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 Since
it installed touch-screen personal- computer-based controllers
on its presses, in conjunction with PLCs for monitoring
and controlling ancillary press functions, the Lear Corp.
stamping plant in Roscommon, MI, boasts almost Herculean
improvements in process efficiency and productivity. The
plant, with 12 presses that help it ship 1-million parts
per week, improved its pressroom output by 65 percent over
a nine-month period and brought diechange times down from
an average of two-plus hours to 44 minutes, all while reducing
its standard run quantities from an average of 5.1 weeks
down to less than five days.Plant engineering manager Tim Bossingham, explains the productivity push. “ With networked PCs at every press for live production-data gathering, management now can take snapshots of the pressroom, perform downtime analyses and view die-set reports. Before, everyone had an opinion of what might be restricting throughput and delaying production.Now we speak with data, and take corrective actions before small problems become big problems. If you don’t know what’s happening out on the floor, you don’t know what corrective action to take.” So Much to Learn, So Little Time When Lear purchased the Roscommon stamping plant from ITT in 1997, the eight-press facility billed $19 million in sales. Today, it runs 12 presses and will bill $44 million in 2003, supplying three Lear seat track assembly plants with structural-assembly stampings and assemblies for automotive seats, such as seat-frame components, torsion bars, seat-recliner mechanisms and power seat-track assemblies. |
As
Lear consolidated operations in recent years, it asked the Roscommon
facility to step up and find ways to take on more work. In 2001,
to get a handle on its pressroom activities and quantify nonproductive
shop time such as unscheduled press downtime and prolonged and
repetitive die-set hiccups, Lear invested in new press-automation
controllers (Maximizer units from Toledo Integrated Systems, Holland,
OH) for three of its 12 presses.
The Roscommon team’s immediate challenge in June 2001: Get
those controllers online to gather and analyze data, and connect
the nine remaining presses. By that August, six presses were connected
and sending data upstream to management. By December 2002, all
the managers could track activity at all 12 presses—six
400-ton models, a pair of 250-ton presses, and a 200-, 300-, 500-
and 800-ton press.
Maximizer press controls offer basic functions such as tonnage
monitoring, die protection, die and job storage, counters for
parts, batches, die strokes and bins, as well as options including
display of shut-height adjustment, a servo-feed interface, tonnage-signature
analysis and preventive-maintenance logs.Add Toledo’s MaxNet
customizable networking software, which allows users to interface
presses via a LAN, as has Lear, and management gains compiled
databases it can use to create a variety of reports. These include
downtime reports, production analyses, shift summaries and individual
operator job output.
The Roscommon plant purchased nine MaxNet licenses, so that several
people—the operations manager,materials manager, engineering
manager, plant manager, tooling engineer and maintenance engineer—can
access the data and run reports simultaneously. They can view
live data from every press, view the counters, see the reasons
why a press might be down and which job is loaded, and check the
run schedule. They also can collect the data and, perhaps most
usable to them so far, compile downtime reports that let them
see at a glance the most common reasons for downtime. Operators
enter
this information right at their press control, using custom menus.
Downtime Reporting: Lessons Learned
Every press control includes a card swipe and all employees have
their own ID cards that they must swipe every time they perform
work on a press.
“ We maintain five levels of access— Level 1 operator,
Level 2 die setter, Level 3 toolroom, Level 4 maintenance and
Level 5 master,” says Bossingham.“ When anyone performs
work on a press, whether it be die tweaking, shutheight adjustment,
etc., we know who did the work, how long it took and why the work
was done. Then we extract that data from MaxNet to create downtime
reports.”
The Roscommon team attributes the downtime-reporting function
of MaxNet as the biggest contributor to productivity and efficiency
improvements. The downtime reports, which can be run by shift,
by individual press or by operator, let the team quickly identify
the leading causes of press downtime and address them.
That’s exactly what has been done. The team had, for example,
found that operators continuously made adjustments to the pneumatic
shaker conveyors, so they bought new mechanical shakers, and downtime
relative to shakers decreased by 50 percent. Also, presses stayed
down while operators waited for hi-lo drivers to deliver material
and The plant eliminated press downtime caused by bin changes
by installing a part-chute diverter that allows the operator to
divert parts to a second bin when the first one fills, without
having to stop the press. Also, using shop-floor data, it discovered
that a leading cause of press downtime was operators waiting for
hi-lo drivers to deliver material and change part bins. So, Lear
purchased 24 stand-behind pallet jacks, one shown here, to replace
five hi-los on the floor and allow operators to change their own
part bins.
change part bins. So the plant purchased stand-behind pallet jacks
to replace several hi-los on the floor.Now, the remaining hi-los
come by and drop a few bins at each press and take parts away,
and the operators use the pallet jacks to change their own part
bins so presses can continue to run.
Another downtime issue, quickly addressed once identified, was
simply too few operators. The Roscommon team discovered that presses
sat idle because operators were pulled away to perform ancillary
functions or help out at other presses. Two years ago, Lear had
only 10 operators to run the 12 presses, the theory being that
at any one time during a shift, some presses were undergoing die
setups and not running production anyway. MaxNet data showed management
that it needed more operators, as presses ready to run had no
operators to push the button. Management went to Human Resources
for help and immediately added several press operators to the
ranks.
Die Sets, First-Time Die Yields and Action Plans
Lear-Roscommon stocks 420 active dies, mostly progressive, with
an average of 40 under service at any given time.As the shop’s
standard run quantities have continued to shrink, a total-productive-
maintenance scheme has been critical in avoiding emergency die
repairs, and ensuring efficient last-part-off to first-part-off
die changes.
The Roscommon team can run a Die Setter Production Report that
gives total setup time for the day, by shift or even by the die
setter. Managers then can see which dies take longest to set and
take corrective actions to make sure they focus improvement efforts
where they will get the biggest return.
Also gathered from that report are data showing first-piece die
yield, displaying the number of good parts run on a newly set
die before that die needed attention from the press operator or
a toolmaker. Once they tell MaxNet what minimum number of parts
is satisfactory as a good first-piece die yield, the program identifies
which dies are causing the most problems.
Bossingham showed us a recent Die Setter Production Report that
covered one week of work on all presses. Over that time, the shop
set 277 dies, 230 of which met the requirement as a good or acceptable
first-piece yield.“
Once we study the report,” says Bossingham,“we can
write action plans to improve the performance of the dies that
continually fail first piece die yield. The report can be exported
into an Excel file and sorted in any number of ways to find the
repeat offenders.Maybe one die constantly breaks punches, or one
might need more lift in one area of the die, etc.My action plan
might then require the tooling engineer to fix a specific problem.
That’s the beauty of speaking with data—we quickly
can focus in on a problem and fix it before it causes too much
trouble.”
As an example, Bossingham describes one of its newer dies, used
to form Dodge Ram seat tracks. Initially, the plant experienced
trouble running the cam-driven form station on the lower track
die, where tolerances are very tight. Looking at the first-piece
yield data from the Die Setter Production Report,management learned
that toolmakers were constantly tweaking the form station and
the press operator had to adjust shut height to attain 90-deg.
angles and square walls.“
We eventually redesigned the die based on the reports,”
says Bossingham,“ and also discovered that we had insufficient
pneumatic lines serving the pneumatic cylinders used to drive
the cam forms.We had leaks, insufficient air flow and sticking.
Toolmakers were spending far too much time tweaking that die and
not addressing the real problems.”
The Bottom Line: Earned Hours or Productivity
Ultimately, the true measure of reduced downtime and improved
throughput is productivity. Lear measures pressroom productivity
with a yardstick it calls earned hours—if, for example,
it rates a job at 1600 parts/hr., and successfully produces 1600
parts/ hr., it credits that job for one earned hour. Productivity,
therefore, is the ratio of earned hours to hours worked.
A
couple of years ago, the Roscommon plant was in trouble regarding
its Using the Die Setter Production Report that shows, among other
things, firstpiece die yield or the number of good parts run on
a newly set die before that die needed attention, Lear management
addressed quality issues with the die used to form the seat track
shown here. Based on the reports, it redesigned the die. earned
hours. It had numerous pastdues and its corporate materials director
made plenty of phone calls to check on orders. Using MaxNet data,
managers can view earned hours in snapshots throughout the day—while
each press runs, every hour the press control takes a snapshot
of the throughput on that press. MaxNet then compares the data
to a standard for that shift and job, allowing them to compute
their earned hours hourly. Previously, when the corporate materials
director would call with questions about particular orders, the
team would make him wait until the end of a shift to measure what
was produced and try to figure when the job might complete. Now
they can tell him what he needs to know when he calls.
Tracking earned hours consistently throughout the day lets Lear
managers address productivity-limiting issues early in a shift,
so the issues don’t linger. When they recognize a shortage
of earned hours in the midst of a job, managers might, if a tool
is down, send a tooling engineer immediately to the press to troubleshoot.
Or, they might notice that earned hours are down because the press
isn’t running at the proper stroke rate—maybe an operator
slowed the press down due to worries about misfeeds. In that case,
management would dispatch a team as soon as possible to find out
why the press had been slowed, and what needed to be done to get
it back up to speed. In the end, the plant has enjoyed a 65-percent
jump in pressroom productivity.
“ We’ve made some big, big changes around here in
the last year or two,” concludes Bossingham, “and
a lot of it revolves around the data we now have at our fingertips
.” MF Sample screens from the Maximizer press-automation
controls show a System Monitor screen (top) used to track throughput
and give the operator and viewers monitoring production remotely
on MaxNet a look at the parts, tub and batch counters; and the
Operator Downtime Selection screen (bottom) that prompts the operator
to enter a downtime code every time the press stops—downtime
codes include no operator available, waiting for steel, waiting
for a bin change and quality checks.
www. m e t a l f o r m i n g m a g a z i n e . c o m NOVEMBER
2003 39
Removing scrap efficiently during stamping An overview of options
By Paul Tamlin
Since the early days of metal stamping, removing scrap from stamping dies and presses has caused many headaches. Because scrap is not the primary product companies produce, it receives less attention than the finished products coming off the press. However, if scrap is not removed from the press in an efficient manner, the cost per part produced increases.
How a company chooses to implement new processes can play a large role in where it will be in years to come. If a stamper wants to expand the business, how scrap is handled can impact the bottom line and product efficiency. Prospective customers would rather see operators checking parts than standing in front of a press watching it go up and down and clearing scrap manually.
Regardless which scrap removal system best suits a stamper's operation, process, people, and budget are the primary factors to consider for each option. Following is an overview of some of those options.
Air-blast Systems
Years ago it was common practise to move slugs from under dies by clamping an air line onto the bolster and blasting it with air. This removed not only the slug but also any oil that was on the bolster, creating an airborne mist throughout the plant.
If air will be used, it should be controlled with air solenoids that are programmed with the press controls, which can coordinate short bursts as needed. The noise level can become high if several units are in operation at the same time.
Air Shakers and Transporters
Air shakers and transporters have a bore within them like an air cylinder. They have either a bumper or valving that changes their motion enough to cause anything on the trays in which they are drivng to go one way. They simulate the "tablecloth effect" by pulling the tray from under the material and causing it to move forward.
This type of scrap removal requires frequent filling of the lubricator, sometimes daily. The equipment is portable, fits in small areas, and is suitable for use with smaller presses.
The weight of the trays-both total weight and weight distribution-determines what size press these units can be used on. The total weight of trays driven by an air shaker cannot exceed the manufacturer's rated weight capacity. Also, the trays must be balanced to prevent side loading on the guiding mechanism of the shaker unit.
Scrap is removed under the die and a tray moves it to a bin by a 2 axis system.
For installations that have too much tray weight,
multiple shaker units can be installed to stay within the manufacturer's
capacity limits.
Different tray sizes must be attached for different-sized jobs.
A rigidized tray material can be used to overcome the effects
of using a heavy oil lubricant. The material looks like pebbled
steel with a texture that has peaks and valleys. The scrap slides
on the peaks while the oil flows in the valleys.
The more care and time given to the installation of the system,
such as extra quiding for trays, the better the result. Shakers
that are permanently mounted with proper tray support or balancing
can be durable. Reliablility varies depending on the application,
such as when systems are removed and installed for die changes.
Belt Converyors
Most belt conveyors are designed to handle parts that are uniform
in shape and large enough to avoid getting caught under the
edge of the belt. These conveyors are well-suited for removing
finished parts from the ends of the press to part boxes or packers.
A belt conveyor removes finished parts from the ends of the press to part boxes or packers.
They should be set up with two boxes for running
a single part so that the press does not need to shut down while
waiting for a lift truck to bring an empty container.
Some manufacturers specifically design small conveyors for scrap
removal under dies. They feature a low profile for more clearance
of scrap, side guides to reduce the amount of scrap that gets
under the belt, and quick-belt-change systems.
The shape, size, and sharpness of the scrap must be considered
when selecting a conveyor type and belt. Conveyors should be stored
away from traffic areas when not in use to reduce the risk of
damage.
Belt conveyors can be driven by air power, electricity, or hydraulic
power. Two people usually can move them from one press to another.
Although fixed in size, these conveyors can be adapted for width
with the addition of deflectors. They can be used to remove material
on an incline, if required; the angle of incline can be increased
with the addition of cleats to the surface of the belt.
Sometimes slugs do not fall off a conveyor belt but instead go
around the pulley, causing them to carry over onto the bottom
side of the belt. Smaller pulleys are less likely to carry over
scrap because of the smaller roller diameter and the decreased
traction force to keep the belt moving. The use of heavy stamping
lubricant will increase the amount of carryover on the belt.
Belt replacement usually is required if the belt is torn or ripped.
Steel Hinge Belt Conveyors
Hinge belt conveyors are rugged conveyors that use steel plates
with built-in hinges between the plates.
Shuffle Drive on a 600 ton press with a 12' bed dropping onto a hinge belt system.
They use a positive drive system with a roller chain,
which is part of the belt system. The pin in the roller chain
is the same pin that goes through the hinge. Side wings typically
protect the chain, which keeps the scrap from getting into the
chain rollers.
The conveyor should be wide enough to keep the scrap away form
the side wings, because this is where damage will occur in the
transitions from flat to inclined sections. These are well-suited
for elevating material into hoppers such as trailer or lugger
bins above floor level, because large cleats are welded to the
belt. They also are commonly used in pit applications and are
stationary because of their weight.
The most common hinge belt pitches (the distance from center of
one hinge to the next) are 1.5, 2.5, 4, 6, 9, and 12 in., with
the largest pitches availible in widths up to 144in.
Vibratory Trough Conveyors
Vibratory trough conveyors typically are used for horizontal movement
of material. They move material by causing it to make small jumps
along the tray. An eccentric, which moves the tray upward in an
angular motion, causes the product to be thrown slightly ahead,
and this movement can be repeated several hundred times per minute.
The trays are supported by various means, such as rubber elements
or fiberglass leaf springs. The advantage with the tray is that
there is no belt to get damaged. These can be used under presses
or floor-mounted for moving material horizontally and then dumping
it into an incline conveyor for filling hoppers. Since tray supports
are on an angle it is possible that they could be overloaded and
stall.
Because these conveyors use trays, no material carries over, keeping
the pit or floor clean. The vibration of the material does create
some noise.
Shuffle Drive Tray Systems and Trough
Conveyors
These heavy-duty patented Shuffle Drive systems can be press mounted
for scrap removal from under the dies or floor mounted for pit
applications. The Shuffle Drive creates a motion in the tray similar
to the tablecloth effect to move scrap in the desired direction.
2 axis system, with a tray in the bolster and cross feed trays between the feeder and press.
They typically are used on presses with capacities
higher than 150 tons.
These motor-driven gearboxes move the tray back and forth at about
70 strokes per minute (SPM). Only one is required per press, and
it is usually mounted on the column, transmitting its motion across
the press with a pivoting cross shaft. These systems are designed
to become part of the press and usually are not portable. Their
operation is quiet.
During die changes, the trays are lifted up from the cross shaft;
when the next die is placed on the bolster, the appropriate trays
slide in between the parallels and sit on the cross shaft.
Parts can run out the back or front of the press with the same
drive. The system also is well-suited to presses with rolling
bolsters. As a common unit they may be mounted on the press and
can operate both bolsters when they are in operating position.
Because only the tray is in the area of slug removal, the conveyor
can have a very low profile. The Shuffle Drive also can be used
for pit conveyors or floor-mounted systems because it is a horizontal-motion
handling system and can transmit the motion several hundred feet
with only one drive. Trays are self-cleaning as they slide the
material along, with no oil or scrap carryover, which keeps the
work area cleaner.
Magnetic Conveyors
Magnetic conveyors can be used for applications involving ferrous
materials. Typically, a magnetic converyor has a belt with magnets
mounted to it and moves under a sheet of stainless steel. When
the tray comes to the end, the belt with the magnets turns away
from the stainless sheet, causing the material to fall. For safety,
most moving parts are within the frame of the conveyor.
These conveyors can move material vertically and even upside down
if the weight of the product allows it. By design, they do not
have a low profile and cannot be moved around manually during
die changes.
Gravity
A gravity system is a good tool when used properly and when designed
far enough ahead to suit the product range. In this type of system,
a hole in the bolster allows scrap to fall onto a pit-mounted
or floor-mounted conveyor. The hole in the bolster weakens die
support, so some companies have changed back to solid bolsters,
moving the scrap to the back or front of the press for scrap removal,
which saves time.
Gravity also can be used to shed the scrap off the front or back
of the press if the shut height is high enough to allow for this.
Again, the scrap can go into bins or a pit conveyor under the
press. Care must be taken to ensure scrap does not get caught
in the scrap chutes and plug the opening.
In-floor Systems
In-floor systems reduce forklift traffic and mess on the shop
floor. The pits must be designed to ensure easy access for maintenence.
Pits also should have a drop from one end to the other to allow
tramp oil to gather in a sump for filtering or disposal. The pits
should be lined to ensure that no contaminants enter the soil.
In-floor systems can be under the press or at the end of the press,
with heavy floor plates on top to allow for lift truck traffic
to pass over.
Typically, hinge belt and trough conveyors are used with in-floor
systems.
The key factor in selecting a scrap removal system is that it
must increase press uptime by reducing setup and maintenance time.
A system that is inadequate for the process or is installed in
an area that is not easily reached for maintenance can only add
to production downtime.
Stamping
Journal Website
Shuffling the deck
By Ed Belitsky
Air shakers may be obsolete if a mechanical system developed by Canadian inventor Paul Tamlin lives up to promises in reliability.
A simple mechanical system may be the answer to common pressroom problems. The Shuffle Drive from Press Room Techniques Inc. is a reliable method of clearing finished components, as well as metal tailings, off the press table and into seperate bins. The system is completely mechanical.
It consists of an electric gear reduction motor turning a transmission that multiplies torque and varies the rate of rotation during each 360 degree turn of the output shaft. The shaft turns a hub which connects with a Pitman arm that propels a rocker shaft. This shaft pivots back and forth on another shaft that serves as an axle. Both shafts run the width of the press table.
Any number of steel trays can be clipped to the rocker shaft by means of precisely fitted blocks made of ultra-high molecular weight plastic that requires no lubrication and no maintenance for the life of the system. The trays are made long enough to catch the finished components and the pieces of scrap metal expelled from the press. It then moves them forward about 3.5 in. during each cycle until they get to the end and drop over the edge into steel bins.
The materials are propelled by means of a reciprocating motion that moves each tray gently to the end of the stroke, then reverses sharply, causing the contents to remain in place while the tray slides back the length of the stroke. It's a clever use of inertial force that causes the contents of the trays to stay put while the tray is pulled back to its starting position. It's just like Benny Hill yanking a tablecloth out from under a tabletop full of dishes without spilling anything.
The effect is quite startling as the contents of the trays move forward several inches during each cycle. It will work even if the trays are tilted upward by as much as 5 degrees. Furthur, it will work with weighty components and scrap that can total up to more that 225kg in weight.
It wouldn't take long for such weights to destroy a conveyor belt or overpower an air system.
BRAINCHILD
The Shuffle Drive is the brainchild of tool and die maker Paul Tamlin of Oakwood, Ont. It was born of his frustration with the component and scrap removal systems on presses in shops he worked in over the years as maintenance supervisor, preventive maintenance coordinator and as a consultant for industrial research and developments dealing with metal forming. All of this practical experience was put to good use when Tamlin decided that there had to be a better way. Obviously, what was needed was a system that would eliminate, or at least reduce, down-time due to service and maintenance of the conveyors in general use.
"I got to thinking about it and made some designs out of wood," he said.
"The toughest part of the design was the gearbox, where regular rotary motion had to be converted into a stroke with a speed differential built into the return lap. It took quite a bit of experimentation, but once I got that one right, the rest was easy. It's actually quite a simple machine."
Since simple usually translates into durable where things mechanical are concerned, the Shuffle Drive displays all of the advantages of a system that may very well outlast the press it is attached to.
Tamlin took his wooden design to a nearby machine/fabrication shop and hammered out a deal with them to supply the production end of the business.
Tamlin is currently in the process of setting up a dealer network to deliver the Shuffle Drive. He has had enquiries and sales on both sides of the Canada/U.S. border.
The Shuffle Drive comes in several power levels powering a standardized gearbox. The gearbox unit is designed with such a margin of durability that there are no immediate plans to increase its size or capacity. The motor used for a tray weight of up to 204kg is 3-hp, and 5-hp for tray weights up to 318kg.
Tamlin offers the following system for calculating tray weight to his customers: tray length X flat width of tray X thickness of tray material X .283, which is the weight of steel per cubic inch.
LONG LIFE
Tamlin points out that the bearings in his drive unit are rated for 25,000 hours at 500r/min while the unit does only 70r/min. The motor is rated for 20,000 hours before service at rated load. It's an inline reduction motor of cycloidal design with no gears and 500% overload rating.
During the weakest point of the stroke, the 1.5 hp unit produces about 363 kg pressure which increases just like the press does as it nears the end of its stroke. The weakest point of the unit is outside, where the connecting rod bolts on with a 1-in U.N.C. bolt with a shear limit of approximately 40,824kg.
The chain drive is a lambda #60 which requires no lubrication. Sprockets are #18 and #19 which are easily interchangeable. Switching the 19-teeth one with the 18-teeth will speed up or slow down the cycles. The chain and output shaft guards are made of 3/16in. steel.
The gears inside the drive unit operate in an oil bath and the weakest component there has a shear strength of 54,432kg.
In a situation where a customer wants the product and the scrap to be propelled from the back of the press to the front, the Pitman rod is disconnected at the drive and changed to the hole on the opposite side of the output hub to reverse the direction of material flow. Loosening the nut retaining the pitman arm is made easier by inserting a 1-in. dia. bar into a hole drilled in the side of the hub to steady it while torque is applied. The top shaft is of 1.25in. dia. and the bottom shaft is 1.50 in.
Both are made of cold-rolled steel mounted on 12-in centers supported by pillow blocks. They are up to 180in. long in some applications. Pillow blocks are ordinary Dodge babbitted sleeve bearings.
The Pitman (connecting rod) design on the drive unit features a 1-in. bore ball bearing tie rod rated for 600r/min. It runs at 70r/min. The tie rod ends on the system are a 1in. bore spherical and are joined by a 1in. 14t/in threaded steel rod. All of these components can be purchased off the shelf from local suppliers.
Trays are supported at the output ends by rollers, wheels or solid blocks of UHMW plastic. During a die change, the trays can be simply lifted off the shafts and replaced the same way since they're held in place by gravity.
The Shuffle Drive is mounted to the press on an angle plate mounted to the column.
As far as costs are concerned, Tamlin described one new job where his crew removed seven air shakers from the press and replaced them with one Shuffle Drive, reducing setup time and increased production because of system reliablity due to heavy-duty design. It also reduced use of shop air. Total cost ended up at about 45 percent of the cost of the system they replaced.
GOING LIVE
Plant engineering
manager Lou Grossi at DBG catches refrigerator hinge components
coming off production tray with Shuffle Drive inventor Paul Tamlin
looking on.
I donned safety glasses and ear plugs to watch the
installation of a Shuffle Drive at DBG (The De Biasi Group) on
Shawson Dr. in Mississauga, Ont. where a whole forest of giant
presses stamp out components for a variety of manufacturers. While
the new unit was being fitted to an idle press, the one next to
it was stamping out components for refrigerator door hinges. We
watched as the componenets advanced 3.5in. at a time to the end
of the production bin. Other trays carried steel scraps which
dropped off the ends into a hopper where they were collected for
the recyclers.
DBG's plant engineering manager Lou Grossi said he was pleased
with the way the unit worked and looked forward to seeing more
of them in the plant.
He said, "DBG is a company that is always looking for innovative
applications in all areas of manufacturing. We plan to have five
Shuffle Drive units operational by the end of May."
The cost of the drive unit before installation is in the area
of $7,000.
Obviously the Shuffle Drive is a work in progress and is evolving
to fit specific applications as it goes along.
Tamlin points out that his conveyor will work equally well for
moving potato chips toward the packaging line or hot forged components
weighing hundreds of pounds toward an assembly area. The food
industry may be interested in the fact that the trays can be fabricated
of easy-to-sanitize stainless steel. The principle works equally
well for all of them, and in that respect, it has to be viewed
as a versatile conveyor that can be adapted to moving anything
in any direction with a maximum of efficiency and a minimum of
complications.
Metal
Working Website
SHUFFLE DRIVE Conveyor Systems
By Press Room Techniques, Inc.
In the world of material handling, there is now another system for the customer to choose. It may appear to be a choice between the tortoise and the hare when seeing the systems operate, as the operating speed of the Shuffle Drive is slower when compared to a vibrating trough conveyor, but the product movement rate can be the same.
The Shuffle Drive System was developed and patented by Paul Tamlin of Press Room Techniques. Almost 25 years in metal stamping environment, starting out as a Tool & Die maker, has given him an opportunity to understand different systems, and how a better one could be built.
The basic idea is very similar to pulling the table cloth out from under the dishes on a table but at a rate of 70 times a minute. When the tray moves forward with the product on it, it is accelerating and then quickly returns at a different rate of speed, causing the material on the tray to slide ahead approximately 3 inches or more every stroke.
Shuffle Drives are used in two different ways as described below:
1. Heavy duty press mounted scrap and part removal system
2. Bulk material handling system of different products from paint sludge to foundry applications with 1500 degree parts to metal stamping scrap under a line of stamping presses.
In a market where the competition is tough, you need to be able offer something different than what other manufacturers are doing.
600 ton press with
144 x 60 inch bed with a Model 10 Shuffle Drive
| bringing scrap off back side of bolster
Press-Mounted Part
and Scrap Removal Systems:
Some companies are presently still removing scrap manually from
automatic presses. If the press is required to shut off for this,
you lose money through inefficient production.
Some of the systems that are being used are belt conveyors, air
blast systems, air shakers, vibrating trays, steel hinge belt
and magnetic belt conveyor, and of course now we also have the
Shuffle Drive System.
The heart of every system by Press Room Techniques, Inc., whether
it is a press-mounted scrap removal system or a large scrap handling
system under a line of presses, is the Shuffle Drive gear box.
The idea, as it was conceived, was to develop a simple, efficient
scrap handling system for the stamping industry.
The system consists of a Shuffle Drive unit typically mounted
to any column of the press and can be set to move the scrap in
whichever direction you want. The press-mounted Shuffle Drives
come in 1 horsepower up to 5 horsepower with tray weights up to
1000 lbs. The scrap weight is 500 lbs. On the smallest unit, up
to well over 2000 lbs., which exceeds most stamping press capacities.
With the unit mounted on the column, it can be set up also to
operate rolling bolsters with the same drive, which reduces costs
and setup time. The drive then provides the power to the pivoting
cross shaft by a self-aligning connecting rod which has 1 inch
bore spherical rod ends for durability. The pivoting cross shaft
(which is the length of the bolster) is what the trays are attached
to by a high density plastic drive block. This provides a quiet
transmission of power and motion by a simple means that requires
no tools during die changeovers. The cross shaft is supported
by high density plastic pillow block bearings which require no
lubrication and provide long wear capabilities. Systems that have
been in operation for 4 years still show very little signs of
wear and are operating as installed.
300 ton press with
a 84 inch bed Model 7 Shuffle Drive 2 axis system operating a
tray that goes
left to right in bolster dropping scrap onto a tray that runs
front to back between feeder and press.
During a die changeover on a conventional stamping
press, all the operator does is lift the trays from the patented
cross shaft system and slide them out. There are no tools required
and so no time is wasted trying to find them. The systems operate
quietly, as they are driven by an electric motor, eliminating
the need for daily maintenance or lubrication. The Shuffle Drive
systems are quite a bit heavier than the typical system. A unit
on a press with a 12 foot bed would weigh about 1100 lbs, but
since they are press-mounted and the press might weigh 150,000
lbs., it is not of any great concern. Since they stay on the press,
there is less chance of damage happening in case of removing and
reinstalling the system.
Systems can be set up to take parts out through the back and scrap
out the front or the end of the press, all with one drive unit.
You’re not limited by the direction of production.
Most companies see a significant reduction is setup time due to
the ease of use. In the last 4 years, systems have been installed
on presses from 60 tons with a 24 inch bed to a 4000 ton press
with a 326 inch bed.
The 4000 ton has 5 hp model 10 Shuffle Drive moving 3 trays 40
feet long (approx. 900 lbs). On presses this size, the downtime
cost is very high and the customer needs a very durable low profile
scrap removal system.
Reasons to justify the purchasing of Shuffle Drive Systems are
maintenance savings such as no belt replacement, no air consumption,
reduction of setup time and flexibility of the systems.
4000 ton press with 326 inch bed Model 10 – 5 hp Shuffle Drive operating 3 trays approx 900 lbs in weight
The advantages for
press mounted systems are:
1. Quiet operation
2. No daily maintenance required
3. Very heavy duty designed for 24 hours a day 7 days a week
4. Operators like them due to reliability and ease of use
5. Companies typically will see an increase in production due
to reduced maintenance and set up times
6. Can be used on extremely low clearance applications
7. Quickly adaptable to different dies by using simple trays
8. System is not easily damaged by towmotor/lift trucks
9. No air required
Bulk Material Handling Systems:
The flexibility of the Shuffle Drive allows a wide variety of
systems to all be driven by one drive. Load ranges vary from only
a few pounds a minute up to 60 ton an hour or higher on custom
systems. Systems will basically consist of a drive suitable for
the application, a tray suspension system and a tray contour to
meet the customers handling requirements. Long systems are fabricated
in 14 foot sections for handling convenience and for ease of installation.
A 100 foot conveyor can be installed by 4 workers and be operational
in as little as 4 hours. Custom systems can be designed with trays
up to 8 feet wide by whatever length the customer requires.
Stamping oils have little effect on the operation of the system
as the trays are designed to be self cleaning and environmentally
friendly. Since the systems are non vibrating, they can also move
material in which you want no damage. They are ideal candidates
for situations where it is not easy to maintain equipment (due
to fewer moving parts). The only area that requires lubrication
is the connecting rod bearing which can be set up with an automatic
greaser. The drives can be placed anywhere throughout the length
of the system to provide the best access for maintenance.
Advantages of Shuffle Dive Conveyor
Systems are:
1. Tray sections can be sealed during assembly so no oil will
leak onto floor, this can allow for a collection of oil to be
recycled for a further savings
2. No carryover of material on bottom side as on belt conveyors,
reducing the cleanup required to keep floors clean.
3. Even if a system has a direction change, one drive can be adapted
to go multiple directions
4. Minimal wear points and slow operation mean extremely low maintenance
as there is no place for product or scrap to get caught
5. High load capacity due to design characteristics
6. Non-vibrating / slow operating speed means system is less likely
to cause damage to the structure
7. Systems are quiet to operate as there are no metal-to-metal
contact points
8. Standard rate of speed is approx 20 feet per minute, which
can be increased or decreased
9. High load starting capability
Press Room Techniques, Inc. has dealers throughout North America,
who can assist customers in picking the right Shuffle Drive system
for their application, whether it be a press-mounted system or
a material handling system. Press Room Techniques, Inc. has consistently
been able to satisfy customers who have had systems requiring
high maintenance costs by designing them a durable, simple system
which suits their needs.
SHUFFLE DRIVE SYSTEMS IN OPERATION
“United Tool & Eng. Co. remains competitive in today’s marketplace
by using the latest technologies available. In the past we removed
scrap from the presses with conveyors. They are cumbersome and
“one size” does not fit all applications.
“Press Room Techniques “Shuffle Drive System” has proven to be
more reliable, more versatile, maintenance free and “one size
fits all.” The only variable is the scrap tray. They are inexpensive
to make and install in seconds. The end result is more up time
and less cost to our customers for producing their parts.
“We have installed five systems so far and anticipate more in
the near future.”
Rod C. Meade President
United Tool & Eng. Co.
South Beloit, IL
“The Dana Canada Inc. Frame Plant in Thorold Ontario Canada had
been making car & truck frames since the late 1960’s. Currently
our facility stamps & assembles the entire Ford “F” series 250,
350, 450 & 550 truck frames. When you stamp & build large truck
frames you need large equipment to process the large parts and
you end up with heavy slugs and trim from the different processes.
In Thorold we have over 40 presses ranging from 400tons to 4000tons
with rolling bolsters that are 72” x 326”. Getting rid of the
heavy slugs and trim has always been a job almost in itself.
“I saw a picture of Press Room Techniques Inc. Electric Shuffle
Drive and thought it was worth at least the phone call. Paul Tamlin
came in and assured me that he could build a system that would
give us the reliability that we need for running 24/7 and robust
enough to never let us down
“The 2000 ton press has had the Shuffle Drive in it for well over
16 months and shows no signs of stopping. I installed our second
system into the 4000 ton press in October 02, and we will be taking
delivery of our 3rd and 4th Shuffle Drives within a week. It is
amazing to watch how such a simple and compact system can move
so much material consistently and never break down. Die changes
are simple and easy, and there has been no maintenance required
by either of the systems that are running. I highly recommend
the Shuffle Drives to anyone that needs to move scrap or product
quickly easily and in a very affordable manner.”
Ed Michalczyk, Tooling & Process Engineer
Dana Structural Solutions Division
Automotive Systems Group
Dana, Canada
Press Room Techniques Inc.
52 Walsh Road, R.R. #3, Lindsay, Ontario, Canada K9V 4R3
Phone: 1-888-284-3982 (for a dealer near you) Fax: (705) 328-3307
E-mail: sales@pressroomtechniques.com
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