Trawlers

Wire Rope Goes Fishing

Photo: Sunrise greets a line of fishing trawlers at their moorings in Barnegat Light, NJ. Photo © Cwieders | iStockphoto

Commercial fishing trawlers take on a time-honored tradition by utilizing modern fishing year in the form of wire rope.

Wire Rope Goes Fishing

by Al Pirozzoli

Published in the June 2020 issue of Wire Rope News & Sling Magazine

If anyone has faced the unnerving wrath of King Neptune, it’s the commercial fishing fleets that venture out on dangerous seas to bring back the fruit of the ocean. Whether it’s king crabs, tuna or any assortment of the sea’s bounty, someone must have the courage to face the rigors of the deep. Courage and experience are necessary and so is the equipment.

When it comes to hoisting up a catch. it’s about the basics, which are often overlooked and disappear in plain sight because we take them for granted. Without the basics in place not much production takes place. If you think about it, most sports championships are won with fundamentals. Of course, we love to see the flying dunk, and the hat-trick. But games are usually won with a field goal or foul shot: the basics. It’s an obvious point when you consider the implications. The most powerful bullet train goes nowhere without rails; The most luxurious Porsche sits in place without tires; Computers are useless without electricity.

It’s no different on a commercial fishing vessel. In that case, one of the key fundamentals that comes into to play when bringing up the nets or baskets, are the wire rope cables that make the lifting work reliably, over and over. This is especially true on long distance fishing expeditions much like what we see on TV shows such as “Deadliest Catch,” and “Wicked Tuna.” When you’re “way out there,” you can’t afford to lose a catch because a wire rope fails. It’s the fundamentals, the basics that make for success. Whatever type of hoist, crane or the latest technology system is used on a boat, something must do the work of pulling up the catch, and that’s where wire rope comes into the picture.

The total number of fishing vessels in the world was estimated to be about 4.6 million in 2016. The earliest fishing boats where pretty basic; dugout canoes, crude vessels covered with reeds and tar to keep them watertight and, very simple rafts. In archaeological excavations going back thousands of years, Neolithic dugout canoes have been discovered. Early crafts were unsuitable for distance fishing and hunting and only capable of staying near shorelines.

From the earliest days of fishing for food to the vessels that work commercially today such as “Factory Ships,” or Fish Processing Vessels that catch, process and freeze in one system, wire rope still holds preeminence in hoisting things up and out of the sea. Without that basic in place you return to port with nothing but wet, empty nets. It’s wire rope that brings in the bounty regardless of the various forms of nets and baskets. Nets or baskets are submerged in place and at the right time the boat returns, navigating along their traffic pattern and raise their catch.

Nets can also be let down and then raised to capture crustaceans and fish as they hoist the nets up to the surface. There are hand-operated lift nets, hoop and blanket nets, dustpans, baskets, and stationary types used along the shoreline. Each of these methods hold one thing in common; they employ some type of wire rope to bring up the catch!

Robert Stirling Newall improved the rope manufacturing process around 1840, featuring three strands of four wires. Wire rope manufacturing in the United States kicked off in 1841 with John A. Roebling (John A. Roebling’s Sons Company).

Wire rope became the key to Roebling’s success in building suspension bridges (learn more at the Roebling Museum in Roebling, New Jersey). Due to its durability and superiority to other rope forms such as ropes manufactured with metal chains saw demand for the product rise quickly.

FROM PALEOLITHIC TIMES

Fishing is an ancient art dating back to the Upper Paleolithic period. Archeologists discovered 40,000-year-old human skeletal remains from Eastern Asia. The remains were shown to be a consumer of freshwater fish, an important staple in daily diets. During that time period most people were hunter-gatherers and tended to be nomadic (they followed the food). The settlements that were found almost always showed evidence that fishing was a major food source. Native Americans, from 7,500 to 3,000 years ago, fished along the California coast were using gorge hook and line tackle.

On India’s Andaman Islands, aboriginal people used harpoons harnessed with long cords for fishing from earliest times. The point is obvious; as far back as these time periods go, people fished, and they figured out ways to bring in the fish which in many cases required a fashioned rope of some kind; the precursor to today’s wire rope. In all these cases we recognize that regardless of levels of sophistication and fishing skills, some form of rope or line served as the basics that made it all work.

FROM LAKES, PONDS AND INLETS TO THE SEA

In modern times none of the predecessor forms of rope or line would be capable of managing out on the high seas. This is precisely why marine wire rope in its varied forms is best suited for the fishing industry. It’s designed with good corrosion resistance, high tensile strength, consistent dimensions for reduced pulley wear and increased abrasion resistance. Industrial fishing ropes are constantly exposed to wear and abrasion, especially trawling ropes used in purse seining, (a large seine, or net, is set in the water by two boats that surround a school of fish. The task is to arrange the boats, so the ends of the nets are brought together and closed around the fish).

Wire rope applications at sea are exposed harsh conditions of salt water and other forms of moisture. Stainless steel wire rope stands up to the vigorous corrosive and abrasive attack of the ocean. Industry studies have shown that commercial fishing is the most dangerous profession, even more hazardous than coal mining. While deaths are rare, it is still easy to lose a finger, break an arm, or get bashed in the head with all the hooks, lines, hydraulics, and heavy equipment in use on the rolling wet deck of a fishing vessel. The equipment that helps them succeed can also hurt them in many ways. Therefore, diligent maintenance and solid safety precautions are vital.

THE BUSINESS END OF WIRE ROPE


Photo: Rick Boiteau of Trawlworks splices a new eye in a fishing boat’s tow wire.

Wire ropes are used in hoisting up the catch at sea and then wound back up on the trawler’s drums on deck unused the rest of time. Because of this, corrosion is a big concern so the higher the zinc level the better. Some boats switch back and forth between entirely different fisheries for crabbing, fishing and scalloping, and therefore use entirely different types of wire rope for each. When out scalloping they use larger wire, and for longer seasons of the year their other wire is stored on a reel.

This inactive storage is the worst situation corrosion-wise. Scallopers however, tend to be harder on wire rope because of the nature of how they do things. They haul back and set in, many times throughout a trip. Trawlers on the other hand generally do not — they work in longer tows. Galvanized wire, when used in salt water, can then be wound up and stored for long periods of time. To help against corrosion, wire rope should be lubricated as its wound up on the reel to help with corrosion.

According to Steve Taber, General Manager of Trawlworks, Inc., in Narragansett, Rhode Island, a supplier and distributor of wire rope, hardware, trawl doors and rigging supplies for the commercial fishing industry, “Tow wire and wire rope are used for running and standing rigging. More and more we see rigging made of stainless-steel wire rope instead of galvanized.

“A galvanized stay will typically last many years, but if you want to pay the extra cost up front, a stainless-steel stay will last forever. Galvanized and stainless-steel wire rope is used for bridles and ground cables and on the trawls we make. Like the stays, there’s been more and more use of stainless-steel wire rope instead of galvanized in all these applications. A typical customer has many nets and different types of gear and is switching back and forth constantly. It’s the time tow rope spends dormant that makes corrosion the worst.”

IT’S ABOUT CHOICE AND CAPACITY

Wire rope will continue to perform with care and maintenance. However, depending on the type of fishing it can be placed under great stress and in some situations can be abused. If the diameter is smaller than other fishing boats typically use in their horsepower and gear range, they don’t hold up as well, and if it’s larger diameter than typically used it’s the opposite. Each boat requires a specific diameter for their tow wire.

The larger the boat and bigger the horsepower the larger gear they’ll be towing which requires a larger diameter wire rope. A boat typically settles on one wire size and stays with that for as long as they own their boat.

Typically, new tow wire is purchased every one or two years, but they don’t replace it entirely; only the oldest on the outside of their hoisters/drums is what gets used the most. Longevity is also a factor based on the material used in wire rope. Other forms of rope material are being manufactured as well.

“We’re just starting to see some synthetics. The initial cost is a big hurdle to overcome as it can be 2-3 times as much as traditional wire rope. But it’s so much lighter which is a major benefit. Less weight allows the fishing boat to more easily move their gear around and the added benefit is that they save on fuel. Plus, it obviously doesn’t rust out. We think that if you take care of it and it doesn’t get cut or chaffed out, it will probably last longer as well,” said Taber.

Most of the wire rope Trawlworks sells for tow wire is compacted. It costs more initially but it’s stronger and holds up better over time. The smaller sizes, from 7/16″ and down is just round strand for their customers, as the initial cost doesn’t justify the benefits for these small sizes. The larger diameter wire ropes a boat uses the longer it will last. This must be balanced with capability. Correct choices are crucial, for instance, how well can the boat tow and move around using larger diameter wire ropes, and will it even fit on their hoister/drum?

WIRE ROPE TLC

A little tender love and care always goes a long way to keep things operational, so maintenance is at the forefront. Steve Taber addressed that issue. “The fishermen always have to inspect their tow wire and as it wears out, they will ‘cut back’ or cut off the oldest wire. We will usually perform this service for them. We come down to the boat, pull some amount off until we get into the good wire, cut it and put a new eye in it. At some point there comes a time when they need more wire which we mark and deliver to the boat, pulling off all their existing tow wire and then installing it on the bottom of their hoisters (or drums), splicing it into their existing wire. This way the newest wire is always on the bottom and the oldest is on the top (and set into the water first when they set out their trawls or scallop dredges), so you can cut back the oldest as it wears out. Sometimes a customer will be in a hurry or just want to temporarily put new wire on top, but in general we frown on this as down the road it gets to be a big mess trying to figure out what wire is their oldest and needs to be replaced.”

Again, it’s always the basics: Inspect the tow wire and know when it needs to be cut back. Replace running rigging when it shows signs of wear and overuse as well. According to Taber, it’s not uncommon for the wire rope used in running rigging to break, either because it has worn out, was not maintained, hasn’t been replaced in time, or it’s over-loaded when bringing the fish on board. This part of it can be dangerous. Thankfully, when it comes to tow wire, there aren’t many accidents. If they’re out trawling and a tow wire breaks, everything typically ends up on the ocean-side of things. When it comes to their running rigging, wire rope can potentially be more dangerous.

When tow wire breaks, it’s typically hung up on something like a wreck and the wire breaks and that causes them to lose everything (net, trawl doors, etc.). They will mark the location on navigation instruments to record where everything as lost and then try to grapple for it or they may need go back to port to get a grapple and try to get their gear back. But if the tow wire breaks, they’ll usually either make a quick, temporary eye splice or they’ll use a bunch of wire rope clamps.

FROM SEA TO TABLE

The Fulton Fish Market in Manhattan is the largest wholesale seafood market in the U.S. For over a century, seafood products from the entire Atlantic seaboard and other parts of the U.S. and the World have been shipped to Fulton Market for display and sale to retail stores and restaurants throughout the New York City metropolitan area. It’s the largest and oldest of its type, handling millions of pounds of seafood daily, with annual sales exceeding one billion dollars, and is second in size only to Tokyo’s Tsukiji Fish Market.

So, the next time you sit down to dine on a well-prepared seafood dinner, don’t just thank the chef, but remember the fisherman and the wire ropes that hoist in the catch for you to enjoy. And maybe it’s not a bad idea to air high-five King Neptune!

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