GB2088512A

GB2088512A - Inflatable plug for cylindrical conduits

Info

Publication number: GB2088512A
Application number: GB8133100A
Authority: GB
Original assignee: Goodyear Tire and Rubber Co
Current assignee: Goodyear Tire and Rubber Co
Priority date: 1980-11-28
Filing date: 1981-11-03
Publication date: 1982-06-09
Also published as: JPS57114087A; MX152800A; GB2088512B; CA1171004A

Abstract

A fluid inflatable plug 10 for interiorly cylindrical conduits e.g. for capping, testing for leaks or for coupling two pipes includes a rigid cylindrical mandrel 12 having an elastomeric tubular sleeve 14 about the outer curved surface 16 of the mandrel 12. The sleeve 14 includes reincorcements (15 Figure 2 not shown) which extend in opposite sense helical paths throughout the longitudinal extent of the sleeve. The sleeve 14 is folded back over one of its ends 19 to form a loop region 20 upon assembly to the mandrel 12. The ends 18,19 of the sleeve 14 are sealingly retained (e.g. by clamp rings 22) to the outer surface 16 of the mandrel 12. Means 26,27 are provided for admitting and exhausting pressurized fluid between the sleeve 14 and the outer curved surface 16 of the mandrel 12. The plug 10 may include a fluid passage 32,34 therethrough independent of means for admitting and exhausting pressurized fluid between the sleeve and the surface of the mandrel. (Figure 1) <IMAGE>

Description

SPECIFICATION Inflatable plug for interiorly cylindrical conduits The abstract is not to be taken as limiting the invention of this application and in order to understand the full nature and extent of the technical disclosure of this application reference must be made to the accompanying drawings and the follow- ing detailed description.

The present invention relates to fluid inflatable and especially air inflatable devices and particularly to a plug which may be inserted in a tubular conduit.

Expandable plugs may be used to leak test a hose or pipe, to cap offthe end of a hose or pipe, orto coupletogetherthe adjacent ends of two sections of hose or pipe.

The plug of the present invention may be better understood by reference to the following description and the drawings wherein: Figure I is a longitudinal section of an inflatable plug incorporating the invention; Figure 2 is a fragmentary section of an elastomeric sleeve utilized in a plug according to the invention.

Referring now to Figure 1 there was shown a fluid inflatable plug 10. The plug includes a rigid cylindrical mandrel 12, which in a preferred embodiment is a hollow tube 13. Tube 13 may be formed from a section of steel pipe or other suitable material. A reinforced elastomeric sleeve 14, envelops a portion of the outer curved surface 16 of the mandrel 12. The ends 18, 19, of the sleeve 14 are sealingly retained to the mandrel 12 by clamp rings 22 which force the sleeve 14 into longitudinally spaced grooves 24 which are provided on outer curved surface 16 of mandrel 12. The sleeve 14 is folded back over its end 19 to form a loop region 20. Loop region 20 permits significant radial expansion of the sleeve so that a plug according to the present invention can accommodate and sealingly engage a relatively wide internal diameter range of conduits.

Mandrel 12 further includes means for admitting and exhausting pressurized fluid between the sleeve 14 and the outer curved surface 16 of the mandrel. In the particular embodiment shown there is provided a nipple 31 in first end wall 29 of mandrel 12. There is also provided port 27 through the wall of hollow tube 13. Tube 26 interconnects nipple 31 and port 27 thereby providing a fluid passage for remote inflation and deflation of elastomeric sleeve 14.

In the embodiment shown in Figure 1, the hollow tube 13 includes walls 29 and 30 at its opposite ends.

End walls 29 and 30 may include additional orifices such as 32 illustrated in the second end wall 30 or nipples such as 34 as illustrated in first end wall 29 which in conjunction with hollow tube 13 provide a fluid passage through the plug 10 which is independent of the means provided for admitting and exhausting pressurized fluid between the sleeve 14 and the outer curved surface 16 of the hollow tube 13.

Referring now to Figure 2, there is shown the cylindrical elastomeric sleeve 14 in its asmanufactured, undeformed state. Sleeve 14 has an inside diameter 38 which is less than the outside diameter 17 of mandrel 12. The sleeve 14 is preferably formed of two plies 39 and 40 of reinforcing cords 15. The cords of first ply 39 extend in a helical path throughout the longitudinal extent of the sleeve 14. The cords of the second ply 40 of reinforcing cords 15 extend in an opposite sense helical path throughout the longitudinal extent of the sleeve 14.

The angle a at which the cords 15 of the ply 39 and 40 extend relative to the longitudinal direction of the sleeve may be varied according to the degree of radial expansibility desired for the plug. For a given fabric type and number of plies of that fabric greater burst strength and lower expansibility are obtained when the cords 15 reinforcing the sleeve 14 extend at a relatively high angle, for example, about 45 degrees relative to the lengthwise direction of the sleeve. Conversely lower burst strength but greater expansibility are obtained when the cords 15 of the elastomeric sleeve extend at a low angle, for example, about 15 degrees relative to the lengthwise direction of the sleeve.

While certain representative embodiments and details have been shown for the purpose of illustrating the invention it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit or scope of the invention.

1. A fluid inflatable plug for interiorly cylindrical conduits comprising: (a) a rigid cylindrical mandrel, (b) an elastomeric tubular sleeve about the outer curved surface of the mandrel, the sleeve including reinforcements which extend in opposite sense helical paths throughout the longitudinal extent of the sleeve, the sleeve being folded back over one of its ends to form a loop region, (c) means for sealingly retaining the ends of the sleeve to the outer curved surface of the mandrel, (d) means for admitting and exhausting pressurized fluid between the sleeve and the outer curved surface of the mandrel.

2. A plug according to Claim 1 wherein the mandrel is a hollow tube having a fluid tight cap at at least one of its ends.

3. A plug according to Claim 1 or 2 further including a fluid passage through said plug independent of the means for admitting and exhausting pressurized fluid between the sleeve and the outer curved surface of the mandrel.

4. A plug according to Claim 1 or 2 wherein the mandrel includes on its outer curved surface longitudinally spaced annular grooves, the sleeve ends being drawn down into the grooves and retained by annular clamps positioned over the grooves.

5. A plug according to Claim or 2 wherein the undeformed diameter of the sleeve is less than that of the mandrel.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Inflatable plug for interiorly cylindrical conduits The abstract is not to be taken as limiting the invention of this application and in order to understand the full nature and extent of the technical disclosure of this application reference must be made to the accompanying drawings and the follow- ing detailed description. The present invention relates to fluid inflatable and especially air inflatable devices and particularly to a plug which may be inserted in a tubular conduit. Expandable plugs may be used to leak test a hose or pipe, to cap offthe end of a hose or pipe, orto coupletogetherthe adjacent ends of two sections of hose or pipe. The plug of the present invention may be better understood by reference to the following description and the drawings wherein: Figure I is a longitudinal section of an inflatable plug incorporating the invention; Figure 2 is a fragmentary section of an elastomeric sleeve utilized in a plug according to the invention. Referring now to Figure 1 there was shown a fluid inflatable plug 10. The plug includes a rigid cylindrical mandrel 12, which in a preferred embodiment is a hollow tube 13. Tube 13 may be formed from a section of steel pipe or other suitable material. A reinforced elastomeric sleeve 14, envelops a portion of the outer curved surface 16 of the mandrel 12. The ends 18, 19, of the sleeve 14 are sealingly retained to the mandrel 12 by clamp rings 22 which force the sleeve 14 into longitudinally spaced grooves 24 which are provided on outer curved surface 16 of mandrel 12. The sleeve 14 is folded back over its end 19 to form a loop region 20. Loop region 20 permits significant radial expansion of the sleeve so that a plug according to the present invention can accommodate and sealingly engage a relatively wide internal diameter range of conduits. Mandrel 12 further includes means for admitting and exhausting pressurized fluid between the sleeve 14 and the outer curved surface 16 of the mandrel. In the particular embodiment shown there is provided a nipple 31 in first end wall 29 of mandrel 12. There is also provided port 27 through the wall of hollow tube 13. Tube 26 interconnects nipple 31 and port 27 thereby providing a fluid passage for remote inflation and deflation of elastomeric sleeve 14. In the embodiment shown in Figure 1, the hollow tube 13 includes walls 29 and 30 at its opposite ends. End walls 29 and 30 may include additional orifices such as 32 illustrated in the second end wall 30 or nipples such as 34 as illustrated in first end wall 29 which in conjunction with hollow tube 13 provide a fluid passage through the plug 10 which is independent of the means provided for admitting and exhausting pressurized fluid between the sleeve 14 and the outer curved surface 16 of the hollow tube 13. Referring now to Figure 2, there is shown the cylindrical elastomeric sleeve 14 in its asmanufactured, undeformed state. Sleeve 14 has an inside diameter 38 which is less than the outside diameter 17 of mandrel 12. The sleeve 14 is preferably formed of two plies 39 and 40 of reinforcing cords 15. The cords of first ply 39 extend in a helical path throughout the longitudinal extent of the sleeve 14. The cords of the second ply 40 of reinforcing cords 15 extend in an opposite sense helical path throughout the longitudinal extent of the sleeve 14. The angle a at which the cords 15 of the ply 39 and 40 extend relative to the longitudinal direction of the sleeve may be varied according to the degree of radial expansibility desired for the plug. For a given fabric type and number of plies of that fabric greater burst strength and lower expansibility are obtained when the cords 15 reinforcing the sleeve 14 extend at a relatively high angle, for example, about 45 degrees relative to the lengthwise direction of the sleeve. Conversely lower burst strength but greater expansibility are obtained when the cords 15 of the elastomeric sleeve extend at a low angle, for example, about 15 degrees relative to the lengthwise direction of the sleeve. While certain representative embodiments and details have been shown for the purpose of illustrating the invention it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit or scope of the invention. CLAIMS