Core Materials manages a heavy load

Core Materials a heavy load Core Materials moulding

industry;

impressive: maker parts

Navistar

discuss

Ohio,

it was only formed

17 years

almost

N

Corp (CMC) in Columbus, as the Columbus

has given

second

its new direction

in 1997. Plastics

it experience

to none. Amanda

manages is a relatively

But the company’s in-house

moulding

in the compression Weaver

since becoming

new name

visited

an independently

pedigree operation

moulding

the firm’s

in the SMC of truck

of industrial

Columbus

owned

is

plant to

business.

ot surprisingly the manufacture

The truck maker also continues to own

sales and marketing Steve Klestinec told

of components, such as truck bonnets, for Navistar still forms

44% of the shares in CMC. But the moul-

Reinforced Plastics. The manufacture

der has also lost no time exploring new business opportunities and investing in a

personal watercraft (PWC) for Yamaha is

an important

part of CMC’s business;

some $50 million worth of sales in 1997.

significant

expansion,

vice president of

of

also a significant business, and CMC also counts tractor makers John Deere and Case Corp amongst its customers. Growth is also on the agenda: most significantly through a new facility in Gaffney, South Carolina, which adds 9300 mz and 40 staff to the 30 000 m2 and 470 employees in Columbus. A 600 mm wide sheet moulding compound (SMC) machine was also installed in Columbus increasing compound production capacity by some 30% as well as allowing the production of speciality materials to meet demanding product specifications.

The core business

A combination of automated production volumes.

22

REINFORCEDplastics

and manual assembly techniques are used by CMC depending on

February

1999

Today CMC compounds some 18 000 tonnes of SMC a year, 85% of which is moulded in-house. The firm has four major formulations of SMC with minor modifications in, for instance, glass content to give some 20-25 different compositions. Ashland Chemical’s polyester resins and PPG’s glass fibres are used throughout. In addition to the new 600 mm SMC machine which is used to make speciality grades, for instance lightweight compounds containing glass bubbles, SMC is made on a 1200 mm machine. Typically CMC uses a compound with a glass reinforcement content of 27-28% which gives a good combination of strength - see front matter 0 1999 Elsevier Science Ltd. A// rights reserved.

0034-361719918

Core Materials

and surface finish.

manages a heavy load

However, it can make

and process SMC with up to 45% glass; mat and woven roving can also be incorporated to give greater strength. materials are used in parts requiring impact PWCS.

resistance

such

as

Such high

those

on

On the moulding side Klestinec says CMC offers a full service from design and specification of the part through mouldand primer painting, ing, assembly including just-in-time delivery to some customers. The company is also adapted t o do high and low volume production r anging from its semi-automated line to nnake

bonnets

for the

Navistar

truck

Fblant at Springfield through to speciali:zed work on the General Motors’ electric vehicle

(EV).

This flexibility is made possible by available in the range of presses Columbus: 17 William White, Hepburn and Wemhomer machines from 5004500 tonnes in size. “We have the largest SMC press in the USA and a significant percentage of the country’s total large press capacity,” says Klestinec. The Gaffney plant will also be equipped to perform a range of work. Some seven presses are already in operation including one of 3000 tonnes. Most presses, in both plants, are equipped for in-mould coating (IMC) and vacuum assisted processing.

“We have the largest SMC press in the USA and a significant

percentage

of the country’s total large. press capacity.”

CMC’s heritage as part of Navistar is apparent in its special capabilities to handle large parts: for instance a truck bonnet produced on a dedicated system capable of moulding 360 parts a day. Oversized platens on some of the presses also facilitate production of particularly large components.

Heavy truck parts, such as these bonnets, still comprise a large share of CMC’s business.

Jarvis Pige, product development manager at Columbus told Reinforced Plastics that CMC has some 180 live moulds between the two factories. These are used for production runs starting as low as 200 parts/year for some service parts. However, a more typical production run is in the 6000-65 000 parts a year. CMC tries to run each tool for at least two shifts before a change; two to three week runs of a part are typical and for particularly large jobs there are dedicated presses. Press cycle times in the plant are in the range of 90-120 sets. This means that some parts, for instance those for Yamaha, can be produced at a rate of 40-50 components per eight hour shift from a single tool. On the 4500 tonne press two tools can be run simultaneously increasing production rates still fur-

ther. A high volume truck part might well be produced at a rate of llO/shift. Assembly is rather faster, typically 130 parts a shift, meaning that five day shifts can be operated compared with seven day work patterns in the press shop. Significant use is made of robots in the handling and parts assembly areas. For instance a truck grille panel will be removed from the mould using a robot equipped with sucker pads. A robotized router is then used to cut the headlamp slots and grille opening. Computer controlled robots are also used to apply an adhesive (again all supplied by Ashland) to the components. However, the robotized assembly stations tend to be part specific and can only be justified if the production is high volume. For mid-range parts - such as a three piece bonnet made at a rate of 130

February

1999

REINFORCEDplastics

23

Core Materials

a day -

a more manual process is used.

Operators load the three skin parts and two reinforcements

reaction

injection

moulded

(SRIM)

A

robot then applies the adhesive.

EV production an excellent

ect is demonstrating its capacity to make class-A body panels. All external panels

early

range

development

strategy

has been

appears to be paying off. In May 1998 the company announced a business rela-

test bed for a

tionship with Case Corp for the manu-

New markets Although the majority of CMC’s work is for the heavy truck industry a novel proj-

it is still relatively

er its business

whole

a heavy load

days for CMC as an independent mould-

parts.

into the assembly

press which is closed hydraulically.

Although

manages

of composite

systems.

facture of tractor roof assemblies. This was extended three months later to include production of combine harvester roof assemblies from late 1998. The company has also established a new relation-

being made in a specialist department working a single shift system. Some sub-

The EV parts require a full class-A automotive surface, but even truck man-

ship with John Deere to produce bonnet assemblies for a new tractor model to

ufacturers are fussy about the appearance

assembly is also done on the vehicle

of their vehicles in the 1990s. Many of

enter production in mid-1999. New business away from the com-

before it is sent off to be top coated. Some 600 vehicles will be built between

CMC’s parts are produced using a GenCorp IMC applied under vacuum

mercial vehicle sector includes the production of residential door products for

June 1998 and August 1999, mainly for

which gives a sufficiently

customers in the southwestern USA. Pigge says that the EV production has been an excellent test bed for a whole range of composite systems. In addition to the SMC parts made by CMC, the vehicle also features resin transfer moulded (RTM) and structural

for immediate top coat painting. For non-coated parts, or those where the edges need additional finishing CMC is equipped with a paint priming line. CMC has to meet customer demands that 98.5% of parts comply with quality criteria first time round.

for the General Motors EV are currently

MmRS

good surface

Caradon

Doors

and

Windows

Inc’s

Peachtree Div, which will be fulfilled from the Gaffney plant. The financial benefits of the expansion are also being felt by the company. Its latest financial results show a 20% increase in turnover and a 56O/oincrease in profit. n

FOR GUSSFIBRE MOULDERS Thetankmixerhasa universal clamp to enable it to fit any 1 tonne bulk taok and its powerful variable

he in-drum mixer fits any steel drum with a 2” BSP bong hole and is used to mix pigments or additives into 200 L.

spedmotordrivingtwo &et blades makes-it ideal for mixing in pigments, fillets and additives or for gently agitating pigmented or l&d Pii Retardent resins which have settled doting storage.

KEG MIXER used for mixing pigments and additivea into gelcoats, ot likrs into 25 kg of resin.

PLEASE INSERT 337 ON READER RESPONSE CARDS

February

1999

REINFORCEDplastics