Patent Application
20240110455
The present invention relates generally to Ram Blow Out Preventers (“BOPs”), and more specifically, to a forged Ram BOP internal cavity profile for lower working pressure (“LWP”) workover rigs.
The construction of BOPs for workover rigs is a process of casting. In that process of casting, metal is heated to the melting point and poured into a mold to create the BOP. However, casting components can create flaws or weak areas thereby reducing the overall strength and longevity of the BOP. Whereas, forging a BOP results in a much stronger and longer lasting BOP thereby reducing costs, time to repair or replace the BOP, and thus increasing the overall lifespan and continued operations. Forged BOPs will typically last much longer and not have the flaws of cast BOPs. They will require less maintenance.
Forged BOPs are currently used for large application operations due to the easier access internally to construct. However, forging is much more difficult in smaller BOPs and not currently used to construct workover BOPs for “snubbing” and coiled tubing in lower working pressure (LWP) BOPs. LWP is typically 3K, 5K, a range of 3K to 5K psi, or any value in this range. This is due to the complexity and difficulty of tooling and manufacturing forged smaller, lower pressure workover BOPs. Therefore, those of skill in the art will appreciate the present invention which addresses such a need.
An objective of the present invention is to provide an improved ram BOP with a forged internal cavity profile for workover rig BOPs.
Still another objective is to provide a unique and simplified design of components within the forged internal cavity that is more easily machined into a relatively small BOP.
Another objective of the present invention is to reduce maintenance and increase operational life of the BOP.
Yet another objective of the present invention is to provide an improved simple light weight reliable BOP design.
Still another objective of the present invention is to provide a design that is interchangeable with most like style BOPs for workover rigs.
Another objective of the present invention is to provide a lightweight and low-profile BOP that is ideal for workover rigs and well servicing rigs with limited height under the floor.
Yet another objective of the present invention is to provide side entry ram access on a forged BOP body for replacement of the rams.
A further objective of the present invention is to provide an internal machined profile for a BOP with a flat lower surface and a raised surface on the lower surface.
Another objective of the present invention is to provide a flat upper surface above the raised surface so that as the ram moves from the open position to the closed position, the ram seals are compressed against the flat upper surface to form a seal.
Another objective is to provide a forged BOP that can replace cast BOP units and use similar components, such as the rams.
Still another objective of the present invention is to provide mud sluts machined into the lower surface of the machined internal profile that guide fluids such as mud back into the annulus between pipe and the casing.
These and other objects and advantages may or may not be used depending on the various possible embodiment of the invention.
One general aspect includes a machined internal cavity for a forged BOP. The machined internal cavity also includes a lower surface. The cavity has a flat upper sealing surface above the lower surface. The cavity has a raised landing surface formed on the lower surface. The raised landing surface is positioned to guide the ram to engage the seal with the flat upper sealing surface when the ram is moved to a closed position.
Implementations may include one or more of the following features such as the machined internal cavity having a slot formed into the lower surface of the machined internal cavity. The slot is positioned to guide mud into the throughbore. The machined internal cavity may have a wall with an opening formed in the wall and a ram guide mounted in the opening. The lower surface may be formed so that the seal of the ram is not engaged with the flat upper sealing surface while in an open position. The ram may engage the raised landing surface during movement of the ram from the open position to the closed position such that the seal on the ram engages the flat upper sealing surface in the closed position. A side entry ram access point may be sized to allow the ram to be replaced through the side entry ram access point. The forged BOP is sized for use with a workover rig.
One general aspect includes a machined internal cavity for a forged BOP. The machined internal cavity also includes a wall for the machined internal cavity with a bore in the wall and a ram guide that is insertable into the bore. The ram may be engageable with the ram to guide the ram during opening and closing.
Implementations may include one or more of the following features including the machined internal cavity with a lower surface, a flat upper sealing surface, and a raised landing surface formed on the lower surface to guide the ram to engage the seal with the flat upper sealing surface. The raised landing surface may be positioned with respect to the flat upper sealing surface so that when the ram is moved onto the raised landing surface to a closed position, then the seal on the ram engages the flat upper sealing surface. A side entry ram access point may be sized to allow the ram to be replaced through the side entry ram access point. The raised landing surface may be positioned so that the ram is insertable through the side entry ram access point into the machined internal cavity when the ram is in an open position because the seal on the ram is not engaged with the flat upper sealing surface when the ram is in the open position. The raised landing surface may include a plurality of raised landing surfaces. The flat upper sealing surface may be flat directly above the raised landing surface. The machined internal cavity may include a slot formed in the lower surface. The slot in the lower surface may be positioned to guide mud flow into the throughbore.
One general aspect includes a machined internal cavity for a forged BOP. The machined internal cavity also includes a lower surface of the machined internal cavity and a slot machined into the lower surface. The slot in the lower surface being positioned to guide mud flow into the throughbore.
Implementations may include one or more of the following features such as a flat upper sealing surface, and a raised landing surface formed on the lower surface to guide the ram to engage the seal with the flat upper sealing surface. The raised landing surface may be positioned with respect to the flat upper sealing surface so that when the ram is moved onto the raised landing surface to a closed position, then the seal on the ram engages the flat upper sealing surface. The machined internal cavity may include a side entry ram access point sized to allow the ram to be replaced through the side entry ram access point. The raised landing surface may be positioned so that the ram is replaceable through the side entry ram access point into the machined internal cavity when the ram is in an open position because the seal on the ram is not engaged with the flat upper sealing surface when the ram is in the open position. The machined internal cavity may include an internal cavity wall within the machined internal cavity. The internal cavity wall may be opposite the side entry ram access point machined into the forged BOP. A ram guide may be installed in a counter bore machined in the internal cavity wall. The forged BOP may be sized for use with a workover rig.
These and other objectives, features, and advantages of the present invention will become apparent from the drawings, the descriptions given herein, and the appended claims. However, it will be understood that above-listed objectives and/or advantages of the invention are intended only as an aid in understanding aspects of the invention, are not intended to limit the invention in any way, and therefore do not form a comprehensive or restrictive list of objectives, and/or features, and/or advantages.
The above general description and the following detailed description and claims are merely illustrative of the generic invention. Additional modes, advantages, and particulars of this invention will be readily suggested to those skilled in the art without departing from the spirit and scope of the invention. A more complete understanding of the invention and many of the attendant advantages thereto will be readily appreciated by reference to the following detailed description when considered in conjunction with the accompanying drawings, wherein like reference numerals refer to like parts and wherein:
Detailed descriptions of the invention are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure, or manner.
Casting reduces metals to a molten form while forging shapes the metal workpiece while in a solid state.
The present forged or machined BOPs are used in workover rigs for coiled tubing or snubbing. Thus, the preferred definition is specifically a workover rig for coiled tubing or snubbing. A general definition of “workover rig” is a rig for a workover which is typically any operation done on, within, or through the wellbore after the initial completion. A more specific possible definition of a “workover rig” is a mobile self-propelled rig used to perform one or more remedial operations, such as non-limiting examples could include deepening, plugging back, pulling and resetting liners, or other operations on a producing oil or gas well to try to restore or increase the well's production. Accordingly any one, all or several of these definitions may be used individually, separately, or in some combination.
The present invention provides a lower maintenance BOP and increased operational life of the BOP as compared to a cast BOP. The forged BOP is interchangeable with most like style BOPs.
The present invention may include added safety features and certifiable lifting points based on the desired need of the operations. The BOP additionally includes API 16A elastomers for sealing.
The BOP is relatively lightweight and has a low-profile that is ideal for workover rigs and well servicing rigs with limited height under the floor.
The current design uses simplified internal structures that can be more easily manufactured by machining to form a forged BOP. The simplified internal structures perform the required functions without the complexity that some cast BOPs of this size have.
A side entry ram access is provided on the forged BOP body through which rams can be replaced.
In one possible embodiment, the ram block size is 7 1/16″ with 3000-5000 psi. Centering ears may be on the blocks to assist in moving pipes to the preventer bore to prevent damage. The temperature rating may be from 30 degrees Fahrenheit to 250 degrees Fahrenheit. Most pipes can be sheared at standard operating pressure with the current invention.
The ram BOP may be, in a preferred embodiment, a 7 1/16 inch 3000-5000 psi design suitable to provide a more cost-effective BOP that meets API requirements and is effective for small workover and well servicing rigs. The current invention provides a more cost-effective BOP. Therefore, the BOP is operable to provide the lowest rated hydraulic operating pressure required for shearing.
In one possible embodiment, an integral booster assembly may be provided to maximize shearing capacity. For example, in one embodiment, a shear ram can shear at standard operating pressure of 1500 psi for most pipe sizes. The shear blade geometry is operable to centralize tubes in the well bore. Furthermore, the rams are wire line shearing capable.
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The internal cavity 114 has a side entry ram access opening 126 where the rams may installed/replaced through the access opening 126. Furthermore, the side entry ram access point 126 allows for access to machine the internal cavity 114.
The cavity 114 extends laterally across to the inner cavity wall 122. The cavity wall 122 has a counter bore 120 in which buttons or ram guides 110 are installed to assist guiding the rams during opening and closing operations. A raised or landing surface 104 is machined or forged in the cavity 114 such that it is a higher level relative lower surface 118. The raised surface 104 is located around the bore 112 such that during closing operations the rams engage the raised surface 104 as they traverse centrally towards the bore 112 to the closed position.
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The rams are moved to the open or closed position by actuators 130 that urge the ram piston rods 128 in the desired direction. In one possible embodiment, within the ram cavity 124, counter bores or bores 120 (See
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There is a small gap between the rams 106 and upper surface 108 when the rams 106 are in the open position. As the rams 106 are moved into the closed position, the rams 106 engage raised surface 104 and are thereby moved upward to fully engage the upper surface 108 within cavity 114. The ram seals are then compressed between the upper surface 108 and the raised surface 104 creating a fluid seal.
In one possible embodiment, ram guides 110 are installed into counter bores 120 which are machined or forged into inner cavity wall 122. The ram guides 110 may assist the rams 106 in maintaining the required orientation during opening and closing.
In
As shown, lower surface 118 is flat with at least one mud slot 102 machined into the surface. In a preferred embodiment, two mud slots 102 are present. However, more than two mud slots 102 may be machined into the lower surface 118. Centrally located around the bore 112 are raised surfaces 104 machined into lower surface 118. The raised surface 104 may have a gradient, angled, sloped, curved, or the like leading from the lower surface to the raised surface such that the raised surface is higher or elevated relative lower surface 118. When the rams 106 are moved to the closed position, the rams 106 engage the raised surface 104 and are urged to engage upper surface 108. The ram seals 116 are then energized to seal off fluid movement from the bore 112. Ram guides 110 may be installed within counter bores or bores 120 which may be machined into inner cavity wall 122.
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By replacing a cast BOP Body with a forged body, the present invention avoids the many known structural problems inherent in casting, decreases maintenance needs, and extends the recertification and/or remanufacturing cycle.
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It will be appreciated that terms such as upper, lower, raised, or the like are used when the BOP is in an operating position, i.e., the BOP is vertically oriented and receives vertically oriented pipe through the throughbore in the BOP.
The foregoing disclosure and description of the invention is illustrative and explanatory thereof, and it will be appreciated by those skilled in the art, that various changes in the size, shape and materials as well as in the details of the illustrated construction or combinations of features of the various coring elements may be made without departing from the spirit of the invention. Moreover, the scope of this patent is not limited to its literal terms but instead embraces all equivalents to the claims described.
| Number | Date | Country | |
|---|---|---|---|
| 63412311 | Sep 2022 | US |
