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Open moulders prepare for the future
Open moulders prepare for the future Open moulding today is like a summer picnic on the prairie with storm clouds gathering in the distance. Fabricators are enjoying the sunshine while keeping a wary eye on the turbulence to come. Equipment manufacturers are hawking new tents and umbrellas while material suppliers tout a variety of waterproofing agents. For those who prepare for changing weather, the picnic will go on. Others are destined to get wet. William K. Hamilton reports.
F
or o p e n
m o u l d fabricators, the
brewing storm clouds are regulations for styrene fumes a n d emis-
sions. Parts of Europe are already dealing with tight regulations for styrene while the storm clouds are m o v i n g across the Atlantic to Canada a n d the USA. Asia may be next. In Canada, n e w a n d potential future regulations are focused o n the e n v i r o n m e n t inside the plant. In its n e i g h b o u r ing c o u n t r y to the south, proposed regu l a t i o n s are focused o n emissions leaving the plant. The Ministries of Labour in five C a n a d i a n provinces have already adopted a 20 parts per m i l l i o n (ppm) o c c u p a t i o n a l exposure level (OEL) r e c o m m e n d e d by the American Conferences of G o v e r n m e n t Industrial Hygienists (ACG1H). That's a big drop from the current SO p p m standard in other provinces, a n d the 100 p p m standard in the USA. So far, only one province seems to be enforcing the new standard (Manitoba), a n d the C a n a d i a n Plastics I n d u s t r y Association (CPIA) has convinced other ministries to hold off for now, i n c l u d i n g the major industrial provinces of O n t a r i o a n d Alberta. Quebec, which also includes a substantial composites industry, has so far not m o v e d to change its current SO p p m standard. 18
REINFORCEDplastics
January 2001
In the USA, the E n v i r o n m e n t a l Protection Agency (EPA) will soon issue
sources must comply w i t h i n three years.
proposed regulations for styrene emissions. The EPA proposal, scheduled to be available by December 2000, was not yet released as this issue w e n t to press. (To watch for the proposal, check the regulatory a n d c o m p l i a n c e section of
the storm clouds are about four years away. l b their credit, most fabricators are n o t waiting for the first drops of rain. They are already busy working oil compliance. The solutions they are exploring follow three different paths. The quickest a n d easiest (but least desirable because it is the most expensive) is to
www.cfa.com, or the MACT Standards section of www.epa.gov.)
Parts of Europe are already dealing with tight regulations for styrene while the storm clouds are moving across the Atlantic to Canada and the USA. Asia may be next. Once the EPA proposal has been issued, the i n d u s t r y will have 60 days to c o m m e n t . T h e n the EPA will consider all c o m m e n t s a n d issue a final rule a b o u t a year after the original proposal. New maior sources of styrene emissions will t h e n have to c o m p l y by the effective date of the new rule or start-up, whichever is later, a n d existing major
For current operations, in other words,
capture a n d treat the styrene fumes. The second approach is to reduce or eliminate styrene fumes by using n o n a t o m i z i n g applicators a n d low- or nostyrene resins. This approach may be less expensive but requires learning the art of fabrication all over again. Veteran operators w h o have h o n e d their skills are n o t h a p p y with e q u i p m e n t and materials that d o n ' t work the same way as their tried and true methods. The third approach (for the right applications a n d for fabricators with access to the capital required) is to change to a closed m o u l d process and eliminate styrene fumes altogether. For most fabricators, the yellow brick road will be the one d o w n the middle - staying with open m o u l d i n g but m a k i n g a variety of changes to comply with the new standards. In a session o n the future of o p e n m o u l d i n g at the recent composites
0034-3617/01/$ - see front matter © 2001 Elsevier Science Ltd All rights reserved.
Open moulders prepore for the future
c o n v e n t i o n in Las Vegas, CFA director of technical services Bob Lacovara said, "The future is good, if y o u are willing to change." Betore saying that, however, he delivered a wake-up call. "You can't c o n t i n u e business as usual," he said. "Spray-up is dead." Lacovara a d d e d t h a t n e w tools are available today; the i n d u s t r y o n l y needs to incorporate them. He encouraged his audience to embrace the n e w t e c h n o l o gy. The following sections review a sampling of w h a t is available today.
New materials Both glass a n d resin m a n u f a c t u r e r s face t h e c h a l l e n g e of h e l p i n g their c u s t o m e r s reduce styrene fumes a n d emissions. For resin manufacturers, th,~ challenge is to p r o d u c e resins t h a t have low or n o styrene, yet p e r f o r m appropriately during production and t h r o u g h o u t the life of t h e f i n i s h e d part. Glass manufacturers, in turn, m u s t d e v e l o p a n d deliver p r o d u c t s t h a t work w i : h t h e new resins. Resin m a n u f a c t u r e r Reichhold, for example, is n o w i n t r o d u c i n g a n o t h e r specialty low-styrene resin, this one p u s h i n g styrene c o n t e n t below 33%. It's the latest in a series of low-styrene resins that reduces styrene c o n t e n t to a b o u t 3S%, from the s t a n d a r d of 4S-S0% or more. W h i l e those raw n u m b e r s m a y seem small, the percentage i m p r o v e m e n t s are significant a n d the emission reductions are substantial. The new resin, t r a d e m a r k e d DION VI'L 7100, is vinyl polyester w i t h strength, t o u g h n e s s a n d heat resistance properties t h a t c o m p a r e favourably with p r e m i u m vinyl esters. The p r o d u c t is also said to provide the viscosity a n d wetting p e r f o r m a n c e n e e d e d for h i g h quality lamination. "Generally, w h e n you take styrene out of a resin, physical properties go d o w n a n d cost goes up," says Warren Owens, senior director of m a r k e t i n g for Reichhold's N o r t h American C o m p o s i t e s Business. "But this new p r o d u c t has low VOCs (volatile organic c o m p o u n d s ) ,
with g o o d corrosion resistance a n d m e c h a n i c a l properties." "We set out to develop a versatile, cost-effective p r o d u c t for a p p l i c a t i o n s p r i m a r i l y in the corrosion segments," c o n t i n u e s Owens. "Low styrene was a m u s t a n d we m o r e t h a n achieved our objectives." Owens says Reichhold is also providing a couple of special services t h a t supp o r t its customers. It is actively representing the i n d u s t r y in talks with the EPA a n d o t h e r agencies c o n t e m p l a t i n g c h a n g i n g regulations. Reichhold is also
h e l p i n g customers learn m o r e a b o u t their processes a n d h o w to make changes to c o m p l y with new regulations a n d also i m p r o v e o p e r a t i n g efficiency. "Our customers include m a n y smalland m e d i u m - s i z e d c o m p a n i e s t h r o u g h out the country," says Owens. "We are being proactive in h e l p i n g t h e m get t h r o u g h key issues t h e y face in their business, a n d HAP (hazardous air pollutants) is a big one." Reichhold's l o b b y i n g efforts reflect the c o m p a n y ' s expertise in p o l y m e r s a n d adhesives. It makes sure regulators January 2001 REINFORCEDplastics
19
Open moulders prepore for the future
u n d e r s t a n d of what is achievable in the field, where conflicts of purpose may exist, and what the cost of c o m p l i a n c e
consolidate n o n - a t o m i z e d resin or gelcoat streams as they leave the tip of the nozzle. A large orifice eliminates
will be for the industry. At the same time, Reichhold's technical service peo-
plugging issues with filled resins or contamination. M a g n u m says the low-pressure sys-
"But 1 d o n ' t t h i n k a n y o n e is happy with the current generation of gelcoaters," says Sours. "Most of the current e q u i p m e n t is an a d a p t a t i o n of the flowtype application technology. We're working o n s o m e t h i n g conrpletely different."
ple are h e l p i n g customers evaluate process changes that can improve productivity a n d operating efficiency, as well as reduce exposures a n d emissions to c o m p l y with g o v e r n m e n t regulations. Other resin producers are also busy
tems offer the best emissions performance yet. Test data supplied by the company show substantially reduced emissions for resin a n d gel-coat w h e n compared to an airless/air assist chop
i n t r o d u c i n g new low-styrene products. At Composites 2000 in October, for example, AOC i n t r o d u c e d a new genera-
a n d gel-coating system. Venus Industries adds its own low pressure, internal mix systems for
Sours says his c o m p a n y is also selling more robotic e q u i p m e n t . The motivations for robots are productivity and c o n t r o l l i n g material use a n d thickness. "Robots are taking the h u m a n e l e m e n t out of production," notes Sours. "Robots do things consistently, and prod u c t i o n takes the same time every time."
tion of acrylic b o n d i n g resins that combine reduced styrene emissions with
e n h a n c e d e n v i r o n m e n t a l systems. The
Mel Saccomanno, engineering man-
c o m p a n y offers nozzles for traditional spray application as well as flow a n d i m p i n g e m e n t coating. Glas-Craft lnc, Indianapolis, Indiana, claims to have the next g e n e r a t i o n in n o n - a t o m i z i n g t e c h n o l o g y - the Delta V Force nozzle. The product is a single-orifice, directed-column nozzle for n o n atomized d i s p e n s i n g of resin. Testing at a major American university last year (May 2000) fotmd that the level of styrene emissions with impingem e n t - t y p e t e c h n o l o g y was 20% higher t h a n tests with the new Delta V Force nozzle from Glas-Craft.
ager for Aqua Glass in Adamsville, Tennessee, has first-hand experience w i t h the learning curve associated w i t h
higher t h r o u g h p u t s a n d the ability to increase filler loadings. Trademarked HyCryl C668 Series, the polyesters are engineered for spraying in open m o u l d processes.
New equipment The new word in open m o u l d i n g is 'applying' resin. The current trend is to move away from 'spraying.' Typical of the trend to n o n - a t o m i z e d dispensing of resin are the so-called flow coaters a n d i m p i n g e m e n t - t y p e nozzles. Flow-coat nozzles typically have a series of exit holes that produce a n o n atomized, linear c o l u m n of resin. While this m e t h o d reduces styrene emissions, early models were not good at dispersing glass fibre u n i f o r m l y in the laminate. h n p i n g e m e n t nozzles addressed that problem by having a wedge cut in the centre with two dispensing holes in the angles. The two c o h m m s of resin exiting the nozzle would intersect a n d develop a spray pattern. O n e of the leaders in i m p i n g e m e n t technology is M a g n u m Industries, Clearwater, Florida, which joined forces in a merger last September with Venus Industries, Kent, Washington. Subsidiaries of Graves Spray Supply lnc, M a g n u m a n d Venus c o n t i n u e to operate as u n i q u e entities for the short tern]. At the CFA show in October, Magnum featured its latest fluid i m p i n g e m e n t t e c h n o l o g y for resin a n d gel-coat. Frademarked FIT, the systems
20
REINFORCEDplastics January 2001
Styrene regulations elsewhere in Europe vary from country to country, but the trend is toward increasingly tight control standards. Lynn Sours, general manager, GS Manufacturing, says the state-of-the-art is good for resin a n d glass but still needs work for gel-coat application. "The guns for resin a n d glass are OK," says Sours. "There was a learning curve as the new guns put on too m u c h resin at first. Applicators had to adiust the glass application a n d get used to the feel of the new e q u i p m e n t . As a result, c o n v e n tional spray guns will soon be obsolete."
new materials and equit)ment. Speaking like an experienced politician t r y i n g to put the best face on a bad situation, he describes the experience of switching to new materials and processes as 'fairly difficult,' and 'a substantial challenge.' Some of the d i f f i c u l t y comes from team mates inside the company. "Our people had developed an expertise doing things a certain way," says Saccomanno. "Then we come along and ask t h e m to change. The old spray guns had a certain feel to them. There was some kickback they were accustomed to feeling. The new flow coaters feel more like a garden hose. That's n o t the same feel a n d they had to change their technique." W h e n the e q u i p m e n t was first changed, S a c c o m a n n o says p r o d u c t i v i t y w e n t d o w n . As his team mates b e c a m e more c o m f o r t a b l e with the n e w equipm e n t , p r o d u c t i v i t y w e n t back up to pretty m u c h what it was before the change. In Europe, the most stringent regulations for styrene are in Scandinavia, where 20 p p m has been the standard for several years. New factories built today must n o t exceed 10 ppm, and they cann o t be built w i t h i n 4S0 m of a residential area. Styrene regulations elsewhere in Europe vary from c o u n t r y to country, but the t r e n d is toward increasingly tight
Open moulders prepare for the future
Magnum's FIT technology uses the impingement of two fluid streams to form the pattern,
control standards. There is hope, especially a m o n g fabricators in countries with an already stringent standard, t h a t all counties in the European U n i o n will a d o p t the same s t a n d a r d a n d avoid having a n y c o u n t r y suffer a c o m p e t i t i v e disa d v a n t a g e for r e d u c i n g emissions. Given the tight standard in Scandinavia a n d p e n d i n g t o u g h e r regulations in o t h e r European countries, it s h o u l d be n o surprise to find t h a t fabricators are l o o k i n g m o r e at c l o s e d - m o u l d processes like v a c u u m bagging, resin transfer m o u l d i n g (RTM) a n d v a c u u m
22
REINFORCEDplastics January 2001
assisted RTM. But a m a j o r i t y still uses the spray-up process and is expected to cont i n u e to do so for the next several years due to the low cost a n d high speed of the spray-up process. O n e of the leaders d e v e l o p i n g a n d p r o d u c i n g low-styrene e q u i p m e n t is Aplicator System AB of Sweden. According to sales vice president ClasAke J o h a n s s o n , the c o m p a n y has m a d e a n u m b e r of design changes that reduce styrene emissions, l:or exalnple, its glass fibre c h o p p e r gun mixes resin a n d catalyst inside the gun to reduce fumes.
Aplicator r e d u c e d t h e a m o u n t of solvent n e e d e d for c l e a n i n g the gun by using a small m i x i n g t a n k a n d p l a c i n g it close to t h e h e a d of t h e spray gun to m i n i m i z e t h e l e n g t h of the t u b e from m i x i n g t a n k to spray nozzle. The gun also m i n i m i z e s the s o l v e n t n e e d e d for f l u s h i n g the system by i n t r o d u c i n g c o m p r e s s e d air. The restllting t u r b u lence accelerates t h e c l e a n i n g a c t i o n of t h e s o l v e n t a n d lessens t h e a m o u n t needed. "All of the new m a c h i n e s use very m i n o r quantities of acetone," says Johansson. A n o t h e r system p o p u l a r in Europe for r e d u c i n g styrene e m i s s i o n s in o p e n m o u l d i n g is the resin roller dispenser. The roller, l o o k i n g very m u c h like a p a i n t roller, e l i m i n a t e s t h e bucket a n d brush of h a n d lay-up by d i s p e n s i n g catalyzed resin directly into t h e m o u l d w i t h o u t spray or h a n d m i x i n g . The system ( s o m e w h e r e b e t w e e n s p r a y - u p a n d t h e closed m o u l d processes) has q u i c k l y b e c o m e a best seller in the industry. Wolfangel G m b H recently introd u c e d a new gel-coat spraying system that redtices the a m o u n t of solvent required for cleaning. "Changing colour is simply a m a t t e r of c h a n g i n g the connector," says Roll Wolfangel. "No solvents or o t h e r cleaning liquids are required, even w h e n c h a n g i n g from black to white. This saves precious w o r k i n g t i m e a n d keeps the use of e n v i r o n m e n t a l l y undesirable solvents to an absolute m i n i m u m . "
New processes There is no q u e s t i o n t h a t some o p e n m o u l d fabricators are also looking at closed m o u l d alternatives. The most p o p u l a r o p t i o n s seem to be the lessc o m p l e x variations of the injection a n d infusion m o u l d i n g processes, such as P,TM, VARTM a n d v a c u u m bagging, and also cold c o m p r e s s i o n m o u l d i n g . Virtual Engineered C o m p o s i t e (VEC) t e c h n o l o g y is certainly a n o t h e r m u c h talked-about alternative to open m o u l d i n g . (See the D e c e m b e r 2000 isstie
Open moulders prepore for the future
of Reinforced Plastics for details a b o u t how G e n m a r converted from o p e n m o u l d i n g to VEC t e c h n o l o g y for its Glastron a n d Larson brands of pleasure boats.) Premix Inc, North Kingsville, Ohio, a t h e r m o s e t m o u l d e r a n d producer of sheet m o u l d i n g c o m p o u n d s (SMC), is promoting its own low-pressure, low t e m p e r a t u r e SMC system to open m o u l d fabricators. The c o m p a n y sees the t e c h n o l o g y as a way to develop new customers a n d grow the market for SMC. Its patented OpTorr process can be used with p o l y m e r a n d other low-cost t o o l i n g alternatives at 100 psi a n d cure at 93°C. To p r o m o t e the process, Premix works with ()pen m o u l d fabricators to develop an e c o n o m i c analysis comparing existing p r o d u c t i o n with the OpTorr process. If the fabricator decides to change to OpTorr, Premix will work with t o o l i n g makers a n d others to deliver a t u r n k e y process. Soli Dastur, Owens C o m i n g leader for market d e v e l o p m e n t services in Asia Pacific, sees evidence of a shift from o p e n - to c l o s e d - m o u l d processes in Japan, primarily driven by c o n c e r n s a b o u t r e d u c i n g styrene fumes a n d emissions. Elsewhere in the region, Dastur sees o n l y slow m o v e m e n t to closedm o u l d processes a n d the drivers there are material c o n s i s t e n c y a n d p r o d u c t quality. "With low labour cost and low volu m e production, most fabricators are using h a n d lay-up," says l)astur. "A few fabricators - those m a k i n g bus bodies a n d coolhrg towers, for example - are using spray-up to achieve a better finish a n d make parts faster."
The debate continues Meanwtrile, i n d u s t r y associations like CFA a n d CP1A c o n t i n u e to work with n a t i o n a l a n d provincial officials o n future regulations. CPIA Director of Composites C o u n c i l Jerry 1)wyer, for example, is hard at work talking with provincial Ministries of Labour a b o u t tire feasibility of
24
REINFORCEDplastics
January 2001
more s t r i n g e n t regulations for styrene exposures inside composites factories. "For most fabricators, a 20 p p m s t a n d a r d is n o t achievable e c o n o m i c a l ly," says Dwyer. "Open m o u l d fabrication is n o t a high-tech business. Most fabricators d o n ' t have the f i n a n cial resources to achieve the lower standard." Dwyer says the open m o u l d process is the largest category of composites fabrication in Canada, a c c o u n t i n g for 65-70% of all composites production. That's why tire trend to a more stringent exposure level is CPlA's n u m b e r one focus at the nlonlent. "The lower exposure levels are a bigtime threat to the composites i n d u s t r y in Canada," says Dwyer. "It's the hot b u t t o n right now." Dwyer says the association is d o i n g two things. O n e is e d u c a t i n g Labour ministers a n d others a b o u t the safety of the c u r r e n t 50 p p m standard, tire second is s e n d i n g letters to fabricators letting t h e m k n o w w h a t is h a p p e n i n g . "Sometimes the fabricators d o n ' t even know about the situation," says Dwyer. "We encourage t h e m to write to local officials to let t h e m know the potential impact o n their business." The debate also c o n t i n u e s in the USA. "As the proposed regulations stand now, they pretty muctr dictate that we put in a n incinerator," says Saccomano. "We d o n ' t agree with that approach. We d o n ' t t h i n k that's a viable way to go economically, a n d we d o n ' t t h i n k it makes sense w h e n you look at the whole s i t u a t i o n from an e n v i r o n m e n t a l perspective." In addition to adding cost, S a c c o m a n o says i n c i n e r a t i o n creates a s i t u a t i o n that is worse t h a n the original problem. "Our styrene emissions are very low to begin with," he says, "and to m i n i m i z e exposure levels inside, our v e n t i l a t i o n system moves a lot of air t h r o u g h the plant. We will need to m o v e a lot of air t h r o u g h the flame a n d b u r n a lot of n a t u r a l gas to i n c i n e r a t e the small a m o u n t of
Employers may benefit from process changes W h i l e the need to reduce exposure levels a n d e m i s s i o n s is p r o m p t i n g m o s t open mould fabricators to
look at process changes, the changes m a y p r o d u c e a n a d d i t i o n a l benefit in helping employees.
them
hire
and
retain
"Customers tell m e t h e y have a p r o b l e m g e t t i n g people to work for t h e m , a n d t h e n k e e p i n g t h e m o n c e they are o n the payroll," says Ron Adams, sales representative for O w e n s Coming. "Chemical exposures are o n e of the reasons." "A c u s t o m e r r e c e n t l y asked us to c o m e i n to c o n s u l t with t h e m a n d make r e c o m m e n d a t i o n s . T h e y have experienced 100% t u r n o v e r (change i n p e r s o n n e l ) d u r i n g the past eight months. Adams says t h e e m p l o y m e n t issue is p r o m p t i n g s o m e fabricators to seriously c o n s i d e r c h a n g i n g to a closed m o u l d process t h a t is cleaner a n d requires fewer people. Styrene regulations may be the major driver p r o m p t i n g fabricators to look at alternatives to o p e n moulding, but p r o v i d i n g relief from the e m p l o y ment
headache
might
be a close
second.
styrene in that air. In essence, we will be t u r n i n g styrene emissions i n t o a m u c h larger v o l u m e of g r e e n h o u s e gas enrissions." To i n c i n e r a t e styrene efficiently, process engineers will w a n t to c o n c e n trate the chemical in the air. But to conrply with O c c u p a t i o n a l Safety a n d Health Act (OSHA) regulations for exposure inside the plant, those same engineers have spent years i m p r o v i n g ventilation a n d diffusing the styrene in the air. S a c c o m a n o says the i n d u s t r y will c o m p l y with whatever the final rule t u r n s out to be, b u t in the m e a n t i m e they will kee t) t r y i n g to get the regulators to c h a n g e their minds. •
F
or o p e n
m o u l d fabricators, the
brewing storm clouds are regulations for styrene fumes a n d emis-
sions. Parts of Europe are already dealing with tight regulations for styrene while the storm clouds are m o v i n g across the Atlantic to Canada a n d the USA. Asia may be next. In Canada, n e w a n d potential future regulations are focused o n the e n v i r o n m e n t inside the plant. In its n e i g h b o u r ing c o u n t r y to the south, proposed regu l a t i o n s are focused o n emissions leaving the plant. The Ministries of Labour in five C a n a d i a n provinces have already adopted a 20 parts per m i l l i o n (ppm) o c c u p a t i o n a l exposure level (OEL) r e c o m m e n d e d by the American Conferences of G o v e r n m e n t Industrial Hygienists (ACG1H). That's a big drop from the current SO p p m standard in other provinces, a n d the 100 p p m standard in the USA. So far, only one province seems to be enforcing the new standard (Manitoba), a n d the C a n a d i a n Plastics I n d u s t r y Association (CPIA) has convinced other ministries to hold off for now, i n c l u d i n g the major industrial provinces of O n t a r i o a n d Alberta. Quebec, which also includes a substantial composites industry, has so far not m o v e d to change its current SO p p m standard. 18
REINFORCEDplastics
January 2001
In the USA, the E n v i r o n m e n t a l Protection Agency (EPA) will soon issue
sources must comply w i t h i n three years.
proposed regulations for styrene emissions. The EPA proposal, scheduled to be available by December 2000, was not yet released as this issue w e n t to press. (To watch for the proposal, check the regulatory a n d c o m p l i a n c e section of
the storm clouds are about four years away. l b their credit, most fabricators are n o t waiting for the first drops of rain. They are already busy working oil compliance. The solutions they are exploring follow three different paths. The quickest a n d easiest (but least desirable because it is the most expensive) is to
www.cfa.com, or the MACT Standards section of www.epa.gov.)
Parts of Europe are already dealing with tight regulations for styrene while the storm clouds are moving across the Atlantic to Canada and the USA. Asia may be next. Once the EPA proposal has been issued, the i n d u s t r y will have 60 days to c o m m e n t . T h e n the EPA will consider all c o m m e n t s a n d issue a final rule a b o u t a year after the original proposal. New maior sources of styrene emissions will t h e n have to c o m p l y by the effective date of the new rule or start-up, whichever is later, a n d existing major
For current operations, in other words,
capture a n d treat the styrene fumes. The second approach is to reduce or eliminate styrene fumes by using n o n a t o m i z i n g applicators a n d low- or nostyrene resins. This approach may be less expensive but requires learning the art of fabrication all over again. Veteran operators w h o have h o n e d their skills are n o t h a p p y with e q u i p m e n t and materials that d o n ' t work the same way as their tried and true methods. The third approach (for the right applications a n d for fabricators with access to the capital required) is to change to a closed m o u l d process and eliminate styrene fumes altogether. For most fabricators, the yellow brick road will be the one d o w n the middle - staying with open m o u l d i n g but m a k i n g a variety of changes to comply with the new standards. In a session o n the future of o p e n m o u l d i n g at the recent composites
0034-3617/01/$ - see front matter © 2001 Elsevier Science Ltd All rights reserved.
Open moulders prepore for the future
c o n v e n t i o n in Las Vegas, CFA director of technical services Bob Lacovara said, "The future is good, if y o u are willing to change." Betore saying that, however, he delivered a wake-up call. "You can't c o n t i n u e business as usual," he said. "Spray-up is dead." Lacovara a d d e d t h a t n e w tools are available today; the i n d u s t r y o n l y needs to incorporate them. He encouraged his audience to embrace the n e w t e c h n o l o gy. The following sections review a sampling of w h a t is available today.
New materials Both glass a n d resin m a n u f a c t u r e r s face t h e c h a l l e n g e of h e l p i n g their c u s t o m e r s reduce styrene fumes a n d emissions. For resin manufacturers, th,~ challenge is to p r o d u c e resins t h a t have low or n o styrene, yet p e r f o r m appropriately during production and t h r o u g h o u t the life of t h e f i n i s h e d part. Glass manufacturers, in turn, m u s t d e v e l o p a n d deliver p r o d u c t s t h a t work w i : h t h e new resins. Resin m a n u f a c t u r e r Reichhold, for example, is n o w i n t r o d u c i n g a n o t h e r specialty low-styrene resin, this one p u s h i n g styrene c o n t e n t below 33%. It's the latest in a series of low-styrene resins that reduces styrene c o n t e n t to a b o u t 3S%, from the s t a n d a r d of 4S-S0% or more. W h i l e those raw n u m b e r s m a y seem small, the percentage i m p r o v e m e n t s are significant a n d the emission reductions are substantial. The new resin, t r a d e m a r k e d DION VI'L 7100, is vinyl polyester w i t h strength, t o u g h n e s s a n d heat resistance properties t h a t c o m p a r e favourably with p r e m i u m vinyl esters. The p r o d u c t is also said to provide the viscosity a n d wetting p e r f o r m a n c e n e e d e d for h i g h quality lamination. "Generally, w h e n you take styrene out of a resin, physical properties go d o w n a n d cost goes up," says Warren Owens, senior director of m a r k e t i n g for Reichhold's N o r t h American C o m p o s i t e s Business. "But this new p r o d u c t has low VOCs (volatile organic c o m p o u n d s ) ,
with g o o d corrosion resistance a n d m e c h a n i c a l properties." "We set out to develop a versatile, cost-effective p r o d u c t for a p p l i c a t i o n s p r i m a r i l y in the corrosion segments," c o n t i n u e s Owens. "Low styrene was a m u s t a n d we m o r e t h a n achieved our objectives." Owens says Reichhold is also providing a couple of special services t h a t supp o r t its customers. It is actively representing the i n d u s t r y in talks with the EPA a n d o t h e r agencies c o n t e m p l a t i n g c h a n g i n g regulations. Reichhold is also
h e l p i n g customers learn m o r e a b o u t their processes a n d h o w to make changes to c o m p l y with new regulations a n d also i m p r o v e o p e r a t i n g efficiency. "Our customers include m a n y smalland m e d i u m - s i z e d c o m p a n i e s t h r o u g h out the country," says Owens. "We are being proactive in h e l p i n g t h e m get t h r o u g h key issues t h e y face in their business, a n d HAP (hazardous air pollutants) is a big one." Reichhold's l o b b y i n g efforts reflect the c o m p a n y ' s expertise in p o l y m e r s a n d adhesives. It makes sure regulators January 2001 REINFORCEDplastics
19
Open moulders prepore for the future
u n d e r s t a n d of what is achievable in the field, where conflicts of purpose may exist, and what the cost of c o m p l i a n c e
consolidate n o n - a t o m i z e d resin or gelcoat streams as they leave the tip of the nozzle. A large orifice eliminates
will be for the industry. At the same time, Reichhold's technical service peo-
plugging issues with filled resins or contamination. M a g n u m says the low-pressure sys-
"But 1 d o n ' t t h i n k a n y o n e is happy with the current generation of gelcoaters," says Sours. "Most of the current e q u i p m e n t is an a d a p t a t i o n of the flowtype application technology. We're working o n s o m e t h i n g conrpletely different."
ple are h e l p i n g customers evaluate process changes that can improve productivity a n d operating efficiency, as well as reduce exposures a n d emissions to c o m p l y with g o v e r n m e n t regulations. Other resin producers are also busy
tems offer the best emissions performance yet. Test data supplied by the company show substantially reduced emissions for resin a n d gel-coat w h e n compared to an airless/air assist chop
i n t r o d u c i n g new low-styrene products. At Composites 2000 in October, for example, AOC i n t r o d u c e d a new genera-
a n d gel-coating system. Venus Industries adds its own low pressure, internal mix systems for
Sours says his c o m p a n y is also selling more robotic e q u i p m e n t . The motivations for robots are productivity and c o n t r o l l i n g material use a n d thickness. "Robots are taking the h u m a n e l e m e n t out of production," notes Sours. "Robots do things consistently, and prod u c t i o n takes the same time every time."
tion of acrylic b o n d i n g resins that combine reduced styrene emissions with
e n h a n c e d e n v i r o n m e n t a l systems. The
Mel Saccomanno, engineering man-
c o m p a n y offers nozzles for traditional spray application as well as flow a n d i m p i n g e m e n t coating. Glas-Craft lnc, Indianapolis, Indiana, claims to have the next g e n e r a t i o n in n o n - a t o m i z i n g t e c h n o l o g y - the Delta V Force nozzle. The product is a single-orifice, directed-column nozzle for n o n atomized d i s p e n s i n g of resin. Testing at a major American university last year (May 2000) fotmd that the level of styrene emissions with impingem e n t - t y p e t e c h n o l o g y was 20% higher t h a n tests with the new Delta V Force nozzle from Glas-Craft.
ager for Aqua Glass in Adamsville, Tennessee, has first-hand experience w i t h the learning curve associated w i t h
higher t h r o u g h p u t s a n d the ability to increase filler loadings. Trademarked HyCryl C668 Series, the polyesters are engineered for spraying in open m o u l d processes.
New equipment The new word in open m o u l d i n g is 'applying' resin. The current trend is to move away from 'spraying.' Typical of the trend to n o n - a t o m i z e d dispensing of resin are the so-called flow coaters a n d i m p i n g e m e n t - t y p e nozzles. Flow-coat nozzles typically have a series of exit holes that produce a n o n atomized, linear c o l u m n of resin. While this m e t h o d reduces styrene emissions, early models were not good at dispersing glass fibre u n i f o r m l y in the laminate. h n p i n g e m e n t nozzles addressed that problem by having a wedge cut in the centre with two dispensing holes in the angles. The two c o h m m s of resin exiting the nozzle would intersect a n d develop a spray pattern. O n e of the leaders in i m p i n g e m e n t technology is M a g n u m Industries, Clearwater, Florida, which joined forces in a merger last September with Venus Industries, Kent, Washington. Subsidiaries of Graves Spray Supply lnc, M a g n u m a n d Venus c o n t i n u e to operate as u n i q u e entities for the short tern]. At the CFA show in October, Magnum featured its latest fluid i m p i n g e m e n t t e c h n o l o g y for resin a n d gel-coat. Frademarked FIT, the systems
20
REINFORCEDplastics January 2001
Styrene regulations elsewhere in Europe vary from country to country, but the trend is toward increasingly tight control standards. Lynn Sours, general manager, GS Manufacturing, says the state-of-the-art is good for resin a n d glass but still needs work for gel-coat application. "The guns for resin a n d glass are OK," says Sours. "There was a learning curve as the new guns put on too m u c h resin at first. Applicators had to adiust the glass application a n d get used to the feel of the new e q u i p m e n t . As a result, c o n v e n tional spray guns will soon be obsolete."
new materials and equit)ment. Speaking like an experienced politician t r y i n g to put the best face on a bad situation, he describes the experience of switching to new materials and processes as 'fairly difficult,' and 'a substantial challenge.' Some of the d i f f i c u l t y comes from team mates inside the company. "Our people had developed an expertise doing things a certain way," says Saccomanno. "Then we come along and ask t h e m to change. The old spray guns had a certain feel to them. There was some kickback they were accustomed to feeling. The new flow coaters feel more like a garden hose. That's n o t the same feel a n d they had to change their technique." W h e n the e q u i p m e n t was first changed, S a c c o m a n n o says p r o d u c t i v i t y w e n t d o w n . As his team mates b e c a m e more c o m f o r t a b l e with the n e w equipm e n t , p r o d u c t i v i t y w e n t back up to pretty m u c h what it was before the change. In Europe, the most stringent regulations for styrene are in Scandinavia, where 20 p p m has been the standard for several years. New factories built today must n o t exceed 10 ppm, and they cann o t be built w i t h i n 4S0 m of a residential area. Styrene regulations elsewhere in Europe vary from c o u n t r y to country, but the t r e n d is toward increasingly tight
Open moulders prepare for the future
Magnum's FIT technology uses the impingement of two fluid streams to form the pattern,
control standards. There is hope, especially a m o n g fabricators in countries with an already stringent standard, t h a t all counties in the European U n i o n will a d o p t the same s t a n d a r d a n d avoid having a n y c o u n t r y suffer a c o m p e t i t i v e disa d v a n t a g e for r e d u c i n g emissions. Given the tight standard in Scandinavia a n d p e n d i n g t o u g h e r regulations in o t h e r European countries, it s h o u l d be n o surprise to find t h a t fabricators are l o o k i n g m o r e at c l o s e d - m o u l d processes like v a c u u m bagging, resin transfer m o u l d i n g (RTM) a n d v a c u u m
22
REINFORCEDplastics January 2001
assisted RTM. But a m a j o r i t y still uses the spray-up process and is expected to cont i n u e to do so for the next several years due to the low cost a n d high speed of the spray-up process. O n e of the leaders d e v e l o p i n g a n d p r o d u c i n g low-styrene e q u i p m e n t is Aplicator System AB of Sweden. According to sales vice president ClasAke J o h a n s s o n , the c o m p a n y has m a d e a n u m b e r of design changes that reduce styrene emissions, l:or exalnple, its glass fibre c h o p p e r gun mixes resin a n d catalyst inside the gun to reduce fumes.
Aplicator r e d u c e d t h e a m o u n t of solvent n e e d e d for c l e a n i n g the gun by using a small m i x i n g t a n k a n d p l a c i n g it close to t h e h e a d of t h e spray gun to m i n i m i z e t h e l e n g t h of the t u b e from m i x i n g t a n k to spray nozzle. The gun also m i n i m i z e s the s o l v e n t n e e d e d for f l u s h i n g the system by i n t r o d u c i n g c o m p r e s s e d air. The restllting t u r b u lence accelerates t h e c l e a n i n g a c t i o n of t h e s o l v e n t a n d lessens t h e a m o u n t needed. "All of the new m a c h i n e s use very m i n o r quantities of acetone," says Johansson. A n o t h e r system p o p u l a r in Europe for r e d u c i n g styrene e m i s s i o n s in o p e n m o u l d i n g is the resin roller dispenser. The roller, l o o k i n g very m u c h like a p a i n t roller, e l i m i n a t e s t h e bucket a n d brush of h a n d lay-up by d i s p e n s i n g catalyzed resin directly into t h e m o u l d w i t h o u t spray or h a n d m i x i n g . The system ( s o m e w h e r e b e t w e e n s p r a y - u p a n d t h e closed m o u l d processes) has q u i c k l y b e c o m e a best seller in the industry. Wolfangel G m b H recently introd u c e d a new gel-coat spraying system that redtices the a m o u n t of solvent required for cleaning. "Changing colour is simply a m a t t e r of c h a n g i n g the connector," says Roll Wolfangel. "No solvents or o t h e r cleaning liquids are required, even w h e n c h a n g i n g from black to white. This saves precious w o r k i n g t i m e a n d keeps the use of e n v i r o n m e n t a l l y undesirable solvents to an absolute m i n i m u m . "
New processes There is no q u e s t i o n t h a t some o p e n m o u l d fabricators are also looking at closed m o u l d alternatives. The most p o p u l a r o p t i o n s seem to be the lessc o m p l e x variations of the injection a n d infusion m o u l d i n g processes, such as P,TM, VARTM a n d v a c u u m bagging, and also cold c o m p r e s s i o n m o u l d i n g . Virtual Engineered C o m p o s i t e (VEC) t e c h n o l o g y is certainly a n o t h e r m u c h talked-about alternative to open m o u l d i n g . (See the D e c e m b e r 2000 isstie
Open moulders prepore for the future
of Reinforced Plastics for details a b o u t how G e n m a r converted from o p e n m o u l d i n g to VEC t e c h n o l o g y for its Glastron a n d Larson brands of pleasure boats.) Premix Inc, North Kingsville, Ohio, a t h e r m o s e t m o u l d e r a n d producer of sheet m o u l d i n g c o m p o u n d s (SMC), is promoting its own low-pressure, low t e m p e r a t u r e SMC system to open m o u l d fabricators. The c o m p a n y sees the t e c h n o l o g y as a way to develop new customers a n d grow the market for SMC. Its patented OpTorr process can be used with p o l y m e r a n d other low-cost t o o l i n g alternatives at 100 psi a n d cure at 93°C. To p r o m o t e the process, Premix works with ()pen m o u l d fabricators to develop an e c o n o m i c analysis comparing existing p r o d u c t i o n with the OpTorr process. If the fabricator decides to change to OpTorr, Premix will work with t o o l i n g makers a n d others to deliver a t u r n k e y process. Soli Dastur, Owens C o m i n g leader for market d e v e l o p m e n t services in Asia Pacific, sees evidence of a shift from o p e n - to c l o s e d - m o u l d processes in Japan, primarily driven by c o n c e r n s a b o u t r e d u c i n g styrene fumes a n d emissions. Elsewhere in the region, Dastur sees o n l y slow m o v e m e n t to closedm o u l d processes a n d the drivers there are material c o n s i s t e n c y a n d p r o d u c t quality. "With low labour cost and low volu m e production, most fabricators are using h a n d lay-up," says l)astur. "A few fabricators - those m a k i n g bus bodies a n d coolhrg towers, for example - are using spray-up to achieve a better finish a n d make parts faster."
The debate continues Meanwtrile, i n d u s t r y associations like CFA a n d CP1A c o n t i n u e to work with n a t i o n a l a n d provincial officials o n future regulations. CPIA Director of Composites C o u n c i l Jerry 1)wyer, for example, is hard at work talking with provincial Ministries of Labour a b o u t tire feasibility of
24
REINFORCEDplastics
January 2001
more s t r i n g e n t regulations for styrene exposures inside composites factories. "For most fabricators, a 20 p p m s t a n d a r d is n o t achievable e c o n o m i c a l ly," says Dwyer. "Open m o u l d fabrication is n o t a high-tech business. Most fabricators d o n ' t have the f i n a n cial resources to achieve the lower standard." Dwyer says the open m o u l d process is the largest category of composites fabrication in Canada, a c c o u n t i n g for 65-70% of all composites production. That's why tire trend to a more stringent exposure level is CPlA's n u m b e r one focus at the nlonlent. "The lower exposure levels are a bigtime threat to the composites i n d u s t r y in Canada," says Dwyer. "It's the hot b u t t o n right now." Dwyer says the association is d o i n g two things. O n e is e d u c a t i n g Labour ministers a n d others a b o u t the safety of the c u r r e n t 50 p p m standard, tire second is s e n d i n g letters to fabricators letting t h e m k n o w w h a t is h a p p e n i n g . "Sometimes the fabricators d o n ' t even know about the situation," says Dwyer. "We encourage t h e m to write to local officials to let t h e m know the potential impact o n their business." The debate also c o n t i n u e s in the USA. "As the proposed regulations stand now, they pretty muctr dictate that we put in a n incinerator," says Saccomano. "We d o n ' t agree with that approach. We d o n ' t t h i n k that's a viable way to go economically, a n d we d o n ' t t h i n k it makes sense w h e n you look at the whole s i t u a t i o n from an e n v i r o n m e n t a l perspective." In addition to adding cost, S a c c o m a n o says i n c i n e r a t i o n creates a s i t u a t i o n that is worse t h a n the original problem. "Our styrene emissions are very low to begin with," he says, "and to m i n i m i z e exposure levels inside, our v e n t i l a t i o n system moves a lot of air t h r o u g h the plant. We will need to m o v e a lot of air t h r o u g h the flame a n d b u r n a lot of n a t u r a l gas to i n c i n e r a t e the small a m o u n t of
Employers may benefit from process changes W h i l e the need to reduce exposure levels a n d e m i s s i o n s is p r o m p t i n g m o s t open mould fabricators to
look at process changes, the changes m a y p r o d u c e a n a d d i t i o n a l benefit in helping employees.
them
hire
and
retain
"Customers tell m e t h e y have a p r o b l e m g e t t i n g people to work for t h e m , a n d t h e n k e e p i n g t h e m o n c e they are o n the payroll," says Ron Adams, sales representative for O w e n s Coming. "Chemical exposures are o n e of the reasons." "A c u s t o m e r r e c e n t l y asked us to c o m e i n to c o n s u l t with t h e m a n d make r e c o m m e n d a t i o n s . T h e y have experienced 100% t u r n o v e r (change i n p e r s o n n e l ) d u r i n g the past eight months. Adams says t h e e m p l o y m e n t issue is p r o m p t i n g s o m e fabricators to seriously c o n s i d e r c h a n g i n g to a closed m o u l d process t h a t is cleaner a n d requires fewer people. Styrene regulations may be the major driver p r o m p t i n g fabricators to look at alternatives to o p e n moulding, but p r o v i d i n g relief from the e m p l o y ment
headache
might
be a close
second.
styrene in that air. In essence, we will be t u r n i n g styrene emissions i n t o a m u c h larger v o l u m e of g r e e n h o u s e gas enrissions." To i n c i n e r a t e styrene efficiently, process engineers will w a n t to c o n c e n trate the chemical in the air. But to conrply with O c c u p a t i o n a l Safety a n d Health Act (OSHA) regulations for exposure inside the plant, those same engineers have spent years i m p r o v i n g ventilation a n d diffusing the styrene in the air. S a c c o m a n o says the i n d u s t r y will c o m p l y with whatever the final rule t u r n s out to be, b u t in the m e a n t i m e they will kee t) t r y i n g to get the regulators to c h a n g e their minds. •