32 has a 45° cone angle.

The end plug comprises an end plug body which has a unitary solid structure and is of a resiliently deformable plastics material such as nylon. The end plug 12 has two opposed ends 36 and 38 and defines a longitudinal axis "A" through its centre which extends between the ends 36 and 38. The end plug has a first cylindrical locating formation 40, a second cylindrical locating formation 42 and a circumferential sealing formation 44 which is disposed between the first and second locating formations. An apex of the sealing formation 44 has a larger diameter than the diameters of the locating formations 40 and 42 which have the same diameters. The sealing formation 44 thus projects outwardly beyond the circumferences of the locating formations 40 and 42. More specifically, the sealing formation 44 has a first conical sealing face 46 and a second conical sealing face 48, the conical sealing faces 46 and 48 being disposed on opposite sides of the sealing formation 44.

In use, the open end 18 of the pipe section 16 is closed off by locating the first locating formation 46 of the end plug body 12 within the open end 18 of the pipe section 16 and screwing the end cap 14 onto the open end of the pipe section so as to wedge the first and second conical sealing faces 46, 48 of the end plug body between the seating faces 24 and 32, respectively, of the end cap in the pipe section. As such, the sealing faces 46, 48 of the sealing formation 44 of the end plug body, deform so as to flatten and seat firmly against the seating faces 24 and 32 of the pipe section 16 and the end cap 14, respectively, so as to form a liquid-tight seal between the pipe section and the end cap. Being of a solid construction, the end plug forms a barrier to the flow of fluid along the pipe section 16, thereby closing off the open end of the pipe section. This invention extends to the end plug 12. The invention also extends to the method of closing off the pipe section 16 using the pipe end plug 12 and the end cap 14, as described hereinabove.

It will be appreciated that the pipe end plug 12 forms a barrier to the flow of fluid along the pipe, with the sealing formation 44 forming a fluid-tight seal between the pipe section and the end cap. The end plug 12 is thus suitable for forming a gas or liquid- tight seal between the pipe section and the end cap. It will be appreciated also that the end plug may be used with pipe sections having various different configurations. The end cap does therefore does not need to have a closed end for closing off the pipe section. This allows a relatively inexpensive and commonly available nut to be used as the end cap. The nut and the end plug are relatively inexpensive components which provide for the closing off of a pipe end in a relatively inexpensive and simple manner which providing an effective plug for sealing off the open end of the pipe end. The method of closing off the pipe section is simple to implement as the end plug can be aligned with pipe section by simply inserting the relevant locating formation in the end of the pipe section and screwing the end cap onto the pipe section.