Unique System Keeps Coil Strip on Track in the Die
Ohio Stamping and Machine Inc. Uses Unique Technology From SESCO Products Group to Boost Blanking Capacity
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One way steel fabricating companies save costs is by buying steel coil that is just wide enough to fit their application and part configuration. But this presents its own set of problems, according to James Doyle Vice President and General Manager of Ohio Stamping and Machine, Inc. (OSMI) (Springfield, OH).
OSMI manufactures first-operation blanks and medium to large stampings for the automotive, truck and appliance industries. Both exposed and unexposed blanks are processed to meet critical quality standards demanded by their customers. These first-operation blanks are either cut-to-length or die-cut configured.
To reduce purchased material and scrap costs, OSMI’s customers often specify coils just wide enough to fit their stamping application. However, if the coil doesn’t run through the die perfectly, completely covering the die cavity, the die can be damaged initiating downtime and costly die repair as well as causing scrap parts to be produced.
Doyle added, “One way to assure proper positioning of the steel is by using pilot pins that will locate the steel strip in the die. But this necessitates floor space for a loop or a looping pit so the pilot pins have somewhere to move the steel strip.” OSMI solved these problems for non-piloted compound dies by using a unique coil cradle/straightener/feeder made by the SESCO Products Group (SPG) a Coe Press Equipment Company.
According to Doyle, the SPG equipment cradles the coil, straightens and feeds it all in one process without the need for a slack loop. To keep the steel coil perfectly aligned while being fed into the die, a unique edge-guiding control system is incorporated. It consists of two large hydraulic cylinders to move the entire cradle/straightener/feeder side-to-side.
The SPG cradle/straightener/feeder floats over the floor on heavy-duty machine rollers while the hydraulic cylinders, one in the front and one in the back, move it for proper coil alignment, ensuring the die cavity is completely covered. Doyle said, “to do this we developed an optical coil strip edge- sensing system on the press that communicates with the hydraulic cylinders to move the cradle/straightener/feeder as needed. The coil strip has to move pretty quickly, and you have to move the entire cradle / straightener / feeder. That is a lot of mass to move. This application has been very successful for non-piloted compound dies. It has cut down our die miss-hits, scrap and scrap handling.”
Doyle said that SPG’s cradle/straightener/feeder runs up to 60 feet per minute and feeds a 500-ton Clearing straight-side press. High-strength alloyed steel is primarily processed. “This kind of steel is tough to deal with, because it has a tremendous amount of memory in the coil. If you loose control of the coil, it will ‘clock spring’ and could be dangerous. We are running close to 0.200” thick material. The equipment is ideal for numerous applications with heavier gage steel because it maintains coil control, it is very compact, and the heavy-gage steel feeds straight into the die. Lighter gage steel runs better with a loop.”
This system can handle a 50,000-lb coil with widths ranging from 6” to 60” and material thickness from .060” to .375”.
Heavy-Capacity Unwinder Boosts Blanking Line Efficiency
One of OSMI’s newest lines has a massive coil capacity that uses another unique SPG design to efficiently process blanks. This line has a single-ended traversing unwinder with 84” maximum coil width and 70,000 lb maximum coil capacity. The unwinder is designed with a unique traversing outboard support for handling this extreme coil weight. It has a stationary hydraulic coil elevator that positions the coil vertically for pickup by the traversing coil unwinder. It also has a peeler/threader station, straightener, looping pit with a threading table and servo feeder.
What’s unique about this line is the capacity to process a wide range of material widths and thickness. It can handle a maximum coil width of up to 84” by 0.187”thick and a minimum width of 12”. Strip thickness ranges from .025” to .250” at a 42” strip width. OSMI runs either 1018 cold-rolled galvanized coated steel, or hot-roll uncoated through a 1200 ton Blow straight-side press.
Doyle said that they purchased this 70,000-lb coil line capacity because “market opportunities drove us there. We had a quest for efficiency, and being competitive. This line is a backup to three existing lines; a conventional SPG line with an 800-ton press, a 1000-ton press line that didn’t have any production backup, and also a large-bed 300-ton press line that produces exposed blanks for automotive customers. It really filled a need because of the expansion of the company.”
“I have been here eight years, and we have been adding on the whole time. Our operation just keeps building and growing. We now almost fully occupy our 13.5 acres. Our latest expansion was to our shipping and receiving building that doubled its size tomake more room in our main plant for the coils and ancillary equipment needs to support our ten press lines.
Doyle added that the new SPG line provides the company with the capability for long feed lengths, exposed and unexposed product, and larger coils. The large coils require less down time and fewer minutes in a shift dedicated to coil change. SPG was chosen for the large conventional coil processing equipment because, “OSMI personnel liked working with them on our prior projects. We achieve a very high level of production uptime hours every week, so we need rugged, robust equipment with excellent service support. We are in a Just-In-Time world and there is no place to hide if you run into trouble. And when we need help, SPG is there. We like that SPG listens to our need, proposes solutions and we collectively decide on what needs to be done to solve a problem.”
“SPG is good to work with from a technical standpoint, and are flexible from an engineering standpoint. They proved with the first purchase their service was good, and their machines held up under the duty cycles we put them through. We have given them feedback on improvements to existing equipment or new designs and they listen to what the problems are. Then they come up with a solution and sometimes we incorporate it into the old equipment and certainly we incorporate it into the newer designs.”
Doyle added, “Three of our lines use SPG equipment. We just finished a year where we processed 150,000 tons on 10 press lines. That is a lot of steel. We shipped 150 fully loaded trucks out of here a week. OSMI is the largest generator of scrap clips in Southwest Ohio. We generated over 20,000 tons of scrap clips last year. We are a high-volume 24 hour a day operation with an inventory of 20,000,000 lbs. of steel and production of 30 million blanks and stampings per year. Our average press operating uptime per week is over 80 hours for ten presses with ten to fifteen jobs per press running in each press every seven or eight days. We are also an ISO 9002 and QS 9000 compliant registered firm.”
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