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Kurt Vise Towers With CarvLock Clamping
System Provide Flexible Workholding For
FMS At Teleflex (Canada) Ltd. - - Machinable Vise Jaws Have .001" Repeatability
Richmond, British Columbia: Vise towers have been used for more than
a decade as a method for maximizing machining center output while providing
flexibility for handling changing part requirements. When equipped with
the latest fast-loading workholding, vise towers provide a bridge between
one and two station clamping setups and dedicated multiple station tooling.
Teleflex (Canada) Ltd. is a diversified manufacturer of Fluid Controls
and Diesel Engine Preheating Devices for large trucks, bus es,
coaches and some off-road vehicles. ISO 9001 certified in 1998, Teleflex
sells its products in over 30 different countries. Since most of these
products require precision machined components and producing them quickly
in small to medium quantities (300 to 10,000 parts), the company utilizes
a Flexible Manufacturing System (FMS) employing new Kurt CarvLock Vise
Towers. (Photo One)
Photo One Caption: Teleflex Proheat X-45 diesel truck
engine pre-heater. It prevents unnecessary engine idling and greatly reduces
air pollution and fuel consumption.
Walter Voros, manufacturing development manager for Teleflex (Canada),
said his company chose the Kurt CarvLock vise tower setup because it was
the easiest and fastest way to expand the part-holding capabilities of
its three-machine FMS and provides vibration dampening as no other product
today. Dedicated tooling is considerably more expensive to design and
build. Teleflex builds its own dedicated tooling in-house, but Voros said
Teleflex wanted a way to bridge the gap between short and long runs (10,000
to 20,000 parts). The eight station Kurt vise tower for the FMS was the
answer. These setups provide maximum machine utilization for flexible
manufacturing systems with high spindle speeds and handle a wide variety
of part shapes and sizes. (Photos Two and Three)
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Photos Two and Three Captions: Holding 8 parts
per loading, the Kurt CarvLock Vise Tower provides flexibility to
quickly and easily handle many size parts and configurations. Walter
Voros, manufacturing development manager for Teleflex, recently
added a second vise tower setup to the FMS.
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FMS Has Three HG400 II Hitachi Seiki Machining
Centers With 32 Pallet Stations And Automated Guided Delivery Vehicle
The Teleflex FMS cell's HG400 II horizontal machining centers with one-degree
table indexing are set up for machining a wide range of parts. The three
identical machines have a 22" x 23" x 20" work envelope with cutting feeds
of 590 ipm and spindle speeds of 12,000 rpm. These are high accuracy machines
(+/- 0.00012" / full stroke) with repeatability of (+/- 0.00008"). The
machines have Hitachi's Sigma 10M control, a 1.2 Gigabytes data server
for extended program storage, automatic measuring system, complete adaptive
control with tool life management, through spindle high-pressure coolant
and a 120-tool storage capacity.
The Teleflex FMS was designed for machining precision aluminum parts
for the company's two product families which include evolving product
designs and varying volume requirements. "As new part designs enter the
picture," says Voros, "we usually start by machining parts from solid
materials and sand castings which are in most cases later replaced with
die castings, permanent mold castings, or investment castings. With Kanban
in place the FMS allows us to fill daily requirements in quantities from
one to several hundred parts with virtually no changeover time."
 Starting
with raw aluminum castings, a computer controlled delivery vehicle presents
fixtured castings to the first available Hitachi machine. Each machine's
custom program performs close tolerance three and four axes operations
including drilling, milling, tapping, boring and finishing operations.
The FMS controller assures that the machines do not have to wait for parts
as long as the operator loads a fixture and releases it to production
so that the delivery vehicle will deliver it to the next available machine.
A typical die cast aluminum part machined in the system is a 4-1/4" by
2-1/2" compressor cover with a cycle time of 5-1/2 min. per part and finish
accuracy of ?} 0.001. Exterior surfaces are finished machined and the cover
interior is cored out. On most Teleflex parts, large amounts of metal
removal is not usually required. (Photo Four)
Photo Four Caption: Rigid Kurt Vise Towers are made of
80,000 psi ductile iron and employ four different Quick Change Jaw Block
options and 3 EZ Lock jaw plate options. They provide a full range of
workholding setups, which setup quickly and maximize the capability of
today's high speed machining centers.
Kurt Eight Station Vise Tower Provides
Needed Rigidity Plus
Flexibility To Hold Many Different Parts
Most of the Teleflex parts machined in the FMS require point-to-point
precision tapping and boring with some contour milling. "Part rigidity
is very important with these operations because we're operating the system
aggressively," reports Voros. "We are running these machines up to 12,000
rpm at high feed rates and get much better than 0.001" roundness through
milling with circular interpolation. That is another reason we chose the
ductile iron Kurt CarvLock vise towers over aluminum workholding devices
because of their rigidity and stability. We don't have to worry about
vibration or chatter because the ductile iron jaw blocks together with
ductile iron vise bodies dampen any tendency to vibrate when aggressive
operations are called for."  (Photo
Five)
Photo Five Caption: Die cast parts machined by the FMS
include a wide variety of shapes and sizes. Part runs vary from a few
hundred to a few thousand of the same part.
Made of 80,000 psi ductile iron, these Kurt vise towers have a stiffness
of 2.5 times that of aluminum (the vibration damping of ductile iron is
20 times higher than aluminum).
To give its vise tower users optimal clamping choices, Kurt offers several
interchangeable jaw block and jaw plate options. The jaw block options
which can be indexed to any of four positions are:
1) 3 different height ductile iron jaw blocks.
2) 3 different height aluminum jaw blocks.
3) Jaw blocks equipped with standard hardened jaw plates.
4) Jaw blocks equipped with the Kurt "EZ Lock" quick change jaw plate
system.
The clamping accuracy of these jaw block/plate options is dependent on
the vise clamping mechanism and its accuracy. Insuring this, all vise
bodies in the CarvLock 6 inch Vise Tower employ the time proven Anglock?
design which assures that the moveable jaw does not lift. Also, vise beds
are hardened as are the jaw plates. Each vise has a semi-hard steel screw
which clamps quickly and easily by hand with a force up to 10,000 lbs.
that converts to precise, repeatable gripping force.
CarvLock Jaw Plate System Gives Teleflex
Choices For Different Part Machining Requirements And Reduced Setup Time
The Kurt vise towers used by Teleflex are also equipped with the Kurt
CarvLock quick-change jaw plate system including aluminum as well as hardened
steel jaw plates. Kurt presently offers 3 EZ Lock jaw plates in hardened
steel and 5 in aluminum. These options allow Teleflex equipment operators
to quickly set up part runs with jaw plates that are best suited for a
particular part.
For easy mounting, all versions slip over a pair and are tightened using
an allen wrench on the top face of the vise of square head pull studs.
The entire operation takes about 20 seconds per vise station compared
to 5 minutes using standard vises. (Photos Six and Seven) The jaw combinations
provide the correct selection and very fast setup for a particular part
run with jaw plate location accuracy of .0001". Machinable jaws can also
be used and in many cases eliminate the need for custom fixtures. And
once machined, they can be reused with confidence because of their repeatability.
FMS Vise Tower System Leads To Second Tower
And Plans For A Fourth Machining Center
"Our first Kurt vise tower using the CarvLock quick change carvable jaw
system has worked out so well that we've taken delivery of a second CarvLock
system," reports Walter Voros. "Where we were doing two operations on
one vise tower setup, we're now doing one operation on each of two vise
towers. That extends our volume potential with our three machine FMS to
meet just-in-time delivery requirements while minimizing in-process inventory.
We've nearly doubled the volume we can handle without needing to go to
permanent tooling on a growing number of parts."
Voros said that expansion of the FMS to four machines is a possibility
being considered as Teleflex's business continues to grow. "That's the
nicest feature of our FMS," Voros stated." Most of the components, including
the workholding, are modular and easily expanded or modified as the need
arises. Plus Kurt backs up their vises with a 10 year warranty -- something
we've never had to use in the 15 years we've been using their vises."
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