Title of Invention	A BONNET LOCK MECHANISM FOR A BLOWOUT PREVENTER
Abstract	A bonnet lock mechanism for a blowout preventer including an angled surface disposed in the blowout preventer, a latching dog having a tapered surface disposed in the bonnet, and a lock actuator operatively coupled to the latching dog. The the lock actuator is adapted to move the latching dog such that the latching dog is in locking engagement with the angled surface of the blowout preventer.

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Quick Release Blowout Preventer Bonnet Cross-Preference to related applicatioius This application is a continuation-in-part of U.S. Patent Application Serial No. 09/849,819, filed on May 4,2001, which issued as U,S, Patent No. 6,554,247 on April 29,2003. That application is incorporated by reference in its entrety Backgrounf of lnventio Field of the Invention The invention relates generally to blowout preventers used in the. oil and gas industry. Specifically, the invention relates to a blowout preventer with a novel bonnet securing mechanism. Background Art Well control is an important aspect of oil and gas exploration. when drilling a well in, for example, oil and gas exploration applications, devices must be put in place to prevent injury to personnel and equipment associated with the drilling activities. One such well control device is known as a blowout preventer ('BOP"). Blowout preventers are generally used to seal a wellbore. For example, drilling wells in oil or gas exploration involves penetrating a variety of subsurface geologic structures, or "layers" Each layer generally comprises a specific geologic conposition such as , for example, shale, sandstone, limestone, et;, Bach layer may contain trapped fluids or gas at different formation pressures, and the formation pressures increase with increasing depth. The pressure in the wollbore typically is adjusted to at least balance the formation pressure by increasing a density of drilling mud in the wellborc or increasing pump pressure at the surface of the well. There are occasions during drilling operations when a wellbore may penetrate a layer having a formation pressure substantially higher than the pressure maintained in the wellbore. When this occurs^ the well is said to have "taken a kick." The pressure increase associated with the lack is generally produced by in influx of formation fluids (which may be a liquid, a gas, or a combination tiiereof) into the wellbore. The relatively high pressure kick tends to propagate from a point of entry in the wellbore uphole (from a high pressure region to a low pressure region). If the kick is allowed to reac* the siirface, drilling fluid, well tools, and other driling structures may be bloTMi out of the wellbore. These "blowouts" often result in cirfastrophic destruction of the drilling equipment (including, for example, itie drilling lig) and in substantial injury or death of rig personnel Because of Oie risk of blowouts, BOP's are typically installed at the surface or on the sea floor in deep water drilling arrangements so that kicks may be adequately controlled and "circulated out" of the system, BOP's may be activated to effectively seal in a wellbore until active measures can be taken to control the kick Hiere are several types of BOP's, the most common of which are annular BOP's and ram-tj'pe BOP'S. Annular BOP's typically comprise annular elastomer **packers" dint may be activated (eg., inflated) to enc^sulate driUpipe and well tools and completely seal the wellbore. A second type of the BOP is the ram-type BOP. Ram-t/pe BOP's typically conqjrise a body and at least two oppositely disposed boimets. The bonnets arc generally secured to the body about their circumference with, for example, bolts. Alternatively, bonnets may be secured to the body with a hinge aid bolts so that the bonnet may be rotated to the side for maintenance access. Interior of each bonnet is a piston actuated ram» The rams may kt either pipe rams (which, when activated, move to engage and surround driUpipe and well tools to seal the wellbore) or shear rams (which, when activated, move to engage and physically shear any drillpipe or well tools in the wellbore). The rams tyiMcally are located opposite of each other and, whether pipe rams or shear rams, the rams typically seal against each other proximate a center of the wellbore in order to completely seal the wellbore. As with any tool used in drilling oil and gas wellsj BOP's must be regularly maintained. For example, BOP's comprise high pressure seals between the bonnets and the body of the BOP. The high pressure seals in many iastances are elastomer seals. The elastomer seals must be regularly checked to ensure that the elastomer has not been cut, permanently deformed, or deteriorated by, for example, chemical reaction with the drilling fluid in the weUborc. Moreover, it is often desirable to rq>lace pipe rams witii shear rams, or vice versa, to provide diffte-ent well control options. Therefore, it is important that the blowout preventer includes bomiets that arc easily removable so that interior components, such as the rantfii and seals, may be accessed and maintained Develc^ing BOP*s that are easy to maintain is a difficult task. For example, as previously mentioned, boimets arc typically connected to the BOP body by bolts or a combination of a hinge and bolts. The bolts must be highly lorqued in order to maintain a seal between a bonnet door and the BOP body. The seal between Ihc bonnet and the BOP body is generally a face seal, and the si^al must be able to wi&fltand ttie very high pressures present in the wellbore. As a result, special tools and equipment are necessary to install m^i remove the bonnet doors and bonnets so that the interior of the BOP body may be aiscessed. The time required to install and remove the bolts comiecting the bonnet doors to the BOP body results in rig downtime, which is both expensive and inefficient. Moreover, substantially large bolts and a nearly complete "bolt circle" around the circumference of the botmet door are generally required to provide sufficient forcei to hold the bonnet door against toe body of the BOP. The size of the bolts and the bolt circle may increase a "stack height" of the BOP. It is common practice to operate a "stack" of BOPs (where several BOPs arc installed in a vertical relationship), and a minimized stack heij^t is desirable in drilling operations. Several attempts have been made to reduce stack height and the time required to access the interior of the BOP. U.S. Patent No. 5,655,745 issii^sd to Morrill shows a pressure energized seal carrier that eliminates the face seal be^veen the boimct door and tiie BOP body. The BOP shown in the '745 patent enables the use of fewer, smaller bolts in less than a complete boh circle for securing tiie bonnet to the body. Moreover, the '745 paiesit shows that a hinge may be used in place of at least some of the bolts. U.S. Patent No. 5,897,094 issued to Brugman et al discloses an improved BOP door connection that includes upper and lower coimector bars for securing bonnets to the BOP, The improved BOP door connection of the *094 patent does not use bolts to secure the bonnets to the BOP and discloses a design that seeks to minimize a stack height of the BOP, Summary of Inventioii In one embodiment, the invention relates to a bonnet lock mecbanism for a blowout preventer includes a radial lock, a radial lock d^lacemait device, and at least one lock actuator opcratively coupled to the radial lock displacemem: device. The radial lock is comprised of straight section* and the radial lock disjilacement device is adapted to radially displace tiie radial lock to form a locking enijagement between a bonnet and a body of the blowout preventer. In another embodiment^ the invention relates to a boimet loci; mechanism for a blowout preventer includmg an angled surface disposed in the blowout preventer, a latching dog having a tapered surfece disposed in the bonnet, mid a lock actuator operativcly coupled to the latching dog. The &e lock actuator is adapted to move the latching dog such that tiie latohing dog is in locking engaganeit with the angled surface of the blowout preventer. Brief Description of Drawings Figure 1 shows a partial section and exploded view of a BOP comprising an embodiment of tiie invention. Figure 2 shows an enlarged view of a portion of tiie embodiment shown in Figure 1. Figure 3 shows an embodiment of a radial lock displacement device. Figure 4 shows anoflier embodiment of a radial lock displacement device. Figure 5 shows an embodiment of the invention whore a radiiil lock is pinned to a portion of a bonnet. Figure 6 shows an embodiment of a radial lock conqmsing two halves. Figure 7 shows an embodiment of a radial lock comprising four scgpnients. Figure 8 shows an embodiment of a radial lock comprising a plurality of segments. Figure 9 shows an embodiment of a notched serpentine radial lock. F^iure 10 shows an embodiment of a locking mechanism used in an embodiment of the invention. Figure 11 shows an embodiment of a locking mechanism used ii an embodiment of the invention. Figure 12 shows an embodiment of a locking mechanism used in an embodiment of the invention. Figure 13 shows an embodiment of a high pressure seal used in an embodiment of tlie invaition. Figure 14 shows an embodiment of a high pressure seal used in an ^anbodiment of the invention. Figure 15 shows an embodiment of a high pressure seal used in an embodiment of the invention. Figure 16 shows an embodiment of a high pressure seal used in an embodiment of the invention. Figure 17 shows an embodiment of a high pressure seal used in im embodiment of the invention. Figure 18 shows an embodiment of flie invention wherein a radiiil look is disposed in a recess in a side passage of a BOP body. Figure 19 shows an embodiment of a radial lock comprising two Ixalves. Figure 20 shows an enibodiment of a radial lock comprising four segments. Figure 21 shows an embodiment of a radial lock comprising a plundity of kerfs. Figure 22 shows an embodiment of a radial lock comprising gradxisited kerfs. Figure 23 shows a side perspective view of an embodiment of a swivel sUde mount used in an end)odiment of the invention. Figure 24 shows a front perspective view of an embodiment of a swivel slide mount used in an embodiment of the invention. Figure 25 shows a top perspective view of an embodiment of t. swivel sUde mount used in an embodiment of the invention. Figure 26 shows a perspective view of one embodiment of a bonnet latching mechanism. Figure 27A shows a cross-section of an mibodiment of a bonnet latching mechanism in an unlatched position. Figure 27B shown a cross-section of an embodiment of a bonnet latching mechanism in a latched position. Figure 28A shows a cross-section of an embodiment of a coupling between a latching dog and a shaft. Figure 28B shows a cross-section of another embodiment of a coupling between a latching dog and a shaft. Figure 29 shows a perspective view of an embodiment of a bonr.et door. Figure 30A shows a cross-section of an embodiment of a bonnet latching mechanism in an unlatched position. Figure SOB shown a cross-section of an embodiment of a bonn Figure 31 shows a cross-section of an embodiment of a bonnet latching mechanism in an unlatched position. Figure 32 shown a cross-section of an embodiment of a bonnet 1 itching mechanism in a latched position. Figure 33 A shows a front view of an embodiment of a bonnet latching mechanism. Figure 33B shows atop view of an embodiment of a stick-in dog. Figure 33C shows a cross-section of an embodiment of a stick-in dog in a latched position. Figure 34A shows a cross-section of an embodiment of a bonnet latching mechanism in an unlatched position. Figure 34B shown a cross-section of an embodiment of a bonnet latching mechanism in a latched position. Figure 35A shows a cross-section of an embodimmt of a bonnet Latching mechanism in an xmlatched position. Figure 35B shown a cross-section of an embodiment of a bonnet latching mechanism in a latched position. Figure 36A shows a side view of an embodiment of a bonnet latchhig mechanism in a latched position. Figure 36B shows a top view of an embodiment of a bonnrt latching mcchamsm in a latched position. Figure 36C shows a top view of an embodiment of a bonnet latohing mechanism in a latched position. Figure 37A shows a cross-section of an embodiment of a bonnst latching mechanism in an unlatched position. Figure 37B shown a cross-section of an embodiment of a bound: latching mechanism in a latched position. Detailed Description An embodiment of the invention is shown in Figure 1. A ram-t}i»e blowout preventer (BOP) 10 comprises a BOP body 12 and oppositely disposed bonnet assemblies 14. Ttc BOP body 12 fiirther comprises couplings 16 (which niEiy be^ for example, flanges) on an upper surface and a lower surface of the BOP bod> 12 for coupling the BOP 10 to, another BOP or to a well tool. The BOP body 12 i^)mprises an internal bore 18 therethrough for the passage of drilling fluids, drillpipt., well tools, and the like used to drill, for exan^le, an oil or gas well. The BOP body 12 furth^ comprises a plurality of side passages 20 wherein each of the plurality of side passages 20 is generally adapted to be coupled to a bonnet assembly 14. The bonnet assemblies 14 are coupled to the BOP body 12, typically in opposing pairs as shown in Figure 1. Each bonnet assembly 14 further com^>rises a plurality of components ad^ted to seal the bonnet assembly 14 to tiie BOP body 12 and to activate a ram piston 22 within each bonnet assembly 14. Components of the boimet assembhes 14 comprise passages theredirough for movement of the ram piston 22. Each bonnet assembly 14 generally comprises similar components. While each bonnet assembly 14 is a separate and distinct part of the BOP 10, the operation and structure of each bonnet assembly 14 is similar. Accordingly, in crder to sin^lify the description of the operation of the BOP 10 and of the bonnet tissemblies 14, the components and operation of one bonnet assembly 14 will be described in detail. It should be understood that each bonnet assembly 14 operates in a s:tmilar manner and that, for example, opposing bonnet assemblies 14 typically operate in a coordinated manner. Proceeding with the description of the operation of one bonnet assembly 14, the piston 22 is adapted to be coupled to a ram (not shown) that may be, for example, a pipe ram or a shear ram. Each ram piston 22 is coupled to a ram actuator cylinder 24 that is adapted to displace flic ram piston 22 axially within the bonnet assembly 14 in a direction generally perpendicular to an axis of the BOP body 12, the axis of the BOP body 12 being generally defined as a vertical axis of the intertal bore 18 (which is generally parallel with respect to a wellbore axis). A ram (not shown) is generally coupled to the ram piston 22, and, if the rams (not shown) are shear rams, the axial displacement of the ram piston 22 generally moves the ram {not shown) into the internal bore 18 and into contact with a corresponding ram (not shown) coupled to a ram piston 22 in a bonnet assembly 14 disposed on an opposite side; of the BOP 10. Alternatively, if the rams (not shown) arc pipe rams, axial displacement of the ram piston generally moves the ram (not shown) into the internal bors 18 and into contact with a corresponding ram (not shown) and with drillpipe and/or well tools present in the wellbore. Therefore, activation of the ram actuator cylinder 24 displaces the rain piston 22 and moves the ram (not shown) into a position to blo:k a flow of drilling and/or formation fluid through the internal bore 18 of the BOP body 12 and, in doing so, to form a high pressure seal that prevents fluid flow from passing into or out of the wellbore (not shown). The ram actuator cylinder 24 further comprises an actuator 26 which may be, for example, a hydraulic actuator. However, other types of actuators are known in the art and may be used with the invention. Note that for purposes of tie description of the invention, a "fluid" may be defined as a gas, a liquid, or a combination thereof If the ram (not shown) is a pipe ram, activation of the ram piston 22 moves the ram (not shown) into position to seal around drillpipe (not shown) or well tools (not shown) passing through the internal bore 18 in the BOP body 12. further, if the ram (not shown) is a shear ram, activation of the ram piston 22 moves the ram (not shown) into position to shear any drillpipe (not shown) or well tools (not shown) passing through the internal bore 18 of the BOP body 12 and, therefore, 8;eal the internal bore 18, Radial Lock Mechanism for Coupling Bonnets to BOPs An important aspect of a BOP 10 is the mechanism by which the bonnet assemblies 14 arc sealed to the body 12. Figure 1 shows a radial lock ricchanism 28 that is designed to provide a high pressure locking mechanism that retEiins a high pressure radial seal between the bonnet assembly 14 and the BOP bod)' 12. Moreover' the radial lock mechanism 28 is designed to simplify maintenance of the bonnet assembly 14 and the rams (not shown) positioned therein. In the embodiments shown in the Figures, the side passages 20 and other components of the BOP 10 designed to be engaged therewith and therein are shown as being 6vai or substantially elliptical in shape. An oval or substantially elliptical shape (e.g., an oval cross-section) helps reduce the stack height of the BOP, thereby minimizing weight, material used, and cost. Other shapes such as circular shaes, however, are also suitable for use with the invention. Accordingly, the scope of the invention should not be limited to the shapes of the embodiments shown in the Figures. The radial lock mechanism 28 is positioned within the bonnet assembly 14 and within the side passage 20 of the BOP body 12. In this embodimant, the radial lock mechanism 28 comprises a bonnet seal 29 disposed on a bonnet body 30, a radial lock 32, a radial lock displacement device 34, a bonnet door 36, and lock actuators 38. The bonnet seal 29 cooperatively seals the bonnet body 30 to the BOP body 12 proximate the side passage 20. The bonnet seal 29 comprises a high pressure sea! that prevents fluids in the internal bore 18 of the BOP body 12 from escaping via the side passage 20. Various embodiments of the bonnet seal 29 will be discussed in detail below. When the bonnet seal 29 is formed between the bonnet body 30 and the BOP body 12. the bonnet body 30 is in an installed position and is located proximate the BOP body 12 and at least partially within the side passage 20. Because the bonnet seal 29 is a high pressure seal, the radial lock mechanism 28 must be robust and able to withstand very high pressures present in the internal bore 18. The embodiment shown in Figure 1 comprises a novel mecharism for locking the bonnet assembly 14 (and, as a result, the bonnet seal 29) in place. Referring to Figure 2, the radial lock 32 has an inner diameter adapted to fit over an exterior surface 40 of the bonnet body 30 and slide into a position adjacent a sealing end of the bonnet body 30. The radial lock 32 shown in Figure 2 comprises two halves separated by a center cut 46. However, the radial lock 32 may comprise additional segments and the two segment embodiment shown in Figure 2 is not intended to limit the scope of the invention. Additional embodiments of the radial lock 32 will be described in greater detail below. The radial lock displacement device 34 also has an inner diamets' adapted to fit over the exterior surface 40 of the bonnet body 30. Moreover, the radial lock displacement device 34 further comprises a wedge surface 48 on an extenal diameter that is adapted to fit inside an inner diameter 50 of the radial lock 32. The radial lock displacement device 34 also comprises an inner face 56 that is adopted to contact an outer surface 54 of the BOP body 12. In an installed position, the bonnet body 30, the radial lock 32, and the radial lock displacement device 34 are positioned between the BOP body 12 and the bonnet door 36. An inner surface 52 of the bonnet door 36 is adapted to contact the outer surface 54 of the BOP body 12. Note that the engagement between the bonnet door 36 and the BOP body 12 is not fixed (e.Hy the bonnet door 36 is not bolted to the BOP body 12). Referring again to Figure 1, the bonnet assembly 14 is adapted to slidably engage at least one rod 70 through a swivel slide mount 74 (note that two rods 70 are shown slidably engaged, through the swivel slide mounts 74, with each bonnet assembly 14 in Figure 1). As a result of the slidable engagement, the bonne; assembly 14 may slide along the rods 70. As will be discussed below, the slidable enigagement permits the bonnet assembly 14 to be moved into and out of looking and sealmg engagement with the BOP body 12. The lock actuators 38 are coupled to the bonnet door 36 whh either a fixed or removable coupling comprising bolts, adhesive, welds, flirefxiled comxections^ or similar means known in the art. Ihe lock actuators 38 are also ciooperalively coupled to the radial lock displacement device 34 in a similax fashiai. Additionally, the couphng between the lock actuators 38 and the radial lock displacement device 34 may be a simple contact engagement. Note that the embodiments in Figure 1 shows two lock actuators 38 coi^led to each bonnet door 36. Ho^vever, a single lock actuator cylinder 38 or a plurality of lock actuators 38 may be ustjcl with the invention. The lock actuators 38 shown are generally hydraulic cylmders; :iowe\'er, other types of lock actuators (including, for exaixlple, pneumatic actuators, electrically powered motois, and the like) are known in the art and may be used with tbi; invention. Moreover, the lock actuators 38 may be manually operated. Tie lock actuators 38 shown in the present embodiment typically are controlled by, for example, an external electrical signal, a flow of pressurized hydraulic fluid, etc. As an alternative, the radial lock 32 may be activated by manual means, such as, for '^xample^ a lever, a system of levers, a threaded actuation device, or otiier similar me^ms known in the art. Further, it for example, the lock actuators 38 comprise hydiaulic cylinders, the hydraulic cylind^^ may be activated by a manual pun^s. i^x^cordingly, maniial activation of the radial lock 32 is within the scope of the invention. A fully assembled view of the bonnet assembly 14 including the radial lock mechanism 28 is shown in Figure 2. During operation of the raclial lock mechanism 28, the bonnet assembly 14 is first moved into position proximate Ihe BOP body 12 by sliding the bonnet assembly 14 toward the BOP body 12 on the rods 70. The lock actuators 38 are then activated so that they axially dispkce C^herein an axis of displacement corresponds to an axis of the side passage 20) the radial lock displacement device 34 in a direction toward the BOP body 12. As the radial lock displacement device 34 moves axially toward the BOP body 12, thei wedge surface 48 contacts the inner diameter 50 of the radial look 32, thereby movnig die radial lock 32 in a radially outward direction (eg., toward an inner radial lock iJiirface 58 of the side passage 20). When the activation of the radial lock mechanisxa 28 is complete, an inner nose 60 of the radial lock displacement device 34 is proxiaiate a load shoulder 44 of the bonnet body 30, and an outer perimeter 62 of the radia. lock 32 is lockingly engaged with tiie inner radial lock surfece 58. Moreover, as will be described below, both the radial lock 32 and the inner radial lock surface 58 typically comprise angled surfaces (refer to, for example, the engagement sur&ces described in the discussion of Figures 10 and 11 infra). When the radial lock 32 engages the inner radial lock surface 58, the angled surfaces are designed to provide an axial i'orce that ^pulls' the bonnet door 36 in an axially inward direction and fmnly against the exterior of the BOP body 12 and thereby completes tiie locking engagemeni of the radial lock mechanism 28. When the radial lock 32 is secured in place by the activation of the lock actuators 38 and the radial lock displacement device 34, the bonnet body :fO and the bonnet assembly 14 are axially locked in place with respect to the BOP body 12 without !he use of, for example, bolts. However, an additional manual locking mechanism (not sho^n) may also be used in combination with the invention to ensure that the radial lock 32 remains securely in place. Once Ihe radial lock 32 is secuied in place by, for example, hydraulic actuation, a manual lock (not shown), such as a pinned or threaded mechanism, may be activated as an additional restraint The secured radial locking mechanism 28 is designed to hold the bonnet assembly 14 and, a The radial lock mechanism 28 may be disengaged by reversing tlies activation of the lock actuators 38 (e.g., after the pressure in die internal bore 18 has been relieved). As a result, the invention comprises a radial lock mechanism 28 that includes a positive disengagement system {e.g., the lock actuators 38 must be iWtivatcd in order to disengage the radial lock mechanism 28). The wedge surface 48 used to radially displace the radial lock M may comprise any one of several wnbodiments. Referring to Figure 3, in one embodiment, the wedge surface 48 of the radial lock displacement device 34 may compiise a smgle actuation step 80. hi ano&cr embodiment shown in Figure 4, the wedge surface 48 may comprise a dual actuation step 82. Note that the single actuation step (80 in Figure 3) gmerally has a shorter actuation stroke than the dual actuation step (82 in Figure 4). FurtheTp an actuation step angle (84 in Figures 3 and 4) is designed to maximize a radial actuation force and minimize a linear actuation force. In one embodiment of die invention, the actuation step angle (84 in Figures 3 and 4) is approximately 45 degrees. In another embodiment of the invention, the actuation step angle (84 in Figures 3 and 4) is less than 45 degrees. In ano&er embodiment shown in Figure 5, the radial lock disjilacement device 34 lurtfaer comprises a slot 90 and at least one retention pin 92 designed to retain the radial lock 32 against the load shoulder 44 of ±e bonnet body 30. In this embodiment, the radial lock 32 is retained in place by the at least one retention pin 92, and the bonnet body 30 and the radial lock 32 are held in a fixed I'elationship after the radial lock 32 has been actuated and is in locking engagement wiih the inner radial lock surface (58 in Figure 2) of the side passage (20 in Figure 1). The radial lock (32 in Figure 1) may also coroprise any one of sc^v'cral embodiments. The radial lock 32 shown in the embodiment of Figure 1 conaprises two radial minored halves 94, 96, as iurther shown in Figure 6. In anotlMsr embodiment, as shown in Figure 7, a radial lock 100 may be formed, from at least two substantially Unear segments 102 and at least two semicircular end segments 104. In another embodiment, as shown in Figure 8, a radial lock 106 may be fomicjd from a plurality of substantially straight dogs 108 and a pluraUty of curved dogs 110. The embodiments shown in Figures 7 and 8 essentially comprise radial locks 100, 106 similar to the radial lock (32 in Figures 1 and 6) of the first embodiment but divided into a plurality of segments. The radial locks 100,106 could be manufactured by, for exan:5)le, manufacturing a solid radial lock and sequentially saw cutting the solid radial lock into two or more segments. However, otiier manufacjturing techniques arc known in the art and may be used to manufacture the radial lock. In another embodiment shown in Figure 9, a radial lock 112 may be formed from a notched seqpentine structure 114 similar to a "serpentine belt." Hie radial lock 112 is formed, for example, as a single solid piece and then cut 117 through an inner perimeter 114 or an outer perimeter 116. The cuts 117 can either con5)letely transect die radial lock 112 or may include only partial cuts. Further, if tilie cuts 117 transect the radial lock 112, the individual segmmts can be attached to a flexible band 118 so that the radial lock 112 can be actuated with an actuating ring (34 in Figure 1). The flexible band 118 may comprise a material with a relatively low elastic modulxis (when compared to, for example, the elastic modulus of the indhndual segments) so that the flexible band 118 can radially expand in response to the radial displacement produced by the radial lock displacement device (34 in Figure 1). Radial expansion of the flexible band 118 results in a locking engagement between thi) radial lock 112 and the inner radial lock surface (58 in Figure 2) of the BOP body (12 in Figure 1). The engagement between the radial lock (32 in Figure 1) and the inner radial lock surface (S8 in Figure 2) may also comprise diflfcrent. embodiments. In one embodiment, as shown in Figure 10, a radial lock 120 may com|»ise a single profile engagement inchiding a single radial lock engagement sur&ce 12.2, The single radial lock engagement surface 122 is designed to lockingly engage a BOP engagement surface (59 in Figure 2) formed on the inner radial lock surface (58 in Figure 2) of the side passage (20 in Figure 1). In another embodiment, as shown in Figure 11, a radial lock VM can:q>rises a dual profile engagement including two radial lock engagement surfaces 126. Moreover, the radial lock 124 may also comprise a plurality of radial lock engag^nent surfaces designed to lockingly engage a corresponding number of BOP engagement surfaces (59 in Figure 2) formed on the inner radial lock surface (58 in Figure 2) of tlic side passage (20 in Figure 1) of the BOP body (12 in Figure 1). The radial locks described in the referenced embodiments axe designed so that the cross-sectional area of engagement between the radial lock engagement surfaces with the BOP engagement surfaces (59 in Figure 2) is maximized- Miiximizing the cross-sectional areas of engagement ensures that the radial locks positvely lock the bormet assembly (14 in Figure 1) aad, as a result, the bonnet seal (29 ki Figure 1) in place gainst the hi^ pressures presoat in the internal bore (18 in Figure 1) of tiie BOP (10 in Figure 1). Moreover, as discussed previously, angles of the engagement surfaces may be designed to produce an axial force that firmly pulls the bonnet door (36 in Figure 1) against the BOP body (12 in Figure 1) and that in sonis! embodiments may assist in the activation of the bonnet seal (29 in Figure 1). The radial locks and the engagement surfaces described in the foregoing embodiments may be coated with, for sample, hardfacing materials and/or friction reducing materials. The coatings may he^ prevent, for example, galling, Another embodiment of the lock ring is shown at 127 in Figure 12. The radial lock 127 comprises a plurality of saw cuts 128, a plurality of holes 12S', or a combination thereof. The saw cuts 128 and/or holes 129 decrease the weight md area moment of inertia of the radial lock 127, thereby reducing the actuation force required to radially displace the radial lock 127. In order to pmnit some elastic deformation of tine radial lock 127, the radial lock 127 may be formed from a material having a relatively bw modulus of elasticity (when compared to, for example, steel). Such materials comprise titanium, beryllium copper, etc. Moreover, modifications to the radial lock 127 geometry, in addition to those referenced above, may be made to, for example, further reduce the area moment of inertia of the radial lock IIT and reduce bending stresses. Tlie radial locks described above are designed to operate below mx elastic limit of the materials fix)m which they are fonned. Operation betow the elastic limit ensures that the radial locks will not permanently deform and, as a result of ttie permanent deformation, lose effectiveness. Accordingly, material selection and cross-sectional area of engagement of the engagement surfaces is very importaol to the design of the radial lock mechanism (28 in Figure 1). Referring to Figure 1, the bonnet seal 29 is designed to withstand the high pressures preset in the internal bore 18 of Ae BOP body 12 and to thisrcby prevent fluids and/or gases from passing from the internal bore 18 to the exterior of the BOP 10. The bonnet seal 29 may comprise several different configuraticris as shown in the following discussion of Figures 13-17. Moreover, the seals discloiiKjd in the discussion below may be fomied from a variety of materials. For example, the seals may be elastomer seals or non*elastonier seals (such as» for example, metal seals, PEEK seals, etc). Metal seals may further comprise metal-to-metal C-ring seals and/or mctal-to-metal lip seals. Further, the sealing arrangements shown below may include a combination of seal types and materials. Accordingly, the type of seal, number of seals, and the material used to form radial and face seals are not intended to limit the bonnet seal 29. The embodiment in Figure 13 comprises a bonnet seal 130 ibrmcd on a radial perimeter 132 of a bonnet body 133. The radial seal 130 further comprises two o-rings 134 disposed in grooves 136 formed on the radial perimeta-132 of the bonnet body 133. The o-rings 134 sealingly engage an inner sealing perimeter 138 of the side passage (20 in Figure 1) in the BOP body 12. The embodiment sthown in Figure 13 comprises two grooves 136, but a single groove or a plurality of grooves may be suitable for use with the o-rings 134. Moreover, while the cmbodiaient shows two o-rings 134, a single o-ring or more than two o-rings may be used in tiie invention. In another embodiment shown in Figure 14, a bonnet seal 140 comprises at least two packing seals 146 (which may be, for example, t-seals, lip seahi, or seals sold under the trademark PolyPak, which is a mark of Parker Hannifin, Inc.) disposed in grooves 148 formed on a radial perimeter 142 of a bonnet body 144, The packing seals 146 sealingly engage an inner sealing perimrter ISO of the side passajje (20 in Figure 1) of the BOP body 12. The embodiment shown in Figure 14 coraprii5 In another embodiment shown in Figure 15, the bonnet seal 152 comprises a radial seal 154 disposed in a groove 166 formed on a radial perimeter 1 (iO of a bonnet body 162. Moreover^ the embodiment comprises a face seal 156 dispoEsed in a groove 164 formed on a mating face siurface 168 of the bonnet body 162. Iliie radial seal 154 is adq>ted to sealingly engage an inner sealing perimeter 158 of the: side passage (20 in Figure 1) of the BOP body 12. The face seal 156 is adapted to iiealingly engage an exterior face 170 of the BOP body 12. The radial seal 154 and fa In another embodiment shown in Figure 16, the bomiet seal 17J1 comprises a radial seal 174 disposed in a groove 178 formed on a seal carrier 180. Tins seal carrier 180 is disposed in a groove 182 formed in a bonnet body 184 and also comprises a face seal 176 disposed in a groove 177 formed on the seal carrier 180. llie face seal 176 is adapted to sealingly engage mating face surface 186 of the BO? body 12, and the radial seal is adapted to sealingly engage an inner sealing perimeter 188 formed on the bonnet body 184. The bonnet seal 172 may also comprise an energizing mechanism 190 that is adapted to displace the seal carrier 180 in a direction toward the exterior surface 186 of the BOP body 12 so as to energize the face seal 176. The energizing mechanism 190 may comprise, for example, a spring, a thrust washer, or a similar structure. The energizing mechanism 190 helps ensure that the fece seal VIS maintains positive contact with and, thus, maintains a high pressure seal with the ejitmor surface 186 of tiie BOP body 12. However, the energizing mechanism 190 is not required in all embodiments. For exan:q)le, the seal carrier 180 may be designed so that both the radial seal 174 and the face seal 176 arc pressure activated without the assistance of an energizing mechanism 190. In the embodiment without an energizing mechanism, a diameter and an axial thickness of a seal carrier (such as the seal carrier 180 shown in Figure 16) are selected so that high pressure from the internal bore fibrst moves tih.e seal carrier toward the exterior surface of the BOP body. Once the face seal sc^elingly engages the exterior surface, the high pressure from the internal bore causes the seal carrier to radially expand until the radial seal sealingly engages the groove ii the seal carrier. A similar design is disclosed in U.S. Patent No. 5,255,890 issued to IVtorrill and assigned to the assignee of the present invention. Tbe *890 patent clearly describes the geometry required for such a seal carrier. In the embodiment shown in Figure 16, the face seal 176 and the radial seal 174 may be, for example, o-rings, packing seals, or any other high pressure seal known in the art Moreover, Figure 16 only shows single seals disposed in single grooves. However, more than one seal, more than one groove, or a combination thereof may be used with the invention. In another embodiment shown in Figure 17, the seal carrier 192; as shown in die previous embodiment is used in combination with a backup seal 194 disposed in a groove 196 on an external surface 198 of a bonnet body 200. Hie backup seal 194 may be an o-ring, a packing seal, a metal seal, or any other high pressure seal known in the art The backup seal 194 further maintains a high pressure seal if, for example, &ere is leakage from the seals disposed on the seal earner ivi. iNoie max me embodiment shown in Figure 17 does not include an energizing mechanism. Advantageously, some of tiie seal embodiments reduce an axial force necessary to form the bonnet seal. The bormct seals shown above greatly reduce the sensitivity of the bonnet seal to door flex by maintaining a constant squeeze njjrardless of wellbore pressure. The radial seal anangements also reduce the total area ipon which wellbore pressure acts and thus reduces a separation force that acts to push tiie bonnet door away from the BOP body. In another embodimeat of the radial lock shown in Figure 18, the radial lock mechanism 220 comprises a radial lock 222 disposed in a recess 224 formed on an internal surface 226 of a side passage 228 'of a BOP body 230. The operation of the radial lock mechanism 220 differs from the embodiments desca:ibed above in that securing a bonnet body 232 and, accordingly, a bonnet door (not isliown) and a bonnet assembly (not shown), in place is accomplished by actuating the radial lock mechanism 220 in radially inward direction. The structure of the embodiment shown in Figure IS is similar tc> the structure of the embodiments described above except for the direction of actuation of the radial lock mechanism 220. Therefore^ the discussion of the present embodiment will include a description of how the alternative radial lock mechanism 220 dijffers &om those shown above. Common elements of the embodiments (such as» for exan^le, the bonnet door 36> the linear rods 70, etc) will not be described again in detail Moreover, it should be noted that the embodiment of Figure 18 clocs not reqxiire, for example, actuator cylinders or a radial lock displacement device (e.g^^ the embodiment of Figure 18 does not require an internal actuation mechanism). Actuation of Ae radial lock 222 is in a radially inward directior.. Accordingly, the radial lock 222 must be coupled to an actuation mechanism th^t differs &om, for example, the radial lock displacement device (34 in Figure 1) and the lock actuators (38 in Figure 1) described in the previous embodiments. In one embodiment of the invention, the radial lock 222 conpises a structure similar to thoise shown in Figures 6 and 7, As shown in Figure 19, separate halves 236, 238 of the radial lock 222 ma-y be coupled to radially positioned actuators 240. When the bomiet body 232 is moved into a sealing engagement with the BOP body 230, the actuators 240 are activated to displace the halves 236, 238 of the radial lock 222 in a radiall)' inward direction so that the radial lock 222 engages a groove (244 in Figure 18) fcntned on an exterior surface (246 in Figure 18) of the bonnet body (232 in Figure Al). The radial lock mechanism (220 in Figure 18) locks the bomxct body (232 in Figure 18) and, therefore, the bonnet door (not shown) and the bonnet assembly (not shown) ha place and eaergizes the high pressure seal (234 in Figure 18). Note tliat the high pressure seal (234 in Figure 18) may be formed from any of the embodunents shown above (such as the embodiments described witih respect to Figures 13-] 7). Moreover, the radial lock 222 and the groove 244 may comprise angled surfsxies (as disclosed in previous embodiments) that produce an axial force that pulls tiie bonnet body 232 (and the bomieC assembly (not shown) and bonnet door (not shovai)) toward the BOF body 230 and further ensure a positive locking engagement. Moreov^, as shown in Figure 20, the radial lock 222 may com;prise more than two parts. If a radial lock 250 conqprises, for example, four parts 25:2, 254, 256, 258^ an equal nimiber of actuators 240 (e.g., four) may be used to actuate ihe radial lock 250. Alternatively, fierwer actuators 240 (e.g.^ less dian four in the enil)odim6nt shown in Figure 20) may be used if an actuator 240 is, for example, coupkd to more than one part parts 252, 254, 256, 258 of the radial lock 250. The aciiiators 240 may be hydrauHc actuators or any other type of actuator known in the art. Moreover, the actuators 240 may be disposed within the BOP body (230 in Fiijure 18) or may be positioned external to the BOP body (230 in Figure 18). The actuators 240 may be coupled to the radial lock 250 with, for example, mechanical or hydraulic linkages (not shown). On another embodiment, the radial lock 222 conqwises a plurality of dies or dogs (not shown) that are coupled to and activated by a pliirality of actuators (not shown). In another embodiment of tiie invention shown in Figure 21, a ralial lock 270 may be formed &om a single segment 272. The radial lock 270 is actuatt^i by circumferential actuators 274 coupled to the radial lock 270 and disposed proxiir ate ends 276, 278 of the segment 272. When activated, ttie circumfCTcntial actuators 274 move the ends 276, 278 of the segment 272 towards each otho: and in a radially inward direction as shown by the arrows in Figure 21. The dashed line in Figure 21 represente an inner surface 277 of the radial lock 270 after actuation. The radial lock ;i70, when actuated, engages the bonnet body (232 in Figure 18) in a maimer similar to that shown in Figure 18. The segmttit 272 of the radial lock 270 may be produced by fornaing a plurality of kerfs 284 proximate the end segments 280, 282. The kerfs 284 may be designed to ease installation of Ibe radial lock 270 in ttie recess (224 in Figure^ 18) and to improve flexibility for radial deformation of the radial lock 270. The kerfs may be of any shape known in the art. For example, Figure 22 shows recbmgular kerfs 284. However, the ker& 284 may preftxably be formed in a mannei that reduces stress concentrations or stress risers at the edges of the kcrfc 284. For «j>:ample, if the kerfs 284 are formed as rectangular shapes, stress risers may fonn at the relatively sharp comers. Accordingly, the kerfs 284 may comprise filleted comers (not shown) or, for example, substantially trapezoidal shapes (not shown) to minimize the effects of stress risers. Moreover, the kerfs 284 may be "graduated," as shown in FigujtJ 22, to produce a substantially smooth transition between relatively stiff straight segments 286 and relatively flexible end segments 280, 282. Graduation of the losrfs 284 effects a smooth stifGaess transition that helps prevent stress risers at the \\^t kerf (e.g., at the last kerf proximate the straight segments 286). The radial lock 270 may be formed from a single material or fion:. different materials (conq)rising, for exanq)le, steel, titanium, beryllium copper, or ojmbinations and'or alloys thereof). For example, the curved end segments 280, 282 may be formed from a material tiiat is relatively compliant when compared to a relatively rigid material forming the straight segments 286 (e.g,, the curved and segments 280, 282 may be formed from a material with an elastic moduhis (Ec) that is substaitially lower than an elastic modulus (Es) of the straight segments 286). Regardless of tlie materials used to form the radial lock 270, the radial lock 270 must be flexibk ^ough to permit installation into and removal from the recess (224 in Figure 18). Alternatively, the radial lock 270 of Figure 21 may coniprise moire than one segment {e.g,, two halves or a plurality of segments) coupled to and actuaUsd by a plurality of circumferential actuators. The radial lode 270 may also com:[>rise a plurality of separate dies or dogs coupled by a flexible band. The dies may b>3 separated by gaps, and the distance of separation may be selected to provide a desins The dies and the flexible banding may comprise different materials. For example, tfac dies may be formed from a substantially stiff material (e.g,y a material with a relatively high modulus of elasticity) comprising, for example, si'^iel or nickel based alloys. The flexible banding, in contrast, may be formed from materials having a relatively lower modulus elasticity and comprising, for example, titanium alloys or pultruded flats or shapes comprising fiberglass, carbon fibers, or ;> The embodiments shown in Figures 19-22 may be advantageous b«3 Swivel Slide Mount for Bonnet Assemblies Referring again to Figure 1, another in^rtant aspect of the in-vcintion is the swivel slide mounts 74 cooperatively attached to tibe rods 70 and to C/ach of the bonnet assemblies 14. As described previously herein, the bonnet assemblies 14 are coupled to the swivel slide mounts 74, and the swivel slide mounts 74 iu« slidably engaged with the rods 70. The swivel slide mounts 74 are adapted Ic allow the bonnet assemblies 14 to rotate proximate their axial centerlines so that tlic rams (not shovin) and the interior components of both the bonnet assemblies 14 au d the BOP body 12 may be accessed for maintenance, to change the rams, etc. An embodiment of the swivel slide mount 74 is shown in Figui'cs 23 and 24. The swivel slide mount 74 comprises a swivel slide mountmg bar 76 aiid a swivel plate 78. The swivel slide mounting bar 76 is slidably attached to the ro»ivel slide mounting bar 76 and is cooperatively attached to an ^^er surface 75 of the ]:)onnet assembly 14, The cooperative attachment of the swivel slide mount 74 to the bcrinet assembly 14 is made substantially at an axial centerline of the bonnet assembly 14. The rods 70 are designed to be of sufficient length to permit the bcrinet assembly 14 to disengage from the BOP body 12 and slide away from the BOP body 12 until the ram (not shown) is completely outside the side passage 20. Moreover, a point of attachment 82 where the swivel slide mount 74 is coopwatively attached to the upper surface 75 of the bonnet assembly 14 may be optimized so that the jsoint of attachment 82 is substantially near a center of mass of the bonnet assembly 14. Positioning the point of attachment 82 substantially near the center of mass reduce^, the force required to lotate the bonnet assembly 14 and also reduces the bending iitress experienced by the swivel plate 78. The swivel plate 78 may fiarther include a bearing 85. For exaaiple, the bearing 85 may be cooperatively attached to the swivel slide mounting b^r 76 and adapted to withstand both radial and thrust loads generated by the rot action of the bomiet assembly 14. The bearing 85 may comprise, for example, n combination radial bearing and thrust bearing (such as, for example, a t^er^ roUer bearing). Alternatively, the bearing 85 may con^rise, for example, a roll(3' bearing to support radial loads and a timist washer to support axial loads. Hov^ever, other types of bearing arrangements are known in the art and may be used with tlus swivel plate 78. When the ram (not shown) is completely out of the side passage 20, the borniet assembly 14 can rotate about a rotational axis of tiie swivel plate 78 so that the ram (not shown) and the side passage 20 may be accessed for maintenance, inspection, and lie like. In the embodiment shown in Figures 23 and 24, the lo^^er bonnet assembly 14 is shown to be rotated approximately 90 degrees with respect to the BOP body 12 while the upper bonnet assembly 14 remains in locking engagctnent with the BOP body 12. A ram block attachment point 80 is clearly visible. Figure 25 shows a top view of the BOP 10 wh«i one of the bonnet assemblies 14 has been disengaged from the BOP body 12 and rotated approxima3:ely 90 degrees. As shown, the ram block attachment point 80 is clearly visible audi may be vertically accessed. Vertical access is a significant advantage because prior art bonnets that include hinges generally pivot about an edge of tiie bonnet door. Therefore, if, for example, a lower BOP bonnet was unbolted and pivoted open, tbe ram could not be vertically accessed because the body of the upper BOP bonnet was in the way. Vertical access to the ram is inq)ortant because it makes it much ? The bonnet assembly 14 may also be rotated qjproximately 90 degrees in the other direction with respect to an axis of the side passage (20 in Figure 1), thereby permitting approximately 180 degrees of rotation. However, oiier embodiment may be designed that permit rotation of greater than or less than 180 degrees. The range of rotation of the swivel slide mount 74 is not intended to limit the scope of the invention. The swivel slide mount 74 is advantageous because of the simplicity of the design and attachment to the bonnet assembly 14. For exan?)le, prior art hinges are generally complex, difficult to manufacture, and relatively expensive. Further, prior art hinges have to be robust because they carry the full weight of the BOP bonnet about a vertical axis positioned some distance away &om the center of mass of the bonnet. The bending moment exerted on the hinge is, as a result, very bi{;tL and deformation of the hinge can lead to "sagging" of the bonnet. Other Mechanisms for Coupling Bonnets to ^OPs Figures 26-37B show othen embodiments of latching mechanisms for latching a bonnet to BOP body. The embodiments described are only provided as examples of latching mechanisms that can be used in accordance with the invctition. The invention is not limited by any one mechanism. Figure 26 shows a cutaway of one embodiment of a latch mechanism 610. A BOP body 602 and a bonnet 604 are held securely together by latch nnschanism 610. The mechanism 610 includes a radial lock 612> 614 and a radial lock displacement device 616, 618, similar to those described above. The radial lock, bi this embodiment, comprises only straight sections 612, 614. A first straight ixjction 612 extends horizontally and a second straight section 614 extends vertically. It is understood that in some embodiments two additional straight sections, one horizoiilal and one vertical, may be positioned on sides of the bonnet 604 that arc not shown in the cutaway of Figure 26. The radial lock displacement also comprises a horizontal section 616 and a vertical section 618 that radially displace the horizontal and v^cal sections 612» 614 of the radial loclc It is understood that in some embodiments another horizontal and another vertical section (not shown) may be used on the sides of the boruiet 604 not shown in Figure 26. In the embodiment shown in Figure 26, the radial lock has no curved (or radial) sections. Only straight sections 612, 614 are displaced into locldng engagement with a corresponding radial lock sur&ce (not shown) of the BOP body 602. In at least one embodiment, each of the straight sections coc^rises a plurality of smaller sections. Another embodiment of a latching mechanism is shown in Figuru 27A, A bonnet 704 is securely coupled to a BOP body 702 by a latching dog 7i;i disposed inside the bonnet 704. The latching dog 712 includes a tiered edge 714 tliat lockingly engages with an angled surface 706 of the BOP body 702 to lock the boniurt 704 with the BOP body 702, even under the high pressure experienced during a blowout. The angle of the tapered edge 714 may be selected so that the extmsion of the latching dog 712 will pull the bomiet 704 axially towards the BOP body 702 an into the proper coupled position, in &e event it is not in that position when the Litchiug mechanism is engaged. In some embodiments, the taper angle may be a "'locktig taper." A locking taper is a taper having an angle selected such that the latching clog 714 will not be forced toward a retracted position by pressure that tends to force- the bonnet 704 and the BOP body 702 away from each other. In some embodiments, a locking taper has an angle between 3 degrees and 10 degrees. In at least one embodiment, a locking taper is about 6 degrees. Those having ordinary skill in the art; will realize that a locking ts^er may be varied, depending on the particular ^plication. In this embodimait, the latching dog 712 is coupled to a shaft 7:16 and a piston 718. The actuator may be driven by hydraulic fluid, a pneumatic fliid, a motor, or any other actuation means that is know in the art. Those having skill ia the art will be able devise other methods for actuating the latching dog 712. In somes embodiments, such as the one shown in Figures 27A and 27B, a spring 719 is included to provide iipwaid force that will tend to push the latching dog 712 into locking engagement with the angled surface 706 of Ac BOP body 702, As shown in Figui'cs 27A and 27B, the shaft 716 may be sealed with seals 720 so that hydraulic fluJcls caimot esc£^e the inside of the bonnet 704 during operation of the latching mechanism. The embodiment shown in Figures 27A and 27B has a latching dog 712 positioned in the bonnet 704 and able to extend into engagement with the BOP body 702. ITiose having ordinary skill in tbe art will realize tiiat the latching dogs may also be disposed in a BOP body such that the latching dogs would extend into lodaing engagement witti an angled surface of the bonnet. Furtfaefa all of the embodiments described below include a latching mechanism with elements that engage to cc The latching dog 712 may be coupled to the shaft 716 by any means known in the art. For example, the shaft 716 may be coupled to the latching dog 712 by a threaded connection. Such a connection would enable the latching dog 712 to be moved in the upward and downward directions. Figure 28A shows another embodiment of a connection between a latching dog 732 and a shaft 736. The shaft 736 includes a generally dovctail-sh^ed protrusion 739 at Its upper end. The dovetail-shaped protrusion 739 is fit into a dovetail-shaped recess 738 in the latching dog 732. The cooperation of the dovetail-striped protrusion 739 with the dovetail-shaped recess 738 enables the latching dog 732 to be moved botii upwardly and downwardly, and it enables the latching dog 732 to "float" so that it may fit better wifli the tapered edge (706 in Figures 27A and 27B) of the BOP body(702 in Figures 27A and 27B). Figure 28B shows anotiier embodiment of a floating coupling betvreen a latching dog 742 and a shaft 746. The latdiing dog 742 includes a groove 748, and the shaft 746 includes a tongue 749. The engagement of the tongue 749 and the groove 748 creates a "tongue-in-groove" connection between the latchii^ dog 7421 and the shaft 746. Those having ordinary skill in the ait will be able to devise other couplings between a sbait and a latching dog, without departing from the scope of the ]>:resent invention-Figure 29 shows an embodiment of a bonnet door 900 that may be used with one or more of the latching mechanisms disclosed herein. The bomiet door 900 has a front face 902 that feces towards the centerhne (not shown) of the BOP body (not shown) when the bonnet is coupled to the BOP body (not shown). A hole 904 in die bonnet door 900 enables the ram actuator (not shown) to pass through tho bonnet door 900. The bonnet door 900 has a groove 912 along the length of its top side. The groove 912 provides a location in which latching mechanisms may be positioned. A similar groove 914 extends along the bottom side of the boxmet door 900. A channel 922 extends through the bonnet door 900 proximate the groove 912 in tiic top side. The channel 922 enables hydraulic or pneumatic fluids to be pumped into the bonnet door 900 to energize the latching mechanisms (not shown) positioned in the groove 912. Also, mechanical devices may be inserted and moved in the channel 922 to enable the movement of latching mechanisms (not shown) in the groove 912. A similar chaimel 924 is located proximate the lower groove 914. Figures 30A arul 30B show one embodiment of a mechanical de\ice that may be used to move latching dogs 1012, 1014, positioned inside a bonnet KKM, mto engagement wiih a BOP body 1002. A movable actuator 1006 moves insid«: the bonnet 1004 to move the latching dogs 1012, 1014 into the engaged position. It is noted that in different embodiments the movable actuator 1006 may move in different ways. For example, in one embodiment, the movable actuator slides. It is dso expressly within the scope of this invention to have an actuator on rollers. Those 'laving ordinary skill in the art will be able to devise other ways to facilitate the movcmeit of an actuator. Figure 30A shows the latching dogs 1012, 1014 in an unengaged position. The latching dogs 1012, 1014 are located in recessed surfaces 1020, 1921 ^at enable the latching dogs 1012, 1014 to be positioned within the bonnet 1004. The movable actuator 1006 also includes a plurality of support surfaces 1032, 1034. Inclined surfaces 1022» 1023 are positioned between the recessed surfactssi 1020,1021 and the support surfaces 1032,1034. As the movable actuator 1006 miy/es (eg., to the right in Figure 30A), the latching dogs 1012, 1014, which are held in place in the boimet 1004, are pushed upward into recesses 1024,1025 in the BOF boiy 1002. Figure 30B shows the latching dogs 1012,1014 in an engaged f x>sition. The latching dogs 1012,1014 have been pushed partially into the BOP body 1002 by Ihe movable actuator 1006. The dogs lpl2, 1014 are supported on support surfaces 1032, 1034, and the latching dogs 1012, 1014 extend into recesses 1024, 1025 in the BOP body 1002 to form a locking engagement. The bonnet 1004 may be icnlatched by moving the movable actuator 1006 back to its initial position, as shown in Figure 30A. Figure 31 shows another embodiment of a latching mecbandsm according to the invention. A latx^hing dog 1112 in a bonnet 1104 is connected to a recess track 1132 in a movable actuator 1134 by a pin 1114. As an actuator 1134 moves the rail 1132, the latching dog 1112 is moved upward into a locking engagement with a recess 1120 in the BOP body 1102. By moving the rail 1132 in the opposite direction, the latching dog 1112 returns to the unlatched position. It is noted that tht lecess track 1132 and tbe actuator 1134 may form one piece, or they may be formed of sieparate components that are coupled together. Figure 32 shows another embodiment of a latching mechanism lor coupling a bonnet 1204 to a BOP body 1202 according to the invention. A latching dog 1212 is coupled to a siQ>port dog 1214 by two angled bars 1215,1216. Each angid bar 1215,1216 IB htngedly connected to both the latching dog 1212 and Ihe support dog 1214. The support dog 1214 is coupled to two linear actuators 1232, 1234 that move the support dog 1214 back and forth. A recess 1222 in the bonr et 1204 enables the siq>port dog 1214 to move side to side, but not up and down. Tlic latching dog 1212 may move up and down, but not side to side. Whwi the supporl: dog 1214 is moved (e.g., to the right in Figure 32)» the angled bars 1215,1216 push the latching dog 1212 upward and into a bcking engagement with a recess 1220 in the BOP body 1202. In some embodiments, the support dog 1214 is moved by only ono actuator. Further, in at least one embodiment, the support dog 1214 in moved by maaual actuation. Those having skill in the art will be able to devise other methods of actuating the support dog 1214 without departing from the scope of the invention. Another embodiment of a latching mechanism is shown in Figures 33A-33C. Figure 33A shows an elevation view of the front face of a bonnet di)or 1306 of a bonnet 1304, The bonnet door 1306 includes four stick-in dogs 1312, 1314, 1316, 1318. While four stick in dogs are shown 1312, 1314, 1316, 1318, the invention is not limited to four. Any number of stick-in dogs may be used without departing from the scope of the invention. Figure 33B shows a close-up of a stick-in dog 1312. The stick-in dog 1312 includes three latching members 1332, 1334, 1336 atteched circumfereiitially around a shaft 1330. As shown in Figure 33C, latching member 1332 is attachi^l to the shaft (shown in dashed lines at 1330) at a distance from the bonnet door 1306. As the bonnet 1304 is coupled to a BOP body 1302, the stick-in dogs (1312, 1314, 1316,1318 in Figure 33A) mate with the BOP body 1302 in slots (1346, for example, is shown in Figure 33C) that are shaped like the stick-in dogs. For each stick-in dog (1312, for exan^le), a portion of the shaH 1330 and the three latchmg members 1332, 1334, 1336 are inserted into the BOP body 1302. The stick-in dog 1312 is then rotated so that tapered surfaces on the latching members (1332, 1334, 1336 to Figure 33B) engage with the angled surfaces interior of the BOP bod;^. For example, in Figure 33C, latching member 1332 has a tapered surface 1344 tiiiat ^gages with an angled surface 1347 in the BOP body 1302. Because of ttic mgle of the tapered surface 1344 and tiie angle of the angled surface 1347, the b*)nnet 1304 is pulled towards the BOP body 1302 as the stick-in dogs are rotated. The Ijonnet 1304 and the BOP body 1302 may be uncoupled by rotating the stick-in doi;s 1312, 1314, 1316, 1318 in the opposite direction. Figures 34A and 34B show another latching mechanism in accordance with the invention, A bonnet 1404 includes semi-dovetail protrusions 1406. 1407, 1408 each having one tigered surface (shown generally at 1414). The BOP body 1402 has similar semi-dovetail protrusions 1416, 1417 with opposing t^icsred surfaces (shown generally at 1412), The semi-dovetail protrusions (1406,1407,1408, and 1416,1417) are spaced so that the protrusions on the bomiet 1406,1407,140 3 may be inserted into the BOP body 1402 and past the protrusions on the BOP body 1416, 1417, as shown in Figure 34A By doing so, the protrusions on the BOP body 1416, 1417 will be extend into &e bonnet 1404 as well The tiered surfaces 1414 in lie bonnet 1404 are opposed tc the tiered suifeces 1412 in the BOP body 1402 in such a way that wh«i the protrusictns 1416,1417 in ttie BOP body 1402 moves relative to the bonnet 1404 (e,g., to the loit in Figures 34A and 34B), they lockingly engage the bonnet protrusions 1406, 1407, as shown in Figure 34B. As the tapered surfaces 1412, 1414 are pressed against each other, the BOP body 1402 and the bonnet 1404 are pulled together. It is not(5d that either of ttie bonnet 1404 and the BOP body 1402 could provide moving siirfeces, allowing ±t other components to remain stationary. Figures 35A and 3SB show anoth^ embodiment of a lat;^lliing mechanism in accordance with the invention. In Figure 3SA a latching member 1512 is coupled to Ae BOP body 1502 by a support member 1536. The latching naembcr 1512 is also coupled to a linear actuator 1532 by a rod 1534. The latching member 1512 includes a tapered suriiace 1514 (y]>posed to a tapered surface 1524 of the bonnet 1504, when the bonnet is positioned in a side opening of Ac BOP body (not shown). To latch the bonnet 1504 to the ElOP body 1502, the latching member 1512 is moved closer to the BOP body ISfti so that the tapered surface 1514 on the latching member 1512 contacts the tiered surface 1524 on the bonnet 1504, as shown in Figure 35B. Tlie latching member 1512 is moved by the actuator 1532, and it slides along ihc support member 1536, ITie contact pressure between the tapered surfaces 1514, 1524 pulls the bonnet 1504 closer to the BOP body 1502. The invention in not limitcd to a linear actuator, For example, in some embodiments, the latching member 1512 is moved by manual actuation. Those having ordinary skill in the art will be able to devise other activation methods that do not depart from the scope of the invention. Figures 36A-36C show another embodiment of a latching mechanism at accordance with the invention. Figure 36A shows a side view of a bonnet ;l(S04 and a BOP body 1602 that are coupled together. The bonnet 1604 includes a plurality of latching extensions (e.g., latching extension 1612 in Figure 36A) that extend along the side of the BOP body 1602. The BOP body 1602 includes latching dogs (e.g., BOP latching dog 1622) that extend away from the BOP body 1602. The BOP latching dogs (e.;g BOP latching dog 1622) are staggered with the bonnet latching extensions (e.g., 1612) so that they pass each other when the bonnet 1604 and the BOP body 1602 are coupled. A latching bar 1632 would then pass m between the dogs (e.g., bonnet dog 1612 and BOP dog 1622) to lock the bonnet 1602 in place. Figure 36B shows a top view of the latching bar 1632 positioned between the bonnet latching dog 1612 and the BOP latching dog 1622. Any foroes that would tend to separate the bonnet 1604 and the BOP body 1602 would be absorbed in sheer by the latching bar 1632. Figure 36C shows a top view of an embodiment of a latching mechanism. A latching bar 1632 is hingedly coupled to the BOP body by a swing member 1633 and a hinge 1634. The latching bar 1632 may be pivoted into a position between the bonnet latching dogs (e,g,, latching dog 1612) and the BOP latching dcgs (e.g., latching dog 1622). In this position, the latching bar may resist any fores that would tend to uncouple the bonnet 1604 and the BOP body 1602. Figures 37A and 37B show another embodiment of a latching member according to the invention. Figure 37A shows a pivot member 1714 in an unlatched position. The pivot member is connected to the BOP body 1702 by a hinge 1715 so that the pivot member 1714 may pivot. A linear actuator 1716 is coupled to the pivot member 1714 by a actuation member 1717. The bonnet 1704 includes a latching dog 1712, about which the pivot member may 1714 latch. Figure 37B shows the pivot member 1714 in a latched position. A latching surface 1732 of the pivot member 1714 latches around the latching do{; 1712 to resist forces that tend to separate the BOP body 17W and the bonnet 1704. The latching surface may be tapered to ease the latching process. In some embcoclimeats, the latching surface 1732 forms a locking taper. In some embodiments, such as the one shown in Figure 37A, the BOP body 1702 includes a mechanical stop. A screw 1722 is maintained in place by a stop 1724. The position of the screw 1722 may be adjusted so that the pivot member 1714 may be unlatched when desired. When latched, the screw 1722 may be positioned so that the pivot member 1714 may not move out of latching contact with the latching dog 1712 on the bonnet 1704, Other actuation devices may be used without departing frorn the scope of the invention. For example, the pivot member 1714 may be pivoted by manual activation. The method of actuation is not intended to limit the invention. Ad\'antageously, one or more embodiments of the present invection enable a bonnet to be securely coiq)led to a BOP body by a latching mechanism that may be unlatched in a relatively short period of time. This enables easy inspection and replacement of ram blocks, seals, and other component parts of a BOP. While the invention has been described with respect to £. limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be Umited only by the attached claims. Claims What is claimed is: [1] A bonnet lock mechanism for a blowout preventer con^rijsing: a radial lock; a radial lock displacement device; and at least one lock actuator operatively coupled to the raclial lock displacement device, wherein the radial lock is comprised of straight section, mid wherem the radial lock displacement device is adapted to radially displace the radial lock to fonn a locking engagement between a bonnet and a body of the blowout preventer. [2] A bonnet lock mechanism for a blowout preventer comprisiing; an angled surface disposed in the blowout preventer; a ktching dog having a tapered surface disposed in the boanet; and a lock actuator operatively coupled to the latdiing dog, wherem the lock actuator is adq)ted to move the latching dog such that the latching dog is in locking engagement with the mgled surface of the blowout preventer. [3] The bonnet lock mechanism of claim 2, wherein the latcliing dog comprises a corresponding dovetail-sh^ed recess, and wherein the lo<:k actuator is coupled to the latching dog by a shaft having generally dovetail-iihaped protrusion that dovetail-sh recess in lat dog.> 4. A bonnet lock mechanism substantially as herein described with reference to the accompanying drawings.

Documents:

381-che-2004-abstract.pdf

381-che-2004-claims duplicate.pdf

381-che-2004-claims original.pdf

381-che-2004-correspondnece-others.pdf

381-che-2004-correspondnece-po.pdf

381-che-2004-description(complete) duplicate.pdf

381-che-2004-description(complete) original.pdf

381-che-2004-drawings.pdf

381-che-2004-form 1.pdf

381-che-2004-form 19.pdf

381-che-2004-form 26.pdf

381-che-2004-form 3.pdf

381-che-2004-form 5.pdf