Graco Baby Uses Moldflow Plastics Insight to Meet Stringent Cost, Safety,
and Quality Issues
Laura Carrabine
Graco Children's Products is the leading juvenile products company in the
world. Located in Exton, PA, the company was established in 1942 and has
developed numerous products over the last 52 years including car seats,
strollers, high chairs, swings, cribs and bassinets, activity centers, and
other items.
Tom Lacey is a plastics engineer at Graco and is the primary Moldflow
analyst. The company uses Moldflow Plastics Insight (MPI) including MPI
Cool, Flow, and Warp modules. While his responsibilities vary from project
to project, most of the time, he is involved from the early stages of
development to assure that Graco parts are manufacturable in a reasonable
cycle time. In addition, he performs trouble shooting for problem parts.
Each of Graco’s products presents a very unique and difficult challenge
in both designing and manufacturing. Lacey says, "One of the largest
challenges is in developing car seats. We are tasked with designing a
plastic car seat that can withstand an incredible amount of force and stress
when it is involved in a crash. Once the seat is designed and all FEA and
crash testing has been performed, the task of implementing the program into
our domestic and Asian manufacturing takes place."
Graco Baby’s customers demand safety-driven, quality products that are
also cost-effective. Lacey adds, "By analyzing our plastic parts
throughout the entire design phase and with proper tool design, we are able
to create parts that are properly designed and manufactured in a reasonable
amount of time, which subsequently reduces part costs. More importantly
though, product quality and safety are the most critical issues to address.
When parents are asked what they expect out of our products, they almost
always say that they want their child to be safe at all times. Experienced
design teams and the use of MPI assure us that we are offering products that
meet all of the stringent regulations and tests imposed on them."
Graco Baby maintains several testing labs so all the requirements set
forth by the Juvenile Product Manufacturing Association and National Highway
Traffic and Safety Administration are adhered to before any products are
sold. The entire design and engineering team works together to make sure
they offer a product that is safe for all customers worldwide.
Lacey and his team use MPI for the analysis of all plastic parts. Other
engineers use Pro/E for CAD. Graco is evaluating the MPI 3D module at this
time. Meanwhile, Lacey uses MPI Cool, Flow, and Warp modules and works with
designers to discuss the structural requirements of each component.
"Structural analyses and engineering input tell me what areas of the
part are critical to product function. Comparing the MPI results with the
FEA data assures us that the product will perform flawlessly," Lacey
says.
Lacey adds, "Whether I am analyzing a part early in the design
phase, or an existing part in production, Moldflow gives me the ability to
predict the problems that will arise on the shop floor. The strength and
integrity of our products are extremely important, so we closely examine
where weld lines and air traps will form and also assure that the entire
part is properly packed out and cooled before ejection. The software gives
us the ability to foresee early in the design phase if there are going to be
any problems on the shop floor then we give suggestions on how to correct
them. It’s an enormous time saving tool. If we cannot locate problems
upfront in the design cycle, we pay a tremendous price once the tool goes
into production."
One of Graco Baby’s newest stroller projects was the first in which MPI
was used in-house throughout the entire design project. Lacey became
actively involved in the daily functions of the design team and interjected
plastics knowledge as the parts were initially being developed. "The
plastics engineering team imparted plastic input for the initial design of
the parts. Once we neared tooling issues I performed a molding window
analysis to obtain as close to an ideal process as possible. After running a
Flow analysis, I talked to our tooling engineer. We decided on an optimal
gate location by going through several iterations and possible sites. Using
Flow allowed us to see that the parts would fill properly, and that no thick
sections appeared which would hinder filling, packing, and cycle time of the
process. The software also allowed the team to check areas for strength and
cooling requirements."
With that information on hand, Lacey and his team revisited with the
project’s designers and relayed concerns and recommendations for
improvements. They were all focused on a properly designed part that was
easily manufacturable within a reasonable amount of time. From there, once
they were satisfied with parts form, fit, and function, they created a
preliminary cooling line system and performed a full Cool, Flow, and Warp to
obtain an idea of what the cycle time might be. If there were going to be
any concerns regarding warpage, it was addressed at that time.
"Many of the changes were made to the parts geometry to assure the
strength requirements were met while still being easily
manufacturable," notes Lacey. "I performed Flow analyses on
simpler parts, while more critical components required full Cool, Flow, and
Warp analyses.
"Once first shot parts were received, there were a few issues with
part warpage and flash. Additional analyses were performed to troubleshoot
and eventually remedy the problems. By getting our plastics engineering
group involved early in the design phase, we were able to assure that parts
were properly designed, gated in an area that would lead to a balanced fill,
and would be manufactured in a timely manner," says Lacey.
Graco Baby implemented MPI because it was spending a tremendous amount of
money using outsourced analysis agencies. "Since installing MPI, we
realized our return on investment within three months. I ran approximately
45 parts in the first six months of use," Lacey says. "As a direct
result of using MPI, we have significantly reduced the need for part changes
after tool issues due to filling or warpage problems resulting from poor
plastic part design. The cost of engineering changes due to part design
problems not identified during the design phase has been reduced by 67
percent."
Lacey learned to use Moldflow while obtaining his bachelor’s degree in
Plastics Engineering at Penn State Erie. Consequently, when he was hired at
Graco, he had a head start on using the software. He notes, "Working
with the program everyday here, improves my efficiency and knowledge of its
capabilities. You never stop learning when using Moldflow products."
Six months after starting work at Graco Baby, Lacey obtained Moldflow
Bronze certification in January 2004. Based on his training at Penn State,
he was able to take and pass the Bronze certification test in one day. Then,
in May of 2004, he attended the five-day training class for Moldflow Silver
certification. Subsequently, he took the three certification tests at his
leisure – fitting them in between work and free time – over a three
month period.
"As a Moldflow certified company, the notoriety gives us more
influence in transmitting and communicating our plastics analyses results.
It lets customers, suppliers, and manufacturers know that we are extremely
proficient at what we are doing."
Resource Center
Graco Baby is a subsidiary of Newell Rubbermaid Corporation.
Its manufacturing facilities are in Eleverson, PA; Macedonia, OH and Mainland
China. Its leading customers worldwide include Babies R’ Us, Wal-Mart, and
Target stores.
www.gracobaby.com
