wire rope industries ltd free sample

YuanBo Engineering Co., Ltd., Dunamis Wire Ropes Mfg. LLP, Tokyo Rope Mfg. Co., Ltd., and Guizhou Wire Rope Incorporated Company, among others, are the top players in the bright steel wire rope market.

The global bright steel wire rope market is supported largely by the steel wire rope industry, which attained a CAGR of 3.4% in the forecast period from 2022 to 2027.

Bright steel wire ropes are general wire ropes without any coating, and free from zinc, copper, and other metallic coatings. Grease is generally used to lubricate these wires, hence preventing their deterioration. The major users of bright steel wire ropes are the oil and gas industry, shipping industry, and mining industry. Ever since the crude oil crisis, bright steel wire rope producers have seen a surge in revenue generation, especially with newer ventures for oil extraction, coal mining, and other mineral and industrial drilling.

Bright steel wire rope consumption and sales have been high in the Asia Pacific region in recent years, particularly in China, Indonesia, and India. North America and Europe are the primary areas for the global market for bright steel wire rope since they are major end-users in the oil and gas industry. During the forecasted period, the Asia Pacific countries of China, India, Indonesia, Thailand, and Malaysia are predicted to have considerable growth in the bright steel wire rope sector. Over the recent decade, China"s demand for bright steel wire rope has increased significantly, possibly because of increased steel output and infrastructure investment in lift and motion applications.

YuanBo Engineering Co., Ltd. Is the biggest bright steel wire rope manufacturer in the world. The company provides technology, solutions, and service support to meet the specific needs of customers in the pharmaceutical, chemical, fire, industrial, and other industries. As the company is located close to the northern Chinese, Tianjin port, it enjoys convenience of transport, and as a result, exports are large. It covers an area of 18000 square meters and employs more than 200 people to manufacture its goods. YuanBo exports to Europe, America, Japan, the Middle East, Africa, South Korea, and Australia.

Dunamis Wire Ropes Mfg. LLP is the largest wire rope producer in India. The various ports of Mumbai offer easy transport to other countries, hence increasing their revenue. The company provides wire ropes for a wide variety of applications such as industrial and construction work, mining, oil and gas, bridges, ski lifts, and fishing and marine.

One of the biggest wire rope manufacturers in Asia, Tokyo Rope Mfg. Co., Ltd. have built a reputation for providing the best quality in their products. The seaside ports and the immense connectivity from Japan allow for exceptional transport facilities. It is engaged in the production and sale of steel cables, steel cords, developed products, and others, the real estate leasing business, as well as logistics related business and other services.

Guizhou Wire Rope Incorporated Company is one of the largest companies specialising in steel wire rope products. The enterprise has more than 5000 employees, as they strive to achieve perfect quality control. The capacity of the company is a massive 4,00,000 metric tons a year, which they export to the United States, United Kingdom, Canada, Australia, Denmark, Netherlands, Singapore, and the Middle East.

CLEVELAND, OH – Mazzella Lifting Technologies, a Mazzella Company, is pleased to announce the acquisition of Denver Wire Rope & Supply. This acquisition will strengthen Mazzella’s footprint west of the Mississippi River and reinforce Mazzella’s commitment to be a one-stop resource for lifting and rigging services and solutions.

Denver Wire Rope & Supply has been in business since 1983 and services a variety of industries out of their location in Denver, CO. Denver Wire Rope & Supply is a leading supplier of rigging products, crane and hoist service, below-the-hook lifting devices, and certified rigging inspection and training. Effective immediately, Denver Wire Rope & Supply will operate as Mazzella / Denver Wire Rope. Terms of the transaction are not being disclosed.

“Denver Wire Rope & Supply will complement the wide range of products and services that Mazzella Companies offers. We are dedicated to being a single-source provider for rigging products, overhead cranes, rigging inspections, and rigging training. Both companies commit to a customer-first mentality, providing the highest-quality products, and leading by example when it comes to safety and sharing our expertise with customers and the market,” says Tony Mazzella, CEO of Mazzella Companies.

“Our team and family are excited to be part of the Mazzella Companies. This acquisition strengthens our place in the market and allows our team to continue to provide excellent service and products to our valued customer base and expand our offering,” says Ken Gubanich, President of Denver Wire Rope & Supply.

“Over the years, we have had numerous companies show interest in purchasing Denver Wire Rope & Supply, none seemed to be the right fit. We are looking forward to becoming a part of an aggressive, passionate, and progressive organization. As a family business for over 36 years, it is important to us that our customers/friends, suppliers, and team members continue to be treated with first-class service, products, and employment opportunities. Again, we are very enthusiastic about our future and look forward to being a quality supplier for your crane, safety training, rigging, and hoisting needs for years to come,” says Gubanich.

“We wish Ed and Carol Gubanich all the best in their retirement. We welcome Ken and the other second and third-generation Gubanich family members, as well as the entire Denver Wire Rope Team, into the Mazzella organization,” says Mazzella.

We’ve changed our name from Denver Wire Rope to Mazzella. Aside from the new name and logo, our member experience is virtually unchanged. Here are some common questions and answers related to this change.

In 2019, Denver Wire Rope & Supply was acquired by Mazzella Companies to expand lifting and rigging products and services to the western half of the United States.

In 1954, James Mazzella founded Mazzella Wire Rope & Sling Co. in Cleveland, OH. For over 65 years, the company has grown organically by nurturing historic relationships, expanding its product offerings, and entering new markets through acquisition.

Today, Mazzella Companies is one of the largest privately held companies in the lifting and rigging industries. Since our humble beginnings, we’ve grown to over 800 employees with over 30 locations across North America. Our product offerings have expanded from basic rigging products, to include:Overhead crane fabrication

D07B1/167—Ropes or cables with an enveloping sheathing or inlays of rubber or plastics characterised by a plastic or rubber inlay having a predetermined shape

D07B1/141—Ropes or cables with incorporated auxiliary elements, e.g. for marking, extending throughout the length of the rope or cable comprising liquid, pasty or powder agents, e.g. lubricants or anti-corrosive oils or greases

D07B1/144—Ropes or cables with incorporated auxiliary elements, e.g. for marking, extending throughout the length of the rope or cable comprising liquid, pasty or powder agents, e.g. lubricants or anti-corrosive oils or greases for cables or cable components built-up from metal wires

A plastic impregnated wire rope is provided with plastic bands between its core and its outer strands so as to prevent contact between the wires of the core and those of the outer strands during flexing of the rope. This produces a substantial increase in the life of the rope. The method for manufacturing such rope involves wrapping plastic bands on the core just prior to laying outer strands on the core and on top of the plastic bands. Thereafter, the so formed rope is impregnated with molten plastic, which is then allowed to solidify.

This invention generally relates to a plastic impregnated wire rope. More specifically, it relates to a wire rope that, in addition to plastic impregnation, has internal separating bands positioned between the outer strands of the rope and the core strands to prevent direct contact between these strands during flexing of the rope and thereby extend the life of the rope. The invention also relates to the method of manufacturing such wire rope. [0001] BACKGROUND OF THE INVENTION

Plastic impregnated wire ropes are well known in the art. An example of such wire rope is disclosed in U.S. Pat. No. 4,120,145 by Chiappetta et al. where a wire rope is impregnated with a plastic material between a lubricated core and lubricated outer strands of the rope. However, direct contact between the wires of the outer strands of the core and those of the outer strands of the rope will still occur during flexing of the rope under working conditions and this contact prematurely damages the wires and shortens the life of the rope. [0002]

Another example of a fully plastic impregnated or plastic filled wire rope is disclosed in U.S. Pat. No. 4,667,462 belonging to the present applicant. In this case, the plastic material fills essentially completely all the interstices between the strands and the individual wires of the rope. Again, however, during operation of the rope, contact between the wires of the outer strands of the rope and the wires of the outer strands of the core is not prevented by such full plastic impregnation, leading to degradation and eventual premature failure of the rope. [0003]

Therefore, there is a need for an improved plastic impregnated rope in which contact between the wires of the outer strands of the rope and the wires of the outer strands of the rope"s core would be essentially prevented. [0004]

There are prior art patents that recommend placing a protective layer such as a plastic ridge or protective inserts such as plastic strips to prevent contact between the wires of the outer strands and those of the core of a wire rope. Canadian Patent No. 648,788 of Alfred Dietz discloses the ridge construction and U.S. Pat. No. 4,166,355 discloses the construction using non-metallic inserts. In both cases, however, the gaps between the outer strands of the wire rope and the strands of the core are completely blocked by such devices and thus no plastic impregnation of the rope could take place since molten plastic would not be able to flow through such ridge or such protective inserts or strips. [0005] SUMMARY OF THE INVENTION

The present invention obviates the above mentioned disadvantages and provides a plastic impregnated wire rope having a wire rope core and outer strands wound around said core, which is characterized in that said wire rope is provided with plastic bands between the core and the outer strands, said bands having such size and shape as to essentially prevent contact between the wires of the core and those of the outer strands during operation of the rope, but without substantially impeding the flow of molten plastic into and within the wire rope during plastic impregnation of said wire rope. The core of such wire rope is usually an IWRC (independent wire rope core). The resulting wire rope is a plastic impregnated rope with a controlled plastic separation between the outer rope strands and the outer core strands. [0006]

The plastic bands may be made of any suitable material that would be durable and prevent contact between the wires of the core and the outer strands. Preferred materials are thermoplastics and particularly thermoplastic elastomers of which the preferred one is polypropylene. Other materials, such as high density polyethylene, nylon, etc., can also be used and even materials such as textile strips may be suitable if properly made to prevent contact between the wires during flexing of the wire rope when it is being operated. [0007]

The bands may be of various shapes and sizes or thicknesses depending on the size and geometry of the rope. Normally, there will be as many bands as there are outer strands in the rope. Preferably, the bands have arcuate faces in contact with the outer strands, essentially matching the contour of the outer strands. [0008]

The wire rope provided with the plastic bands as described above may be fully impregnated or filled with a plastic material or only partially impregnated. In this latter case, the core may be not fully impregnated, but mostly left as a lubricated core, and/or the impregnation may not go all the way to the outer periphery of the rope. [0009]

(d) wrapping plastic bands of predetermined size and shape over the wire rope core at the entrance to the closing station, prior to winding of the outer strands around said core, said plastic bands being laid on the core so as to provide controlled plastic separation between the outer strands and the core while leaving sufficient spacing between the bands to allow flow of molten plastic therethrough; and [0014]

(e) after closing the wire rope with the plastic bands positioned between the outer strands and the core, impregnating said wire rope with a molten plastic material and subsequently allowing said plastic material to solidify. [0015]

The wire rope core is normally an independent wire rope core that is lubricated and formed with the help of a preforming head as is known in the art. The outer strands are also normally lubricated and made in a conventional manner. The closing station may consist of closing dies, again as is known in the art. The plastic bands may be guided towards the closing station and laid on the core just as the strands are being laid and closed on the core over said bands, to form the rope. To facilitate laying of the bands on the core in a proper manner, a hollow frusto-conical device may be mounted around the core, near the entrance to the closing dies, which device is connected to the performing head and rotates therewith. The device has slots on its internal surface for guiding the plastic bands towards the core and allowing them to be laid on the core in a predetermined manner, usually so as to follow the same lay as the outer strands. In this manner, when the closing of the rope has been done, the outer strands will rest on the plastic bands and will not be in contact with the core below them, the bands insuring a constant, controlled plastic separation between the outer strands of the rope and those of the core. [0016]

Once the rope is closed as described above, it is then impregnated with plastic material, for example by running it through an extrusion head as disclosed, for instance, in U.S. Pat. No. 4,609,515 which belongs to the present applicant, and the disclosure of which is incorporated hereinto by reference. Also, in lieu of a full filling of the rope as disclosed in the above patent, one may impregnate the rope only partially so that, for example, the core would not be fully impregnated or the periphery of the outer strands would be free of plastic. The impregnation would, however, exist between the outer strands and the core where the plastic separating bands are provided. The impregnation of the wire rope with plastic material need not be done right after closure of the rope. In fact, after closure, the rope may be wound on a reel and stored until the impregnation procedure is undertaken. Thus, the two procedures may take place at different times, as may be convenient to the manufacturer.[0017]

FIG. 1 shows a schematic cross-sectional view of an eight strand plastic impregnated wire rope with plastic bands between the outer strands and the core in accordance with the present invention; [0019]

FIG. 2 is a schematic longitudinal view of an arrangement for carrying out the first stage of the method of the present invention, producing a non-impregnated rope with plastic bands between the outer strands and the core; [0020]

FIG. 4 is a schematic, longitudinal, generally cross-sectional view of an extruder arrangement suitable for carrying out the second stage of the method of the present invention, namely the plastic impregnation of the rope.[0022] DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, it shows the wire rope [0024] 20 of the present invention having eight outer strands 12 and an independent wire rope core 14 with eight outer core strands 16. The wire rope 20 also has eight plastic bands 15 which prevent contact between the outer strands 12 and the outer strands 16 of the core 14. This contact is prevented not only when the rope is stationary, but also and especially when it is operational. Preferably, the bands 15 have an accurate outer surface 17 which contacts the outer strands 12, matching the rounded portion of said strands 12.

There is enough space left between the plastic bands [0025] 15 to allow molten plastic flow into and within the rope, and in the present embodiment, the rope 20 is fully impregnated with the plastic material 18.

FIG. 2 illustrates the first stage of the method of manufacturing the rope of the present invention. In this FIG. 2, a rotating performing head [0026] 22 is used to make a lubricated IWRC core 14 which is shown here in a longitudinal view rather than in cross-section as in FIG. 1. This core is moved toward the closing dies 24 as shown by arrow 23. Lubricated outer strands 12 are also made in a conventional manner and moved toward the closing dies 24 while being rotated so as to be wound around the core 14 in the closing operation. In accordance with the present invention, plastic bands 15 are wrapped onto the core 14 so as to be positioned under the outer strands 12 when the latter are wound around the core 14 on which such bands 15 have been laid. The laying of the bands 15 may be assisted by a hollow frusto-conical device 26 mounted around the core 14 and connected to the preforming head 22 by bolts 25 so as to rotate at the same speed as said preforming head 22. Device 26 has eight internal guiding slots 28 as illustrated in FIG. 3. These slots 28 guide the bands 15 so that they are laid on the core with the same lay as the outer strands and, therefore, are positioned precisely under the outer strands as they are wound on the core. This produces the first stage wire rope 10 which has all the elements of the present invention except that it is not impregnated with a plastic material.

FIG. 4 illustrates the second stage of the method of the present invention, namely the plastic impregnation. Here, the first stage wire rope [0027] 10 passes through an extrusion cross head 31 of an extruder where molten plastic is supplied through passages 32, 33, 34 as shown by the arrows. The plastic is supplied under pressure and penetrates the rope 10 between dies 36 and 37 of the extruder. The rearward flow of plastic pushes out excess lubricant 35 at the rear of the die 36 and out of the cross head 31. A third die 38 is connected by holes 39 to the atmosphere and serves to remove excess molten plastic material 18 from the surface of the impregnated wire rope 20. After leaving the extruder, the impregnated wire rope 20 is cooled to solidify the plastic material and then wound on a reel or the like, constituting the final product of the present invention.

It should be noted that other rope impregnating methods could be used which are known in the art, particularly when partial impregnation of the rope is desired. [0028]

Several samples of an 8 strand plastic impregnated wire rope were prepared, with plastic bands provided between the outer strands and the core in accordance with the present invention and compared to the same kind of plastic impregnated wire rope, but without such bands. The comparison was done by subjecting such samples to a fatigue test using a ratio of the sheave diameter to the diameter of the rope of D/d=25:1 and a load of 85,800 lbs (39,000 kg). The average of standard plastic impregnated rope samples (without bands) took 150,000 cycles to destruction, while the average of plastic impregnated wire rope samples with plastic bands between the outer strands and the core took 189,223 cycles to destruction, leading to an improvement in the life of the rope of 26.1%. This is a significant improvement obtained due to the present invention. [0029]

1. A plastic impregnated wire rope having a wire rope core and outer strands wound around said core, characterized in that said wire rope is provided with plastic bands between the core and the outer strands, said bands having such size and shape as to essentially prevent contact between the wires of the core and those of the outer strands during operation of the rope, but without substantially impeding the flow of molten plastic into and within the wire rope during plastic impregnation of said wire rope.

(d) wrapping plastic bands of predetermined size and shape over the wire rope core at the entrance to the closing station, prior to winding of the outer strands around said core, said plastic bands being laid on the core so as to provide controlled plastic separation between the outer strands and the core, while leaving sufficient spacing between the bands to allow flow of molten plastic therethrough; and

(e) after closing the wire rope with the plastic bands laid between the outer strands and the core, impregnating said wire rope with a molten plastic material and subsequently allowing said plastic material to solidify.

9. Method according to claim 8, wherein wrapping of the plastic bands over the wire rope core is done with the help of a hollow frusto-conical device mounted and rotating around the core at the entrance of the closing station, said device having slots on its internal surface for guiding the plastic bands towards the core and allowing them to be laid on the core in a predetermined manner.

15. Method according to claim 8, wherein plastic impregnation of the wire rope is carried out as a separate operation after forming the non-impregnated rope with plastic bands laid between the core and the outer strands.

Stranded wire rope or cable having multiple stranded rope elements, strand separation insert therefor and method of manufacture of the wire rope or cable

Stranded wire rope or cable having multiple stranded rope elements, strand separation insert therefor and method of manufacture of the wire rope or cable

Supplier of wire ropes and slings. The company specializes in wire rope and synthetic slings, rigging blocks, shackles, swivels, hooks and chain assemblies the oil, petrochemical, construction, marine, timber and transport industries.

This invention relates to a wire rope construction with reverse jacketed IWRC (independent wire rope core). More specifically it relates to such construction where the wire rope has no more than 18 outer strands and where the jacket consists of nylon.

Most wire ropes in the wire rope industry are designed so that outer rope strands are laid in the same direction as the strands of the core. For example, if the outer rope strands are laid to the left the same is done with the strands of the core. This is done so as to minimize contact loads between the two. In this manner the core strands do not deteriorate very quickly allowing the rope to fail first primarily from the outside. This allows users to count outer rope strands broken wires and use these as a retirement criteria for the rope. This method of making and inspecting ropes is standard in the industry and is a recognized method to use ropes in a safe manner.

Most of the ropes manufactured as described above will have a tendency to have their ends rotate under load. This is because all the strands of the rope want to straighten under load. Non-rotating ropes are a special category of ropes designed in such a way as to minimize or even prevent completely this rotation. These ropes are usually utilized in crane applications where it is not desirable to have the load rotate during lifting. The lifting end of the rope is always used unrestrained and free to rotate. If a conventional rope is used the rope will unlay, which is also undesirable.

Common designs used for these applications consist of multi strand ropes having the interior core strands laid in a direction which is opposite to the one of the outer rope strands. In these situations both the outer rope strands and the core strands want to unlay under load but they do it in opposite directions. It is a known fact in the industry that the larger the core diameter relative to the individual diameter of the outer rope strands, the better the antirotation properties of the rope. This is because the torque developed by the core can better counteract the torque developed by the outer strands of the rope.

There are three main categories of non-rotating ropes on the market: the 34-35 strand ropes with round and compacted strands; the 18 strand also with round and compacted strands; and finally there is also an eight strand, low cost and lower performance variety consisting of what is commonly known as 8 strand reverse IWRC rope.

The reason for this behaviour is quite simple: the core in the eight strand rope is the smallest of the three types described above so it does not counteract the torques of the outer strands as well as the larger cores of 18 strand, and particularly 34-35 strands. It should be noted that non-rotating wire ropes with 18 outer strands or less have generally unsatisfactory performance, with the worst cases being ropes of 8 strands or less.

Since the outer strands of these ropes cross-cut at approximately 90° angle, the outer strands of their respective cores, they usually exhibit a rapid, invisible core deterioration that cannot be detected from the outside. In other words the detection of outer broken wires cannot be used to assess the inner rope condition. This is particularly the case of 8 strands reverse IWRC ropes and also of 18 strands ropes, while this condition is less severe with the 34-35 strands ropes.

It is hence normal to retire ropes having 18 strands or less from operation after a fixed number of hours or cycles to avoid the “surprise” of a sudden internal failure. Another alternative is to jacket the core with plastic materials to prevent the abrasion taking place at the rope strand-core strand interface.

However, none of the above prior art patents deal specifically with wire ropes of 18 outer strands or less that have reverse jacketed IWRC lay, since the applicant found that with such wire rope construction the commonly employed jacket of polypropylene produces essentially no improvement over the non-jacketed construction and is therefore unsatisfactory.

When reviewing the situation it became obvious that a conventional cushioned core solution and approach did not work in this case. The examination of the polypropylene jacket showed that it had perforated at all the contact points between the outer stands and the core. A conclusion was reached that when dealing, for example, with an 8 strand rope or an 18 strand rope of reverse IWRC lay, the compression load applied by the outer strands on the core would be higher than the compression load applied by the outer strands of a 34-35 strand rope. The same would apply to all such wire ropes of 18 outer strands or less, which must therefore be considered as a special category of non-rotating ropes to which the present invention applies.

The present invention resides in providing a nylon jacket in lieu of polypropylene jacket in wire ropes having at most 18 outer strands and a reverse IWRC lay. Despite the fact that nylon has been mentioned as a suitable jacket material in the past, it was always mentioned as a substitute or alternative material to polypropylene, performing essentially the same function. It is, therefore, surprising and unexpected that in the special category of wire ropes which are under consideration herein, nylon jacketing of the core acts very differently than that of polypropylene, providing essentially double the protection as will be shown later.

FIG. 2 is a graph showing fatigue test results comparing the wire rope of the present invention with similar ropes having no jacket or a polypropylene jacket.

FIG. 1 shows a ¾″ (1.875 cm) 8×31 reverse core rope construction with eight outer strands 10, each having 31 wires. The IWRC core of the wire rope is formed of six strands 12 wound around a central strand 14. The core strands 12 are wound in the opposite direction to the outer strands 10 as shown by arrows 11 and 13. Arrow 11 indicates that the outer strands 10 of the rope are wound in the clockwise direction, while the outer strands 12 of the core are wound in the counter-clockwise direction. The core is also filled with an appropriate lubricant 15. Between the core strands 12 and the outer strands 10 there is provided an nylon jacket 16, which cushions the core against the pressure exerted by the outer stands 10 during application of the load.

FIG. 2 gives comparative results for the wire rope described above with reference to similar ropes produced without any jacket and with a polypropylene jacket of the same thickness.

Thus, the applicant first prepared a ¾″ 8 strand reverse IWRC wire rope such as shown in FIG. 1, but without any jacket between the outer stands and the core. Two samples of such rope were subjected to a reverse bend fatigue test using a load of 1000 lbs (450 kg). As shown in FIG. 2, such non-jacketed rope failed after just over 100,000 cycles.

Since polypropylene did not produce improved results one would normally have expected that nylon, which is often mentioned as an alternative to polypropylene in such cases, would also be inadequate. Applicant had used nylon in other circumstances where it was found to act in a manner similar to polypropylene. Applicant has, however, decided to try to use nylon in this particular case to see if it would enhance the performance. Two samples of the wire rope with a nylon jacket of 0.20″ (0.5 cm), such as shown in FIG. 1, where thus subjected to the same fatigue tests as the previous samples. To applicant"s surprise the number of cycles to failure essentially doubled with the nylon jacketed construction as compared to polypropylene jacketed or un-jacketed constructions. This unexpected result shows that nylon is a selected material of choice for such reverse core rope constructions.

The nylon jacket did not get perforated before the occurrence of outer rope strand degradation and failure of the wire rope due to such degradation. This was contrary to what happened with the polypropylene jacket which perforated very rapidly under load.

In stricter senses, the term wire rope refers to a diameter larger than 9.5 mm (3⁄8 in), with smaller gauges designated cable or cords.wrought iron wires were used, but today steel is the main material used for wire ropes.

Historically, wire rope evolved from wrought iron chains, which had a record of mechanical failure. While flaws in chain links or solid steel bars can lead to catastrophic failure, flaws in the wires making up a steel cable are less critical as the other wires easily take up the load. While friction between the individual wires and strands causes wear over the life of the rope, it also helps to compensate for minor failures in the short run.

Wire ropes were developed starting with mining hoist applications in the 1830s. Wire ropes are used dynamically for lifting and hoisting in cranes and elevators, and for transmission of mechanical power. Wire rope is also used to transmit force in mechanisms, such as a Bowden cable or the control surfaces of an airplane connected to levers and pedals in the cockpit. Only aircraft cables have WSC (wire strand core). Also, aircraft cables are available in smaller diameters than wire rope. For example, aircraft cables are available in 1.2 mm (3⁄64 in) diameter while most wire ropes begin at a 6.4 mm (1⁄4 in) diameter.suspension bridges or as guy wires to support towers. An aerial tramway relies on wire rope to support and move cargo overhead.

Modern wire rope was invented by the German mining engineer Wilhelm Albert in the years between 1831 and 1834 for use in mining in the Harz Mountains in Clausthal, Lower Saxony, Germany.chains, such as had been used before.

Wilhelm Albert"s first ropes consisted of three strands consisting of four wires each. In 1840, Scotsman Robert Stirling Newall improved the process further.John A. Roebling, starting in 1841suspension bridge building. Roebling introduced a number of innovations in the design, materials and manufacture of wire rope. Ever with an ear to technology developments in mining and railroading, Josiah White and Erskine Hazard, principal ownersLehigh Coal & Navigation Company (LC&N Co.) — as they had with the first blast furnaces in the Lehigh Valley — built a Wire Rope factory in Mauch Chunk,Pennsylvania in 1848, which provided lift cables for the Ashley Planes project, then the back track planes of the Summit Hill & Mauch Chunk Railroad, improving its attractiveness as a premier tourism destination, and vastly improving the throughput of the coal capacity since return of cars dropped from nearly four hours to less than 20 minutes. The decades were witness to a burgeoning increase in deep shaft mining in both Europe and North America as surface mineral deposits were exhausted and miners had to chase layers along inclined layers. The era was early in railroad development and steam engines lacked sufficient tractive effort to climb steep slopes, so incline plane railways were common. This pushed development of cable hoists rapidly in the United States as surface deposits in the Anthracite Coal Region north and south dove deeper every year, and even the rich deposits in the Panther Creek Valley required LC&N Co. to drive their first shafts into lower slopes beginning Lansford and its Schuylkill County twin-town Coaldale.

The German engineering firm of Adolf Bleichert & Co. was founded in 1874 and began to build bicable aerial tramways for mining in the Ruhr Valley. With important patents, and dozens of working systems in Europe, Bleichert dominated the global industry, later licensing its designs and manufacturing techniques to Trenton Iron Works, New Jersey, USA which built systems across America. Adolf Bleichert & Co. went on to build hundreds of aerial tramways around the world: from Alaska to Argentina, Australia and Spitsbergen. The Bleichert company also built hundreds of aerial tramways for both the Imperial German Army and the Wehrmacht.

In the last half of the 19th century, wire rope systems were used as a means of transmitting mechanical powercable cars. Wire rope systems cost one-tenth as much and had lower friction losses than line shafts. Because of these advantages, wire rope systems were used to transmit power for a distance of a few miles or kilometers.

Steel wires for wire ropes are normally made of non-alloy carbon steel with a carbon content of 0.4 to 0.95%. The very high strength of the rope wires enables wire ropes to support large tensile forces and to run over sheaves with relatively small diameters.

In the mostly used parallel lay strands, the lay length of all the wire layers is equal and the wires of any two superimposed layers are parallel, resulting in linear contact. The wire of the outer layer is supported by two wires of the inner layer. These wires are neighbors along the whole length of the strand. Parallel lay strands are made in one operation. The endurance of wire ropes with this kind of strand is always much greater than of those (seldom used) with cross lay strands. Parallel lay strands with two wire layers have the construction Filler, Seale or Warrington.

In principle, spiral ropes are round strands as they have an assembly of layers of wires laid helically over a centre with at least one layer of wires being laid in the opposite direction to that of the outer layer. Spiral ropes can be dimensioned in such a way that they are non-rotating which means that under tension the rope torque is nearly zero. The open spiral rope consists only of round wires. The half-locked coil rope and the full-locked coil rope always have a centre made of round wires. The locked coil ropes have one or more outer layers of profile wires. They have the advantage that their construction prevents the penetration of dirt and water to a greater extent and it also protects them from loss of lubricant. In addition, they have one further very important advantage as the ends of a broken outer wire cannot leave the rope if it has the proper dimensions.

Stranded ropes are an assembly of several strands laid helically in one or more layers around a core. This core can be one of three types. The first is a fiber core, made up of synthetic material or natural fibers like sisal. Synthetic fibers are stronger and more uniform but cannot absorb much lubricant. Natural fibers can absorb up to 15% of their weight in lubricant and so protect the inner wires much better from corrosion than synthetic fibers do. Fiber cores are the most flexible and elastic, but have the downside of getting crushed easily. The second type, wire strand core, is made up of one additional strand of wire, and is typically used for suspension. The third type is independent wire rope core (IWRC), which is the most durable in all types of environments.ordinary lay rope if the lay direction of the wires in the outer strands is in the opposite direction to the lay of the outer strands themselves. If both the wires in the outer strands and the outer strands themselves have the same lay direction, the rope is called a lang lay rope (from Dutch langslag contrary to kruisslag,Regular lay means the individual wires were wrapped around the centers in one direction and the strands were wrapped around the core in the opposite direction.

Multi-strand ropes are all more or less resistant to rotation and have at least two layers of strands laid helically around a centre. The direction of the outer strands is opposite to that of the underlying strand layers. Ropes with three strand layers can be nearly non-rotating. Ropes with two strand layers are mostly only low-rotating.

Stationary ropes, stay ropes (spiral ropes, mostly full-locked) have to carry tensile forces and are therefore mainly loaded by static and fluctuating tensile stresses. Ropes used for suspension are often called cables.

Track ropes (full locked ropes) have to act as rails for the rollers of cabins or other loads in aerial ropeways and cable cranes. In contrast to running ropes, track ropes do not take on the curvature of the rollers. Under the roller force, a so-called free bending radius of the rope occurs. This radius increases (and the bending stresses decrease) with the tensile force and decreases with the roller force.

Wire rope slings (stranded ropes) are used to harness various kinds of goods. These slings are stressed by the tensile forces but first of all by bending stresses when bent over the more or less sharp edges of the goods.

Technical regulations apply to the design of rope drives for cranes, elevators, rope ways and mining installations. Factors that are considered in design include:

Donandt force (yielding tensile force for a given bending diameter ratio D/d) - strict limit. The nominal rope tensile force S must be smaller than the Donandt force SD1.

The wire ropes are stressed by fluctuating forces, by wear, by corrosion and in seldom cases by extreme forces. The rope life is finite and the safety is only ensured by inspection for the detection of wire breaks on a reference rope length, of cross-section loss, as well as other failures so that the wire rope can be replaced before a dangerous situation occurs. Installations should be designed to facilitate the inspection of the wire ropes.

Lifting installations for passenger transportation require that a combination of several methods should be used to prevent a car from plunging downwards. Elevators must have redundant bearing ropes and a safety gear. Ropeways and mine hoistings must be permanently supervised by a responsible manager and the rope must be inspected by a magnetic method capable of detecting inner wire breaks.

The end of a wire rope tends to fray readily, and cannot be easily connected to plant and equipment. There are different ways of securing the ends of wire ropes to prevent fraying. The common and useful type of end fitting for a wire rope is to turn the end back to form a loop. The loose end is then fixed back on the wire rope. Termination efficiencies vary from about 70% for a Flemish eye alone; to nearly 90% for a Flemish eye and splice; to 100% for potted ends and swagings.

When the wire rope is terminated with a loop, there is a risk that it will bend too tightly, especially when the loop is connected to a device that concentrates the load on a relatively small area. A thimble can be installed inside the loop to preserve the natural shape of the loop, and protect the cable from pinching and abrading on the inside of the loop. The use of thimbles in loops is industry best practice. The thimble prevents the load from coming into direct contact with the wires.

A wire rope clip, sometimes called a clamp, is used to fix the loose end of the loop back to the wire rope. It usually consists of a U-bolt, a forged saddle, and two nuts. The two layers of wire rope are placed in the U-bolt. The saddle is then fitted to the bolt over the ropes (the saddle includes two holes to fit to the U-bolt). The nuts secure the arrangement in place. Two or more clips are usually used to terminate a wire rope depending on the diameter. As many as eight may be needed for a 2 in (50.8 mm) diameter rope.

The mnemonic "never saddle a dead horse" means that when installing clips, the saddle portion of the assembly is placed on the load-bearing or "live" side, not on the non-load-bearing or "dead" side of the cable. This is to protect the live or stress-bearing end of the rope against crushing and abuse. The flat bearing seat and extended prongs of the body are designed to protect the rope and are always placed against the live end.

An eye splice may be used to terminate the loose end of a wire rope when forming a loop. The strands of the end of a wire rope are unwound a certain distance, then bent around so that the end of the unwrapped length forms an eye. The unwrapped strands are then plaited back into the wire rope, forming the loop, or an eye, called an eye splice.

A Flemish eye, or Dutch Splice, involves unwrapping three strands (the strands need to be next to each other, not alternates) of the wire and keeping them off to one side. The remaining strands are bent around, until the end of the wire meets the "V" where the unwrapping finished, to form the eye. The strands kept to one side are now re-wrapped by wrapping from the end of the wire back to the "V" of the eye. These strands are effectively rewrapped along the wire in the opposite direction to their original lay. When this type of rope splice is used specifically on wire rope, it is called a "Molly Hogan", and, by some, a "Dutch" eye instead of a "Flemish" eye.

Swaging is a method of wire rope termination that refers to the installation technique. The purpose of swaging wire rope fittings is to connect two wire rope ends together, or to otherwise terminate one end of wire rope to something else. A mechanical or hydraulic swager is used to compress and deform the fitting, creating a permanent connection. Threaded studs, ferrules, sockets, and sleeves are examples of different swaged terminations.

A wedge socket termination is useful when the fitting needs to be replaced frequently. For example, if the end of a wire rope is in a high-wear region, the rope may be periodically trimmed, requiring the termination hardware to be removed and reapplied. An example of this is on the ends of the drag ropes on a dragline. The end loop of the wire rope enters a tapered opening in the socket, wrapped around a separate component called the wedge. The arrangement is knocked in place, and load gradually eased onto the rope. As the load increases on the wire rope, the wedge become more secure, gripping the rope tighter.

Poured sockets are used to make a high strength, permanent termination; they are created by inserting the wire rope into the narrow end of a conical cavity which is oriented in-line with the intended direction of strain. The individual wires are splayed out inside the cone or "capel", and the cone is then filled with molten lead-antimony-tin (Pb80Sb15Sn5) solder or "white metal capping",zincpolyester resin compound.

Donald Sayenga. "Modern History of Wire Rope". History of the Atlantic Cable & Submarine Telegraphy (atlantic-cable.com). Archived from the original on 3 February 2014. Retrieved 9 April 2014.