A Blanking Press Odyssey
Sesco Coil Handling/Feeding System Speeds Setup Time While Reducing Scrap for Minivan Part Stamper
Getting steel into and out of stamping presses the fastest and most efficient
way possible is imperative for KTH Leesburg Products LLC, Leesburg, AL
(KLP). Finding the right stamping equipment to do it efficiently and quickly
is essential to increased production and now it’s twice as important.
So much that KLP is adding stamping capacity to boost production, and
doubling their overall 173,000 sq. ft. of plant space to nearly 345,000
sq. ft.
KLP, a Japanese transplant stamping and welding company that serves Honda Motors, is a captive stamping and welding facility (parent company KTH Parts Industries, St. Paris OH) that primarily produces components for Honda’s Odyssey Minivan produced in Alabama and also supplies parts for Honda’s Pilot and Element vehicles. KLP also has sister facilities in St. Paris and Kalida, OH, and Shelburne, Ontario Canada.
At the Leesburg facility they have two AIDA presses, a 2500-ton transfer press and a 600-ton blanking press, with a third stamping line under construction that will use an AIDA 1500-ton transfer press. Typical blanked parts that the company produces range from 0.020” to 0.125” in thickness, from 8” to 72” in width and from 6” to 96” in length. Once the parts are stamped, welding is primarily done automatically using over 100 Fanuc robots.
“Our
present capacity is 670 stamped and welded units daily (IE: wheel house
and damper housing assemblies, side and floor frame assemblies, etc.)
using two shifts, which is also Honda Manufacturing of Alabama’s
capacity for these parts,” says Stamping Department Coordinator Jim
Cecil. “Everything that we stamp and weld here is considered a frame
or an undercarriage part.”
With demand increasing for Honda's minivan, KLP opened the Leesburg plant in September, 2001. Their equipment selection was important to keep up with demand. For their coil handling/feeding equipment mated to a 600-ton AIDA blanking press, they selected Sesco Products Group equipment (Sterling Heights, MI) for blanking galvineal hot-and cold-rolled steel operations.
Describing The Sesco System
The specifications for the Sesco coil handling/feeding equipment included some unique features to help KLP speed production and reduce scrap. The high speed blanking line consists of a traversing pull-off type centering reel with an A.C. backtension and threading drive; a hydraulic traveling coil car; a coil peeler, hold down, dekinker, and threading-assist assembly; a nine-roll fully driven precision straightener; a stock-threading table and loop control system; an electronic servo roll feed, and a coil-end electronic servo microfeeder.
KLP's 600 ton AIDA blanking press produces different shaped blanks that are then used on the larger transfer press. It also makes several different types of progressive die parts. The coil car is used to pre-stage a coil and then load a coil on the uncoiler. An automatic coil centering feature by job recipe is provided to assure proper coil positioning. The dekinker unit is used to provide an upward bend on the leading edge of the coil so it can be properly threaded through the line.
A
hydraulic crop shear station is located prior to the precision straightener.
This station is used to cut off any damaged material from the coil OD
and trim the leading edge of the coil prior to threading. During the threading
process the A.C. backtension drive maintains proper tension on the coil
to prevent any clockspring action. If the threading process is delayed
a holding brake is automatically applied. The Sesco nine-roll precision
straightener is provided with many features to assure strip flatness and
long term integrity. The 6.0" diameter entrance and exit pinch rolls
are provided with a single-row of center backups for deflection reduction
and effective pull-off operations. The close centered 3.5" diameter
straightener rolls are provided with a double-row of backups. All pinch
rolls and strightener rolls are positively driven for efficient transfer
of torque from the 75 HP A.C. variable speed drive system.
Following the straightener, the coil stock is directed into a looping pit that is designed for proper material storage so the line can operate at speeds up to 230 FPM. Full radiused catenary sections are provided at each end of the looping pit to support the material and prevent coil set from being re-induced into the strip. The high speed servo feed unit on this line is designed with 7.0" diameter feed rolls that are backed up to prevent deflection and prevent marking of the coil strip. The servo feed is driven by a high performance AC servo motor and the drivetrain consists of precision gearing running in an oil-filled sealed bath.
On The Microfeeder
An
important feature of the Sesco blanking line is the coil-end electronic
servo microfeeder. It's motor driven and adjustable to telescope through
the press column opening and into the bed area. A total travel of 42"
is provided to allow feeding of the coil tail strip as close to the die
as possible. The microfeeder rolls are manually operated by a jog button
to locate the coil stock in the die. This unique equipment has helped
KLP reduce coil scrap and improve efficiency. Instead of wasting from
10' to 20' of expensive Galvineal stock during changeover, waste is greatly
minimized to sometimes only 24".
Cecil estimates that the microfeeder saves them thousands of dollars in reduced scrap annually. "If we were running three shifts or more it might be higher." Changeover time is also reduced with the microfeeder. Cecil adds, "while the last short bit of coil strip is being fed through the microfeeder, we have the capability to go to the uncoiler and load our next job. The microfeeder gives us time savings and definitely cost savings. It cuts our coil change time by 50%. I would think that anyone that is feeding progressive dies, especially with small feed parts, should have a microfeeder, even if it is just for the scrap savings on the strip."
Sesco's
coil hold down, threading assist assembly, dekinker, hydraulic crop shear,
straightener, threading table, and servo feed prepare the coil stock for
feeding into the press. Cecil says they use the threading assist and dekinker
equipment because of the different steels that they have. "We have
steel that is 0.125" thick that is tough to thread through the equipment
and it needs to be dekinked. We have such a wide variance of product that
we run through, and we do use the dekinker on several parts, so we need
it."
Instead of using a traditional five-roll or seven-roll straightner, KLP uses a Sesco fully-driven precision nine-roll straightener for greater flatness throughout of their wide range of materials. "We don't want curled edges or anything on a stack of parts, because it makes it more difficult in the transfer press to destack and feed the parts," he adds.
Set-up;
Operation Enhanced
To keep the press uptime high, fast setup is essential. The Sesco equipment has an Automatic Set-up Through Data Entry feature that allows fast setup. The operators don't have to hand crank wheels to set the material widths, feed lengths, pilot release windows, feed angles, straightening roll depth settings, coil centering position, passline height, or micro-feeder positioning. All functions are motorized and setup done automatically as data is downloaded by job recipe. "If we had to check and visually crank coil guides, we couldn't get 13,000 stampings in 8 hours," Cecil remarks. "If we had to do these things by hand, our setup times would at least double. And then you have an accuracy issue. If somebody thought they saw the stock touch a roll and it didn't, you might end up with a feed problem halfway through the coil."
A one time-saving feature of the plant is the in-floor bolsters for early movement of parts bins. The plant also uses quick die change equipment for the AIDA presses. KLP has gone to great lengths to make sure that they are running as efficiently as possible by implementing these two time-savers.
Cecil says that his operators like the Sesco system's ease of operation. The line functions are PLC controlled and three (3) color-coded Proface touchscreens are used as the primary operator interfaces. One operator said that if the screens are all in a green mode you know that you can proceed with the stamping process. If the screens have yellow or a blinking light or something other than all green, the line has a problem.
Two
associates work on the Sesco/AIDA blanking line each shift. "Our
goal per shift is 13,000 stampings off the blanking line," says Cecil.
"As an average, we get that in eight hours. Our first shift can work
9½ hours and the second shift can layover 10 hours. Normally that
is not needed, we supply our 2500-ton transfer with 8 hours worth of work.
It's hard to put a time for die and product changes on that line, but
it's probably done at least seven times per shift.
"Most of our blank dies run close to 60 or 65 strokes per minute, about 3,600 shots in an hour. That's a fair average, our progressive dies are going to run slower," remarks Cecil.
Parts produced by KLP are welded then go through eight different quality inspections. Stamped parts typically get staged onto a Kanban-type cart and then wheeled to the appropriate weld-line area. They employ over a hundred welding robots in all. They have a destruct booth that helps them track quality control by destroying the welds. KLP also uses impact testers to try and destroy the welds as required by their quality control systems.
Cecil says, "The Alabama plant here has done extremely well because of our quality. And quality is the way Honda does business."
Success Stories
Sesco Coil Handling/Feeding System Speeds Setup Time While Reducing Scrap for Minivan Part Stamper
