Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
  • C10B33/00—Discharging devices; Coke guides
  • C10B33/006—Decoking tools, e.g. hydraulic coke removing tools with boring or cutting nozzles

Definitions

• the embodiments described herein generally relate to devices for removing coke from containers such as coking drums used in oil refining, and more specifically to devices for shifting between nozzle modes in a decoking tool used in oil refining coke drums.
• the heated oil releases its valuable hydrocarbon vapors which are then sent to distilling towers where they form condensate (including, among other things, gas, naphtha and gas oils) which can be further processed into more useful products, leaving behind, through the combined effect of temperature and retention time, solid petroleum coke.
• This coke residue must be broken up in order to remove it from the vessel, and is preferably accomplished by using a decoking (or coke cutting) tool in conjunction with a decoking fluid, such as high pressure water.
• Such a tool can include a number of nozzles for removing coke such as, for example, a drill bit with both drilling and cutting nozzles.
• the decoking tool can be lowered into the vessel through an opening in the top of the vessel, and the high pressure water supply can be introduced into the decoking tool to supply decoking fluid to the desired nozzles of the decoking tool.
• the diversion plate can be configured to provide selective fluid communication between a source of pressurized decoking fluid and a first nozzle and a second nozzle.
• the diversion plate can define a tool-engaging surface thereon.
• the control rod can be coupled to the diversion plate.
• the shifting mechanism can be cooperative with the diversion plate through the control rod such that a change in decoking fluid pressure imparted to the shifting apparatus produces selective rotary movement in the diversion plate through the control rod.
• the biasing member can be responsive to changes of the decoking fluid pressure such that the biasing member is configured to temporarily unseat the tool-engaging surface of the diversion plate from an adjacent surface of a decoking tool during the change in the decoking fluid pressure.
• the biasing member can maintain the diversion plate and the decoking tool in a state of separation during at least a portion of a time prior to relative rotary movement.
• a mode-shifting apparatus for use in a fluid jet decoking tool may include a diversion plate, a control rod, a shifting mechanism, and a biasing member.
• the diversion plate may be configured to provide selective fluid communication between a source of pressurized decoking fluid and a first nozzle and a second nozzle.
• the diversion plate can define a tool-engaging surface thereon.
• the control rod can be coupled to the diversion plate.
• the control rod may include a ratcheting mechanism.
• the shifting mechanism may include an actuator sleeve engaged with the ratcheting mechanism of the control rod.
• the actuator sleeve can be engaged with an actuator pin carrier that is biased axially by a shift biasing member.
• a change in decoking fluid pressure imparted to the shifting apparatus can produce selective rotary movement in the diversion plate through the control rod.
• the biasing member can be responsive to changes of the decoking fluid pressure such that the biasing member is configured to temporarily unseat the tool-engaging surface of the diversion plate from an adjacent surface of a decoking tool during the change in the decoking fluid pressure.
• the biasing member can maintain the diversion plate and the decoking tool in a state of separation during at least a portion of a time prior to relative rotary movement.
• FIG. 1 schematically depicts a cutaway view of a decoking tool with a mode shifting apparatus according to one or more embodiments shown and described herein;
• FIGS. 2A-2C schematically depicts the mode shifting apparatus of FIG. 1 in a depressurized state according to one or more embodiments shown and described herein;
• FIG. 3A-3C schematically depicts the mode shifting apparatus of FIG. 1 in a partially pressurized state according to one or more embodiments shown and described herein
• FIG. 4A-4D schematically depicts the mode shifting apparatus of FIG. 1 in a fully pressurized state according to one or more embodiments shown and described herein;
• FIG. 5 schematically depicts a different embodiment of the mode shifting apparatus in a depressurized state according to one or more embodiments shown and described herein;
• FIG. 6 shows a top perspective view of the mode-shifting apparatus of FIG. 1, highlighting the placement of orifice plates in a set of paired axial passageways formed in the diversion plate;
• FIGS. 7 A and 7B show the presence of oil as a damping fluid in two different operating states of a shifting apparatus according to the prior art.
• the decoking tool 200 can comprise a fluid delivery path 202 for supplying decoking fluid to one or more cutting nozzles 204A or boring nozzles 204B via a mode-shifting apparatus 1. Accordingly, the mode-shifting apparatus 1 can be operated to selectively direct decoking fluid to any of the one or more cutting and boring nozzles 204A, 204B.
• Shifting mechanisms such as, for example, an AutoShift by Flowserve Corporation of Irving, TX, USA, can be used to selectively direct the flow to the desired cutting nozzles, i.e., either the cutting nozzles or the drilling nozzles, depending on which part of the decoking operation the tool is in at that time.
• decoking fluid can be pressurized and made to pass through one or more the nozzles 204A, 204B in response to one or the other of a drilling mode of operation or a cutting mode of operation. Details pertaining to nozzle and channel placement and operation can be seen in US Patent 6,644,567 that is owned by the Assignee of the present application and the pertinent portions of which are incorporated herein by reference.
• the mode-shifting apparatus 1 can comprise delivery channels 22A, 22B for the flow of decoking fluid through the diversion body 20 and to the nozzle sets.
• the channels 22A can be diametrically opposed to one another about the axial dimension of a diversion body 20 to promote fluid communication between the decoking fluid that enters a perforate diversion plate 40 through axial passageways 42 and the cutting nozzles 304A, while another set of channels 22B can be used to promote fluid communication between the decoking fluid that enters the diversion plate 40 through axial passageways 42 and the boring nozzles 304B; as with the first channels 22A, the second channels 22B can be placed diametrically opposed to one another in diversion plate 40.
• the axial channels 22A, 22B can terminate at an upper surface 24 of the diversion body 20.
• a biasing apparatus 10 can be formed into or mounted onto a lower portion of a diversion body 20 of mode-shifting apparatus 1.
• the mode-shifting apparatus 1 can be outfitted with any number of passageways and corresponding channels for supplying pressurized fluid to any number of nozzles; the present embodiment shows two of each.
• the passages can be configured such that pressurized fluid traversing the upper surface 24 of the diversion body 20 can directed any subset of the one or more nozzles 204A, 204B (FIG. 1).
• At least one of the fluid passageways formed by the cooperation of axial passageways 42 and channels 22A, 22B can be used such that upon delivery of the decoking fluid through the respective channel (presently shown as channel 22B), fluid communication is established such that the fluid can be used to impart pressure to the surfaces of other components (such as piston 140 mentioned below in conjunction with FIGS. 2A, 3 A and 4A) to facilitate selective movement of such components.
• a control rod (also referred to herein as diversion plate shaft, made up of a lower shaft and an upper shaft) 30 is a rotatable shaft that couples diversion plate 40 to the biasing apparatus 10 so that changes in pressure (i.e., depressurizations and repressurizations) applied to the biasing apparatus 10 can selectively cause the diversion plate 40 to rotate. Rotations of the diversion plate 40 can be utilized to switch between the aforementioned drilling and cutting modes, i.e., by selectively providing pressurized fluid to the desired passage of the diversion body 20.
• Control rod 30 may be made from an upper and lower portion that are joined together, or may be fabricated as a single piece.
• the diversion plate 40 can define a generally cylindrical shape about its axis of rotation R, and can include paired axial passageways 42 that terminate in apertures at the upper surfaces 44 and lower surfaces 46 of the diversion plate 40. In this way, the diversion plate 40 acts like a valve between fluid delivery path 202 (FIG. 1) and the drilling and cutting nozzle sets.
• a flowpath can be formed with the channels that lead to one or the other of the drilling and cutting nozzle sets.
• a pressurized source of decoking fluid that enters the top of diversion plate 40 is by the action of the biasing apparatus 10 routed to a corresponding set of drilling nozzles and cutting nozzles through axial passageways 42 and one or another set of channels.
• the various aspects of the present disclosure can be used to reduce these frictional forces by lifting the diversion plate 40 away from the upper surface 24 of the diversion body 20 during transient and/or peak pressure conditions (e.g., as the pressure applied to the diversion plate 40 changes from a relatively high state to a relatively low state, as the pressure applied to the diversion plate 40 changes from a relatively low state to a relatively high state, when the pressure applied to the diversion plate 40 is at a relatively high state, when the pressure applied to the diversion plate 40 is at a relatively low state or changes to a relatively low state, or combinations thereof).
• peak pressure conditions e.g., as the pressure applied to the diversion plate 40 changes from a relatively high state to a relatively low state, as the pressure applied to the diversion plate 40 changes from a relatively low state to a relatively high state, when the pressure applied to the diversion plate 40 is at a relatively high state, when the pressure applied to the diversion plate 40 is at a relatively low state or changes to a relatively low state, or combinations thereof).
• the biasing apparatus 10 can comprise one or more axial springs 100 (e.g., a biasing member) in the form of axially- aligned disks that are situated between and in contact with respective surfaces of a lower cover plate 105 and a control rod sleeve 110.
• the one or more axial springs 100 can bias the diversion plate 40 in an unseated position relative to mode- shifting apparatus 1.
• the diversion plate 40 can be biased to an unseated position such that an axial clearance or gap Gl is formed between the upper surface 24 of the diversion body 20 and the lower surface 46 of diversion plate 40.
• the gap Gl can be any distance sufficient to physically separate the diversion body 20 from the diversion plate 40, i.e., the gap Gl places the diversion body 20 out of contact with the diversion plate 40. More particularly, the axial lift springs 100 cause the gap Gl to be of a magnitude compatible with the flow and pressure of the decoking fluid.
• the upper surface of the control rod sleeve 110 can be in axial contact with a lower surface of actuator sleeve 120 that defines a spiral groove 122 therein.
• An actuator pin (also called guide pin) 125 can be secured within an actuator pin carrier 130 such that the generally linear upward or downward movement of the actuator pin 125 can - through its cooperation with the spiral groove 122 formed about the rotational axis R of the actuator sleeve 120 - impart rotational movement to the actuator sleeve 120.
• the actuator sleeve 120 is cooperative with the control rod 30 using a ratchet mechanism 147 that enables the sleeve 120 to selectively rotate the rod 30.
• the sleeve 120 is connected to the diversion plate 40 through a ratchet-pawl arrangement in ratchet mechanism 147, along with control rod (i.e., shaft) 30.
• control rod i.e., shaft
• the sleeve 120, control rod 30 and diversion plate 40 rotate in response to an increase in decoking fluid pressure being applied to the top surface of piston 140 (which would correspond to the generally downward movement of the actuating pin 125 and carrier 130 in response to the increase in fluid pressure) along with the radially spring-biased selective engagement of ratchet mechanism 147.
• the engagement of the ratchet mechanism 147 with pawl 124 that is coupled to the actuator sleeve 120 to selectively rotate the control rod 30 can ensure that the rotational force imparted to the actuator sleeve 120 by the actuator pin 125 is transmitted to the control rod 30 and the diversion plate 40 during the appropriate one of the pressurization and depressurization steps.
• the ratchet mechanism 147 can act as a positioning mechanism in cooperation with the control rod 30 to ensure precise clocking of the diversion plate 40 in the desired direction.
• the diversion plate 40 can be clocked in ninety degree increments for a mode-shifting apparatus 1 with a pair of channels (such as channels 22A, 22B shown) for each of the drilling and cutting modes.
• the ratchet mechanism 147 can be configured to cause the actuator sleeve 120 to engage the control rod 30 to when the actuator sleeve rotates in one direction and to not engage the control rod 30 when the actuator sleeve rotates in another direction. Accordingly, as mentioned above, the ratchet mechanism 147 can act to cause the control rod 30 to rotate during only one portion of the pressurization/depressurization cycle.
• the spiral grooves 122 could be placed in the actuator sleeve 120 in one orientation (for example, to define a right-handed helicoid) such that the upward movement of the actuator pin 125 that accompanies depressurization from the fluid pushes against an upper surface of the spiral groove 122.
• the spiral grooves 122 could be placed in the actuator sleeve 120 to define a left-handed helicoid so that the downward movement of the actuator pin 125 that accompanies pressurization pushes against a lower surface of the spiral groove 122.
• the orientation of the ratchet mechanism 147 ultimately determines when the rotation of the control rod 30 and diversion plate 40 takes place, as the engagement of spring-loaded pawls (not shown) with corresponding ratchet wheel teeth (not shown) of the ratchet mechanism 147 can be made to cooperate with one or the other of the aforementioned upward and downward movements that accompany fluid pressurization or depressurization.
• the configuration of the actuator sleeve 120 as having its spiral grooves 122 oriented within the actuator sleeve 120 as a right- handed helicoid or a left-handed helicoid is merely a matter of design preference to be chosen in conjunction with the orientation of ratchet mechanism 147.
• the diversion plate 40 rotate upon pressurization (rather than upon depressurization). While ordinarily, such shift- upon pressurization may be rendered more difficult due to the increased frictional forces between the adjacent surfaces that are being forced to rotate relative to one another, the inclusion of the lifting effect of the axial springs 100 - when used in conjunction with the remainder of the shifting mechanism 1 to produce aforementioned gap Gl - helps to not only avoid wear on the diversion plate 40, but also can be used to counteract the effect of the pressurization, thereby providing much more precise control over the movement of the control rod 30 and diversion plate 40, which in turn can produce better control over the routing of the decoking fluid through one or both of the cutting and boring nozzles.
• shift during pressurization may be advantageous because the shifting springs 135 (also called shift biasing members, or more simply, biasing members) do not require extremely high stiffness, thereby lowering the forces on the actuator pin carrier 130 and actuator pin 125, which in turn enables easier design of the tool 1.
• shifting springs 135 also called shift biasing members, or more simply, biasing members
• the one or more shifting springs 135 of the biasing apparatus 10 may be utilized to ensure that the actuator pin carrier 130 moves up when the pressure is reversed.
• the one or more shifting springs 135 engage the lower cover plate 105 and a piston 140.
• the piston 140 can be engaged with the actuator pin carrier 130 such that the piston 140 and the actuator pin carrier 130 move contemporaneously.
• the one or more shifting springs 135 can exert a force upon the piston 140 such that the piston 140 and the actuator pin carrier 130 are biased away from the lower cover plate 105.
• the diversion plate 40 can be transitioned to an unseated position to create gap Gl between the diversion plate 40 and the diversion body 20 prior to rotating the diversion plate 40.
• a portion of the decoking fluid can be utilized to apply a force upon the piston 140 in opposition to the one or more shifting springs 135.
• the pressurizing force supplied by the decoking fluid is greater than the force supplied by the one or more shifting springs 135, the one or more shifting springs 135 can be compressed through the pressure imparted by the decoking fluid on piston 140.
• the one or more shifting springs 135 can be decompressed by overcoming the decoking fluid pressure. Accordingly, the motion of the piston 140 and, thus, the actuator sleeve 120 can be controlled by the pressure of the decoking fluid with the shift-upon- pressurization or shift-upon-depressurization, as well as the direction of rotation, dictated by the configuration of the ratchet mechanism 147 and spiral groove 122 as discussed above.
• the actuator sleeve 120 (upon receipt of a downward force coming from actuator pin carrier 130 that is in turn responsive to the downward force imparted to it by piston 140 in a manner similar to - but separate from - that imparted to the shifting springs 135) can be configured to apply force to the axial springs 100.
• the control rod sleeve 110 can be in axial contact with the actuator sleeve 120.
• the axial springs 100 can be disposed between the lower cover plate 105 and the control rod sleeve 110.
• the axial springs 100 can be compressed between and exert force upon the lower cover plate 105 and the control rod sleeve 110; it is these springs 100 that dictate whether a gap Gl is formed between the lower surface of the diversion plate 40 and the adjacent upper surface of the diversion body 20.
• the control rod 30 can be configured to interact with the control rod sleeve 110.
• the control rod 30 can comprise a collar portion 32 that engages with the control rod sleeve 110. Accordingly, control rod 30 and the control rod sleeve 110 can move contemporaneously. Specifically, as force exerted upon the control rod sleeve 110 in opposition to the force exerted upon the control rod sleeve 110 by the axial springs 100 increases, the axial springs 100 can be compressed and the control rod sleeve 110 can move towards the lower cover plate 105.
• the axial springs 100 can be uncompressed, which in turn causes the control rod sleeve 110 to be upwardly moved away from the lower cover plate 105.
• the axial position of the control rod 30 and thus, the gap Gl can be controlled by the axial position of the actuator sleeve 120.
• the position of the actuator sleeve 120 can be controlled by the amount of pressure supplied by the decoking fluid.
• the axial position of the control rod 30 and the relative size of gap Gl can be controlled by the amount of pressure supplied by the decoking fluid.
• FIGS. 2A-2C depict the mode-shifting apparatus 1 in a relatively depressurized state.
• a relatively low amount of pressure is supplied downwardly to the piston 140 from the decoking fluid such that upwardly- directed force from the axial springs 100 leaves them in a generally uncompressed state.
• the spring force supplied by the shifting spring (or springs) 135 is sufficient to maintain the piston 140 in a relatively high position, i.e., relatively close to a lower surface of the diversion body 20.
• the actuator pin carrier 130 is at a relatively high position such that little (or no) downward force is applied by it to the actuator sleeve 120.
• the axial springs 100 - which are relatively unloaded in this state - have sufficient spring force to urge the control rod sleeve 110 and the actuator sleeve 120 upwards towards the shift body 107.
• the axial springs 100 have sufficient spring force, in the relatively uncompressed state, to urge the control rod 30 vertically in order to form the gap Gl (shown with particularity in FIG. 2B) between the diversion plate 40 and the diversion body 20.
• FIGS. 3A-3C depict the mode-shifting apparatus 1 in a moderately pressurized state where the axial springs 100 transition from the relatively uncompressed state depicted in FIGS. 2A-2C to a state where they are relatively compressed by increasing the pressure on the piston 140 from the decoking fluid.
• the piston 140 can be urged downward, which in turn pushes the actuator pin carrier 130 down while compressing the shifting spring 135.
• Such downward motion of the actuator pin carrier 130 can cause the actuator sleeve 120 to rotate under the influence of the actuator pin 125 interacting with the walls of the spiral groove 122 formed in the actuator sleeve 120.
• the control rod 30 can be rotated during this part of the pressurization cycle, i.e., as the pressure is increased.
• the ratchet mechanism 147 can be configured to lock with the pawl 124 of the actuator sleeve 120 and cause the control rod 30 to rotate while gap Gl (which still briefly remains from the relatively uncompressed state depicted in FIGS 2A-2C above) continues to separate the diversion plate 40 and the diversion body 20.
• the ratchet mechanism 147 can be configured to cause the control rod to rotate with the actuator sleeve 120 under an increase in pressure.
• the spiral groove 122 formed in the actuator sleeve 120 can be configured to cause the diversion plate 40 to rotate in substantially equal increments such as, for example, in one embodiment about 90°.
• the one or more shifting springs 135 provide a strong bias against the actuator pin carrier 130 to maintain the actuator pin carrier 130 and actuator pin 125 at their topmost position, the one or more shifting springs 135 do not directly provide the lifting of the diversion plate 40 prior to and/or during the rotation that accompanies mode shifting.
• the axial springs 100 can supply sufficient spring force to form the gap Gl that separates the diversion plate 40 and the diversion body 20.
• the pressure at which shifting occurs can be adjusted by varying the difference in spring constants of the one or more shifting springs 135 and the axial springs 100.
• FIGS. 7 A and 7B a comparison between the oil-based damping approach of a prior art shifting apparatus 301 (for example, the current production AutoShiftTM that is owned by the Assignee of the present invention) and the present invention (which avoids the use of oil for damping) is shown.
• the biasing apparatus 310 is mounted onto a lower portion of a diversion body 320 in a manner generally similar to that of FIG. 1. Note that in the device of the prior art, the diversion plate 340 is always in contact with the diversion body 320 through respective upper and lower contacting surfaces 346 and 324.
• FIG. 7A shows the shifting apparatus 301 of the prior art in a low pressure state; this is evidenced by the pin carrier 330 occupying the vertical uppermost part of the cavity (or volumetric region R) formed in the biasing apparatus 310; in this state, the shift springs (i.e., shift biasing members, bias springs or the like) 335 are in a relatively uncompressed state. Oil (shown by the dotted pattern) substantially fills the volumetric region R beneath the pin carrier 330 and the space surrounding the shift springs 135.
• the amount of oil used in region R is greater than that needed for lubricating the various components of the biasing apparatus 310, in order to perform a damping function (described below).
• pin 325 and pin carrier 330 traverse in a vertically up-and- down movement through cooperation with spiral actuator sleeve 380 and springs 335 in response to fluid pressure changes imparted to piston 370.
• ratchet mechanism 347 The one-way rotational nature of ratchet mechanism 347 is such that upon the pressurization step and its attendant downward movement of the pin 325 and pin carrier 330, the ratchet mechanism 347 does not permit a clocking movement present in the sleeve 380 to be imparted to the shaft S even though the downward movement by the pin carrier 330 and pin 325 causes sleeve 380 to rotate due to the pin-accepting path formed its spiralled groove 385.
• the diversion plate 340 - which is in rotational cooperation with shaft S - does not turn, thereby keeping the fluid communication between the axial passageways 342 and one or the other of the cutting nozzles 304A or boring nozzles 304B unchanged.
• the springs 335 want to expand and rotate the sleeve 380. It is noted that in the state depicted in FIG. 7B, the shift springs 335 are completely compressed and the oil is now on top of the pin carrier 330 within region R. Moreover, the pawl-based ratchet mechanism 347 allows engagement (i.e., mechanical coupling) between the diversion plate 340 (through upper and lower shaft S) and sleeve 380.
• the upward force in springs 335 is sufficient to overcome the fluid force, thereby loosening the connection and attendant surface friction between the diversion plate 340 and diversion body 320; such frictional reduction permits relative rotation between the diversion plate 340 and diversion body 320. Furthermore, once the springs 335 start expanding, they are able to accelerate the upward motion of carrier 330 and coupled diversion plate 340 rotation.
• the overall effect of the axial springs 100 on lifting the diversion plate 40 before rotation, taken in conjunction with the automated shifting action of the mode-shifting apparatus 1, is such that friction associated with the rotational forces of the mode shifting is reduced between the diversion plate 40 and the diversion body 20.
• friction associated with the rotational forces of the mode shifting is reduced between the diversion plate 40 and the diversion body 20.
• wear that would otherwise happen when plates are in contact with one another under pressure is reduced.
• such reduced friction allows the relative rotation among the plates to be achieved with less power.
• the reduced friction can also facilitate more smooth and accurate rotation that may be especially helpful in configurations where the shift takes place upon pressurization (although such lower friction may also be helpful in shifting- upon-depressurization configurations as well).
• an oil-free mode of operation corresponds to being able to achieve tool damping without the need for a damping fluid such as oil; such mode is not meant to imply that oil for lubricant purposes is not required.
• a damping fluid such as oil
• the relevant portions of a decoking tool that ordinarily may require oil as a damping fluid and are designed in accordance with the invention disclosed herein may be simplified to be oil-free relative to such damping fluids.
• FIGS. 4A-4D show that a further increase in pressure causes the piston 140 and actuator pin carrier 130 to apply increased pressure upon the actuator sleeve 120 such that the mode-shifting apparatus 1 is in a fully (or elevated) pressurized state where the pressure is large enough to urge the actuator sleeve 120 downward towards the control rod 30 and the control rod sleeve 110, while the diversion plate 40 is also simultaneously forcing the control rod 30 against the control rod sleeve 110. Accordingly, the axial springs 100 can be compressed, as is schematically depicted in FIG. 4D. As a result, the diversion plate 40 can be move downwards towards the diversion body 20.
• the lower surface 46 of the diversion plate 40 and the upper surface 24 of the diversion body 20 can be urged into contact, as is schematically depicted in FIG. 4B.
• another gap G2 can be formed between the actuator sleeve 120 and the shift body 107, as is schematically depicted in FIG. 4C.
• the axial springs 100 can move the diversion plate 40 upwards to create gap Gl (FIG. 3B), while also removing gap G2 that was above the top of actuator sleeve 120 (FIG. 4C). Likewise, the piston 140, actuator pin carrier 130 and actuator sleeve 120 can be lifted by the axial springs 100.
• control rod 30 may remain stationary during the increasing pressure portion of the pressure cycle and rotate during the decreasing pressure portion of the pressure cycle.
• the rotational direction of the actuator sleeve 120 can be reversed or the direction of the ratchet mechanism 147 can be reversed.
• the diversion plate 40 can be unseated with respect to the diversion body 20, while shifting between modes (e.g., drilling and cutting modes) to reduce frictional forces and concomitantly extend the mean time between repair (MTBR) of decoking tool 200 and/or the mode-shifting apparatus 1.
• modes e.g., drilling and cutting modes
• the biasing apparatus 210 can comprise a lower control rod 212 and an upper control rod 214 that are engaged with one another and operate in a manner analogous to the control rod 30 (FIGS. 2A-4D).
• the lower control rod 212 can include a ratchet mechanism 147 that cooperates with a pawl 124 of the actuator sleeve 120, as is described herein above.
• the upper control rod 214 is engaged with the diversion plate 40 (not depicted in FIG. 5) such as via an extending rod. Accordingly, the diversion plate 40 can be configured to lift axially and rotate about the axis of rotation R by the upper control rod.
• the biasing apparatus 210 can further comprise one or more axial springs 218 (e.g., biasing members) disposed between the lower control rod 212 and the upper control rod 214.
• the spring force supplied by axial springs 218 can be configured such that the upper control rod 214 can be lifted at decoking fluid pressures less than or equal to a predetermined pressure.
• the upper control rod 214 can be raised by a gap G3 over its lowermost position, which in turn causes gap Gl (FIG. 2B) to separate the diversion plate 40 from the diversion body 20 (FIG. 2A).
• the spring constant of the axial springs 218 can be set such that the gap G3 is formed at a predetermined pressure that is lower than the pressure needed to compress the shifting spring 135.
• the predetermined pressure can be set to any decoking fluid pressure that is less than the decoking fluid pressure required to move the piston 140 from its upper most position.
• the axial springs 218 can be configured such that gap Gl (FIG. 2B) exists prior to and during any rotational motion of the diversion plate 40 (FIG. 2A).
• Axial springs may be employed in conjunction with a shift biasing member to allow frictional forces between adjacent surfaces of a flow diversion plate and the body of the decoking tool to be reduced/eliminated through the creation of slight axial gaps prior to any rotational movement between them.
• the pressure of the water passing through the tool may be between about 1500 pounds per square inch (psi) and an elevated about 5000 psi (or higher). In one form, such elevated pressure may be between about 4000 and 6000 psi.
• the embodiments described herein can allow the mode-shifting apparatus 1 to complete shifting at higher residual pressures. This in turn allows completion of the shifting in less time, and more particularly means that the decoking tool valve (DCV) will only have to go to a "prefill” position rather than to a "bypass” position, and that in so doing can increase the life of the DCV.
• DCV decoking tool valve
• a top perspective view of the mode shifting apparatus 1 reveals how the diversion plate 40 cooperates with the diversion body 20 in order to selectively send high pressure flow to one of the other of the cutting or boring nozzles 204A, 204B through respective flowpaths 304A and 304B.
• the axial passageways 42 of the diversion plate 40 are arranged about the rotational axis of the mode shifting apparatus 1 in two sets of two diametrically-opposed holes such that one set leads to the flowpath 304A that correspond to the cut nozzles, while the other set leads to the flowpath 304B that corresponds to the bore nozzles.
• These paired axial passageways 42 are configured to align with the axial channels 22 on diversion body 20, where at any given time, one of the two sets may have the flow therethrough restricted by orifice plates 48.
• the diversion plate 40 ensures that unrestricted pressurized flow is provided to the proper set of the cutting nozzles 204A or the boring nozzles 204B.
• the cutting nozzles 204A - which do not need water at this stage - could be temporarily blocked during mode shifting apparatus 1 operation.
• small amounts of flow at reduced pressure is provided to the cutting nozzles 204A.
• a typical elevated operating pressure results in no gap between the diversion plate 40 and the diversion body 20.
• Both the actuation pin carrier 130 and piston 140 are all the way down.
• the shift springs 135 and axial springs 100 are fully compressed, while the diversion plate 40 remains stationary (i.e., does not rotate).
• Decoking fluid flow proceeds freely to the cutting nozzles 204A through aligned open holes in the diversion plate 40 and diversion body 20, while the orifice plate 48 restricts decoking fluid flow to the boring nozzles [0043]
• the decoking fluid pressure drops from this elevated pressure to more intermediate range.
• no gap forms yet between the diversion plate 40 and the diversion body 20, and the diversion plate 40 remains stationary.
• Flow continues relatively freely to the cutting nozzles 204A through the aligned openings in the diversion plate 40 and diversion body 20, while the orifice plates 48 restrict flow to the boring nozzles 204B.
• the diversion plate 40 pops up, causing gap Gl to be formed between the diversion plate 40 and the diversion body 20.
• the actuation pin carrier 130 and piston 140 are all the way up such that the axial springs 100 become uncompressed.
• the presence of the gap Gl - as well as the unseating of the orifice plates 48 from the axial passageways 42 - ensures that decoking fluid flows not just to the cutting nozzles 204A, but to the boring nozzles 204B as well, as the pressurized decoking fluid has a path through all of the axial passageways 42 formed in the diversion plate 40.
• gap Gl that is present under the diversion plate 40 remains, while the actuation pin carrier 130 and piston 140 have moved into their lowest position; in one form, this may relate to a total liner movement of about 0.75 inches.
• the shifting springs 135 are compressed, while the diversion plate completes its 90° rotation.
• the actuation pin carrier 130 is in contact with the control rod sleeve 110 through actuator sleeve 120 such that they cooperate to start compressing the axial springs 100 that are underneath the control rod sleeve 110. Decoking fluid flow continues through both the cutting and boring nozzles 204A, 204B.
• the lubricating flowpath or reservoir that is formed in a region of the biasing member 10 that permits relative movement of the actuator pin 125 and actuator pin carrier 130 is configured such that a substantial majority of an oil or related lubricating fluid placed therein does not reside in the portion of the region that is above the carrier 30.
• such a configuration is deemed within the present invention to be oil-free, as it avoids the need for excess oils for damping and other non- lubricating functions.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Chemistry (AREA)
• Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
• Earth Drilling (AREA)
• Multiple-Way Valves (AREA)
• Fluid-Damping Devices (AREA)
• Auxiliary Devices For Machine Tools (AREA)
• Actuator (AREA)
• Fluid-Pressure Circuits (AREA)

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• 2014
  • 2014-11-25 WO PCT/US2014/067212 patent/WO2015077740A1/en active Application Filing
  • 2014-11-25 MX MX2016006737A patent/MX2016006737A/es unknown
  • 2014-11-25 BR BR112016011944-4A patent/BR112016011944B1/pt active IP Right Grant
  • 2014-11-25 DE DE112014007345.8T patent/DE112014007345B4/de active Active
  • 2014-11-25 DE DE112014005371.6T patent/DE112014005371B4/de active Active
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