Patent Application
20140311323
The present disclosure relates generally to the technical field of synthetic ropes and, more particularly, to a rope that preferably is made from synthetic polymeric material, that has a rather high breaking strength and that also has a rather light weight compared to steel wire rope and that is capable of being used with powered blocks, traction winches, powered winches, powered drums, drum winches, powered capstans and in general any powered turning element and/or rotating element capable of applying force to a rope (hereinafter aggregately known as “powered blocks”). Such synthetic ropes include but are not limited to tow ropes, towing warps, trawl warps (also known as “trawl warps”), deep sea lowering and lifting ropes, powered block rigged mooring ropes, powered block rigged oil derrick anchoring ropes used with blocks and also with powered blocks, superwides and paravane lines used in seismic surveillance including but not limited to used with towed arrays, helicopter ropes, yachting ropes, rigging ropes for pleasure craft including but not limited to sail craft, running rigging, powered block rigged anchor ropes, drag lines, and any other type of rope and/or cable without exception (the term “rope” and the term “cable” being interchangeable for purposes of the present disclosure).
High strength synthetic ropes formed mainly of super-fibers such as Dyneema® (formed of UHMWPE), PBO Zylon and others are important to use in substitution of steel wire rope in many applications and especially applications where human safety and life are at risk from operation of steel wire ropes. Such applications include but are not limited to applications utilizing powered blocks. In such applications, the energy released from a wire rope breaking while subject to tension can be sufficient to cause a recoiling section of the wire rope to cut through steel plate and is known to sever limbs and to cause death of persons in and about the vicinity of the wire rope. In addition to crippling and fatal injuries resulting from failure of wire rope when under tension, due to its heavy weight the use of wire rope results in an unacceptable risk of back injuries to persons responsible for utilizing wire rope, including loading the wire rope onto deployment equipment including cranes or utilizing the wire rope in dynamic applications such as tug ropes and tie up lines. Oppositely, state of the art high strength synthetic ropes are light in weight and not a notable risk factor for back injuries of persons charged with deploying the synthetic ropes, and also do not store sufficient kinetic energy at breaking point to make them notably dangerous should they break while subject to tension. Thus, it readily can be appreciated that it is important to substitute wire ropes by high strength synthetic ropes for at least applications and uses involving powered blocks, especially cranes and other applications using drum winches as well as using capstans, as well as any other applications and uses where the rope and/or cable is used where persons are in the vicinity of any portion of the rope and/or cable—or where persons are able to be struck by portions of the rope or related equipment in the event of a failure and recoil of the rope and/or cable.
However, due to problems associated with the deployment of high strength synthetic ropes with powered blocks, wire ropes continue to be used in applications where their heavy weight in comparison to synthetic ropes causes back injuries of persons deploying the wire ropes and also where their failure when subject to load causes maiming and death of persons in the vicinity of the wire rope.
A main problem impeding the adoption of high strength synthetic ropes in substitution of wire ropes for use in conjunction with powered blocks and other applications is that high strength synthetic ropes exhibit rather low surface friction and thus rather low traction in comparison to the surface friction and traction exhibited by wire ropes, especially when deployed with powered blocks, or in applications requiring various portions of the rope to grab itself, such as in logging operations. The low surface friction, especially with wet or greasy surfaces, allows the high strength synthetic ropes to slide upon the gripping surface of powered blocks, and also to slide upon corresponding surfaces of subsequent layers of the synthetic rope. When the high strength synthetic rope is loaded and stored upon a high tension drum winch, the low surface friction allows slippage of layers of the rope loaded upon the drum winch with the result that subsequently formed wrappings of the high strength synthetic rope stored upon the drum winch under tension are often forced in between prior formed wrappings of the rope, causing tangles and back lashes. The tangles and backlashes cause economic losses from downtime caused by a need to untangle the tangles and backlashes and to repair equipment failures caused by such tangles and backlashes. However, and much more seriously, the tangles and backlashes are a great danger to the safety, life and limb of crewmen and equipment operators working in the vicinity of the high strength synthetic ropes, as the tangles and backlashes can cause moments of tremendous shock when the tangles and backlashes release and thereby cause a sudden cessation of tension followed by a sudden shock load of tension that, even when the high strength synthetic rope itself does not fail, has been known to cause failure of equipment with which is deployed the high strength synthetic rope, such as blocks and sheaves, resulting in a sudden redirection of the position of both such associated equipment as well as the high strength synthetic rope under high velocities and high tensions, with fatalities known to occur.
In addition to the very serious issues of safety and welfare of life and limb of persons in and about a steel wire rope under tension in, very real and serious economic consequences caused by the relatively low traction of synthetic super-fiber ropes in comparison to steel wire cables continue to plaque and increasingly cause serious economic harm to certain industries. One of these industries is oil exploration and development. In this field, an increasing need for research and equipment installation is occurring in deeper and deeper maritime waters, known as the deep sea. This increasing need for research and equipment installation in the deep sea is requiring longer and longer lengths of cable to be used. Due to the relatively high density of steel wire cable in air and water including salt water the progressively and increasingly long lengths of cable are hampering research and development efforts due to the fact that the weight of the metal cables consumes so much payload by its own weight that often insufficient payload capacity remains for other equipment. In extreme cases, the steel wire used in deep sea applications and when long lengths are employed breaks under its own weight. Furthermore, existing cranes, lifting gear and winches on vessels are not capable of bearing the weight required to deploy the needed lengths of wire for more and more deep sea applications. Thus, in addition to the long felt and pressing safety needs for a low energy retaining synthetic rope having sufficient traction so as to permit it to replace steel wire rope, it can readily be appreciated that a long felt and pressing economic need exists in the industry for a light weight, high strength synthetic rope exhibiting sufficient traction so as to permit it to substitute steel wire rope for applications presently experience serious economic hampering due to the use of steel wire ropes and/or cables, such as in deep sea applications.
Attempts to solve this problem include:
a) forming jackets of steel wire around strength members formed of high strength synthetic fibers (the term “fiber” may be used interchangeably herein with the term “filament”);
b) mixing relatively low strength synthetic fibers exhibiting relatively high friction with super-fibers exhibit relatively low friction, forming strands of such combinations of fibers and subsequently forming an external cover around a high strength synthetic strength member with such strands;
c) wrapping strands formed of high strength super-fibers with a thin layer of strands formed of relatively high friction and relatively low strength fibers, and forming a rope from such wrapped strands (such as taught in U.S. Pat. No. 7,735,308 and U.S. Pat. No. 7,908,955); and
d) forming synthetic coatings around strength members where either the entire strength member is sealed off from the outside environment by the synthetic coating, or where the synthetic coating lies in between adjacent strands forming the outside layer of strands forming the rope and/or cable, so that the outside surface of the rope and/or cable includes both the synthetic coating as well as strands of the cable protruding from the synthetic coating.
Known constructions of synthetic and steel rope intended for use where high traction is desired either:
a) include no cover around the strength member, where the strength member is mixed with strands including relatively low strength and high friction strands;
b) include a cover around the strength member where portions of the strength member protrude from the cover so that such portions of the strength member can contact working surfaces and provide traction;
c) include a final layer of strands that form a cover around the strength member where such final layer of strands have either the same or similar pitch as a majority of strands forming the remainder of the strength member, or a greater pitch as the majority of strands forming the strength member, and are designed and configured to share load bearing capability in proportion with all of or with the majority of strands forming the strength member.
Other art teaches adhering a relatively high friction coating directly to a strength member, or adhering a low friction coating directly to a strength member, or otherwise forming a strength member with super-fibers having relatively low friction but attaching to the outside of the strength member a substance having a higher friction than the super-fibers forming the strength member. For example, a relatively high friction substance may be attached directly to the strength member by coating the strength member with a relatively high friction substance, or by wrapping the strength member with fibers and/or strands (including yarns) formed of a relatively high friction substance, or by coating and/or wrapping strands that form the strength member with a relatively high friction substance and then forming the strength member with such strands so that the outside surface of such strength member is entirely or mainly covered by such relatively high friction substance (such as for example taught in U.S. Pat. No. 7,735,308 and U.S. Pat. No. 7,908,955).
The known art for forming a high friction strength member rope and/or cable includes a construction for such rope and/or cable where the rope and/or cable exhibits a lateral deformation when subject to a certain tension and when deployed against a hard working surface of a traction winch and/or drum winch that is a lateral deformation of the cross sectional form of the rope and/or cable exhibited in such circumstances by known steel wire rope, it being the trend in the industry and the state of the art to preserve the ability of a high traction rope to exhibit such lateral deformation, it being the predominant belief held in the industry that such lateral deformation is important to maintaining and/or maximizing the ability of the rope and/or cable to exhibit a desired and needed traction.
However, none of the known art has presented a suitable solution to the problem of backlashes and tangles resultant of the use of high strength synthetic ropes with powered blocks.
Thus, due to the economic consequences of the low surface friction exhibited by high strength synthetic ropes, especially in wet and/or greasy environments, wire ropes continue to be deployed at a high rate even where loss to human life and limb are likely to occur, and do in fact occur in the event of failure of the loaded and/or tensed wire rope.
Thus, it readily can be appreciated that a long felt and pressing need exists in the industry for a construction for a high strength synthetic rope that is readily able to be used in conjunction with powered blocks without incurring the risk of back lashes and tangles, and without notably increasing the failure rate of drum winch side walls.
Thus also, it readily can be appreciated that a long felt and pressing need exists in the industry for a high strength synthetic rope that is readily able to be used in conjunction with powered blocks where such high strength synthetic rope exhibits a surface friction against a steel and/or iron surface when exposed to wet and/or greasy conditions where such surface friction is at least greater than the surface friction presently exhibited by known high strength synthetic ropes in such conditions, and preferably where such surface friction is similar to or greater than the surface friction of steel and/or iron in such wet and/or greasy conditions.
Published Patent Cooperation Treaty (PCT) International Publication Number WO 2004/020732 A2, International Application Number PCT/IS2003/000025 discloses a cable having a thermoplastic core within a braided synthetic strength member. The cable is a heat stretched cable exhibiting ultra compactness and is useful for high tension powered block applications. In one embodiment, disclosed is a cable wherein the material of the thermoplastic core contacts both the synthetic strength member and a braided synthetic sheath formed about the outside of the strength member. However, this embodiment has failed to be commercially accepted for the reasons taught above, i.e. due to the fact that the strength of the cable is reduced by such construction.
In all embodiments, it is taught that the heat stretching and compacting of the cable is accomplished either by simultaneously heating and stretching with tension the combination of the strength member, the thermoplastic core and a second sheath formed about the thermoplastic core and also contained within the strength member, the purpose of such second sheath being to prevent uncontrolled flow of molten phase of the thermoplastic core during processing of the rope, or by first applying the heat and subsequently applying the tension. This cable has found more commercial acceptance than any other synthetic rope for use with high tension powered blocks, and is the only viable synthetic rope in the known art for use with high tension powered blocks such as trawler winches for purposes such as trawl warps, and this cable and its taught manufacturing processes represent both the state of the art as well as the trend in the industry.
PCT/IS2010/000012 (publication WO 2011/027367) teaches a method and construction forming a high strength synthetic rope for powered blocks where such method and construction includes adhering an external braided sheath to a strength member by means of a highly elastic substance such as a bi-component polyurethane blend, and includes forming a layer of such substance about the external surface of the braided sheath. This teaching provides for a very low surface friction in wet and/or greasy conditions, especially marine conditions.
None of the known art teaches a method or construction for a high traction synthetic strength member containing rope as taught in the present disclosure.
It is an object of the present disclosure to provide for a high strength synthetic strength member containing rope for use with powered blocks that addresses the above stated long felt needs in the industry.
It is an object of the present disclosure to provide for a high strength synthetic rope that is readily able to be used in conjunction with powered blocks while presenting a reduced risk of back lashes and tangles in comparison to known synthetic ropes, and while notably decreasing the failure rate of drum winch side walls in comparison to the failure rate exhibited by such drum winch side walls when such drum winches are used with known synthetic ropes.
It is another object of the present disclosure to provide for a high strength synthetic rope that is readily able to be used in conjunction with powered blocks where such high strength synthetic rope exhibits a surface friction against a steel and/or iron surface when exposed to wet and/or greasy conditions where such surface friction is at least greater than the surface friction presently exhibited by known high strength synthetic ropes in such conditions, and preferably where such surface friction is similar to or greater than the surface friction of steel and/or iron in such wet and/or greasy conditions.
Disclosed is a method for producing a high strength synthetic strength member containing rope capable of being used with powered blocks where such rope has lighter weight and similar or greater strength than steel wire strength member containing ropes used with powered blocks, while concurrently exhibiting similar or greater friction against a steel and/or iron surface in wet and/or greasy conditions in comparison to a surface friction in such conditions exhibited by steel wire. Disclosed also is the product resulting from such method.
Most broadly, the product includes a synthetic strength member, a first synthetic portion situated between a braided sheath and the strength member and adhering the braided sheath to outside surface of the strength member, a second synthetic portion situated external the braided sheath and adhered to the outside surface of the braided sheath, portions of material adhered to the second synthetic portion and protruding from the outside surface of the second synthetic portion and from the outside surface of the rope, the portions of material adhered to the second synthetic portion being formed of a material that:
a) differs from a substance mainly forming the second synthetic portion situated external the braided sheath (i.e. the second synthetic portion);
b) has a different hardness than the substance mainly forming the synthetic portion situated external the braided sheath (i.e. the second synthetic portion);
c) has a higher friction when wet and/or in a greasy environment than does the substance mainly forming the synthetic portion situated external the braided sheath (i.e. the second synthetic portion); and
d) may have a different affinity to water, and may have a greater affinity to water and in some cases a lesser affinity to water than is the substance mainly forming the synthetic portion situated external the braided sheath (i.e. the second synthetic portion).
Portions of leather, such as portions of raw hide leather obtained by grinding dry raw hide, are presently preferred for use as the portions of material adhered to and protruding from the outside surface of the second synthetic portion, as are portions of rubber such as portions of rubber obtained by grinding tires.
Preferably, the elasticity of the first and second synthetic portions is in a range of elasticity of from twenty percent (20%) to five hundred fifty percent (550%) measured at any temperature within two (2) degrees C. of zero (0) degrees C. being preferred.
In a most preferred embodiment, an additional synthetic substance is situated within the interior of the strength member and the strength member is a hollow braided strength member that has been formed about this additional synthetic substance when such additional synthetic substance was a solid core of thermoplastic material, and subsequent to forming the strength member about such solid core of thermoplastic material, the combination of the thermoplastic core and the strength member were subjected to sufficient heat to permit flowing the thermoplastic core and were also subjected to sufficient tension to permanent permanently elongating the strength member as well as fibers forming the strength member, followed by cooling the combination of the strength member and thermoplastic core while they are under tension until the cooling is completed, followed by adhering the braided sheath to the strength member with the first synthetic portion, followed by applying the second synthetic portion to the outside surface of the braided sheath where either or both:
a) The portions of material formed of a substance that differs from the substance forming the second synthetic portion are included within the second synthetic portion prior to applying it to the outside surface of the braided sheath; and/or
b) The portions of material formed of a substance that differs from the substance forming the second synthetic portion are contacted to the second synthetic portion after situating the second synthetic portion about the outside surface of the braided sheath, such as may be accomplished by for example blowing, dropping or pressing onto the surface of the second synthetic portion such portions of material formed of a substance that differs from the substance forming the second synthetic portion.
The preferred dimensions of the portions of material formed of a substance that differs from the substance forming the second synthetic portion is approximately one half (0.5) millimeters in a granular shape, and also one half (0.5) millimeters if a fiber or filamentous shape is used.
In order to affix the portions of material formed of a substance that differs from the substance forming the second synthetic portion to the second synthetic portion and thus to the outside surface of the rope:
A die or a roller die preferably is used to smooth the second synthetic portion including the portions of material formed of a substance that differs from the substance forming the second synthetic portion into a uniform shape about the outside surface of the braided sheath after either:
a) contacting to the second synthetic portion the portions of material formed of a substance that differs from the substance forming the second synthetic portion; or
b) applying to the outside surface of the braided sheath while it is in a liquid or semi-liquid state a blend formed of a combination of the substance forming the second synthetic portion with the portions of material formed of a substance that differs from the substance forming the second synthetic portion.
Alternatively, the second synthetic portion may first be contacted to the external surface of the braid sheath, subsequently smoothed into a desired or uniform shape by use of a die, and the portions of material formed of a substance that differs from the substance forming the second synthetic portion subsequently may be contacted to the second synthetic portion, to which they permanently adhere upon setting (including “drying”) of the substance forming the second synthetic portion.
In the most preferred embodiment of the present disclosure, the braided sheath is formed with a construction and configuration that prohibits strands forming the braided sheath to bear a proportional amount of load (including tension) in comparison to the majority of strands forming the strength member, such that strands forming the braided sheath bear a lesser amount of load in proportion to their breaking strength in comparison with most of the strands forming the strength member, and preferably in comparison with all of the strands forming the strength member, when the rope is loaded to at least ten percent (10%) of its maximal load bearing capability (i.e. its “breaking load”). One construction for a sheath for the rope of the present disclosure that provides for this important requirement is a braided cover formed of strands of synthetic material where the strands forming the braided cover have a lesser pitch than do a majority of strands forming the strength member, and preferably have a lesser pitch than do all strands forming the strength member. This construction and configuration for a high traction synthetic rope provides for optimal friction and traction when used as the braided sheath for the rope of the present disclosure and is contrary to the state of the art and against the trend in the industry for a construction and configuration of the external strand layer of a high traction rope.
An advantage of the disclosed high traction synthetic rope for powered blocks is that it permits reduced side wall dimensions for drum winches, thus permitting reduced costs associated with machinery and superstructures and associated costs for floating mooring and/or anchor lines needed to anchor oil derricks, especially deep water oil derricks and other floating structures, and trawling vessels.
Another advantage of the disclosed high traction synthetic rope for powered blocks is that it permits for much increased safety of persons in and about the vicinity of the rope during operation and use of the rope.
Yet another advantage of the disclosed high traction synthetic rope for powered blocks is that it reduces downtime, and reduces operational costs, and reduces initial equipment acquisition costs as it does not require as strong side walls on drum winces, for example.
Yet another advantage of the disclosed high traction synthetic rope for powered blocks is that due to its increased traction it requires less handling time to accomplish many tasks.
Yet another advantage of the disclosed synthetic rope for powered blocks is that due to its increased traction it improves predictability of operational events and reduces operational risks.
Possessing the preceding advantages, the disclosed high traction synthetic rope for powered blocks answers needs long felt in the industry.
It can readily be appreciated that these and other features, objects and advantages are able to be understood or apparent to those of ordinary skill in the art from the following detailed description of the preferred embodiment as illustrated in the various drawing figures.
Lead core 2 is optional, and is preferred for trawl warp applications and in the case of certain other applications, but not necessarily in the case of anchor lines and deep water oil derrick mooring and/or anchoring lines or yachting lines, although in some cases it may be used in such applications. In substitution of lead core 2 a core of conductors capable of transmitting electrical and/or light energy, data and power, is useful. In such embodiments, the conductors are initially slack when the strength member is formed around the thermoplastic core and subsequently become elongated during permanent elongation of the strength member, but not elongated an amount and/or distance sufficient to cause failure or breakage of the conductors.
Thus, the present disclosure teaches: A synthetic rope exhibiting improved traction comprising a strength member formed mainly of fibers, a braided sheath formed mainly of fibers, a first synthetic portion adhering the braided sheath to the outside surface of the strength member, a second synthetic portion situated upon the outside surface of the braided sheath and adhering portions of material formed of a substance that differs from a substance mainly forming the second synthetic portion, where the portions of the material formed of a substance that differs from the substance mainly forming the second synthetic portion exhibit differing characteristics in comparison with a substance mainly forming the second synthetic portion, the differing characteristics being selected from a group consisting of:
a) a different hardness;
b) the portions of material exhibiting a greater affinity for water than is exhibited by the substance forming and/or mainly forming the second synthetic portion;
c) the portions of material exhibiting a different elasticity than is exhibited by the substance forming and/or mainly forming the second synthetic portion;
d) the portions of material exhibiting a different elasticity, and preferably a lesser elasticity at a temperature that is about zero degrees Celsius than is exhibited by the substance forming and/or mainly forming the second synthetic portion; and
e) the portions of material exhibiting a greater friction when wet and measured on an iron surface than is exhibited by the substance forming and/or mainly forming the second synthetic portion.
By far the most important of the differing characteristics being that the portions of material exhibit a greater friction when wet and measured on an iron surface in comparison with a friction exhibited by the second synthetic portion when wet and measured on an iron surface.
The present disclosure provides several examples of methods of the present disclosure for forming a high traction synthetic rope of the present disclosure:
The present disclosure teaches: A method for forming a synthetic rope (1) exhibiting improved traction, the method comprising steps of:
firstly, forming a strength member (7);
secondly, situating an adhesive substance forming a first synthetic portion (9) about the outside surface of the strength member;
thirdly, forming a braided sheath (8) about the combination of the strength member and the adhesive substance forming the first synthetic portion;
fourthly, adhering to the outside surface of the braided sheath by means of a second adhesive substance forming a second synthetic portion (21) portions of material formed of a substance that differs from a substance mainly forming the second synthetic portion, the method including steps of selecting for the portions of the material formed of a substance that differs from the substance mainly forming the second synthetic portion a substance exhibiting differing characteristics in comparison with a substance mainly forming the second synthetic portion, and selecting the differing characteristics from a group consisting of:
a) a different hardness;
b) a greater affinity for water being exhibited by the portions of material than is exhibited by the substance mainly forming the second synthetic portion; and
c) a greater friction when wet and measured on an iron surface being exhibited by the portions of material than is exhibited by the substance mainly forming the second synthetic portion.
The present disclosure also teaches modifying the above method by any or all of the following teachings:
a) selecting a blending machine to blend together two or more substances that when set form a polyurethane and situating such blend of substances upon the outside surface of the strength member (7) to serve as the first synthetic portion (9);
b) selecting a set time for the blend of substances that is less than ninety minutes;
c) selecting a temperature that is lesser than ninety degrees Celsius for a temperature of the blend of substances at the moment the blend of substances is situated upon the outside surface of the strength member (7);
d) selecting a blending machine to blend together two or more substances that when set form a polyurethane and situating such blend of substances upon the outside surface of the braided sheath (8) to serve as the second synthetic portion (21);
e) selecting a set time for the blend of substances that is less than ninety minutes; and
f) selecting a temperature that is lesser than ninety degrees Celsius for a temperature of the blend of substances at the moment the blend of substances is situated upon the outside surface of the braided sheath (8).
The present disclosure also teaches a method for forming a synthetic rope (1) exhibiting improved traction, the method comprising steps of:
firstly, forming a strength member (7) mainly of synthetic fibers;
secondly, forming a substance forming a first synthetic portion (9) about the outside surface of the strength member, where the substance forming the first synthetic portion is capable of exhibiting during its set phase a first elastic substance capable of affixing the strength member to a braided sheath formed about the outside of the strength member;
thirdly, forming a braided sheath (8) mainly of synthetic fibers and about the combination of the strength member and the substance forming the first synthetic portion;
fourthly, causing to be formed upon the outside surface of the braided sheath a combination of a substance forming a second synthetic portion and a third substance, the method further including steps: of selecting for the substance forming the second synthetic portion a substance that when in its set phase forms an elastic substance thereby forming a second elastic substance; selecting for the third substance a substance that differs from the substance mainly forming the second synthetic portion and that is capable of exhibiting during a set phase of the third substance a substance exhibiting a greater friction when wet and measured on an iron surface in comparison with a friction exhibited by a set phase of the substance mainly forming the second synthetic portion when wet and measured on the iron surface; further selecting for the substance forming the second synthetic portion a substance that upon setting of a non-solid phase of the substance forming the second synthetic portion forms an elastic substance capable of serving as a connector that holds the portions of material (23) both to the substance forming the second synthetic portion as well as to the outside surface of the braided sheath; the method further including steps of setting at least the substance forming the first synthetic portion and the substance forming the second synthetic portion; the method further including steps of selecting the set phase of the third substance as final phase of the third substance in the finished rope produced by the method, the third substance thereby forming the portions of material (23) formed of a substance that exhibits a greater friction when wet and measured on an iron surface in comparison with friction exhibited by the substance mainly forming the second synthetic portion when wet and measured on the iron surface, thereby providing for a synthetic strength member containing rope having light weight in comparison to steel wire rope and less ability to store kinetic energy in comparison to steel wire rope while also thereby increasing traction of the synthetic strength member containing rope and improving its safety of operation and its economy of operation.
The method of claim 9 where the method includes further steps of introducing non-solid portions of material forming the third substance to the second synthetic portion during either non-solid or set phases of the second synthetic portion, followed by setting at least the non solid portions of material that were contacted to the surface of the second synthetic portion into the portions of material (23), thereby permitting the final high traction synthetic rope of the present disclosure to exhibit an outside surface including both the set phase of the second synthetic portion as well as the set phase of the portions of material (23).
The method of claim 9 where the method includes further steps of introducing non-solid portions of material that are capable of setting into the portions of material (23) into a non-set phase of the substance that sets to form the set phase of the second synthetic portion, where the non-solid phase of the portions of material that set to form the portions of material (23) are not solved into the non-set phase of the second synthetic portion, followed by steps of setting both the third substance and the substance forming the second synthetic substance thereby permitting the final high traction synthetic rope of the present disclosure to exhibit an outside surface including both the set phase of the second synthetic portion as well as portions of material that are distinct from the set phase of the second synthetic portion and are the set phase of the portions of material (23), thereby permitting the final high traction synthetic rope of the present disclosure to exhibit an outside surface including both the set phase of the second synthetic portion as well as the set phase of the portions of material (23).
The method of claim 9 where the method includes further steps of selecting to introduce a set phase of the portions of material (23) into a non set phase of the second synthetic portion after forming the second synthetic portion about the outside surface of the braided sheath, thereby permitting the final high traction synthetic rope of the present disclosure to exhibit an outside surface including both the set phase of the second synthetic portion as well as the set phase of the portions of material (23).
The method of claim 9 where the method includes further steps of selecting to introduce a set phase of the portions of material (23) into a non set phase of the second synthetic portion so as to form a mixture including the set phase of the portions of material (23) and the non-set phase of the second synthetic portion prior to forming the second synthetic portion about the outside surface of the braided sheath, followed by selecting to form about the outside surface of the braided sheath the mixture of the set phase of the portions of material (23) and the non-set phase of the second synthetic portion, thereby permitting the final high traction synthetic rope of the present disclosure to exhibit an outside surface including both the set phase of the second synthetic portion as well as the set phase of the portions of material (23).
The method of claim 9 where the method includes further steps of selecting to introduce a set phase of the portions of material (23) into a set phase of the second synthetic portion after forming the second synthetic portion about the outside surface of the braided sheath and affixing the portions of material (23) to the second synthetic portion, thereby permitting the final high traction synthetic rope of the present disclosure to exhibit an outside surface including both the set phase of the second synthetic portion as well as the set phase of the portions of material (23).
The present disclosure also teaches a method for forming a synthetic rope (1) exhibiting improved traction, the method comprising steps of:
firstly, forming a strength member (7) mainly of synthetic fibers;
secondly, situating an adhesive substance forming a first synthetic portion (9) about the outside surface of the strength member, where the adhesive substance forming the first synthetic portion is capable of setting to form an elastic substance;
thirdly, forming a braided sheath (8) mainly of synthetic fibers and about the combination of the strength member and the adhesive substance forming the first synthetic portion;
fourthly, situating upon the outside surface of the braided sheath surrounding the strength member a combination of a non-solid substance forming a second synthetic portion and non-liquid substance, the method further including steps: of selecting for the non-solid substance a substance that when set forms an elastic substance; selecting for the non-liquid substance portions of material (23) formed of a substance that differs from a substance mainly forming the non-solid substance; further selecting for the non-solid substance an adhesive substance that upon setting of the non-solid substance forms the elastic substance forming the second synthetic portion while also affixing the portions of material (23) both to the elastic substance forming the second synthetic portion as well as to the outside surface of the braided sheath; the method further including steps of selecting for the portions of material (23) a material formed of a substance that exhibits a greater friction when wet and measured on an iron surface in comparison with friction exhibited by the substance mainly forming the second synthetic portion when wet and measured on the iron surface, thereby providing for a synthetic strength member containing rope having light weight in comparison to steel wire rope and less ability to store kinetic energy in comparison to steel wire rope while also thereby increasing traction of the rope and improving its safety of operation and its economy of operation.
The present disclosure also teaches a method for forming a synthetic rope (1) exhibiting improved traction, the method comprising steps of:
firstly, forming a strength member (7) mainly of synthetic fibers;
secondly, situating a substance forming a first synthetic portion (9) about the outside surface of the strength member, where the substance forming the first synthetic portion is capable of setting to form an elastic substance capable of adhering the strength member to a braided sheath formed about the outside of the strength member;
thirdly, forming a braided sheath (8) mainly of synthetic fibers and about the combination of the strength member and the adhesive substance forming the first synthetic portion;
fourthly, forming upon the outside surface of the braided sheath surrounding the strength member a combination of a non-solid substance forming a second synthetic portion and a third substance, the method further including steps: of selecting for the non-solid substance a substance that when set forms a second elastic substance; selecting for the third substance a substance that differs from the substance mainly forming the second synthetic portion and that is capable of exhibiting during a set phase of the third substance a substance exhibiting a greater friction when wet and measured on an iron surface in comparison with friction exhibited by a set phase of the substance mainly forming the second synthetic portion when wet and measured on the iron surface; further selecting for the non-solid substance a substance that upon setting of the non-solid substance forms the elastic substance forming the second synthetic portion while also affixing the portions of material (23) both to the substance forming the second synthetic portion as well as to the outside surface of the braided sheath; the method further including steps of setting at least the substance forming the first synthetic portion the substance forming the second synthetic portion and selecting the set phase of the third substance for the final phase of the third substance, the third substance thereby forming the portions of material (23) formed of a substance that exhibits a greater friction when wet and measured on an iron surface in comparison with friction exhibited by the substance mainly forming the second synthetic portion when wet and measured on the iron surface, thereby providing for a synthetic strength member containing rope having light weight in comparison to steel wire rope and less ability to store kinetic energy in comparison to steel wire rope while also thereby increasing traction of the synthetic strength member containing rope and improving its safety of operation and its economy of operation.
The above methods for forming the high traction synthetic rope of the present disclosure may includes steps of spraying or dropping or injecting or extruding non-solid portions of material onto the surface of the second synthetic portion during either the non-solid or the set phase of the second synthetic portion, where the non solid portions of material that were contacted to the surface of the second synthetic portion set into the portions of material (23); or
introducing the non-solid portions of material that set into the portions of material (23) into a non-set phase of a substance that sets to form the set phase of the second synthetic portion, such as may be a liquid and/or semi-liquid blend of two or more substances capable of setting to form the set phase of the second synthetic portion, where the non-solid phase of the portions of material that set to form the portions of material (23) are do not homogenize into and with the non-set phase of the second synthetic portion, thereby permitting the final high traction synthetic rope of the present disclosure to exhibit and outside surface including both the set phase of the second synthetic portion as well as the set phase of the portions of material (23).
In all examples provided above of methods for forming a rope of the present disclosure, it is highly preferable that:
A) the substance forming the first synthetic portion exhibits during its set phase:
i) an elasticity of at least eighty-two percent at a temperature that is within five degrees Celsius of negative five degrees Celsius; and
ii) a tear strength that exceeds a tear strength of silicone; and
B) the second synthetic portion also exhibits during its set phase the same characteristics mentioned supra as preferable for the set phase of the first synthetic portion.
However, it is preferably that the elasticity of the set phase of both the first and second synthetic portions be in a range of elasticity of from twenty-nine percent (29%) to five hundred fifty percent (550%) measured at any temperature within five degrees C. of negative five degrees C., while the tear strength of both the first and second synthetic portions exceeds the tear strength of silicon. Furthermore, it is preferable that a tear strength of the set phase of the portions of material (23) also exceeds the tear strength of silicone.
The methods of the present disclosure may further include steps of selecting a treatment being selected from group consisting of: plasma treatment; electrical arching; sputtering; and corona treatment, to facilitate affixing to one another a set phase of any of the synthetic substances included in the rope or for affixing any of the items included in the rope to any other item forming the rope, such as for affixing the portions of material (23) to the second synthetic portion and most preferably to a set phase of the second synthetic portion.
There are two preferred embodiments of the present disclosure: one is a rope of the present disclosure for use in applications where the rope of the present disclosure is subject to storage under high compressive pressure, such as when used with high tension winches and drums, such as when used as a trawler's warp; another is where the rope of the present disclosure is not subject to storage under high compressive pressure, such as is common in many yachting applications, the main difference between the two preferred embodiments being the selected construction and characteristics of the strength member and what it contains within itself:
In forming a preferred embodiment of the present disclosure for use in applications where the rope of the present disclosure is subject to storage under high compressive pressure:
First is provided a strength member formed of synthetic fibres including polyethylene, especially HMWPE, UHMWPE and Liquid Crystal Polymer (LCP). The strength member may be parallel laid, laid (including twisted) or braided. A braided strength member having several strands formed of twisted (laid) fibers is the preferred embodiment. For example a braided strength member having a minimum of eight plates, preferably ten strands, more preferably twelve strands, yet more preferably 14 strand and yet more preferably from 16 strands to 108 strands or even more as the diameter of the rope requires, is preferred. Any conventional construction type for a braided strength member may be used. However, it is highly preferably and important for a preferred embodiment of the instant disclosure that a braided strength member is selected that has a thermoplastic core shaped so as to support the natural interior shape of the braided strength member under tension approaching breaking strength of the strength member. Preferably, for a strength member is provided a braided strength member where the fibers forming the strength member have been creeped after the fibers have been braided into the strength member, rather than prior to braiding the fibers into the strength member, and where the resultant strength member is unable to elongate greater than 5% before reaching break point when measured at a original tension of 1000 kg, and preferably so that the resultant strength member is unable to elongate greater than 4% before reaching break point when measured at a original tension of 1000 kg, and yet more preferably is unable to elongate more than 3.6% before reaching break point when measured at a original tension of 1000 kg.
In forming a strength member for the preferred form of the instant disclosure the following step are employed:
First; fibers are selected that are able to be creeped as taught above and herein.
Second; a thermoplastic linear element is provided that mainly is formed with a thermoplastic that shall be capable of exhibiting a flowable state (i.e. that shall be in a liquid state but more preferably that shall be semi-liquid, i.e. in a molten phase) when such thermoplastic is at a temperature that is a temperature that is more than eight degrees C. lesser than a temperature at which the selected fibers experience a phase change, and more preferably at least ten degrees lesser, yet more preferably at least fifteen degrees lesser than and yet even more preferably at least nineteen degrees lesser than such temperature at which the selected fibers experience a phase change, which is contrary to the state of the art and against the trend in the industry, surprisingly resulting in an unexpected increase in strength of the final formed rope.
The thermoplastic linear element is preferably a rod formed of thermoplastic (the term “formed of thermoplastic” is understood to include being formed of a sufficient quotient of thermoplastic so as to permit the linear element to experience the semi-liquid, i.e. molten phase during the circumstances taught supra and herein, even though other substances might be included with the thermoplastic, or even lead or other metal or heavy plastic might be included in linear arrangement within the center of the thermoplastic linear element that preferably is a rod, so as to increase weight in water of the final product rope of the present disclosure).
Third; a flow-shield sheath is formed around the thermoplastic rod. Any construction for a sheath that mainly stops liquid and semi-liquid phases of the thermoplastic core from existing the walls of the flow sheath also are useful in forming the flow-shield sheath. In a presently preferred embodiment, a tightly woven braided flow-shield sheath is braided around the thermoplastic rod. Fibers are selected to form the flow-shield sheath that are not made either liquid or semi-liquid at a temperature selected to either or both creep the fibers or change the phase of either the fibers or the thermoplastic rod, but rather that have a much higher softening point. Polyester is suitable.
Fourth; when it is selected to form the flow-shield sheath from a braided structure, the selected fibers are braided around the linear element formed of a thermoplastic and its flow-shield sheath, such as a thermoplastic rod surrounded by a flow-shield sheath, so as to form a braided strength member including a thermoplastic core surrounded by a flow-shield sheath.
Fifth; the braided strength member having the thermoplastic rod surrounded by the flow-shield sheath as its core is then subject first to tension and secondly to heat, while maintaining the tension, in such a fashion and under such conditions so as to permit permanently elongating both the fibers forming the strength member, as well so as to permit permanently elongating the strength member itself. A thermoplastic is selected to form the thermoplastic core that shall preferably become semi-liquid, i.e. molten, at the temperature used to permanently elongate the fibers and braided strength member formed of the fibers. The flow shield-sheath mainly or entirely stops the phase changed thermoplastic core from exiting the flow-shield sheath. That is, the majority of the thermoplastic core is unable to exit the flow-shield sheath even when the thermoplastic core is either liquid or semi-liquid, i.e. molten, despite enormous constrictive and compressive forces applied to the phase changed thermoplastic core as a result of the high tensions applied to the strength member, such high tensions able to permanently elongate the strength member under the conditions taught supra and herein.
Applying tension before applying the heat at a temperature that is not within 8 degrees C. of a temperature at which fibers mainly forming the synthetic strength member undergo a phase change and that also is a temperature that when stretching the rope is a temperature that is sufficient to cause permanent elongation of both the strength member as well as the fibers mainly forming the strength member, while then maintaining the tension while the heat is being applied is important, and is contrary to the state of the art and against the trend in the industry.
A preferred tension to be used in the disclosed processes for forming the disclosed rope is about eight percent (8%) to about seventy percent (70%) of the break strength of the strength member when such break strength is measured at room temperature, with about three percent (3%) to about thirty-seven percent (37%) being preferred, and with less than fifty-five percent (55%) being most preferred. However, when forming the rope of the present disclosure without the shaped supportive core that is formed by use of and inclusion of the thermoplastic linear element in the production of the rope of the present disclosure, temperatures that are about room temperature are selected and the preferred tension to be used in the disclosed processes for forming the disclosed rope is about sixty to seventy percent (60% to 70%) of the break strength of the strength member when such break strength is measured at room temperature.
Importantly, the tension applied to the strength member, and thus necessarily also applied to the fibers forming the strength member, preferably is a static tension and/or a generally static tension and/or a very slowly fluctuating tension. After applying a predetermined tension (including approximately a predetermined tension), and while under such predetermined tension simultaneously the strength member, its fibers, and its thermoplastic core are heated to a predetermined temperature and/or to approximately a predetermined temperature as taught above and herein, and, contrary to the state of the art and against the trend in the industry, a temperature that does not approach the phase change temperature of fibers and/or fiber type mainly forming the strength member, i.e. are not within eight degrees C. of such phase change temperature, and more preferably at least ten degrees lesser, yet more preferably at least fifteen degrees lesser than and yet even more preferably at least nineteen degrees lesser than such temperature at which the selected fibers experience a phase change, which is contrary to the state of the art and against the trend in the industry, surprisingly resulting in an unexpected increase in strength of the final formed rope. The use of a long oven having many capstans able to accommodate a very long length of the strength member and turning at varying speeds and/or rates of rotation so as to maintain the tension on differing portions of the strength member located between different capstans, and thus by extension on the fibers forming the strength member as well as on the thermoplastic core also forming the strength member is highly useful, especially for permitting an endless flow production process.
Sixth; when the fibers and thus by extension the braided strength member have been elongated to a predetermined amount so as to permit a strength member having the properties described above and herein, and especially having an elongation to break point within the range of values as taught above and herein, and also the thermoplastic core has been elongated, the elongated fibers, the now elongated strength member formed of the elongated fibers and its elongated thermoplastic core are cooled while sufficient tension is maintained and applied to the strength member and thus by extension to its fibers and to its thermoplastic core during the cooling process so that all such components are cooled to their respective solid states while under a tension that results in the cooled fibers as well as the cooled strength member having been both:
I) permanently compacted so as to cause the produced strength member of the instant disclosure to exhibit less lateral deformation when subject to a certain tension and when deployed against a hard working surface of a traction winch and/or drum winch than is exhibited in such same circumstances by a known steel wire rope, which such result and characteristic is contrary to the state of the art and against the trend of the industry and against the dominant belief held in the industry, as well as;
II) permanently elongated so as to cause the strength member:
a) to acquire a lower elongation than it had prior to its having been permanently elongated;
b) to acquire a substantially lesser diameter and a greater compactness than it had prior to its having been permanently elongated;
c) to acquire to its thermoplastic content core a permanent solid shape that supports the interior cavity of the permanently elongated strength member in such a fashion that the fibers and braid strands forming the strength member are sufficiently less able to move relative to one another in a direction perpendicular to the long dimension of the permanently elongated strength member in comparison to prior to the strength member having been permanently elongated so as to reduce fiber to fiber abrasive wear, and also so as to preclude crushing of the rope, especially under high compressive forces such as occurs during winding and storage on a high tension drum, as mentioned supra, the necessary tension to achieve such result for any particular fiber type able to be experimentally determined by one of ordinary skill in the art after having read the present disclosure; and also
d) to acquire a break point that is within the range of values of elongation to break point as taught above and herein.
This cooling also is best accomplished and undertaken using capstans turning at varying speeds so as to maintain a tension on the elongated strength member and its components during the entire cooling process and period that precludes their shortening, so that the final cooled strength member has the values of elongation to break point as taught above and herein for a most preferred embodiment of the instant disclosure, and also the other properties taught as above and herein, as also is accomplishable in an endless flow production method.
In order to form a rope of the instant disclosure that is not useful for applications requiring tolerating high compressive pressures, such as applications not including a trawler's warp, and other applications not including storage of the rope of the present disclosure on high tension drums and winches, the step of forming the thermoplastic rod with its flow-shield sheath may be omitted, and the subsequent steps are carried out the same as taught above and herein except that the thermoplastic rod and its flow-shield sheath are not present nor need their properties be considered. However, when forming the rope of the present disclosure without the shaped supportive core that is formed by use of and inclusion of the thermoplastic linear element in the production of the rope of the present disclosure, temperatures that are too low to permit changing a phase of the fibers mainly forming the strength member are selected and the preferred tension to be used in the disclosed processes for forming the disclosed rope is about fifty to seventy percent (50% to 70%) of the break strength of the strength member when such break strength is measured at room temperature. The selected strength member of the rope of the present disclosure now having been formed, the remaining production steps, as already taught herein and supra, and undertaken so as to form the preferred selected high traction synthetic strength member containing rope of the present disclosure.
The present disclosure also teaches:
Selecting to form the strength member mainly of synthetic fibers that are able to be creeped and of a braided construction;
Providing a thermoplastic linear element that mainly is formed with a thermoplastic capable of exhibiting a flowable phase when such thermoplastic is at a temperature that is a temperature that is more than eight degrees C. below a temperature at which the selected fibers experience a phase change (and more preferably at least ten degrees lesser, yet more preferably at least fifteen degrees lesser than and yet even more preferably at least nineteen degrees lesser than such temperature at which the selected fibers experience a phase change, which is contrary to the state of the art and against the trend in the industry, surprisingly resulting in an unexpected increase in strength of the final formed rope);
Forming a flow-shield sheath around the thermoplastic rod;
Subjecting the braided strength member that is formed around the thermoplastic rod surrounded by the flow-shield sheath first to tension and subsequently to heat, while maintaining tension, in such a fashion and under such conditions so as to permit permanently elongating both the fibers forming the strength member and the strength member itself;
Selecting for the heat a temperature that is not within 8 degrees C. of a temperature at which fibers mainly forming the synthetic strength member undergo a phase change and that also is a temperature that when stretching the rope is a temperature that is sufficient to cause permanent elongation of both the strength member as well as the fibers mainly forming the strength member;
Cooling the strength member having been elongated to a predetermined amount as well as the thermoplastic core while maintaining sufficient tension applied to the strength member during the cooling process so that both at least the strength member and the thermoplastic core are cooled to their respective solid states while under a tension that results in the cooled fibers as well as the cooled strength member having been permanently compacted so as to cause the produced strength member of the instant disclosure to exhibit less lateral deformation when subject to a certain tension and when deployed against a hard working surface of a traction winch and/or drum winch than is exhibited in such same circumstances by a known steel wire rope.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/IS2012/050014 | 11/16/2012 | WO | 00 | 5/15/2014 |
| Number | Date | Country | |
|---|---|---|---|
| 61629303 | Nov 2011 | US |
