1. Field of the Invention
This technology relates to oil and gas wells, and in particular to adaptors for clamping connectors in oilfield equipment.
2. Brief Description of Related Art
Conventional adapters for joining tubular wellhead components, such as API hub connectors, have two-piece clamps that are positioned to engage the flanges of the components, and are joined with bolts. The wellhead components may be, for example, a casing or wellhead, and a tubing head. Such adapters are often slow and cumbersome to install. In addition, such adapters may be unreliable, thereby allowing leakage between the flanges, and raising environmental and safety concerns. Alternative adapters have been developed to overcome the shortcomings of conventional two-piece clamps. For example, some adapters may drive dogs around the flanges to clamp the flanges together. However, many of these adapters require vendor-specific non-standard threads or other features on the components or equipment to which they are applied. This prohibits the use of such adapters with any equipment that is not specifically designed for use with that adapter. This also prevents use of the adapter to retrofit equipment originally supplied by a vendor other than the vendor of the adapter. What is needed, therefore, is an adapter that is more reliable than the conventional two-piece clamp adapter, but that can be used universally with any oil field equipment manufactured by any vendor.
Disclosed herein is an adapter for clamping flanged, or hub, ends of first and second tubular components. The adapter includes a clamp that may have two split halves, or a plurality of dog segments, with each half or dog segment having a hole extending therethrough. Each half or dog segment also includes upper and lower protrusions that define a recess therebetween, and that are spaced to accept the flanges at the ends of the first and second tubular components.
The adapter also includes a housing that surrounds at least an outer portion of the clamp. The housing is configured for removable attachment to either the first or second tubular component, or both. Such attachment may be accomplished by means of fasteners attaching the housing to the tubular component(s), or threads on the surface of the housing configured to engage threads on the surface of the tubular component(s).
A plurality of drive screws pass through the housing and engage threads in the holes of the clamp. As each drive screw rotates, it drives a half or dog segment of the clamp perpendicularly relative to the first and second tubular components. When the screw drives the clamp into engagement with the flanges, the clamp is in a locked position. Alternatively, when the screw drives the clamp away from, and out of engagement with, the flanges, the clamp is in an unlocked position.
This adapter is stronger and more robust than conventional split-type, two-piece clamps that consist only of the clamp to hold the faces of the connectors together. The adapter disclosed herein includes both an inner clamping device, and an outer housing that adds strength to the adapter assembly. This increases the ability of the adapter to withstand increased pressure and bending forces compared to conventional clamp designs.
The present technology will be better understood on reading the following detailed description of nonlimiting embodiments thereof, and on examining the accompanying drawings, in which:
The foregoing aspects, features, and advantages of the present technology will be further appreciated when considered with reference to the following description of preferred embodiments and accompanying drawings, wherein like reference numerals represent like elements. In describing the preferred embodiments of the technology illustrated in the appended drawings, specific terminology will be used for the sake of clarity. However, the technology is not intended to be limited to the specific terms used, and it is to be understood that each specific term includes equivalents that operate in a similar manner to accomplish a similar purpose.
Many oilfield operations require the connection of adjacent tubular components, such as API hub connectors. Such tubular components may typically include wellhead components, like casing heads or tubing heads. For example, as shown in
The adapter assembly includes a clamp 22 having a recess 24. The clamp 22 may be divided into separate halves, or multiple dog segments, around the circumference of the first and second tubular components 10, 14. The clamp 22 is configured to move between an unlocked position, shown in
The upper and lower protrusions 26, 28 of the clamp 22 may optionally have tapered surfaces 30, 32 configured to substantially correspond to matching tapered surfaces 34, 36 of the first and second flanges 12, 16. This allows a more even distribution of forces on the clamp 22 by the flanges 12, 16 when the clamp is in the locked position. In addition, the tapered surfaces may allow easier entry of the flanges 12, 16 into the recess 24 as the clamp 22 moves into a locked position, even when the flanges 12, 16 are not perfectly aligned with the clamp 22. Furthermore, as the tapered surfaces 30, 32 of the upper and lower protrusions 26, 28 engage the tapered surfaces 34, 36 of the first and second flanges 12, 16, the protrusions 26, 28 will tend to squeeze the flanges 12, 16 together, thereby strengthening the seal between the flanges.
In
In the embodiment shown in
The housing 40 provides a channel 42 in which the clamp 22 runs. The channel is defined by downward and upward facing flat surfaces that are perpendicular to the longitudinal axis of the first and second tubular components. When in its unlocked position, as shown in
Movement of the clamp 22 between its unlocked and locked positions is effected by drive screws 50. There may be a drive screw 50 corresponding to each clamp section or dog segment. Each drive screw 50 is configured to pass through a hole in the outer sidewall of the housing 40 and into a hole 38 in the clamp 22. Threads 52 on each drive screw 50 interact with corresponding threads on each hole 38 of the clamp 22, so that when the drive screw 50 rotates, the threads 52 drive the clamp 22 toward or away from the first and second flanges 12, 16 of the first and second tubular components 10, 14. As the threads 52 on the drive screw 50 drive the clamp 22, the drive screw 50 maintains substantially the same position relative to the housing 40, and does not travel inwardly or outwardly toward or away from the flanges 12, 16. In other words, the drive screw 50 may be fixed relative to the housing 40 in an axial direction. The drive screws 50 have a tool engagement slot 54 at an outer end thereof that can be used to turn the drive screw 50. For example, in the embodiments of
A guide bushing 56 may be provided in hole in the sidewall of the housing 40 to provide a path for, and help align, each drive screw 50 relative to the housing 40. The guide bushings 56 may be made of a high strength material, and may be bored to have a diameter with a close tolerance to the diameter of the drive screw 50 to guide the drive screw 50 through the housing 40. The guide bushing 56 may be removable to allow greater access to the drive screws 50 and the clamp 22.
Referring now to
One feature of the embodiment shown in
Also shown in
The method for locking first and second tubular components 10, 14 together using the adapter assembly 20 of the present technology includes first aligning the flanges 12, 16 of the first and second tubular components 10, 14. In addition, the adapter assembly 20 is installed on the upper tubular member 10. The adapter assembly 20 may be pre-assembled prior to installation on the first or second tubular components 10, 14. For example, the clamp 22 may be pre-attached to the housing 40 by passing the drive screws through the housing 40 and into threaded engagement with the holes 38 in the clamp sections, or dog segments. It may be desirable to turn the drive screws 50 so that the clamp 22 is fully retracted into the channel 42 of the housing 40 during installation. With the adapter assembly 20 assembled, the housing 40 may be attached to either the first or second tubular components 10, 14, or both, using the fasteners 44. Alternatively, the housing 40 may be threadedly engaged with at least one of the tubular components, as shown in
Once the adapter assembly 20 is in place relative to the first and second tubular components 10, 14, with the housing attached thereto, the drive screws 50 can be turned, by engaging a tool with the tool engagement slots 54 at the end of each drive screw 50. As the drive screws 50 turn, the threads 52 of the drive screws engage with the threaded holes 38 of the clamp sections, and the clamp 22 is driven inward toward the flanges 12, 16 of the first and second tubular components 10, 14. The clamp 22 may be driven inward until the recess 24 accepts the flanges 12, 16. In some embodiments, the tapered surfaces 30, 32 of the upper and lower protrusions 26, 28 may engage the tapered surfaces 34, 36 of the first and second flanges 12, 16. As the tapered surfaces 30, 32 of the upper and lower protrusions 26, 28 engage the tapered surfaces 34, 36 of the first and second flanges 12, 16, the first and second flanges 12, 16 are squeezed together and the seal between the flanges is strengthened. With the clamp thus positioned, the first and second flanges 12, 16 are locked, and unable to separate.
While the technology has been shown or described in only some of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention. Furthermore, it is to be understood that the above disclosed embodiments are merely illustrative of the principles and applications of the present invention. Accordingly, numerous modifications may be made to the illustrative embodiments and other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims.