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Mechanical Presses

Perfect parts

By Lynn Stanley

Mechanical press offers a simple solution for complex fabrication

July/August 2012 - The cold-formed steel industry’s competitive environment is driving today’s manufacturers to streamline operations and adopt technologies to increase efficiency and add value to end products. California Expanded Metal Products, known as Cemco, took these business practices a step further when it developed an innovative floor joist system called Sure-Span.

The system required new roll-forming, embossing and flaring technologies that could meet evolving consumer demands, strict industry standards and Cemco’s criteria for quality and affordability. The company’s manufacturing and engineering teams were tasked with finding a press that could anchor the line and fabricate complex parts.

Based in City of Industry, Calif., Cemco has four production plants and is one of the largest manufacturers of steel framing and metal lath systems in the United States.

“In 2001, one of our principal competitors was working on developing a system similar to our concept,” says Georgi Hall, director of engineering at Cemco and the inventor of Sure-Span. Aware of the competition, Cemco decided it needed a product that would give it an edge. Hall completed development of the light-gauge steel floor joist system in 2002.

Sure-Span’s patented system can support both commercial and residential construction projects. Unlike conventional floor joists, Sure-Span features large trapezoidal-shaped punch-outs that give plumbing, HVAC and electrical contractors built-in access for a variety of services without sacrificing the structural integrity and sturdiness of long floor spans.

“Traditional over-sized or atypically large punch-outs compromise the floor joist’s overall capacity and structural integrity,” Hall says. “Our system eliminates this problem with specially designed flares and embossment. These features counter reduction of sectional strength due to holes. As a result, Sure-Span exhibits equal or greater strength capacity when compared to floor joists with no punch-outs.” Prototype testing verified Hall’s findings.

To produce the floor joists commercially, Cemco needed the right press. The manufacturer submitted drawings to several press manufacturers but found the recommended machines complicated and too expensive.

The right press

“Though an experienced roll-forming company, this type of flaring and embossing was new to us,” says Hall. “We needed press technology that we could understand and easily train our personnel on. We didn’t need machines with a lot of bells and whistles. We wanted something simple to maintain that could accommodate our die designs and our budget.”

Sutherland Presses, Malibu, Calif., offered a practical solution. “They evaluated our requirements and provided us with an affordable turnkey manufacturing line,” says Hall. “The floor joist system represented a carefully developed and tested new concept. Sutherland gave us a simple solution capable of performing a complex job.” A global press supplier, Sutherland provides built-to-order mechanical, hydraulic and forging presses as well as feeders and automation options.

In addition to punching, embossing and flaring, Cemco operators needed to cut joists to custom lengths within strict tolerances all on the same manufacturing line.

“We came up with the idea of bolting an air-over-hydraulic shear onto the second press,” says Hall. “Sutherland helped us integrate the shear into the system. Without their help, we would have been required to purchase an additional 100-ton press, preventing us from achieving the small footprint we needed for the line’s placement. Sutherland’s engineers took the equipment we made and incorporated it into a system of servo controls, which allowed our operators to run the entire line automatically.”

Hall also worked with Sutherland to design the press windows to ensure they were large enough to accommodate a 24-in.-wide piece of flat stock.

With more than 65 years of experience, Sutherland knows its machines and the unique requirements of North American customers like Cemco. “We specify each component that goes into a press,” says Mark Sutherland, president of Sutherland Presses. “The ability to quickly supply off-the-shelf components is a key part of our service support.”

For Sutherland, however, it’s the press builder’s philosophy about the vender/customer relationship that sets the manufacturer apart.

“It’s a joint effort—a partnership,” he says. “Cemco was clear about their challenges and goals. By taking the time to listen and understand their process, our team was able to both optimize and simplify the line to meet their needs. We’ve seen all types of materials—sheet, coil and plate steel—being produced in some form. That gives us a data pool we also can draw from to help customers with unique requirements.”

In 2002, Sutherland installed two SC1 176-ton mechanical straightside presses with compact servo feeds (HR 0660 24 in. by 10,000 lbs. K reel). The floor joists are produced from hot-dipped galvanized, mill-certified prime steel 18 gauge to 12 gauge in widths of 71⁄4 in. to 14 in. Coating thicknesses can be G-60 or G-90. Part lengths range from 8 ft. up to 60 ft.

The coil line, two presses and shear are operated with a single control system. Strip coils are fed to the first press, which performs punch-outs every 4 ft. The second press initiates flaring and embossing. The line can produce punch-outs for things like water lines, copper piping and air conditioning. Openings also can be punched in various patterns.

“Sutherland basically broke our process down into seven commands for the servo feed,” says Hall. “Our operator plugs in parameters like part length, feet per minute and how many joists the part run requires.” The feeder recognizes the reference points for the punch outs and will run automatically. Called gag feeding, the servo can be programmed to accommodate irregular or varied feed lengths within a part run.

Flexibility

In addition to floor joists with large, flared punch-outs, Hall developed a pre-indexed, pre-spaced Sure-Span rim track that provides easy installation while meeting joist spacing, engineering and building-code requirements. During the first two years of production for these framing components, Hall noticed a lot of scrap generated from the trapezoidal punch-outs. Hall got the idea to take the scrap and turn it into a clip that fastens to the rim track with screws. The floor joist attaches to the pre-installed clip.

“The clip was a part we originally outsourced,” he says. “Since we use a modular die system and the press bed size was large enough, we were able to accommodate a new die to form the clips. Trapezoidal coupons are manually fed into the press and cropped into rectangular pieces before being punched with specified features and holes. The third die station forms a bend and finishes the part. We’re always looking for new ways we can use the press.”

After a decade of operation, Hall says Cemco has experienced no problems with its dies or the presses. The manufacturer produces 120 linear feet per minute, which adds up to 36,000 linear feet per sheet. “Reliability is important to us,” says Hall. “When you introduce new products, you have to be able to meet market demand, rigorous industry tolerances and customer lead times.”

Each press weighs 30,000 lbs. to 40,000 lbs. more than standard presses from other builders. “This sturdy construction gives our presses the rigidity and strength to accurately perform processes like drawing and embossing,” says Sutherland. “It also supports lower deflection and allows multiple operations to occur during one cycle of the press. Minimal total stack up clearance in the press’s connection points allows for high-accuracy bottom dead center work. We use an enclosed profile to contain moving parts within the structure of the press. This design feature helps create a safe working environment for operators and contributes to less maintenance.”

While Cemco doesn’t have much downtime on the presses because of production demands, the manufacturer does have some free shifts and is looking to fabricate other types of clips on the line.

“Sutherland gave us a dependable system with controls we could program any way we wanted,” says Hall. “The line is customizable and has the flexibility to support additional products we develop or handle runs for parts we currently outsource but may want to bring in-house.” FFJ

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Sources

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Company Profiles

AIR FILTRATION

HYDRAULIC PRESSES

NESTING SOFTWARE

SERVICE CENTERS

Camfil APC - Equipment Beckwood Press Co. Metamation Inc. Admiral Steel
Camfil APC - Replacement Filters Triform

PLASMA TECHNOLOGY

Alliance Steel
Donaldson Company Inc.

LASER TECHNOLOGY

Messer Cutting Systems Inc.

SOFTWARE

BENDING/FOLDING

AMADA AMERICA, INC.

PLATE

Enmark Systems Inc.
MetalForming Inc. Mazak Optonics Corp. Peddinghaus Lantek Systems Inc.
RAS Systems LLC MC Machinery Systems Inc.

PLATE & ANGLE ROLLS

SigmaTEK Systems LLC

BEVELING

Murata Machinery, USA, Inc. Davi Inc. Striker Systems
Steelmax Tools LLC TRUMPF Inc.

PRESS BRAKE TOOLING

STAMPING/PRESSES

COIL PROCESSING

LINEAR POSITION SENSORS

Mate Precision Tooling AIDA-America Corp.
Bradbury Group MTS Sensors Rolleri USA

STEEL

Burghardt + Schmidt Group

MATERIAL HANDLING

PRESS BRAKES

Alliance Steel
Butech Bliss Fehr Warehouse Solutions Inc. AMADA AMERICA, INC.

TUBE & PIPE

Red Bud Industries UFP Industrial Automec Inc. BLM Group
Tishken

MEASUREMENT & QUALITY CONTROL

MC Machinery Systems Inc. Prudential Stainless & Alloys

CONVEYOR SYSTEMS

Advanced Gauging Technologies SafanDarley

WATERJET

Mayfran International

METAL FABRICATION MACHINERY

PUNCHING

Barton International

DEBURRING/FINISHING

Cincinnati Inc. Hougen Manufacturing Flow International Corporation
ATI Industrial Automation LVD Strippit

SAWING

Jet Edge Waterjet Systems
Lissmac Corp. Scotchman Industries Inc. Behringer Saws Inc.

WELDING

Osborn Trilogy Machinery Inc. DoALL Sawing American Weldquip
SuperMax Tools

METAL FORMING

HE&M Saw Strong Hand Tools
Timesavers FAGOR Arrasate USA Inc. Savage Saws T. J. Snow Company

 

MetalForming Inc.

 

 

 

MICROFINISHING TOOLS

 

 

 

Titan Tool Supply Inc.

 

 


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