Variable length/capacity elevator links

Information

  • Patent Grant
  • 6520709
  • Patent Number
    6,520,709
  • Date Filed
    Monday, April 24, 2000
    24 years ago
  • Date Issued
    Tuesday, February 18, 2003
    21 years ago
Abstract
Multi-piece elevator links, which may be of variable length or capacity or both, are produced by cutting a unitary link into two parts and connecting different combinations of shanks and link ends to form the desired elevator link. Rotation of the link ends with respect to the shank may be prevented. Adapters may be employed between the shank and the link ends to provide varying connections.
Description




TECHNICAL FIELD




The present invention relates generally to elevator links (bails) and more particularly to a method and apparatus for varying the length of elevator links composed of multi-piece sections which provide for adjustable lengths and tonnage capacities, and for interchangeable link ends and adapters, and for such other structures and methods as may be herein disclosed.




BACKGROUND ART




In general, elevator links (also known as bails) are attached between the elevator and the traveling block of a drilling rig. The links connect the elevator to the hook of the traveling block which hangs on a number of steel cables from the crown block in the top of the drilling rig. These links are used for linking drill pipe, casing, and tubing, and for lowering them into the hole. The elevator links bear the weight of the drill string as does the elevator swivel.




Traditionally, one-piece elevator links comprise a shank with an eye at each end of the shank manufactured as a single piece from alloy steel or other well known suitable materials. Links are commonly produced in set lengths. Links are also commonly designed and produced to be capable of supporting a given, set tonnage. The interchangeability and connectivity of links, elevators, and hooks are based on tonnage size classes. There is thus a need for elevator links of various lengths as well as for elevator links capable of supporting various tonnage loads. The length and tonnage required will, of course, vary with the drilling and equipment requirements of a particular job or undertaking.




Conventionally, links have been constructed as a unitary piece. Each pair of links are constructed to meet certain set tonnage requirements, such as being capable of supporting 500, 750, or 1000 tons. The links are also manufactured in certain given or set lengths such as 12 feet.




Consequently, certain lengths and tonnage capacities are often manufactured in greater abundance than other set lengths or tonnages. Depending on drilling demands in a particular drilling field, a shortage of certain lengths, tonnage capacities, or both may occur. At times a drilling site in a region may require links, for example, of twenty-one feet, while the primarily available links may be twelve feet in length.




Thus, it would be a benefit to have a method for construction and producing links of various length and tonnage capacities on relatively short notice.




GENERAL DESCRIPTION OF THE INVENTION




Pursuant to the foregoing, it may be regarded as an object of the present invention to overcome the deficiencies of and provide for improvements in the state of the prior art as described above and as may be known to those skilled in the art.




It is thus an object of the present invention to provide construction and producing links of various length and tonnage capacities on relatively short notice.




Still further objects may be recognized and become apparent upon consideration of the following specification, taken as a whole, in conjunction with the appended drawings and claims, wherein by way of illustration and example, an embodiment of the present invention is disclosed.




A multi-piece elevator link, which may be of variable length or capacity or both, is produced by cutting a unitary link into two or more parts and connecting different combinations of shanks and link ends to form the desired elevator link. Rotation of the link ends with respect to the shank may be prevented by a variety of means. For example, various threading, cross pins, locking mechanisms, interference fits, keys, hooks and the like may be employed. Various adapters may be employed between the shank and link ends to provide varying connections such as those produced by various threads, cross pins, ball-and-socket combinations, grooves and retaining rings, interference fits, keys, hooks and the like.




A method of dividing a unitary elevator link into two or more parts and providing the differing shank or link end or both is also set forth in the body of the specification, along with the use of the adapters and locking mechanisms.




To review the scope of the present invention, the variable length elevator link includes a shank, a first link end and a second link end.




The shank has a first collar end and a second collar end with each collar being adapted to connect to a link end. In one embodiment, each collar end may have internal threading to engage each second end of each link end having external threading.




Each link end has a first loop end forming an eye and a second end adapted for connecting to the first and second collar end of the shank. In one of the preferred embodiments, each link end has external threading to engage each shank collar having internal threading.




The method of the present invention allows one to select a shank of any desired length subject only to material strength limitations.




It has also been noted that when desired rotation may be prevented by means of the use of nuts and bolts or screws in the anti-rotation hole drilled through each shank collar engaged with a link end having corresponding holes drilled in its shank end.




There are many methods of connecting the components of the present invention. These techniques range from the easily assembled and disassembled to relatively permanent connections. Interference fits, ball-and-socket, grooves with lock or retaining rings, threads of single or multiple starts, and either straight or tapered pitch diameter, cross pins,jam or lock nuts, keys, and hooks are all alternative connections which may be employed in connection with the components of the present invention. Mechanisms such as nylon rings or inserts or both, anaerobic adhesives, or thread locking compounds may also be used.




It is to be noted that in one of the preferred embodiments a cross-drilled pin is located at or near the free end of the link connection where a hole is drilled through the male member at the end which is not stressed by the axial load. While the mating hole in the shank or adapter is therefore in the “high stress zone” of the shank or the adapter, these parts can be made of a sufficient cross-section or size so as to negate the effect on the part.




Some of the above alternatives may be used for direct connection of the link to the adaptor or to the center section shank, the limitation being the specific dimensions of the connecting means and the material available in the parts.




It is desirable to mate a threaded link end with one, and only one, threaded connection for its usable life, since no two threaded parts have the same characteristics, such as thread pitch. High loads on long, engaged lengths of such threads generally lead to some localized yielding. Changing mating parts would cause additional yielding, as two mating parts are deformed to match each other.




Each additional loading which is accompanied by yielding increases the chance of fatigue damage, which would render the part useless. In general, the connections made to the link ends are intended to be “married for life”.




One of the advantages of using an adapter between the shank and the link end is that the adapter can be mated to the link end instead of the shank itself. In other words, the adapter can be threaded as required to mate with the link end “for life”, with the connection at the opposite end of the adapter being designed and sized for interchanging shank center sections with each link end. For example, this approach could include different thread styles, larger connection size, or a different type of connection, all made possible by the fact that the adapter can be made as desired, and the interchangeable end of the adapter is not limited by the pre-existing size of the link. Once an adapter is fitted to the link ends, a center section can be fitted between the adapters of the opposing link ends.




By manufacturing different length shank center sections, one can produce an unlimited number of specific lengths.




Furthermore, the use of these adapters would allow interchangeable combinations, that is to say, assembling link ends of different nominal sizes or manufacturers or both into one assembly. It is sometimes the case that an elevator of 1000 ton capacity is selected for a string of only 500 tons, not because of the capacity of the elevator, but because of the slips which engage the pipe. Certain slips do less damage to the pipe being linked. However, the drilling rig may be equipped with only a 500 ton hook, which will not accept the larger 1000 ton links. In this case, the elevator links could be assembled with a 500 ton link end at the top in order to engage the hook, and a 1000 ton link end at the lower end in order to engage the elevator.




While one-piece forged links can be special ordered with different ends as described above, they are expensive and involve long delivery times. In general, such one-piece forged links can not be reconverted or reversed in orientation.




One set each of 500, 750, and 1000 ton links, equipped with adapters and a variety of combinations of center section shanks makes possible a large number of combinations and lengths.




Among the inventive features of the present invention are:




A first elevator link, having an elongated shank member comprising a connecting end and a first link end forming an aperture; and a second link having a first loop end forming an aperture and a second end adapted for connecting to the connecting end of the elongated shank member.




These features may also include a first link end which has a first loop end forming an aperture and a second end adapted for connecting to the shank and further means adapted for connecting such as internal threading in the connecting end of the elongated shank member; and external threading of the second end of the link end adapted for connecting to the connecting end of the elongated shank member.




Other means may also be adapted for connecting, such as a cross pin providing a connection between the connecting end of the elongated shank member and the link end.




A locking mechanism may be used in a connection between the elongated shank member and the link to prevent rotation of the link end in relation to the elongated shank member.




An adaptor with a first connecting end and a second connecting end; a link having a second end adapted for connecting being adapted to engage the first connecting end of the adapter; and the connecting end of the elongated shank member being adapted to engage the second connecting end of said adapter, also, is an inventive feature of the present invention, as are a ball-and-socket, grooves with retaining rings. threads of multiple start configurations. threads of tapered pitch diameter, cross pins, interference fits and means employing keys and hooks.




A further aspect of the present invention is the method of making a multi-piece elevator link, which may be of variable length or variable capacity or both, comprising in one way or another providing a unitary one piece elevator link comprising an elongated shank member, a first link end having a loop end forming an aperture, and a second link end having a loop end forming an aperture, said first and second link ends being at opposite ends of the elongated shank member, cutting the elongated shank member into two parts, providing at least one end of the elongated shank member with means adapted for connecting to an end link, and attaching a link end to the means adapted for connecting with the elongated shank member.




The means for connecting may be provided for both link ends, and an adapter may be placed between the elongated shank member and the link end and a means of connection may be provided for the elongated shank member and the link ends including means of connection through the adapter.




Rotation of the link ends with respect to the elongated shank member may be provided for. The end link and the adapter may be connected by means intended to mate them for their useful life. The connection to the elongated shank member allows for a change of the elongated shank member or the end link.




In short, multi-piece elevator links, which may be of variable length or capacity or both, may be produced by cutting a unitary link into two parts and connecting different combinations of shanks and link end to form the desired elevator link. Alternatively, the link ends may be manufactured with a loop end on one end and a connector on the other, the connector capable of connecting to the shank. This eliminates the need for a separate adapter by combining the adapter function with the link end.




Rotation of the link ends with respect to the shank may be prevented. Adapters may be employed between the shank and the link ends to provide varying connections.











BRIEF DESCRIPTION OF DRAWINGS




For a further understanding of the nature and objects of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawings, in which like elements are given the same or analogous reference numbers and wherein:





FIG. 1

is a top and side view of a unitary elevator link, in which

FIG. 1A

is the top view and

FIG. 1B

is the side view.





FIG. 2

is a top and side view of a unitary elevator link after division in accordance with the present invention, in which

FIG. 2A

is the top view and

FIG. 2B

is the side view.





FIG. 3

is a top view of the two ends of the elevator link as threaded and machined.





FIG. 4

is a top view of the two ends of the elevator link as inserted into a central shank.





FIG. 5

is a top view of the two end of an elevator link inserted in an adaptor for insertion into a central shank.





FIG. 6

shows a top view of four alternative forms of adaptors which may be employed in accordance with the present invention, in which

FIG. 6A

represents a retaining ring adaptor,

FIG. 6B

represents a multiple start and tapered pitch adaptor,

FIG. 6C

represents across pin adaptor and

FIG. 6D

represents a ball-and-socket adaptor.





FIG. 7

is a top view of a unitary elevator link.





FIG. 8

is a top view of a unitary elevator link.





FIG. 9

is a top view of a central shank.





FIG. 10

is a top view of an end link.











GENERAL DESCRIPTION AND EXEMPLARY MODE FOR CARRYING OUT THE INVENTION




For a further understanding of the nature, function, and objects of the present invention, reference should now be made to the following detailed description taken in conjunction with the accompanying drawings. Detailed descriptions of the preferred embodiments are provided herein, as well as, the best mode of carrying out and employing the present invention. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure, or manner. The practice of the present invention is illustrated by the following examples which are deemed illustrative of both the process taught by the present invention and of the product and article of manufacture yielded in accordance with the present invention.




In general, the present invention is implemented by beginning with a conventional unitary elevator link


10


as shown in

FIGS. 1 and 2

. The end eyes


15


are separated from a central shaft portion


22


and then recombined in various combinations as desired. The central shaft portion may, of course, be from a few inches in length to several feet long as may be desired.




A preferred method of implementing the present invention is best illustrated by reference to the appended figures beginning with FIG.


1


and

FIG. 2

which show a conventional unitary elevator link


10


produced by the method described in the background or any other well known or conventional method. The unitary elevator link


10


comprises a shank


22


and two ends generally referred to as the link ends


14


and


16


. Shank


22


is the long, narrow stalk or stem portion of bar material between the two ends


14


and


16


. As has been described in the background, the link ends


14


and


16


are conventionally manufactured with a void in each end. The voids or apertures are generally referred to as the eyes


15


by analogy with the eye of a needle although generally and in practice elevator links are many orders of magnitude larger than anything thought of as a conventional needle. The ends


14


and


16


of the elevator link


10


may differ slightly as a bottom end may have a slightly upturned end


18


as shown in

FIGS. 1B and 2B

. For purposes of the present invention the differences in the end


14


and


16


, if any, are not a crucial feature but, of course, will be take into account by those skilled in the art as the situation and desired results may warrant. In a like fashion the eyes


15


may be manufactured in slightly different geometries depending on the intended use. While the eyes are in general cylindrical holes they may in practice be manufactured as ovals or ellipses with slightly flattened elongate sides or in slightly pear shaped configurations depending on the intended applications.




In practicing the method of the present invention, the shank


22


is scribed as indicated at the marks


12


. The shank


22


is cut at the inner, most central inscriptions


12


and a tensile coupon or plug


20


is remove from the center section of the shank


22


as shown in FIG.


2


B. The tensile coupon or plug


20


may be used for testing the tensile strength of the shank


22


or for other tests of mechanical properties on the material such as will be familiar to those skilled in the mechanical arts. The unitary elevator link


10


has now been formed into a first link end


14


and a second link end


16


, with each link end


14


and


16


having an eye end forming the eyes


15


and a projecting shank portion or end of shank


22


material.




Turning to

FIG. 3

it will be seen that after severing the eyes


15


from the tensile coupon or plug


20


(see

FIG. 2

) the shank end may be threaded for attachment to one or another central shank member


22


. The reference numeral


32


indicates the reference location of the scribe mark


12


for machining and threading operations. Excess stock blocks or cylinders


30


may be used for chuck mounting and then removed following machining of the end. The projecting shank end


22


of each link end


14


and


16


may be threaded externally by the addition of threads


34


thereto. In addition, a relief radius


36


, sized appropriately to permit sealing or lubrication of the threads and typically a ¼ inch radius, may be circumscribed around the upper end of the threads


34


nearest the link ends


14


and


16


, as desired, and gripping of the ends


14


and


16


by fishing or gripping tools and the like.





FIG. 4

shows the simplest and a preferred mode of implementing the present invention as a multi-sectional elevator link


40


. In this embodiment the shank ends


22


of the link ends


14


,


16


are inserted directly into the central shank portion


44


. The link ends


14


and


16


each forming an eye


15


have been machined along their shank end


22


to provide external threads


34


as shown and described in connection with

FIG. 3. A

shank


44


which may be of varying dimensions as suggested at


45


, in which the shank bar


44


may be either narrowed in the region


45


or enlarged in the region


45


. In any case the end collar regions


54


of shank


44


must be of sufficient diameter to accommodate the shank end


22


of link ends


14


and


16


. A cavity is bored longitudinally along the center line axis of shank


44


of sufficient diameter and depth to accommodate the shank end


22


of elevator link ends


14


and


16


. In addition the cavity is threaded with internal threads to engage threads


34


which are external to shank


22


which is threaded into the shank


44


to a depth to place the threads


34


slightly inside the collar ends


54


as shown at


52


.




To prevent rotation of the link ends


14


and


16


within the collars


54


, a rotational restraining device


58


is provided. The shaft of each shank end


22


has been bored with a transverse hole


56


along the center line and axis of shank end


22


and perpendicular thereto and so positioned as to lie in the plane of the link heads


14


and


16


, respectively.




Matching and mating holes


42


are bored in the collar section


54


of shank


44


and a suitably sized bolt


46


is inserted through holes


42


and


56


to permit bolt


46


to pass through and be secured by nut


48


, which may be further secured to the bolt


46


as indicated at


50


to prevent tampering such as by welding.




By selecting the desired length shank, of length S, the effective length of the elevator link, L, may be altered. By selecting various link ends


14


and


16


and various size shanks


44


the tonnage capacity may also be altered.




From these various combinations a multi sectional elevator link


40


may be fashioned of the desired length and of the desired tonnage capacity.




As shown in

FIG. 5

, the above described approach to tailoring the length and tonnage capacity of elevator links may be taken a step further in the particularly preferred embodiment shown.




In the approach of

FIG. 5

an adaptor


64


is employed. The adaptor


64


may be of several different forms as will be discussed in greater detail below with regard to FIG.


6


. The elevator link ends


14


and


16


with eyes


15


and with projecting shank ends


22


are prepared and threaded as described above in connection with FIG.


3


. However, instead of being inserted into shank


44


directly, the projecting shank


22


is inserted into an adaptor


64


. The adaptor


64


makes possible the employment of a wide variety of varying size and types of threading and size and strength of shank


44


.




Both standard and non-standard sizes and threads may be employed. In addition the use of an adaptor


64


may allow for additional degrees of freedom of motion for the link ends


14


and


16


as will be seen in particular with the embodiments of

FIGS. 6A and 6D

.




As shown most directly in

FIG. 5

the link end


14


and


16


may be threaded into the adaptor


64


by insertion into an internally threaded cavity


70


. Various combinations of standard and non-standard threads of varying pitch and dimension may be employed to produce locked or cross threads which effectively secure the link end


14


or


16


within the adaptor


64


for the life of the parts. The adaptor


64


may itself have external threads


72


on its other end for insertion into a cavity


74


in the collar portion


54


of the ends of shank


44


. Internal threads


62


may be provided in the cavity


74


on one or both of the ends of shank


44


.




Among the many alternative adaptors are those shown in FIG.


6


.





FIG. 6A

shows link end


14


with eye


15


threaded in cavity


70


of adaptor


64


being provided with groove


82


and tapered end


80


. The tapered end


80


is inserted into cavity


84


in shank


44


and retained by the action of a retaining ring in groove


86


.





FIG. 6B

shows link end


14


with eye


15


threaded in cavity


70


of adaptor


64


. Adaptor


64


may be provided with inclined or tapered multiple start threads


90


for mating with a tapered pitch threaded diameter


92


on the end of shank


44


.





FIG. 6C

shows link end


14


with eye


15


threaded in cavity


70


of adaptor


64


. The adaptor


64


has a drilled hole


98


and tapered end


102


for insertion into a matching cavity


94


in shank


44


which has been drilled with matching holes


96


. A nut and bolt combination as described above with reference to

FIG. 4

may be used to prevent rotation as well as for fastening the link end in place, if desired.





FIG. 6D

shows link end


14


with eye


15


threaded into cavity


70


of adaptor


64


. A tapered segment


106


of the adaptor connects to ball


108


which is inserted into a ball cavity or socket


112


through tapered section


110


in the end of shank


44


.




It is to be noted that the link end


14


are provided with additional degrees of rotational freedom as shown in FIG.


6


A and with a 360° cone of freedom of motion, as well as, with rotational freedom in the embodiment of FIG.


6


D. The other embodiments provide a constraint on the freedom of motion for situations in which it is desired.




To review the scope of the present invention, the variable length elevator link includes a shank, a first link end and a second link end.




The shank has a first collar end and a second collar end with each collar being adapted to connect to a link end. In one embodiment each collar end may have internal threading to engage each second end of each link end having external threading.




Each link end has a first loop end forming an eye and a second end adapted for connecting to the first and second collar end of the shank. In one of the preferred embodiments each link end has external threading to engage each shank collar having internal threading.




It is to be noted that in one of the preferred embodiments a cross-drilled pin is located at or near the free end of the link connection where a hole is drilled through the male member at the end which is not stressed by the axial load. While the mating hole in the shank or adapter is therefore in the “high stress zone” of the shank or the adapter, these parts can be made sufficient cross-section or size so as to negate the effect on the part.




As taught by the specific examples discussed above there are many methods of connecting the components of the present invention. These techniques may range from the easily assembled and disassembled to relatively permanent connections. Interference fits, ball-and-socket, grooves with lock or retaining rings, threads of single or multiple start and either straight or tapered pitch diameter, cross pins, jam or lock nuts, keys, and hooks are all alternative connections which may be employed in connection with the components of the present invention. Additional mechanisms may be present to further secure the connections such as nylon rings or inserts or both, anaerobic adhesives, or thread locking compounds.




Some of the above alternatives may be used for direct connection of the link to the adaptor or to the center section shank, the limitation being the specific dimensions of the connecting means and the material available in the parts.




It is desirable to mate a threaded link end with one, and only one, threaded connection for its usable life, since no two threaded parts have the same characteristics, such as thread pitch. High loads on long, engaged lengths of such threads generally lead to some localized yielding. Changing mating parts would cause additional yielding, as two mating parts are deformed to match each other. Each additional loading which is accompanied by yielding increases the chance of fatigue damage, which would render the part useless. In general, the connections made to the link ends are intended to be “married for life”.




One of the advantages of using an adapter between the shank and the link end is that the adapter can be mated to the link end instead of the shank itself. In other words, the adapter can be threaded as required to mate with the link end “for life”, with the connection at the opposite end of the adapter being designed and sized for interchanging shank center sections with each link end. For example, this approach could include different thread styles, larger connection size, or a different type of connection, all made possible by the fact that the adapter can be made as desired, and the interchangeable end of the adapter is not limited by the pre-existing size of the link. Once an adapter is fitted to the link ends, a center section can be fitted between the adapters of the opposing link ends. By manufacturing different length shank center sections, one can produce an unlimited number of specific lengths.




Furthermore, the use of these adapters would allow interchangeable combinations, that is to say, assembling link ends of different nominal sizes or manufacturers or both into one assembly. It is sometimes the case that an elevator of 1000 ton capacity is selected for a string of only 500 tons, not because of the capacity of the elevator, but because of the slips which engage the pipe. Certain slips do less damage to the pipe being lifted. However, the drilling rig may be equipped with only a 500 ton hook, which will not accept the larger 1000 ton links. In this case, the elevator links could be assembled with a 500 ton link end at the top in order to engage the hook, and a 1000 ton link end at the lower end in order to engage the elevator.




While one-piece forged links can be special ordered with different ends as described above, they are expensive and involve long delivery times. In general, such one-piece forged links can not be reconverted or reversed in orientation.




In the operation of the preferred embodiment, the process of creating the present invention may begin in one of a number of ways. For example, a single unitary forged unit may be severed in two places to yield two ends


22


and a central plug portion


20


as shown in FIG.


7


. These component parts may be joined with other similarly severed components to produce a link having the desired length and load capacity,




Another approach which may be employed independently or in combination with the above process is to sever a single unitary forged unit at a single point as shown in

FIG. 8

in which one eye


15


and central plug


20


remain as a single unit and a separated eye


15


and shank


22


unit is produced to be employed in other combinations with other length shanks or other rated load units.




Finally as shown in

FIGS. 9 and 10

individual central shanks


22


, central plugs


20


, and individual eyes


15


may be produced to be employed in any number of possible desired combinations.




One set each of 500, 750, and 1000 ton links, equipped with adapters and a variety of combinations of center section shanks makes possible a large number of combinations and lengths.




As has been described herein these various combinations and the ability to produce variable length and capacity links is a result of the application of the inventive concepts of the present invention. For example, a variable length or strength multi-piece elevator link


10


may be produced by providing an elongated shank


22


and a link end having a loop end forming an aperture and eye member at one end of the elongated shank member and then providing a link end forming an aperture and eye member for attachment to the opposite end of the elongated central shank member to produce an elevator link of the desired length or load capacity or both by attaching at least one link end having a loop end forming an aperture and eye member to said central shank




At least one of the link ends having a loop end forming an aperture and eye member may be attached to the elongated central shank member by means of an adaptor. Of course it is possible depending upon the desired end for one of the link ends forming an aperture and eye member to be and remain a unitary part of the elongated central shank member. The cutting each of several unitary one piece elevator links into at least two parts to form two or more link ends each having a different capacity from the other and two or more elongated central shank members each being of a different length or capacity from another elongated central shank member formed and produced in the same manner as defined herein; followed by attaching at least one of the link ends to one of the elongated central shank members provides a means and a method permitting the formation of a wide variety of variable length and/or capacity elevator links within or without the use of an adaptor between the link ends and the elongated central shank member.




The adaptor may provide means to lengthen or shorten the effective length of the total elevator link and/or to permit rotation of the link end with its loop end forming an aperture and eye member around the central longitudinal axis of the elongated central shank member. The adaptor may include locking means which restrict or prevent rotation of the link end around the central longitudinal axis of the elongated central shank member. Additionally, the link ends may be manufactured integrally with the adapter in a single forging when the invention is applied during the initial manufacture.




It is noted that the embodiment of the elevator link described herein in detail for exemplary purposes is, of course, subject to many different variations in structure, design, application and methodology. Because many varying and different embodiments may be made within the scope of the inventive concepts herein taught, and because many modifications may be made in the embodiment herein detailed in accordance with the descriptive requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense. It will be understood in view of the instant disclosure, that numerous variations on the invention are now enabled to those skilled in the art. Many of the variations reside within the scope of the present teachings. It is not intended to limit the scope of the invention to the particular forms set forth, but on the contrary it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the teachings of the present invention. Accordingly, the invention is to be broadly construed and is to be limited only by the spirit and scope of the claims appended hereto.



Claims
  • 1. An elevator link, comprising:an elongated shank member comprising a first connecting end and a first link end having an aperture therethrough, the first link end capable of supporting a first predetermined tonnage; and a second link having a second connecting end and a first loop end having an aperture therethrough, the second link capable of supporting a second predetermined tonnage; wherein the second connecting end of the second link is adapted to connect to the first connecting end of the elongated shank member; and the first predetermined tonnage is different than the second predetermined tonnage.
  • 2. The elevator link of claim 1 wherein the first connecting end of the elongated shank member and the second end of the second link further comprise a set of complementary threads whereby the set of complementary threads matingly engage the elongated shank member to the second link.
  • 3. The elevator link of claim 1 further comprising at least one cross pin in connection between the first connecting end of the elongated shank member and the second connecting end of the second link.
  • 4. The elevator link of claim 1 further comprising a locking mechanism disposed intermediate the elongated shank member and the second link to prevent rotation of the second connecting end of the second link in relation to the elongated shank member.
  • 5. The elevator link of claim 1 further comprising an adapter, the adapter comprising a first connecting end and a second connecting end wherein the second connecting end of the second link is adapted to engage the first connecting end of the adapter and the first connecting end of the elongated shank member is adapted to engage the second connecting end of the adapter.
  • 6. The elevator link of claim 5 wherein the adapter and the second link comprise a single forged unit.
  • 7. The elevator link of claim 5 wherein the first connecting end of the adapter and the second connecting end of the second link comprise a ball-and-socket.
  • 8. The elevator link of claim 5 wherein the second connecting end of the adapter and the first connecting end of the elongated shank member comprise a ball-and-socket.
  • 9. The elevator link of claim 5 wherein the first connecting end of the adapter and the second connecting end of the second link comprise at least one groove and at least one retaining ring.
  • 10. The elevator link of claim 5 wherein the second connecting end of the adapter and the first connecting end of the elongated shank member comprise at least one groove and at least one retaining ring.
  • 11. The elevator link of claim 5 wherein the first connecting end of the adapter and the second connecting end of the second link comprise threads of multiple start configurations.
  • 12. The elevator link of claim 5 wherein the second connecting end of the adapter and the first connecting end of the elongated shank member comprise threads of multiple start configurations.
  • 13. The elevator link of claim 5 wherein the first connecting end of the adapter and the second connecting end of the second link comprise threads of tapered pitch diameter.
  • 14. The elevator link of claim 5 wherein the second connecting end of the adapter and the first connecting end of the elongated shank member comprise threads of tapered pitch diameter.
  • 15. The elevator link of claim 5 wherein the first connecting end of the adapter and the second connecting end of the second link comprise at least one cross pin.
  • 16. The elevator link of claim 5 wherein the second connecting end of the adapter and the first connecting end of the elongated shank member comprise at least one cross pin.
  • 17. The elevator link of claim 5 wherein the first connecting end of the adapter and the second connecting end of the second link comprise interference fits.
  • 18. The elevator link of claim 5 wherein the second connecting end of the adapter and the first connecting end of the elongated shank member comprise interference fits.
  • 19. The elevator link of claim 5 wherein the first connecting end of the adapter and the second connecting end of the second link comprise at least one key.
  • 20. The elevator link of claim 5 wherein the second connecting end of the adapter and the first connecting end of the elongated shank member comprise at least one key.
  • 21. The elevator link of claim 5 wherein the first connecting end of the adapter and the second connecting end of the second link comprise at least one hook.
  • 22. The elevator link of claim 5 wherein the second connecting end of the adapter and the first connecting end of the elongated shank member comprise at least one hook.
RELATED APPLICATIONS

The present invention claims priority from U.S. of America Provisional Patent Application 60/131,998 filed Apr. 30, 1999 for “Variable Length/Capacity Elevator Links”.

US Referenced Citations (5)
Number Name Date Kind
3777046 Schiavone Dec 1973 A
3996737 Burstall Dec 1976 A
4421447 Gudgel et al. Dec 1983 A
5529316 Mattila Jun 1996 A
5906450 Ng May 1999 A
Provisional Applications (1)
Number Date Country
60/131998 Apr 1999 US