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Landmann Wire Rope Products, Inc. is a wholesale distributor of imported steel wire rope, rigging hardware, chain, cargo control and fastening materials. We have established ourselves as a market leader on the West Coast of the USA with outlets in Southern California, Northern California, the Pacific Northwest and near Omaha Nebraska.  Over the last 10+ years, we have expanded our product line to include many other products.  The key employees at Landmann bring a total of over 100 years of accumulated experience in the rigging industry to provide superlative customer service.

Our product line is basically made up of 5 main categories, Wire Rope, Chain Products, Cargo Control, Rigging Hardware and Fastening Materials which we import primarily from South Korea, China, Mexico and Japan. Within the wire rope category, we carry diameters from 3/64” to 2” in galvanized, plain and stainless steel finishes in a wide array of constructions. In the rigging hardware category, we have expanded our product line dramatically in the last few years to include a wide variety of stainless steel hardware and fastening materials to go along with our regular product line. This diverse product line allows us to supply our customers who service a wide range of industries including, logging, fishing, mining, industrial, construction and architectural to name a few. This diversification of rigging hardware as well as the range of wire rope, cable and chain products allows us to better serve you, the customer as a one stop shop for all your wire rope and rigging needs.

Our three warehouse locations along the West Coast, USA are in Santa Fe Springs, California, Vacaville California and Fife, Washington.  We also have a distribution center near Omaha, Nebraska.  This allows us to serve our customers better by shipping most orders the same day for quick deliveries. We also specialize in direct mill shipments that come from the factory directly to you whether our customers are located on the East Coast USA, or in Europe.

One final note about Landmann Wire Rope Products. We realize the importance of being different than our competitors. We strive to make your experience with Landmann one where you feel that we are a part of your success and that you can count on Landmann to fulfill your needs, whether they are big or small. Customized and professional client service is a mainstay at Landmann.

Use our thorough list of wire rope manufacturers and suppliers in California to examine and sort top wire rope manufacturers with previews of ads and detailed descriptions of each product. Any wire rope manufacturers can provide wire rope products to meet your company"s specific qualifications. An easy connection to reach wire rope manufacturers through our fast request for quote form is provided as well. This source is right for you whether it"s for cable railing, marine rigging, or any other wire rope needs.

Wire ropes can be seen everywhere around us, they are made of strands or bundles of individual wires constructed around an independent core, suitable for construction, industrial, fitness, commercial, architectural, agricultural, and marine rigging applications.

Wire rod is made from high carbon steel wires(0.35 to 0.85 percent carbon) in a hot rolling process of a required diameter, usually from 5.5mm to 8 mm.

Wire rod is drawn to the required diameter by the 1st drawing machine after descaling dust and rust, adding mechanical properties suitable for application.

Positioning the wires different or the same size lay in multiple layers and same direction, or cross lay and diameter is maintained by one-third of the rope size.

So in theory, it is very simple to manufacture wire ropes. However there are many more details that must be closely monitored and controlled, and this requires time and experienced personnel since it is a super complicated project you cannot imagine.

We strive to create premium products in a class all their own, but we believe our global impact is so much bigger than that. Press play to learn what makes WireCo a world ahead of other companies.

Ropeblock hardware is found worldwide wherever key components in crane systems are in contact with the wire rope. Our products are designed to contribute to consistent safety and efficiency in any type of lifting & rigging application. We have extensive knowledge of blocks, sockets, and rigging gear, with unique value being added by our Smart Engineering approach. This combination is our key to providing solutions that deliver. We manufacture and globally distribute thousands of blocks and tens of thousands of sheaves and sockets a year. In addition we offer smart warehousing and logistics services.

BC Wire Rope & Rigging is a full service provider of wire rope, slings, chain, hoists, and rigging equipment. BC Wire Rope has served the heavy lifting needs of customers throughout Los Angeles, San Diego, Las Vegas, Tucson and the Western United States since 1974. Specializing in lifting products ranging from fall protection to synthetic slings, BC Wire Rope & Rigging carries products from the industry’s most reputable vendors including Crosby, Slingmax, Campbell, and Bridon American. With ample testing and manufacturing capabilities, BC Wire Rope is also the manufacturer of KWIK synthetic slings.

BC Wire Rope was onsite as the last steel beam was raised by Schuff Steel at the new, future home of the Los Angeles Rams and LA Chargers at SofFi Stadium in Inglewood, California. The raising of the last beam is marked by the raising of a ceremonial Christmas Tree, […]

Established nearly 40 years ago in Southern California, BC Wire Rope now manufacturers and distributes wire rope from 5 locations to strategically serve customers across the West Coast. Headquartered in a 35,000 square foot warehouse and manufacturing facility in Anaheim, BC Wire Rope is the premier provider of rigging throughout the greater Orange County and Los Angeles area and also has branches in Tucson, Las Vegas, San Diego, and Elko. These locations allows BC to stock a full inventory of specialty lifting products and enables BC to efficiently meet a wide range of manufacturing needs.

Full in-house testing and wire rope manufacturing capabilities help ensure that BC Wire Rope can meet or exceed its customers’ needs. BC Wire Rope can press wire rope slings and swaged boom pendants, splice slings and soft rope, and can fabricate special end fittings. BC also manufacturers its own line of synthetic slings through its KWIK Products division. KWIK Products include nylon eye & eye endless flat slings, high performance fiber slings, polyester round slings, and choker and basket hardware slings. BC Wire Rope also provides customers with proof testing through use of its 4 test beds that can test slings, blocks, and hardware with up to 1 million pounds of force.

BC Wire Rope & Rigging’s unrelenting focus on customer service and industry leading products is evidenced by its ‘Quality – No Compromise’ motto. BC Wire Rope has been a proud member of the wire rope industry’s trade association—Associated Wire Rope Fabricators (AWRF)—for over 35 years. The commitment to longstanding industry relationships is also demonstrated by the fact the more than half of BC Wire Rope’s employees have remained with the company for over 18 years.

With years of industry knowledge and a full product inventory, chances are that BC Wire can meet your lifting needs. Contact the specialists at BC Wire Rope today to find out more about what BC Wire Rope can do for you.

Look to Enidine for high performance Wire Rope Isolators and Compact Wire Rope Isolators. The wire rope isolators have stainless steel cable and RoHS compliant aluminum retaining bars, which provides excellent vibration isolation. The isolators are corrosion resistant, which makes them environmentally stable and high-performance in a variety of applications. The isolators are completely unaffected by oil, chemicals, abrasives, ozone, and temperature extremes.

The compact wire rope isolator is smaller than a traditional wire rope and can absorb shock and vibration in small spaces. Single point mounting offers flexibility for integration into existing products.

Both compact wire rope isolators and wire rope isolators can be used on galley components where motors and fans produce vibrations onto surrounding structures. They can also be used to control vibration and thermal expansion.

They say you should never visit the sausage factory, and that may be true, but the wilfully ignorant are not to be trusted, and steel wire rope is certainly a special type of sausage. It was a visit that put me through the emotional spectrum, from disinterested to bemused, to bewildered, and finally awed at the sheer scale of the operation. It’s a little bit like when you find out where babies come from: Horrifying and weird to begin with, but before long you find yourself utterly fascinated…

Flexible steel wire rope has been one of the mainstays of heavy industry for more than a hundred years. Whether you want to lash down scaff planks, carry out lifting and cranage, use draglines for surface mining, or even pull down a massive statue of Saddam Hussein, wire rope has thousands of applications.

The Wirerope Works factory in Williamsport, Pennsylvania has a long history of producing this essential component of progress in the 20th century, and although cheaper imports from China and India continue to flood the market, the caretakers of the Bethlehem Wire Rope brand are still proud to produce a product of the highest quality on local labour and quality materials.

Based in Lycoming County in Pennsylvania, Wirerope Works (WRW) began its life as the Morrison Patent Wire Rope Company in 1886. The original mill was built upstream on the banks of the Susquehanna River to service the softwood logging industry, however regular flooding led to the relocation and inevitable expansion of the factory in the town of Williamsport.

The design and manufacture of steel wire rope was no longer in its infancy at that stage. The first practical use of steel rope in 1834 was credited to a German mining official named Wilhelm August Julius Albert, who worked at the Clausthal silver mines in Saxony.

Up until that point, all mining haulage was done with hemp fibre rope or chains. In the humid, damp conditions of an underground mine, moisture would cause the ropes to perish from rot, the gradual deterioration reducing their load bearing capacity, so they required frequent replacement.

That first incarnation of modern steel wire rope was extremely effective for heavy haulage, and much more reliable than rope or chain. Albert Rope, as it came to be known, was a simple construction of three 3.5mm gauge wrought-iron wires, hand-wound into strands, with three or four of those strands wound into a single rope. However, Albert rope lacked the flexibility of rope or chain, meaning it couldn’t be drawn through a pulley sheave, and its use stopped in the 1850s.

But the idea for wire rope had already caught on in England, where thinner wires were woven around a fibre core, with six of those strands woven around a central fibre core, resulting in a more flexible product. This design, as well as a mechanical system for its construction (called a strander), was patented by Robert Newall, who brought the new technology to America, and the boom-time economy of the California Gold Rush.

However, it was in Pennsylvania where a German-born engineer and surveyor named John Roebling began to develop ropes which were entirely constructed of wire. Roebling used a 6/19 construction (6 strands; 19 wires per strand). A strand built of 19 wires of the same gauge resulted in a hexagonal profile, and desiring a round shape Roebling conceived of using three different gauges of wire to achieve that result. The effect of this was to reduce the space inside the rope, tightly packing the wires together, which gave the rope greater stability under load.

With massive demand for coal haulage in Pennsylvania, as well as cable car applications for public transportation, and most importantly civil engineering projects to service, Roebling set up a wire rope factory in 1849 in Trenton, New Jersey. But he wasn’t the first to invest in a factory like that: Other people had the same idea, and wire rope mills were starting to pop up around the United States. In only 14 years wire rope had gone from a hand-made experiment in a German silver mine, to a globally recognised tool of industry with high demand for scaled-up production.

If Roebling had any hubris about cashing in on this amazing new invention, you could be forgiven for thinking it was a little dampened when his arm and shoulder were horrifically mangled in an accident with one of his stranding machines. But it would seem that Roebling’s interest in wire rope was not strictly for profit, however, as he had for some time harboured a bit of an obsession with sketching suspension bridges. He was a big fan of the expansionist philosophy of Manifest Destiny, and had been very keen on establishing a utopian settlement called Germania (now the town of Saxonburg), where people like him trying to escape the brutal oppression of post-Prussian War Europe could be free to make sauerkraut and smoked pork products, unmolested by the authorities.

But Roebling recovered from his injuries, his factory continued to produce wire rope, and he designed and built a number of suspension bridges using his own product right up until he began design work for the Brooklyn Bridge. Unfortunately, Roebling managed to get his foot crushed by a ferry while standing on a dock trying to work out where the bridge should go. He died of tetanus 24 days later, but his son Washington went on to complete the Brooklyn Bridge project, while his son Charles would invent an 80 tonne wire rope machine.

By 1886, the year the Brooklyn Bridge was opened, a venture like setting up a wire rope factory in Pennsylvania was not at all a bad way to invest $100,000 (probably about $US3 million today), and that is precisely what three businessmen from Williamsport did.

Morrison Patent was changed to the Williamsport Wire Rope Company in 1888, manufacturing steel and galvanised wire rope “from one-eighth of an inch to two and one-half inches in diameter, and any length up to two miles in one continuous piece”, according to an 1892 history of Lycoming County.

The lumber boom in Lycoming peaked in 1891, and the neighbouring Indiana County saw a coal-mining boom start in 1900, so the industrial economy was perfect for the growth of the Williamsport rope mill. A new wire mill was built in 1916, and the current rope mill was built in 1928, which was pretty poor timing considering the Great Depression would start the next year.

By 2004, the Williamsport site had been bought and sold a number of times, changing company names like a serial divorcee, acquiring assets from other defunct companies such as Roebling Wire Rope (the company started by John Roebling in 1849) but always keeping the Bethlehem Wire Rope brand, which became synonymous with top quality steel cable, and is still proudly emblazoned on their rope spools to this day.

In 2002 Williamsport Wirerope Works bought out the bankrupt Paulsen Wire Rope, a rope mill located in nearby Sunbury, and continued to produce under the Paulsen name. But by 2003 the company was also in financial strife, and the management were looking for another buyer who could bail out the company and keep the 600,000 square foot Bethlehem factory running.

The US wire rope manufacturing industry had changed dramatically over the course of 100 years. From an exciting new industry that would allow explosive growth in the productivity of coal mining through the development of dragline surface mining operations in the early 20th century, as well as enabling some of the biggest civil engineering projects ever seen since the Pyramids of Giza, the US stable of 27 wire rope companies had been consolidated down to just three names: Bridon, WireCo, and Bethlehem.

Bridon is another Pennsylvania company, based 100 kilometres away in Wilkes-Barre. Unlike Williamsport which remained a local manufacturer, Bridon expanded rapidly, acquiring other wire rope companies and branching out across the world, developing into a massive, multinational conglomerate, as did WireCo Worldgroup.

With two global entities for domestic competition, Bethlehem also faced increasing pressure from low-cost offshore wire rope producers in countries like China, Korea and India.

Present executive vice-president Lamar J Richards remembers circumstances were looking grim for the Bethlehem brand and for the local employees, with a bid for takeover by Pennsylvania, USA and world market rival WireCo Worldgroup in late 2003.

“Instructions from the ownership at the time were, because we were about to be bought by a competitor we really weren’t going to be making wire, so we had to get rid of all the raw material, the rod, our starting point for the wire,” he said.

But I didn’t know any of those things when I found myself standing, probably in the same spot as Mr Saltsgiver did when starting his tour, right there in the foyer of the single largest wire rope manufacturing facility in North America on a muggy Thursday morning. I had arrived at the factory with a junket of assorted journalists, exhausted from touring a gamut of other factories and fighting off a particularly vicious head cold, quite oblivious to the fact that our tour bus had, having dropped us off, already left with my camera bag still on board. Perhaps one could have forgiven me for being a little out of sorts at first. But not for long…

Walking into the front offices of Wirerope Works on Maynard Street, it’s clear there’s pride in the product here. Foot-long samples of rope in varying configurations and gauges lie on polished timber plinths in the foyer, cleaned of oil with sharp edges ground smooth for safe handling by visitors.

On the walls hang photographs of major construction projects which were supplied with Bethlehem brand wire rope: Madison Square Gardens, the restringing of the Brooklyn Bridge, the Niagara Falls tightrope.

Lamar J. Richards, the executive vice president of Wirerope Works, explains to us some of the history of the plant (see Australian Mining February 2016), but one of the most touching stories he tells us is about how the present owner, Tom Saltsgiver, came to buy the company and keep it alive for the sake of the local economy in Williamsport.

As it turned out, the newly renamed Wirerope Works became profitable after 18 months of capital support. Shortly after that, the housing bubble burst.

One of the first things shown to us is the floor. The factory is tiled with timber bricks, grain pointing upward and creating a very unique effect where the timber had been polished by decades of wear. The timber floors are a result of Williamsport’s logging history, when wooden blocks were cheap and readily available in bulk. To this day when any flooring needs repairs or replacement, Wirerope Works still uses the original material. To walk on it is remarkably different from concrete, and where I can compare the two it is noticeably easier underfoot. Bear in mind the factory is 620,000 square feet, so a lot of what essentially was scrap lumber had been put to good use.

First we are shown the raw material: 4mm steel wire in loose looking coils about 6 foot across, lifted by forklifts and taken through to a hydrochloric acid bath which will strip off any contaminants. Having been battling a common cold for a few days, I didn’t need to be told the fizzing pool before me was acid. Plumes of vapour were pouring off the bath, and before I could think of doing anything about it the congestion in my head loosened and poured down the back of my throat, and I suddenly I could breathe more clearly and easily than I had done for days! I realised it was the corrosive vapour that had cleared my head, and it might soon start to work on the tissues of my sinus. I tried to hold my breath while our host laughed and tried to explain, incoherently over the roar of the factory, the process of treating the raw material.

We all back away from the deadly head-cold cure and are led to the furnace, where 12 of the washed coils are set up to feed wire through an oven blazing at 1000 degrees Celcius, only 360 degrees shy of melting point. I realise wearing my jacket, despite the cool Pennsylvania humidity, was not the smartest thing in the world to do and we walk past the contained inferno, pouring with sweat.

It’s becoming amply clear to me that this is an extremely dangerous workplace, and we continue to the other side of the furnace where the cherry glowing wires are fed down into a simmering oil bath for quenching.

We file past, only a couple of feet from the long vat of hellbroth with no rails or guards and I think to myself, ‘this must be the single most dangerous thing I have ever stood near’. Having been a labourer and rigger for most of my adult life, I have certainly worked in some unsafe conditions, from high rise buildings with no fall arrest equipment to a uranium mine with no proper PPE, but even those experiences didn’t seem to come close to standing next to this long vat of near-boiling oil. What would happen if one of us stumbled, reaching out for grip and finding only oil that could burn off a limb in seconds, or worse, what if one could fall in altogether! I reassured myself a victim of clumsiness would pass out almost instantly from the shock of the burn. Small comfort as we tried to stay as far away from the vat as possible, with a few feet of leeway for space.

Once cool enough, the wire passes through hydrochloric acid to wash off all traces of contaminant, and I hold my breath as we walk the length of the pool, our host taking deep breaths as if it were fresh spring air and not lung melting fumes, laughing as he watches the visitors squirm… Does he know something I don’t? I sure hope so.

A coating of zinc phosphate, another rinse, and another final coating prepares the wire for extrusion, which has two key functions. The most obvious is for achieving the correct gauge of wire required for twisting into the various rope products, but extrusion also means the steel wire is stretched to align the structure of the steel to align in a single direction, which strengthens and increases the breaking strain of each wire.

However, the most important part of all of this is the stranding process, and here is where my reactions turn from shock to awe. As a rigger using steel wire rope on a daily basis for slinging, I had often wondered how the rope was produced, and here it was before my eyes: The factory floor – acres of it – was full of lines of planetary stranders, all with sets of wires in large bobbins, as many as 64 wires on a single machine, feeding into a single, oily strand of rope. The factory had machines of all sizes hard at work, furiously spinning to produce the some 1200 different combinations of wire rope that come out of the factory every three months.

Finally, we come to the heart of the factory: We stand, astonished, gazing up at the 12 foot tall, 800 tonne closing machine, designed to produce the 7 inch rope for dragline boom pendants, and construction cable like that used to build the Brooklyn Bridge. The already huge strands are all dragged into a central point, slowly weaving the helical pattern of wires around a hefty centre rope into a single massive cable which will one day end up on a dragline somewhere in the world.

With a history spanning 120 years, the Wirerope Works factory has seen plenty of hard times, but it’s also had a lot of luck. With good leadership at the helm from the likes of Saltsgiver and Richards, and ongoing demand for steel wire rope, the old Williamsport factory could continue to produce its quality bespoke products for another 120 years.

Consistently developing steel wire products that meet the highest quality standards has made us a strong partner of the automotive industry. Customers engage and co-create with us in our common quest for solutions that address ecological, safety and performance trends.

Thanks to the technology of coated high carbon flat spring wire a next generation window wiper was developed based on 6 parts instead of 23 parts with 50% weight reduction and better aerodynamic behavior.

Consumer goods require increasingly higher standards for quality, ecology and comfort. The demand for more advanced steel wire products evolves accordingly. Often unknown, but always there - our solutions are a part of the products we all use every day.

Fencing, guiding, and tensioning solutions combine our product and service offering to the agricultural sector, while our heavy-duty steel ropes are used in fishery and forestry. The story of Bekaert started in 1880 with barbed wire and has continuously grown from these roots.

At CERTEX USA, we set the standard for rigging supplies, lifting products and world-class fall protection as well as the top industrial rescue courses and critical testing services. Many companies and workers around the country rely on our expansive line of quality lifting equipment and products. From wire rope to wire mesh slings, to hoists, clamps, blocks and sheaves, CERTEX USA has the lifting equipment you will need to get the job done correctly, safely and on schedule. When it comes to rigging equipment, supplies and lifting products, you shouldn’t have to worry about choosing between the highest-quality products available and the products offered at affordable prices. At CERTEX USA, we have you covered with quality lifting products at competitive prices.

Wire rope and cable are each considered a “machine”. The configuration and method of manufacture combined with the proper selection of material when designed for a specific purpose enables a wire rope or cable to transmit forces, motion and energy in some predetermined manner and to some desired end.

Two or more wires concentrically laid around a center wire is called a strand. It may consist of one or more layers. Typically, the number of wires in a strand is 7, 19 or 37. A group of strands laid around a core would be called a cable or wire rope. In terms of product designation, 7 strands with 19 wires in each strand would be a 7×19 cable: 7 strands with 7 wires in each strand would be a 7×7 cable.

Materials Different applications for wire rope present varying demands for strength, abrasion and corrosion resistance. In order to meet these requirements, wire rope is produced in a number of different materials.

Stainless Steel This is used where corrosion is a prime factor and the cost increase warrants its use. The 18% chromium, 8% nickel alloy known as type 302 is the most common grade accepted due to both corrosion resistance and high strength. Other types frequently used in wire rope are 304, 305, 316 and 321, each having its specific advantage over the other. Type 305 is used where non-magnetic properties are required, however, there is a slight loss of strength.

Galvanized Carbon Steel This is used where strength is a prime factor and corrosion resistance is not great enough to require the use of stainless steel. The lower cost is usually a consideration in the selection of galvanized carbon steel. Wires used in these wire ropes are individually coated with a layer of zinc which offers a good measure of protection from corrosive elements.

Cable Construction The greater the number of wires in a strand or cable of a given diameter, the more flexibility it has. A 1×7 or a 1×19 strand, having 7 and 19 wires respectively, is used principally as a fixed member, as a straight linkage, or where flexing is minimal.

Selecting Wire Rope When selecting a wire rope to give the best service, there are four requirements which should be given consideration. A proper choice is made by correctly estimating the relative importance of these requirements and selecting a rope which has the qualities best suited to withstand the effects of continued use. The rope should possess:Strength sufficient to take care of the maximum load that may be applied, with a proper safety factor.

Strength Wire rope in service is subjected to several kinds of stresses. The stresses most frequently encountered are direct tension, stress due to acceleration, stress due to sudden or shock loads, stress due to bending, and stress resulting from several forces acting at one time. For the most part, these stresses can be converted into terms of simple tension, and a rope of approximately the correct strength can be chosen. As the strength of a wire rope is determined by its, size, grade and construction, these three factors should be considered.

Safety Factors The safety factor is the ratio of the strength of the rope to the working load. A wire rope with a strength of 10,000 pounds and a total working load of 2,000 pounds would be operating with a safety factor of five.

It is not possible to set safety factors for the various types of wire rope using equipment, as this factor can vary with conditions on individual units of equipment.

The proper safety factor depends not only on the loads applied, but also on the speed of operation, shock load applied, the type of fittings used for securing the rope ends, the acceleration and deceleration, the length of rope, the number, size and location of sheaves and drums, the factors causing abrasion and corrosion and the facilities for inspection.

Fatigue Fatigue failure of the wires in a wire rope is the result of the propagation of small cracks under repeated applications of bending loads. It occurs when ropes operate over comparatively small sheaves or drums. The repeated bending of the individual wires, as the rope bends when passing over the sheaves or drums, and the straightening of the individual wires, as the rope leaves the sheaves or drums, causing fatigue. The effect of fatigue on wires is illustrated by bending a wire repeatedly back and forth until it breaks.

The best means of preventing early fatigue of wire ropes is to use sheaves and drums of adequate size. To increase the resistance to fatigue, a rope of more flexible construction should be used, as increased flexibility is secured through the use of smaller wires.

Abrasive Wear The ability of a wire rope to withstand abrasion is determined by the size, the carbon and manganese content, the heat treatment of the outer wires and the construction of the rope. The larger outer wires of the less flexible constructions are better able to withstand abrasion than the finer outer wires of the more flexible ropes. The higher carbon and manganese content and the heat treatment used in producing wire for the stronger ropes, make the higher grade ropes better able to withstand abrasive wear than the lower grade ropes.

Effects of Bending All wire ropes, except stationary ropes used as guys or supports, are subjected to bending around sheaves or drums. The service obtained from wire ropes is, to a large extent, dependent upon the proper choice and location of the sheaves and drums about which it operates.

A wire rope may be considered a machine in which the individual elements (wires and strands) slide upon each other when the rope is bent. Therefore, as a prerequisite to the satisfactory operation of wire rope over sheaves and drums, the rope must be properly lubricated.

Loss of strength due to bending is caused by the inability of the individual strands and wires to adjust themselves to their changed position when the rope is bent. Tests made by the National Institute of Standards and Technology show that the rope strength decreases in a marked degree as the sheave diameter grows smaller with respect to the diameter of the rope. The loss of strength due to bending wire ropes over the sheaves found in common use will not exceed 6% and will usually be about 4%.

The bending of a wire rope is accompanied by readjustment in the positions of the strands and wires and results in actual bending of the wires. Repetitive flexing of the wires develops bending loads which, even though well within the elastic limit of the wires, set up points of stress concentration.

The fatigue effect of bending appears in the form of small cracks in the wires at these over-stressed foci. These cracks propagate under repeated stress cycles, until the remaining sound metal is inadequate to withstand the bending load. This results in broken wires showing no apparent contraction of cross section.

Experience has established the fact that from the service view-point, a very definite relationship exists between the size of the individual outer wires of a wire rope and the size of the sheave or drum about which it operates. Sheaves and drums smaller than 200 times the diameter of the outer wires will cause permanent set in a heavily loaded rope. Good practice requires the use of sheaves and drums with diameters 800 times the diameter of the outer wires in the rope for heavily loaded fast-moving ropes.

It is impossible to give a definite minimum size of sheave or drum about which a wire rope will operate with satisfactory results, because of the other factors affecting the useful life of the rope. If the loads are light or the speed slow, smaller sheaves and drums can be used without causing early fatigue of the wires than if the loads are heavy or the speed is fast. Reverse bends, where a rope is bent in one direction and then in the opposite direction, cause excessive fatigue and should be avoided whenever possible. When a reverse bend is necessary larger sheaves are required than would be the case if the rope were bent in one direction only.

Stretch of Wire Rope The stretch of a wire rope under load is the result of two components: the structural stretch and the elastic stretch. Structural stretch of wire rope is caused by the lengthening of the rope lay, compression of the core and adjustment of the wires and strands to the load placed upon the wire rope. The elastic stretch is caused by elongation of the wires.

The structural stretch varies with the size of core, the lengths of lays and the construction of the rope. This stretch also varies with the loads imposed and the amount of bending to which the rope is subjected. For estimating this stretch the value of one-half percent, or .005 times the length of the rope under load, gives an approximate figure. If loads are light, one-quarter percent or .0025 times the rope length may be used. With heavy loads, this stretch may approach one percent, or .01 times the rope length.

The elastic stretch of a wire rope is directly proportional to the load and the length of rope under load, and inversely proportional to the metallic area and modulus of elasticity. This applies only to loads that do not exceed the elastic limit of a wire rope. The elastic limit of stainless steel wire rope is approximately 60% of its breaking strength and for galvanized ropes it is approximately 50%.

Preformed Wire Ropes Preformed ropes differ from the standard, or non-preformed ropes, in that the individual wires in the strands and the strands in the rope are preformed, or pre-shaped to their proper shape before they are assembled in the finished rope.

This, in turn, results in preformed wire ropes having the following characteristics:They can be cut without the seizings necessary to retain the rope structure of non-preformed ropes.

They are substantially free from liveliness and twisting tendencies. This makes installation and handling easier, and lessens the likelihood of damage to the rope from kinking or fouling. Preforming permits the more general use of Lang lay and wire core constructions.

Removal of internal stresses increase resistance to fatigue from bending. This results in increased service where ability to withstand bending is the important requirement. It also permits the use of ropes with larger outer wires, when increased wear resistance is desired.

Outer wires will wear thinner before breaking, and broken wire ends will not protrude from the rope to injure worker’s hands, to nick and distort adjacent wires, or to wear sheaves and drums. Because of the fact that broken wire ends do not porcupine, they are not as noticeable as they are in non-preformed ropes. This necessitates the use of greater care when inspecting worn preformed ropes, to determine their true condition.