US2249155A - Packing means for bridging plugs - Google Patents

Description

L. D. MEDDICK PACKING MEANS FOR BRIDGING PLUGS July 15, 1941.

' -Fild Dec. 11, 1939 Patented July 15, 1941 PACKING MEANS FOR BRIDGING PLUGS Lorrain D. Meddick, Los Angeles, Calif., assignor to Lane-Wells Company, corporation of Delaware Los Angeles, Calif., a

Application December 1l, 193?, Serial No. 308,601 s claims. (c1. 16e-13) My invention relates to bridging plugs, particularly to packing means for bridging plugs adapted to form a water-tight seal between the mandrel of a bridging plug and a surrounding well casing. Among the objects of my invention are:

First, to provide a packing means for bridging plugs which may, by application of a relatively small amount of force, be expanded against the surrounding casing and when so positioned has a shape inherently adapted -to seal against the transfer of fluid, either along the walls of the casing or around the mandrel of the bridging plug;

Second, to provide a bridging plug and sealing means therefor, which is particularly designed for use in conjunction with wire line or cable-operated setting tools;

Third, to provide a bridging plug of 'this character wherein material clearance may be provided between the bridging plugand surrounding casing to insure adequate circulation area and facilitate rapid movement of the bridging plug through the well bore; and

Fourth, to provide a bridging plug of this character which incorporates a novel packing element restraining means associated with the packing element so as to maintain' pressure-responsive areas at the ends of the packing element adapted to bear against the bridging plug mandrel and casing.y

With the above and other objects in view, as may appear hereinafter, reference is directed to the accompanying drawing, in which:

Figure 1 is a longitudinal sectional view of a bridging plug incorporatingr my invention:

Figure 2 is an enlarged fragmentary, detailed view showing the packing sleeve when in its packing position;

Figure 3.is a fragmentary sectional'view of the packing sleeve illustrating one end thereof and Figure 4 is an end elevational view of the packing sleeve.

The bridging plug with which my packing sleeve is incorporated comprises .a mandrel I of substantially uniform diameter and hollow, which is screwthreaded at its lower end for connection to a nose piece 2. The Vup'peside of the nose piece forms a shoulder 3 which engages a plurality of slips 4 adapted to be spread by a cone 5 slidably mounted around the mandrel I. 'Ihe cone 5 converges downwardly and a second cone 6 is mounted on the mandrel, the latter cone converging upwardly slips 'I similar to the slips 4.

A locking ring collar 8 is fitted around the mandrel .above the slips 1. The collar 8 is provided with channels which confront the mandrel I and which receive split locking rings 9 adapted to coact with wickerteeth I 0 provided on the mandrel when the parts of the bridging plug are in their sealing position. The upper end of the mandrel I is suitably constructed for attachment to a setting tool,fnot shown. 'Ihe above described elements are, in so far as my present invention is concerned, conventional, my invention having particular reference to a packing sleeve mounted between the cones 5 and 6, and the coacting ends of said cones.

The cones 5 and 6 receive therebetween a l packing sleeve II formed of rubber or -similar composition material, such as a material known commercially as Neoprene," which material may or may not contain reinforcing. 'I'he confronting ends of the cones 5 and 6 are beveled inwardly for'approximately two-thirds of their wall thickness and are beveled outwardly from their inner peripheries for approximately one-third of their wall thickness, as indicated by I2 and I3, respectively, so as to form axially directed, undercut, pointed, annularridges- I4.

The beveled face I2 of each cone may have, near its outer periphery, an axially directed, annular channel I5. l

The packing sleeve II is provided at each end with an axially directed V-shaped annular channel I6, the side walls I'I and I8 ofwhich conform to the beveled faces I2 and I3, respectively, of the cones. Inv addition, the ends of the packing sleeve are provided with annular ribs I'9 which t the channels I5 of the two cones.

'I'he channels I6 at the ends of the sleeve II form pressure lips 20 which llt in the undercut portion I3 of the cone, and pressure lips 2| which wedge between cones and the surrounding casing, as shown in Figure 2.

Operation of the packing sleeve is as follows: When the bridging plug is set the cones 5 and 6 move toward each' other, axially compressing the packing sleeve II This is accomplished by the use of a suitable setting tool (not shown) in lassociation with the brldgingplug. Axial compression of the sleeve causes radial expansion or distortion until it engages the walls of the surrounding casing designated C in Figure 2.

, Rubber or other relatively soft. yieldable material tends to ow very much like water when and coacting withk the beveled portion l2 er the subjected to pressure. Consequently, the parts of the sleeve tend to reshape themselves mate-r rially. However, the beveled portions I2 and the undercut portions I3 coacting, respectively, with the walls of the casing and the mandrel form wedge-shaped spaces into which the sleeve is crowded. Once the sleeve is in position, fluid which may tend to move between the cones 5 and 6, or the packing sleeve, encounters the pressure lips 20 and 2|, forcing them against the casing and mandrel, respectively, and preventing the passage of iiuid along the packing element.

The ribs I9 and channels I5 vcoact to restrain the ends of the packing element while lowering the bridging plug into position. When the bridging plug is in position and is set; the ribs I9v tend to shear or tear from the packer. It is immaterial, however, whether they do4 this or pull out of the channels I5, for they have no function after the packer is set.

Various changes and alternate arrangements maybe made within the scope of the appended claims, in which it is my intention to claim all novelty inherent in the invention as broadly as the prior art permits.

I claim:

1. In a bridging plug: a packing sleeve having at its ends radially outer and radially inner, ax

ially directed-pressure lips; and a packing element expander engageable with each end of said sleeve, each having an axially directed channel adapted to receive one of said pressure lips, and

a beveled face adapted to engage the other of said pressure lips.

2. In a bridging plug: a mandrel; a packing sleeve tting said mandrel adapted to be axially expanded into engagement with a surrounding casing; and expander rings engageable with the ends of the packing sleeve, said expander rings having beveled. ends forming, with the surrounding casing, substantially V-shaped channels and dening with said mandrel other substantially V-shaped channels, and said packing element provided with pressure lips at its ends adapted to be forced into conformity with said channels.

3. In a bridging plug: a mandreh. expander rings slidably mounted thereon and having confronting ends, and beveled on their radially inner peripheries; and a packing sleeve having a V- shaped channel in each end conforming to said expander rings, the walls of said channels forming inner and outer pressure lips adapted to conform to said expander rings.

LORRAIN D. MEDDICK.

Images