Abstract:
A compression generator uses a plurality of jackbolts threadedly engaged at a spaced apart relation about a bolt circle in a main core element. The main core element is releasable interlocked by threads, bayonet connection or other form of fasting system with the mounting element forming a fixed part of the mechanical connection. The jackbolts torqued to generate a pushing force in an axial direction for compressing a moveable part of the mechanical connection against a compression seat for forming a mechanical connection between juxtaposition fixed and moveable parts.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     Not applicable  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a compression generator using a plurality of jackbolts to apply a mechanical load against a compression member for forming a mechanical connection between opposing fixed and moveable parts, and more particularly, the compression generator uses jackbolts threadedly engaged to a main element which is in turn releasable joined to a fixed part to generate friction by transmitting a pushing force against a surface of a moveable part. The main element may take the form of a core releasable engaged with a support and carrying the jackbolts for compressing a compression element against a compression seat.  
         [0004]     2. Description of the Prior Art  
         [0005]     One aspect of the present invention is addressed to securing pipes in an end to end relation for creating a high security joint between the pipes to resist the stress and strain encountered in sub-sea environments as, for example, commonly encountered in the offshore petrochemical industry. One intended use in such a sub-sea environment is the connection of large diameter pipes so-called risers, which connect an oil well on the seabed with a terminal at the water surface. When connecting pipe elements using friction to obtain a locking effect in a sub-sea environment, it is difficult with existing technology to withstand the strain occurring when the pipe joint is exposed to waves, axial tensions, vibrations, and loads directed sideways to the extended length of the joined pipes. The reliability of friction as the locking mechanism is therefore often inadequate.  
         [0006]     Conventional technology relies solely on the application of torque to one thread in pipe couplings in order to create friction for locking joining male and female elements. This type of friction locking is not always reliable to form a sufficiently secure locking when the locking operation occurs in sub-sea environments where the pipe joints are exposed to sever localized strains. A single bolted joint for pressing two elements apart is detrimentally sensitive to vibrations causing unintentionally loosing of the bolted joint. The present invention provides an new frictional locking system using an axial friction device for pressing mechanical elements apart in such a way that friction is created between the friction device and two or more mechanical elements comprising part of the construction.  
         [0007]     Another aspect of the present invention is addressed to using compression generators for assembling components in diverse machinery but particularly pressing a component part against a sealing surface to contain pressurized fluid mediums. Examples of such machinery include high pressure plunger pumps and air compressors powered by prime movers generally having 1000 or more horsepower. Such machinery is frequently located in hostile environments where servicing components subject to wear and tear maybe required at regular intervals. Plunger pumps, for example, include a valve manifold containing suction and pressure valves seated by threaded tubes driven against a closure plate by directing impact blows to a torque bar inserted transversely in sidewall openings in the tubes.  
         [0008]     It is an object of the present invention to provide a compression generator using friction locking to achieve a considerably higher clamping force by the provision of several jackbolts fitted in threads in either a threaded male or female element, which are used for pressing the friction element against the other element of the joint so that friction is created and the load that gives rise to the desired friction is thus divided between several separate jackbolts.  
         [0009]     It is a further object of the present invention to generate a greater and evenly distributed frictional locking for joining pipes in an end-to-end relation in a joint than in previously used technology to produce a joint considerably more resistant to vibrations and axial, radial and sideway directed strains.  
         [0010]     It is another object of the present invention to provide a compression generator using friction locking established by a construction and arrangement of parts constructed to fit together in a simple and quick manner.  
         [0011]     It is another object of the present invention to provide a compression generator using jackbolts to inhibit sliding movement between members forming a barrier used to confine a volume of highly pressurized fluid.  
         [0012]     It is another object of the present invention to provide a compression generator using jackbolts to generate sufficient friction to prevent unwanted leakage of pressurized fluid between seated sealing surfaces.  
         [0013]     It is another object of the present invention to provide a compression generator using jackbolts for installing an access plug in a manifold using a core element to form a jackbolt assembly for use as a mechanically operative stress-generating unit releasable attached to the manifold.  
         [0014]     It is another object of the present invention to provide a compression generator using jackbolts for installing an access plug in a manifold using a core element to form a jackbolt assembly and a pull back restraint for use as a mechanically operative stress-generating unit releasable attached to the manifold.  
         [0015]     It is another object of the present invention to form a compression generator having a support juxtaposition from a compression seat in a manifold closed by a core releasable interlocked with the manifold and carrying a compression element between the core and the compression seat such that a plurality of jackbolts threadedly engaged with the core compresses the compression element against the compression seat.  
         [0016]     It is another object of the present invention to provide a compression generator to more evenly distribute a compression force about a surface area where friction is created by the compression generator to form a joint between a support juxtaposition from a joining member to form a joint considerably more resistant to vibrations and axial, radial and sideway directed forces.  
       SUMMARY OF THE INVENTION  
       [0017]     According to the present invention there is provided a compression generator including a plurality of jackbolts receiving torque to generate a pushing force in an axial direction thereof for forming a mechanical connection between opposing fixed and moveable parts, the jackbolts threadedly engaged to a main element which is in turn releasable joined to the fixed part of the mechanical connection to generate friction by transmitting the pushing force against a surface of the moveable part of the mechanical connection.  
         [0018]     The present invention also provides a compression generator including a mounting element juxtaposition from a compression seat, a core releasable interlocked with the mounting element; a compression element between the core and the compression seat, and a plurality of jackbolts torqued by threadedly engagement with the core for compressing the compression element against the compression seat.  
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0019]     The present invention will be more fully understood when the following description is read in light of the accompanying drawings in which:  
         [0020]      FIG. 1  is a plane view of a first embodiment of the a compression generator embodying the features of the present invention;  
         [0021]      FIG. 2  is a sectional view taken along lines  2 - 2  of  FIG. 1 ;  
         [0022]      FIG. 3  is a plane view taken along lines  3 - 3  of  FIG. 2 ;  
         [0023]      FIG. 4  is a sectional view taken along lines  4 - 4  of  FIG. 2 ;  
         [0024]      FIG. 5  is an isometric illustration of a second embodiment of a compression generator embodying the features of the present invention;  
         [0025]      FIG. 6  is a sectional view taken along lines  6 - 6  of  FIG. 5 ;  
         [0026]      FIG. 7  is a plane view taken along lines  7 - 7  of  FIG. 5 ;  
         [0027]      FIG. 8  is a sectional view similar to  FIG. 6  and illustrating a third embodiment of compression generators embodying the features of the present invention;  
         [0028]      FIG. 9  is a plane view taken along lines  8 - 8  of  FIG. 8 ;  
         [0029]      FIG. 10  illustrates a third embodiment of compression generator according to the present invention for installing a high-pressure fluid orifice in an accumulator assembly; and  
         [0030]      FIG. 11  is a sectional view taken along lines  11 - 11  of  FIG. 10 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0031]      FIGS. 1-4  illustrate a first embodiment of a compression generator  10  for generating pushing forces in relative opposite directions e.g. along axial paths, sufficient to form a frictional interconnection between elongated pipe members  12  and  14  embodied as relatively large diameter pipes of the type used in sub-sea installations for offshore oil and gas wells. The pipe member  12  includes an end portion  16  containing a centrally located annular ring section  18  bounded by annular groves  20  and  22  terminating at annular ring sections  24  and  26  of reduced outside diameters as compared with the outside diameter of the pipe  12 . The pipe member  14  includes a connector portion  28  constructed with at least one, preferably four, threaded bores  30  arranged with the central axes  30 A of each bore, preferable lying in a common plane that is perpendicular to the longitudinal and central axis of the pipe member  14 . When four threaded bores are provided, they are preferably arranged as opposed pairs having the axes  30 A of a pair of coaxially arranged. Threads on the external peripheral edge of a disk shaped carrier  32  engage with the threads of each of the bores  30  for mounting the carrier in a load transferring relation in the connector portion  28  of the pipe member  14 . The thickness of the disk shaped threaded carrier approximates the wall thickness of the end portion  28  of the pipe member  14 . The threaded carrier  32  is provided with a plurality of drilled and tapped holes  32 A spaced about a bolt circle centered on the axis  30 A to receive a jack bolt  38  having a sufficient length to present an end portion extending into an abutting relation with an arcuate compression shoe  34 . The compression shoe includes an arcuate base  36  containing two parallel and side-by-side compression ribs  39  spaced apart by a central recess  40  to establish interlocking engagement with the annular support ring section  18  and the annular groves  20  and  22 , as shown in  FIG. 1 . This arcuate inter fitting relationship of the compression shoe pressed against the support ring section  18  by the pushing force generated by the jack bolts  38  establishes a mechanical interconnection between the large diameter pipes of great and long lasting integrity. Positioning of the compression shoe in compression generator  10  before generating the pushing forces is limited to linear movement by sliding of a spindle  42  in bore  32 B along axis  30 A while joined by a T-shaped end  44  mounted in a corresponding shaped T-slot formed in the arcuate base  34 . A nut  46  mounted on an outwardly extending threaded end of the spindle  42  is dimensioned to seat in a counter bore  32 C to provide guided movement of the spindle throughout a desired range in an annular gap between the end portions  16  and connector portion  28 .  
         [0032]      FIGS. 5, 6  and  7  illustrate a second embodiment of compression generators  50  according to the present invention embodied as retainer cores for suction and pressure valves  52  and  54 , respectively in a valve manifold  56 . Two independent collars  58  are attached by threaded fasteners  60  to the sidewalls of the valve manifold  56 . Each collar has a central opening containing screw threads, bayonet lugs, or component parts of other suitable fastening systems for interlocking engagement to mount a disk shaped access plug  62 . In this illustrated embodiment, the collar and plug for each compression generator have mating screw threads. Each disk shaped access plug contains a plurality of threaded bores distributed about a bolt circle and receiving jackbolts  64  for generating pushing forces along axial paths corresponding to the longitudinal central axes of the jackbolts. This assembly the jackbolts form a mechanically operative stress-generating unit releasable attached to the manifold.  
         [0033]     A hex nut member  66  is located in the central face area of the collar for torquing the access plug during assembly and disassembly of the access plug in the collars  58 . A centrally located aperture is threaded to engage a threaded end of an eyebolt  68  used as an aid when handling the access plug. The suction valve  52  is mounted in a holder  70  pressed by operation of the jackbolts  64  against a mounting surface located in the valve manifold  56  to present the suction valve  52  in an operative position extending in a pressure chamber  72  so that a spring biased valve plunger  52 A of the valve is seated against a valve seat provided in a valve manifold  56 . In this manner, the jackbolts are used to inhibit sliding movement between members forming a barrier used to confine a volume of highly pressurized fluid and generate sufficient friction to prevent unwanted passage of pressurized fluid between seated sealing surfaces. The pressure valve  54  is pressed by operation of the jackbolts  64  against a mounting surface  74  formed in a high pressure exhaust chamber of the valve manifold  56  and thereby position a spring biased valve plunger  54 A against a valve seat located in a in a valve manifold  56 . A fluid medium, such gas, or liquid is acted on by operation of a piston reciprocated in a chamber communicating with a port  56 A.  
         [0034]      FIGS. 8 and 9  illustrate a third embodiment of compression generators  80  according to the present invention embodied as a retainer for providing access to a suction valve  82  in a valve manifold  84 . A core element is provided by a disk shaped retainer  86  is secured by a threaded periphery to the threads in an aperture formed in the sidewall of the valve manifold  84 . An alternative to the use of screw threads for mounting the retainer to the valve manifold is bayonet lugs or component parts of other suitable fastening systems. The disk shaped access retainer contains a plurality of threaded bores distributed about a bolt circle and receiving jackbolts  88  for generating pushing forces along axial paths corresponding to the longitudinal central axes of the jackbolts. This assembly of jackbolts serves to provide a mechanically operative stress-generating unit releasable attached to the manifold.  
         [0035]     A hex nut cavity  90  is located in the central face area of the retainer for torquing the retainer during assembly and disassembly of a suction valve cover  92  in the manifold. The suction valve cover  92  is pressed into seating engagement against mounting surface  94  by operation of the jackbolts  88 , which also maintains an O-ring in an annular recess seated against the annular sidewall  96  extending to the mounting surface. The use of the jackbolts facilitate removal of the retainer and the suction valve cover for routine inspection and servicing of a suction valve mounted in the valve manifold and generate sufficient friction to prevent unwanted passage of pressurized fluid between seated sealing surfaces.  
         [0036]      FIGS. 10 , and  11  illustrate a third embodiment of compression generators  100  according to the present invention embodied as retainers  102  for installing a high pressure fluid orifice  104  at an end of an accumulator assembly  106  forming part of a high pressure waterjet system. A core element is provided by a disk shaped configuration of the retainer  102  mounted by a threaded periphery to the threads in an aperture formed in an enlarged bore at the end portion of a cylindrical member  108 . The disk shaped retainer  102  contains a plurality of threaded bores distributed about a bolt circle and receiving jackbolts  110  for generating pushing forces along axial paths corresponding to the longitudinal central axes of the jackbolts. This assembly of jackbolts also serves to provide a mechanically operative stress-generating unit releasable attached to the cylindrical member  108 . A central bore  112  in the disk shaped retainer  102  allows a mechanically free passage of a reduced diameter nozzle portion of the high-pressure fluid orifice  104 . The high-pressure fluid orifice  104  has an enlarged cylindrical base  114  pressed into a seated, fluid tight engagement juxtaposition from a compression seat formed by mounting surfaces  116  by operation of the jackbolts  110  without the use of an O-ring or other form of a seal.  
         [0037]     While the present invention has been described in connection with the preferred embodiments of the various figures, it is to be understood that other similar embodiments may be used or modifications and additions may be made to the described embodiment for performing the same function of the present invention without deviating there from. Therefore, the present invention should not be limited to any single embodiment, but rather construed in breadth and scope in accordance with the recitation of the appended claims.