Merloni Elettrodomestici (Fabriano, Italy) acquired 50 percent of the shares
of the General Domestic Appliances (GDA), a leading UK appliance producer
known for its Hotpoint brand about 2 years ago.
When Merloni took over GDA's four UK plants, including the Kinmel Park, UK washing
machine plant, it decided it needed to increase efficiency and capacity of
its production facilities. After meeting with and considering several companies
within the industry, Merloni Elettrodomestici UK decided to rely on the long-lasting,
4-decade relationship between Corno
Marco Italia S.p.A and GDA.
Drum wrappers are rolled by an expanding mandrel
after being rotated 90 degrees. By means of an overhead
transfer system the pre-assembled wrapper is moved to
a station where it is lockseamed together.
"Our goals were [to create] superior components in design
and manufacturability, increase capacity, and address consumer issues from
previous designs," Cliff Large, global advanced engineering manager at
Merloni, explains. "All
of these targets have been achieved."
In order to help Merloni achieve its production goals, Corno Marco supplied and installed new washer drum and cabinet fabrication systems for Merloni's UK-based washer machine production facility.
Two fabrication systems were installed in the facility, one for washer drums and the other for cabinets. The entire washer drum fabrication system comprises five different lines that include drum-wrapper, front-flange, rear-flange, and seamed-drum manufacturing lines, and a drum assembly line. The cabinet fabrication system comprises two lines - the cabinet manufacturing and the cabinet assembly line.
To accommodate the new equipment, Merloni had to reconfigure its
plant layout and design. "We completely reengineered our manufacturing facility clearing
close to 50 percent of the factory area. This was partially achieved through
the decision to cease the manufacturing of dishwashers and radical redesign
in the new product requiring less components both from an internal manufacture
and purchase part count," explains Mr. Large.
The drum fabrication system has an average net productivity of 220 pieces
per hr, and depending on the configuration of and different types of material
thickness and spiders, can create a range of up to four different drum
models. All lines are said to be fully automated and are equipped with
its own hydraulic, pneumatic, and lubrication system. Each drum line features
an electric system developed by Siemens that includes a control board and
console, and I/O module.
In the drum wrapper line, steel is fed from a double-driven decoiler and straightening feeding unit to a hydraulic press-working station made up of six hydraulic press units and one shearing unit. Here, tooling for notches and piercings are performed and the material is also cut-to-length. A buffer station helps during times of equipment maintenance or downtime. The system then automatically stacks the wrappers on the proper pallets.
Both the front- and rear-flange lines operate in a similar fashion. Material is fed from the decoiler and electronic feeding unit to a hydraulic press. Tooling is performed from a double-action die, drawing the plate, outer trimmings, inner punchings, and inner and outer holes for both flanges. A driven conveyer then handles the plates and delivers them to the drum manufacturing line.
After the front- and rear-flanges are fabricated, the flat wrapper is then fed and bent into its proper shape at the seamed drum manufacturing line. After the wrapper's two edges are bent, the part is rotated 90 degrees and is moved to a station where it rolls along an expanding mandrel. The mandrel opens to align the edges of the part, and they are then seamed together.
An overhead transfer system then lifts the wrapper and transfers the part to a station, where it is held and rotated, while rollers flange the front and rear edges of the wrapper. Vanes are manually loaded onto a conveyer and are fed into an automatic system that organizes and places the parts into a jig. After the drum wrapper is placed onto the next station, the jig expands and moves the vanes into the wrapper slots. Simultaneously, the rear flange is moved and rotated to the correct position, and the drum wrapper and front flange are loaded on top of it. The pre-assembled drum is then moved to the next station, where the three parts are seamed together in two roll processes. The drum is then transferred to an additional station, where the front flange radial coinings are performed.
At the drum assembly line, the drum is loaded onto a self-aligning centering station that punches six holes in the bottom of the drum. Then, a conveyer moves the part, and a spider is centered into place by a jig. The drum is then loaded on top of the spider and fastened together by counter-sunk holes and is moved to a jig where an automatic system feeds and fastens screws on each of the spider arms. As a final step, the part is placed into a rotating compartment, where analog outputs are registered and transferred into information regarding the part's height, flatness, and concentricity.
With the washer drum system, all parts are automatically handled by several types
of machinery, including mono-beam overhead transfers, twin-beam side transfers,
pallet lines, and conveyers.
The automatic cabinet assembly line features five stations. Parts
are handled by a mono-beam overhead transfer system.
||A second system, which is dedicated to cabinet manufacturing, includes
a wrapper fabrication line and an assembly line. The first line forms
the cabinet into its correct shape, while the second fastens panels
and parts together. Both lines have an average net productivity of
220 pieces per hr and contain hydraulic, pneumatic, and lubrication
systems, as does the drum wrapper system.
the cabinet wrapper line, the cabinet is formed into the traditional "U" shape
with the use of three different press stations. First, material is
fed from a blank stock to an area where it undergoes perimetral blank
notching and is then moved to the several press stations. At the
first press, the part is bent, and grooves are imprinted into the
pre-painted steel on the back and sides. It is then moved by an automatic
loading and unloading system to the next press. Here, the part is
bent on the front side of the wrapper and undergoes punching and
piercing. The wrapper is then automatically loaded and unloaded to
the third station. At the third press station, the wrapper is bent
into its final "U" form and is then moved via a twin-bean transfer
system to the second line for final assembly.
At the final assembly line, the "U"-shaped cabinet
is transferred to the first station where two brackets are assembled
to the inner side of the cabinet. It is then moved to a pre-assembly
station where top frame parts are fastened. The cabinet is then
moved to a top assembly station where the top frame is fastened
and a bottom assembly station where the base panel is fastened
to the cabinet. At the final station, the top frame and base
panel are assembled for final use. Parts, transferred by a mono-beam
overhead transfer system with grippers and conveyers, move to
where top and bottom panels are assembled and fastened to the
cabinet. The finished cabinets are unloaded off the system line
by pay-off conveyers.
The two companies worked closely together while
developing the customized equipment system for Merloni's facility. "Corno Marco provided its experience in co-design, especially in the lifter assembly stations of the drum line to reach expected - and better - results in terms of functionality and flexibility," Mr.
In order to meet Merloni's goals, Corno Marco
developed, tested, and produced several versions of its equipment.
Mr. Tolot explains: "The design and manufacturing activities
have been focused on granting a high level of flexibility - introducing
different product versions, in various sizes and shapes, and
reducing significantly the production cycle time without making
important modifications affecting cost and time."
Using its new equipment, Merloni has achieved
its goals for the washer drum and cabinet fabrication systems
it set out to accomplish. In terms of advantages, Mr. Large said, "Superior
product, reduced service call rates, high level of automation
cost effective manufacture, increased capacity - 30 percent of
previous manufacturing area out producing the replaced manufacturing
processes - and reduced part count [are already being experienced]."
As the successful installation of equipment shows,
the relationship that first started with the GDA company 40 years
ago will continue as new management and projects are being coordinated
with the Merloni group. Mr. Large says, "We are already working
on a project to reduce the cycle time on existing equipment,
and Corno Marco is currently manufacturing a drum line for our
tumble dryer facility."
Adds Mr. Tolot, "The relationship with Merloni
is strong and lasting. More jobs are coming up for both tools
and equipment in laundry and cooking sectors."