US3067570A

US3067570A - Rope sling and process for forming the sling

Info

Publication number: US3067570A
Application number: US6062A
Authority: US
Inventors: Joseph V Nischan
Original assignee: Impact Extrusions Inc
Current assignee: Impact Extrusions Inc
Priority date: 1960-02-01
Filing date: 1960-02-01
Publication date: 1962-12-11
Anticipated expiration: 1979-12-11

Description

Dec. 11, 1962 J. v. NlscHAN ROPE SLING AND PROCESS FOR FORMING THE SLING Fil-ed Feb. l, 1960 /ff/ y///////////// "4942 y/y Y 4/ l 77er:

2 Sheets-Sheet 1 INVENTOR.

J. V. NlSCHAN Dec. l1, 1962 3,067,570

ROPE BLING AND PRocEss FOR FORMING THE sLING 2 Sheets-Sheet 2 Filed Feb. l, 1960 @Je z/z ment ae@ 3,067,570 Patented Dec. 11, 1962 3,067,570 ROPE SLING AND PROCESS FOR FORMING THE SLING Joseph V. Nischan, Calumet City, Ill., assignor to Impact Extrusions, Incorporated, Valparaiso, Ind., a corporation of Indiana Filed Feb. 1, 1960, Ser. No. 6,062 7 Claims. (Cl. 57-142) This invention relates to a rope sling and more particularly pertains to a novel sleeve construction utilized in the formation thereof. This application is a continuationin-part of my co-pending application Serial No. 795,826, which was filed February 26, 1959 and entitled Rope Sling, now abandoned.

Rope slings are in widespread use and serve a multitude of purposes in industry. All slings in use are rated as to the particular loads which they will sustain wi-thout breakdown. In accordance with this invention it has been found that by appropriate formation of the ferrule or sleeve which locks the ends of the sling eye to the main rope, the strength of the sling may be very materially increased.

It is an object of this invention, therefore, to provide an improved rope sling which possesses strength superior to that of other sling constructions presently in use which are comparable in size and which employ conventional sleeve constructions.

It is another object of this invention to provide an improved rope sling which uses sling components and manufacturing apparatus well known in the art; only the sleeve of the provided sling is altered in construction.

It is yet another object of this invention to provide an improved rope sling which employs a ferrule or sleeve which engages the main rope and loop 'or eye-forming portions of such rope in a firm and secure manner previously unattained.

The above and other objects of this invention will become more apparent from the following description when read in the light of the accompanying drawing and appended claims.

In one embodiment of the subject sling a rope, preferably formed of wire strands, is provided having an eye or loop defining at least one thereof. The eye is formed by separating or unlaying one end of the rope into two groups of strands. The strands are bent and intertwined to form a loop which defines the eye of the sling. The terminal portions of the eye-forming strands are then disposed over the main unseparated portion of the rope disposed adjacent the eye. A ferrule having two concentric passageways with dissimilar diameters is then disposed about the strand terminal portions and swaged into tight engagement with both the main rope portion and the terminal portions of the eye-forming strands as will hereinafter be disclosed in greater detail.

For a more complete understanding of this invention reference will now be made to the drawing wherein:

FIGURE l is a fragmentary elevational view of a rope sling formed in accordance with the teachings of this invention;

FIG. 2 is a fragmentary elevational view of an end portion of a rope member preliminarily to forming an eye portion at one end thereof;

FIG. 3 is a fragmentary elevational view of a rope end portion illustrating an eye partially formed at one end thereof.

FIG. 4 is a fragmentary elevational vieW- of a rope portion illustrating a formed eye at one end thereof with a sleeve in place prior to a swaging or pressing step;

FIG. 5 is a fragmentary elevational view partly in secsleeve is shown in section;

FIG. 6 is a sectional view taken in line 6-6 of FIG. 5.

FIG. 7 is an elevational view of a modified ferrule construction formed in accordance with the teaching of this invention;

FIG. 8 is a diametrical sectional view of the ferrule illustrated in FIG. 7;

FIG. 9 is a fragmentary elevational View of the end of a Wire rope in which portions thereof have been unlayed prior to forming an eye therein, and

FIG. l0 is a fragmentary elevational view partly in section similar to FIG. 5 illustrating a completed rope sling-eye employing the ferrule illustrated in FIGS. 7 and 8.

Referring now more particularly to FIG. l, rope sling 10 is illustrated. The sling is seen to comprise a main rope por-tion 12 which communicates with an eye or loop portion 14 composed of rope of the same diameter. A ferrule or sleeve 18 is situated at the juncture of the main rope 12 and the loop portion 14.

Method of Eye Formation The eye 14 of FIG. l may be formed in the following.

manner: An end portion of the main rope 12 is unlayed or divided into two groups of strands 12a and 12b. Each of said groups preferably has the same number of strands. It will be noted from FIG. 2 that the main rope 12 is composed of siX individual strands 12C which are en- .twined about each other to form the rope. In the illustrated wire rope sling each strand 12C is composed of` individual wires twisted together.

The ytwo groups of strands 12a and 12b are bent into a looped configuration, each group being bent toward the opposing group. As the two groups are bent the strands thereof are entwined -so as to define the eye portion 14 which is formed from the same number of strands 12C as the main rope portion 12. The terminal portions of each eye-forming strand group terminate about that portion of the main rope 12 which is contiguous with the rope eye 14.

FIG. 4 illustrates a rope member after Ithe eye 14 has been formed from split end portions of the main rope 12. 'Ihe next step in the rope formation is the securing of the end portions of the eye-forming strands of the main rope portion so that the rope eye 14 will resist any stresses exerted thereon tending to separate the end por-tions of the eye from the main rope portion. The means for securing the end portions of the eye-forming strands to the main ropes comprises sleeve 18, illustrated most clearly in FIG. 1.

Sleeve Construction The use of sleeves or ferrules for purposes of retaining the end portions of a rope loop to a main rope portion is Well known. Generally, the hollow sleeve of the prior art has a cylindrical configuration tapered both internally and externally at one end portion. The latter sleeve tapers are for purposes of facilitating sling use in the normal course of employment of the same and in no way assist interlocking of the -various sling components. The terminus of the tapered end portion is disposed over the main rope portion and the non-tapered portion of the sleeve is disposed over the end portions of the eye-forming strands arranged over the main rope. The sleeve is designed to -readily slip over the main rope. and facilitate connection of the main rope with the eye-forming strands. After the sleeve is is the latter position swaging dies press the periphery of the sleeve into tight engagement with the eye-forming strands disposed within the central passageway of the sleeve. j

It is thus apparent that in employing sleeves of the prior art the only firm engagementV or secure interlocking of the sleeve is with the terminal portions of the eyeforming strands of the rope and not with the exposed periphery of the main rope since the tapered portion of the sleeve does not rmly engage the main rope. As a result, such slings are subject to comparatively easy deterioration. Forces exerted on the eye por-tion of the sling tending to move the eye-forming strands relative to the main rope readily permit slippage between the eyeforming strands and the underlying main rope since the sleeve is firmly secured to the eye-forming strands only. Thus, the sleeve and strands would move relative to the underlying main cable.

In accordance with the subject invention sleeve 18 (see FIG. 4) is employed which has two concentric passageways 20 and 22 of dissimilar diameter. Each diameter, however, is substantially uniform; there is preferably no taper in either passageway. It will be noted that the upper end portion of the sleeve 18, corresponding to the tapered portion of the previously employed sleeves known in the art, does not have a tapered passageway but rather employs a passageway 2t) which is of slightly greater diameter than that of the main rope portion about which it is disposed. This passageway communicates with the passageway4 22 which is adapted to encompass the terminal portions of the rope strand groups 12a and 12b, as well as a portion of the main rope 12 underlying the strands. Passageway 22 is greater in length than 29 being of the order of three or four times greater. These ratios are given by way of illustration only, however, and are not critical. Since the portion of the sling which passageway 22 overlies is composed of twelve strands, passageway 22 is7 of course, of a greater diameter than passageway 20. Passageway 22, however, need not be twice as large as passageway 26 since terminal portions of the strands 12C lie in the valleys of the rope portion 12, thus the length of the sling portion defined by the eye-forming strands and main rope 12 need not be twice as great in diameter as the main rope 12.

Following the assembly of the rope and sleeve in the manner illustrated in FIG. 4, swaging dies are actuated toward the center of the sleeve pressing the sleeve inwardly into the configuration illustrated in FIG. 5.

Since the external diameters of the two passageways are substantially the same, both passageway surfaces will be pressed inwardly unlike the prior art sleeves.

It will be noted from FIG. 5 that the internal surface of' the sleeve y18 defining the passageway 2t) securely engages a peripheral length of the main rope 12 and the internal surface of the sleeve 18 defining the passageway 22 securely engages the surfaces of the terminal portions of the eye-defining strands making up the two groups 12a and 12b. The sectional view of FIG. 6 illustrates the tight secure engagement between the sleeve and rope strand members.

It is apparent that the material from which the rope is constructed is preferably metal for purposes of being suitable for the many industrial uses in which strength is desired. The material of composition from which the sleeve is made is also preferably of metal, aluminum being particularly well adapted for this purpose.

The above described sling possesses great strength. The sleeve is fixedly secured not only to eye-defining portions of the rope but, in addition, is ixedly and securely attached to a peripheral portion of the main rope or cable. Heretofore, the sleeve had only been attached to the eye-defining portions of the sling and, as a result, such sling would break down rather easily in comparison with the sling provided by this invention.

The provided sling does not require any additional or unique apparatus of manufacture. It only requires that apparatus which is well known and which has previously i been used in this art.

M odifed F errule Construction ,It apparent that a number of modified ferrule and sling eye constructions may be fabricated similar to thesling eye and ferrule above described, which will remain. within the ambit of the broad inventive concepts hereinf disclosed. For instance, in FIGS. 7 and 8 elevational and sectional views respectively are illustrated of a fer-- rule construction which differs from the ferrule 18 above described. Ferrule 30 of FIGS. 7 and 8 is provided with a passageway 32 which is in concentric alignment and communication with a larger ferrule passageway 34. The latter passageway is approximately three times as long as passageway 32 and somewhat larger in diameter to accommodate a number of rope strand terminal ends which will be disposed therein and not in passageway 32.

An outer peripheral bevel 36 is formed in the distal end portion of ferrule 30 in which passageway 32 is disposed. Disposed in the opposite end portion of ferrule 34B is an inner peripheral bevel 48 which facilitates insertion of wire rope ends into the concentric passage-

A ways

32 and 34 in the normal course of sling eye forma-- tion. This bevel is not found in ferrule 18.

Flemish Splice Eye In FG. 9 a fragment of a wire rope is illustrated preliminary to the formation of a loop or eye by means of a so-called Farmers or Flemish splice. The latter splice is well known in the art. In the formation of a Flemish splice, the end portion of a multiple strand wire rope is unravelled to produce two helical spiral groups of strands, such as illustrated in FIG. 9. It will be noted from FiG. 9 that rope l2 has the six strands of the end portion thereof divided into two

groups

44 and 46. Because of the inherent rigidity of the metal from which the strands of the wire rope are formed, the two series of

strands

44 and 46 retain their helical configuration into which the strand groups were formed in the course of rope formation although unravelled.

To form the Flemish splice, the two groups of strands are looped in opposite directions to form an eye, the oppositely extending strands being intertwined, utilizing the same helical formation previously imparted to the strands in the course of intertwining for purposes of forming an eye. IIt is seen, therefore, that because of the helical configuration into which the rope strands were formed. in the course of rope-making, re-weaving the two separated groups of strands into an integral eye configuration is a simple task and little effort need be expended in forcing the strands into interwoven engagement with each other.

The length of the strand ends originally interwoven and the length of the eye formed from such strands should be such that at the completion of the eye formation a predetermined length, equal to the length of the ferrule larger-diameter passageway, should be disposed along the main rope extending from the juncture or throat of the sling eye, A ferrule such as ferrule 38 may then be moved over the main rope portion 42 with the smaller passageway 32 extending away from the eye-throat or juncture with the main rope and a relationship between the ferrule and sling eye formed similar to that illustrated between the ferrule 18 and rope 12 in FIG. 4. It is apparent that the terminal ends of the wire strands, which are disposed along the side of the main rope, function as a positive stop means upon engagement of internal shoulder 48 of ferrule 30, thereby predeterminately disposing the ferrule in proper relationship with the sling eye components. As previously mentioned, the beveled inner edge 4t) of ferrule 30 will facilitate movement of eye strand terminal portions 50 illustrated in FIG. 10 into the ferrule larger passageway 34.

Ferrue Swagng Operation Following the arrangement of the ferrule over the end portions of the rope eye-forming strands, so that the end portions of the strands abut against internal shoulder 48 of ferrule 30, compression is exerted on the outer periphery of ferrule 30 so that the inner peripheries of

passageways

34 and 32 of ferrule 30, are pressed into tight gripping engagement with the external periphery of the wire strand terminal portions, from which an eye 52 fragmentarily illustrated in FIGS. 9 and 10 has been formed, and the periphery of main rope 42 respectively.

The terminal portions 50 of the eye-forming rope strands in the course of the die action which inwardly compresses the periphery of the ferrule 30, tend to assume a somewhat random arrangement within the cornpressed ferrule as the metal'of the ferrule becomes ernbedded in the valleys disposed between the various wire strands, as well as the fine valleys of the wires which make up each individual strand. As a result of this metal flow, it is apparent that a tight gripping engagement will exist between the ferrule and portions of the wire rope disposed therein in the manner illustrated in FIG. 10.

It will also be noted from FIG. 10 that because of the stop action exerted by internal shoulder 48 of ferrule 3i?, passageway 34 only of ferrule 30 will have disposed therein terminal portions 50 of the wire strands which were utilized in the formation of eye 52 by means of the Flemish splice. Passageway 32 of ferrule Sti` will have disposed therein the main rope 42 alone; no terminal strand portion 50 will be within passageway 32. As a result of the swaging action, therefore, a relationship such as illustrated in FIG. 10 Will exist between the ferrule and the various portions of the wire rope which go to make up the sling construction. The ferrule passageway 32 will be pressed into tight gripping engagement with the outer periphery of the strands employed in making up the main rope itself. The inner periphery of ferrule passageway 34 will engage in tight gripping engagement terminal strand portions 50 as previously mentioned. Because of the pressures exerted on the periphery of ferrule 30 the ferrule will lengthen slightly in addition to having inner peripheral portions flow into valleys and interstices between strands and wires of the individual strands. The ferrule eye connection of FIG. 10 is of great strength and will exceed the strength of the rope itself so that deterioration of a sling eye employing such a ferrule connection will not occur at the juncture between the eye main rope, but rather will occur somewhere within the body of the rope itself when the strength thereof is exceeded.

Referring to FIG. 9, it will be noted that a core 51 is illustrated which terminates substantially at the throat or jucture between the main rope and the two groups of

strands

44 and 46 which are to be woven into the form of a completed eye. The core 51 may have a short length cut therefrom as illustrated or may be looped to curve around in one of the two groups of

strands

44 and 46, but in any event it is best not to allow the core to enter ferrule passageway 34 in the form of a terminal end, such as the strand ends Silas it might interfere with the best disposition of the strands for gripping action by the sleeve. However, although preferable to cut the core piece, such as member 51, prior to entry of the eyev forming strands into the ferrule, it is not essential.

It should be further noted that although illustrated eye member 52, which is formed utilizing a Farmers or Flemish splice, employs strands woven from two groups of equal numbers that is, from the two

groups

44 and 46, each of which contains three strands, the eye formations of this invention may be formed from ropes employing odd numbers of strands, such as 5 strands or 7 strands. For obvious reasons of balance, however, it is desired that the two groups of helical strands formed in the formation of a sling eye by means of a Farmers or Flemish splice be of equal numbers.

Ferrule Grpping Action The novel ferrule of this invention enables a strong eye to be formed in a sling which, as above mentioned, will have a strength exceeding the strength of the rope itself. The presence of the ferrule portion defining the smaller passageway 32 therein enables the latter portion of the ferrule to be anchored firmly to the main rope 42 in the manner illustrated in FIG. 10. As a result of the firm anchor of the ferrule on the main rope body the metal of that portion of the ferrule ows inwardly around the exposed surface portions of the rope strands and has less tendency to now longitudinally. This inward flow results in a firm gripping of that portion of the ferrule to the main rope and of the remaining portion of the ferrule to the terminal portions of the wire strands employed forming the sling eye.

Ferrule Material of Composition It is desired, as above mentioned, that the ferrule metal flow into interstices between the wire strands, as well as the valleys formed by the wires of the individual strands. It has been found that aluminum alloy ferrules function satisfactorily for purposes of this invention. More specifically, aluminum alloys, such as alloy bearing the identifying No. 30034:, have been found particularly well adapted for serving the purposes of this invention. The latter alloy comprises approximately 98.8% pure aluminum and approximately 1.2% manganese. Another aluminum alloy found satisfactory for purposes of this invention is that bearing the identifying No. 6063F, which contains .10 copper, .35% iron, .45 to .90% magnesium, .1% zinc, .1% titanium, .2O to .6% silicon, .1% manganese, .10% chromium and the remainder aluminum. The material of composition for the ferrules of this invention should be sufficiently strong so as to tightly engage the rope strands and should be sufficiently ductile so as to flow into the interstices of the contacted strands without cracking to a substantial extent. Also, the material of composition of the ferrule should not be so hard as to damage seriously the wire strands which they engage when subjected to the pressure required to unite the parts as before described.

In order to assure a firm anchoring of a ferrule such as ferrule 30 to the main rope, it is desired that the length of the ferrule passageway traversed by the main rope be equal to a substantial portion of the rope diam'- eter engaged; preferably the length of the passageway should approximate the diameter of the rope engaged thereby. The iirrn' anchoring of the ferrule to the main rope limits longitudinal movement of the main rope relative to the eye-forming strand terminal end portions and the firm engagement between the strand terminal portions and the internal periphery of the larger ferrule passageway prevents disengagement of any of the rope ends from the ferrule.

In addition to strength, the illustrated ferrule 30 possesses a number of other handling advantages. As above mentioned, bevel 40 facilitates movement of the ferrule over the strand terminal portions 50 in the preliminary course of assembly prior to a swaging operation. Peripheral relieved ring portion 38 formed in passageway portion 32 following the swaging operation (see FIG. 10) allows freedom of movement of the main rope relative to the end portion of passageway 32, which is desirable in the normal course of using the eye construction. It has been found that good results are obtained when the passageway 34 is several times the length of passageway 32 and that somewhat better results obtain -When the length of passageway 34 is of the order of four times that ofthe passageway 32.

The illustrated ferrule 30 possesses substantially a uniform external diameter throughout its entire length, however it may be possible to design a ferrule having internal passageways of different diameter and also having external diameters which diler somewhat. Obviously, the presence of different external diameters in a single ferrule member will lead to problems in swaging die formation, as well as problems in the course of the actual formation of the ferrule itself. The presence of a single outside diameter which is substantially uniform is desired in the swaging operation above described for securing the ferrule to the rope portions since die costs and other problems, as well as swaging problems, are maintained at a minimum.

In view of the many modifications which are possible employing the inventive concepts above described, it is intended that this invention be limited only by the scope of the appended claims.

I claim:

1. A ferrule for use in forming a sling eye in conjunction with a rope, said ferrule comprising integral first and second portions; said first portion having an opening therein and extending therethrough for receiving a portion of said rope; said second ferrule portion having an opening extending therethrough, the crosssectional area of which is greater than that of the opening in the first ferrule portion, the opening in said first ferrule portion being of a length which is at least equal to one-half the greatest cross-sectional dimension of the rope with which the ferrule is to be used whereby innerperipheral portions of said first ferrule portion may be compressed into engagement with a length of rope sufficient to firmly anchor said ferrule to said rope in the normal course of ferrule use, said ferrule first and second portions having a substantially uniform external diameter.

2. In a process for forming a rope sling which employs an eye formed by splitting the end of a main rope into a plurality of parts and reforming the split ends into an eye, the terminal portions of which are disposed about a main rope portion adjacent said formed eye, the improvement comprising placing a ferrule about said split end terminal portions and the portion of said main rope adjacent thereto and locking said ferrule to both said latter main rope portion and said terminal portions by inwardly pressing the external periphery of said ferrule.

3. A ferrule for use in forming a sling from a rope comprising a cylinder having a first substantially cylindrical hollowedout portion of substantially uniform internal diameter and of sufficiently large dimensions whereby the rope may be received in said first ferrule portion and compressed into engagement with a length of rope sufficient to firmly anchor said ferrule thereto, a second concentric substantially cylindrical hollowed-out portion of substantially uniform internal diameter larger than said first internal diameter and in communication with said first hollowed-out portion, the first and second portions of said ferrule being of substantially uniform external diameter throughout the major portion of their length.

4. The ferrule as recited in claim 3 in which said second hollowed-out portion has a length about three to four times as great as said first hollowedout portion.

5. A rope sling comprising a main section of rope composed of strands and having an eye defining one end thereof, said eye being formed from split ends of said rope intertwined to form such eye, the terminal portions of said split ends terminating over a portion of said rope main section adjacent the juncture thereof with said eye, and ferrule means for clamping said terminal ends of said rope split ends to said main rope, said ferrule means having a first hollowed-out annular portion in which the external exposed surfaces of the strands of the main section of the rope are embedded thereby securely interlocking the main section of the rope with said first hollowed-out annular portion, said ferrule means having a second hollowed-out annular portion, integrally formed with said first portion in which the external exposed surfaces of the terminal ends of said rope split ends are embedded, thereby securely interlocking said terminal ends of said rope with said second holloWed-out annular portion.

6. In a process for forming a rope sling, the steps comprising splitting the end of a main rope into equal parts, entwining said split ends to form an eye, disposing the terminal portions of said split ends about the main rope portion adjacent said eye, placing a ferrule about said split ends terminal portions and a portion of said main rope adjacent said split ends and locking said ferrule to both said latter main rope portion and said split ends by inwardly pressing the external periphery of said ferrule sufficiently to cause the exposed external surface of the strands of the rope main section and split ends to become embedded in the body of .said ferrule.

7. A ferrule for use in forming a sling eye comprising an integral member having two communicating passageways, each of said passageways having a cross section which is substantially uniform, the cross-sectional area of one of said passageways being larger than .the crosssectional arca of the other passageway with which communicating, said ferrule being formed from a composition containing about 0.25% copper, 0.6% silicon, 1% manganese, 0.25% chromium and the remainder aluminum.

References Cited in the file of this patent UNITED STATES PATENTS 1,334,244

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