July/Aug 2019 Equipment Focus: Stationary Shears

Aug 15, 2019, 18:53 PM
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July/August 2019

By Annemarie Mannion

Manufacturers have improved the energy efficiency, cycle times, and sizing box designs of stationary shears to give scrap recyclers a better return on their investment. they're the top choice for processing thick, bulky scrap no matter how you slice it.

Equipment-Focus-Stationary-ShearsSlicing a rail car or shipping container into pieces that are as little as 18 to 24 inches long has long been the job of the stationary shear, a piece of equipment that is considered a workhorse of the scrap recycling industry. The clanking of ferrous metals and other materials as a magnet or grapple lifts and deposits them into the shear is a signal that the machine will soon be doing its job of compressing and cutting thick, rigid, or bulky materials. Like a hungry beast, it can take in mammoth pieces of steel and other oversized materials and then use its guillotinelike blade to chop them into manageable sizes. It can also densify lighter materials through compression and then cut them into smaller pieces or bundles that a scrapyard can sell to a steel mill or foundry.

While the basic designs of stationary shears have not changed much over the years, incremental improvements have created greater efficiencies that should appeal to scrap processors who get sufficient volumes of the materials these machines are designed to handle. These shears can’t completely replace torchcutting or mobile shear attachments, but they process thick scrap quickly and cost-effectively, transforming it into a product tailored to a steel mill or furnace’s specifications for size and density.

Volume and versatility

An important factor when considering a stationary shear purchase is the volume and grade of material you’re processing, manufacturers and users say. It’s a big decision because shears come with a hefty price tag—in the range of $500,000 to about $5 million.

“If it is financially feasible, buy the stationary shear not for what your business is doing now, but for what you want it to be doing in five to 10 years,” advises Garrett Tracey, chief operating officer and chief commercial officer for Sims Brothers Recycling (Marion, Ohio), which has three scrapyards. The company purchased a shear/baler/logger from a California company about 14 years ago, when it was processing about 1,000 to 1,500 tons of cut grades a month. Now, because of the increased ability to handle large volumes of scrap, it has doubled that amount to more than 3,000 tons a month. Any scrapyard processing more than 1,000 tons a month would find a shear purchase effective, says a sales manager for an Iowa-based manufacturer that sells a brand of shears from Bologna, Italy.

Shandy Vida from Tervita Corp. (Red Deer, Alberta), says the company spent a year comparing products before purchasing a side-compression shear from a Belgian company, which was installed at its Red Deer facility in 2018. Vida says he wanted to improve production rates; he wanted a machine that was easier to operate than a mobile shear (also called a stick shear); and he wanted a machine that would accept a wide variety of material. Stationary shears are “simpler to operate than a stick shear,” he says. “It takes a long time for an operator to become productive running a mobile shear.” The model of side-compression shear his company purchased can process a wide variety of material and facilitates the blending and densification of lighter grades of scrap. “The side squeeze and the hold-down compression capabilities of the machine also support achieving good weights in the rail cars we are loading,” he says.

Operating standards

Though they have some differences, most stationary shears operate along similar principles. A grapple or magnet picks up scrap material and deposits it into a sizing box that presses the material into a compact bundle. A ram pushes the material under a guillotine-style blade that slices the material into specified lengths.

The compression chambers, or sizing boxes, come in two basic designs. The side-compression style squeezes the material from the side and the top and performs best when processing structural scrap, I-beams, truck frames, and other ferrous metal. “If what you’re trapping doesn’t require a lot of manipulation to get it into the box, then the side [compression] shear is quicker,” says the Western region director of sales for a Georgia-based manufacturer.

The tuck-and-fold design has arms on one or both sides of the chamber that support trough-like plates to fold and compress the material. When the chamber is open, the first plate is parallel to the ground and the operator can place scrap in it or in the chamber. The arm lifts and pivots the plate over the scrap, pushing it into the chamber. The second arm also pivots over the chamber, overlapping the first plate to push the scrap from the other side. The process is like folding a letter into thirds. Another variation uses only one moving arm to push the scrap against a rigid chamber wall or floor. The tuck-and-fold-style shear is designed for bulkier items like school buses, farm implements, rail cars, or shipping containers. These boxes typically range from 20 to 40 feet in length.

The Iowa sales manager touts one benefit of a third shear design, the vertical gravity-fed shear: It’s easy to install, making it a popular choice, he says. “The machine arrives on a lowboy trailer, you lower the hydraulic legs on the shear, pull the trailer out from under it, and you are all set,” he says. “After a few setup procedures, you’re ready to start shearing.” In contrast, he says, some other stationary shears take as long as two weeks to assemble. Another benefit of the gravity-fed shear, which uses a ramp to slide material into the machine, is reduced operating costs. This design is best suited to processing less bulky items, like pipe, he says. Steel companies want material of a specific density, and one goal of a shear, particularly one geared toward processing lighter materials, is to get those materials to a density that will fetch a good price. “It’s easy to make density with heavy scrap, but it’s not easy to make it with light scrap,” says the sales manager for a shear manufacturer in Ovada, Italy, outside of Genoa. Some shears, like the one that Sims Brothers uses, have the capability to bale and log scrap as well as shear it.

Shears are rated by their cutting force. The company from Ovada sells models that range from 500 to 2,400 tons of shearing force. “The most common size is the 800-ton guillotine,” the sales manager says. “You can be quite a small company and afford one.” The Western region manager for the Georgia company says its smallest model can process about 17 tons an hour while its largest can process 70 to 80 tons an hour.

While the basic stationary shear designs haven’t changed much during the decades they’ve been in use, manufacturers tout various refinements they say have made them more efficient. Today’s shears are closer to the ground, making them easier to load, says the Ovada company's sales manager. The hydraulics have improved, reducing cycle times, and they can do more with less power, which saves on electricity. “In the last 30 years, hydraulics have changed a lot,” the California company’s general sales manager says. “It used to be that a 1,000-ton shear needed 750 to 800 hp to run. Today, a 1,000-ton shear needs 500 hp.”

Some manufacturers have made changes to the sizing box design. The California company introduced a curved door on the box, for example, which its says allows operators to feed material more quickly. This manufacturer and others envision more improvements in that area. “There’s a lot of high-density crushing going on in the boxes. That’s where the real work takes place,” the general sales manager says. “Manufacturers are looking at reducing the trapping time.”

Installation requirements

Some shear manufacturers customize machines; others do not. “We certainly work to fit our machinery into any space,” says the sales manager from the company in Ovada. “All the elements—the hydraulics, the electrical unit, and heat exchanger—don’t all have to be in the same place.” The California company says it doesn’t customize its shears, but “we sell the machines complete with everything,” the general sales manager says. “We also supply the drawing for the foundation.”

A small shear requires about a half-acre of space to accommodate the machine and have room for piles of scrap and a material handler to feed them into the shear; a larger shear needs about five acres, these sources say. The Western region director of sales for the Georgia company says his company will help processors determine the best placement. “We’ll look at the layout of the yard and what the traffic flow is like and make it easy to load and ship material to the mill,” he says.

Even the smallest stationary shears are heavy, and most require a concrete pad. The designs have evolved, however, to require less additional installation work. “The foundation used to be part of the machine, and you had to build a control house,” says the California general sales manager. “Now the foundation is just a pad the shear is set on. The machine is self-framed, and we have an operator’s cab.”

Increasingly, shears, particularly smaller ones, can be operated remotely, keeping the operator far from the blade and scrap. There is always a risk of scrap falling or shooting out from the blade in an unexpected way, making remote operation one way to improve safety. “If you don’t need an operator around the machine, that’s more safe in that fact alone,” the Ovada company’s sales manager says. Larger shears require an operator in a cab who can see inside the box to ensure nothing will impede scrap loading or compression.

Maintenance matters

Stationary shears will last for decades if companies maintain them according to specifications, these manufacturers and sellers say. One crucial aspect of a shear’s performance is the blades, a costly part worth maintaining. Stationary shears come in a wide range of sizes, thus, so do the blades. Smaller sets start at about $800, while very large sets can be $9,000, with the size, number of blades in a set, bolt hole configuration, alloy composition, and other elements factoring into the price.

Modifications within the blade chemistry and materials have offered increases in strength, durability, and toughness while decreasing brittleness, says the manager for inside sales and marketing for scrap and recycling at a Pennsylvania-based blade manufacturer. Despite these improvements, blades still require maintenance. “You’ve got to make sure the shear is serviced regularly and that the blade is flush with the blade seat,” says the sales manager of a Michigan-based blade manufacturer. This careful alignment often gets overlooked, blade sellers say. “It’s very common for people to think they can just take a blade and slap it in,” says Mike Morrison of the National Association Supply Cooperative (New Philadelphia, Ohio), which sells blades from several manufacturers. “But you need to maintain the seat, clean it, and make sure it’s level.” The Pennsylvania inside sales manager agrees that maintaining proper cutting-edge tolerances is critical “to avoid jamming and ensure proper operation.”

How long a blade will last will depend, in part, on what materials users are cutting and how often and how long they run their shear. Blade sellers caution operators to make sure they are cutting only the types of materials that match the shear’s rating. With those caveats, the vice president and general manager of an Iowa-based blade manufacturer says blades generally last 40 to 80 hours per edge. Too much wear will create excess pressure or side force, which will drag material between the blades and pinch it instead of shearing it, the Pennsylvania inside sales manager says. “Excessive wear also decreases stability in the blade seat on [the] remaining edges,” she adds.

Morrison recommends following the manufacturer’s manual for correct maintenance, blade flipping schedule, and inspection sequence. The bolts, too, need to be torqued to the correct value. Since bolts tend to stretch, become misshapen, or break after many uses, he advises processors to replace the bolts every time they install a new blade set. Loose bolts or stretched threads will create instability and failure in the bolts or blades, the inside sales manager says. It’s also a good idea to have at least one or two spare sets of blades on hand to keep from having to shut down production while you wait for replacements.

Hydraulic systems that lift the knives or tighten the bolts make the shears easier and safer to maintain. “A lot of the adjustments in the shear head, which has the cylinders and knives, can be done externally,” adds the Western region director of sales for the Georgia company. “Many [manufacturers] incorporate mountings or holes to help loosen a blade from its seat during rotation,” the inside sales manager says. “Gibs or guide adjustments may also be part of the design.”

Buying advice

Stationary shear owners and sellers offer several pieces of advice for those in the market for a new shear. “I would say one of the truisms in the scrap industry is that, where practical and affordable, the heavier the better,” Vida says. “Unless you have multiple yards and want to move it around, or [you] are a [demolition] contractor who wants to take it job to job, a heavier machine is going to hold up better against the stresses.”

Sims Brothers’ Tracey recommends buying new instead of used unless you’re very confident that the used shear is in good working order. “There are all kinds of gremlins that you can’t see when you’re inspecting an old machine,” he says.

While manufacturers tout the volumes their shears can process, Vida views those expectations with a grain of salt. Throughput tons “are largely dependent on the type of scrap, so production numbers may not live up to the hype,” he says. “People should chat with other yards that are running the gear to get an accurate sense of output.”

Whatever model you purchase, the goal is saving money by shearing more efficiently, the sales manager from the Ovada company says. “If you can save $1, $2, or $3 per ton, and you multiply that volume over decades, you’re going to save money.”

Annemarie Mannion is a freelance writer based in Willowbrook, Ill.

Improvements in energy efficiency, cycle times, and design make these shears a good bet for cutting large volumes of thick or bulky items.
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