NIST
GCR 04-863
Composites Manufacturing Technologies: Applications in Automotive, Petroleum,
and Civil Infrastructure Industries
Economic Study of a Cluster of ATP-Funded Projects
5. Additional Projects
in the Cluster Study
This section discusses
the technical challenges and accomplishments of two ATP-funded composites
manufacturing projects for civil infrastructure applications and one
composites manufacturing project for offshore oil and gas application.
Together with the two case studies, these three projects comprise the
cluster of five projects.
While the ATP-funded technical
tasks of these three projects have been successfully completed, there
has been less progress toward commercialization than for the two case
study projects.
INNOVATIVE MANUFACTURING
TECHNIQUES FOR LARGE COMPOSITE SHAPES:
Applications
in Load-Bearing Beams for Short-Span Bridges
Federal Highway
Administration studies indicate that nearly 30 percent of U.S. bridges
are obsolete or structurally deficient and that bridge maintenance
and repair are major ongoing expenses for many state and local transportation
departments. In addition, road construction in metropolitan and urban
areas significantly contributes to traffic congestion and to associated
economic and environmental costs (Taylor 2002).
Load-bearing composite
beams would be lighter than steel beams for bridge maintenance and repair,
easier to transport, and faster to install. Composite beams would also
be more durable and require less maintenance than steel. At the same
time, composite beams are currently more expensive and can be difficult
to fabricate into structures of appropriate shape and size, and with
adequate stiffness.
Strongwell Corporation,
working in conjunction with Georgia Institute of Technology, developed
a proposal for addressing the design, fabrication, and cost challenges
of composite beams for bridge maintenance and repair. In 1995, the ATP
agreed to cost share the project with an investment of $2 million. Strongwell
Corporation provided a cost share of $1.138 million. The project was
successfully completed in 1998.
Strongwell beams are made
with glass and carbon fibers bound in polymer resin. Fabrication uses
a pultrusion process that pulls fibers through a resin impregnation bath
and a shaping die to form complex cross-sectional shapes. Technical accomplishments
of the ATP-funded project include the following:
- Optimizing beam shape
and developing design standards to increase beam stiffness, eliminate
the need for braces, and reduce costs.
- Developing a manufacturing
process to create 36 inch by 18 inch double-web I-beams from vinyl
ester phenolic composites.
- Designing and fabricating
a dual reciprocating hydraulic puller system, synchronized by a programmable
linear controller, and developing a biofiltration process for emissions
control.
The ATP-funded technology
development effort led to a bridge demonstration project installed at
Sugar Grove, VA, jointly funded by Strongwell Corporation, the Federal
Highway Administration, and the Virginia Department of Transportation.
Future commercial use of the ATP-funded technology will lead to more
efficient bridge maintenance, faster completion of construction tasks,
and reduced congestion costs and environmental emissions. Realizing these
benefits will depend on achieving further manufacturing improvements
and cost reductions.
SYNCHRONOUS CNC MACHINING
OF PULTRUDED LINEALS:
Application
in Electric Transmission Towers
“While increasing
amounts of electricity are flowing over the nation’s ‘wires’,
America’s electric transmission infrastructure is aging. If new
technologies and more capital are not utilized to relieve congestion,
reliability will suffer. The economy will not grow, if it continues to
rely on an inadequate transmission system” (Silverstein 2002).
Modernization of the nation’s
electrical transmission system is inhibited, in part, by the traditional
use of steel structures. Steel towers are expensive to manufacture, require
large teams and heavy equipment to install, require anticorrosion treatments,
and can weigh too much for helicopter transport into remote areas. Using
lighterweight and corrosion-resistant transmission towers made from composite
materials could provide a number of benefits for modernizing the electric
transmission infrastructure, including the following:
- Improved ease of
transporting tower structures to remote sites (lighter weight).
- Faster installation
and lower installation costs.
- Improved maintainability
of corrosion-resistant transmission towers.
Ebert Composites Corporation
submitted a proposal to the ATP to address the design, fabrication, and
cost challenges of composite-based electric transmission towers. In 1994,
the ATP agreed to cost share the project with an investment of $1.032
million. Ebert Composites Corporation provided a cost share of $0.303
million. The project was successfully completed in 1997.
Ebert designed and demonstrated
an affordable manufacturing system, with significantly reduced production
times, for composite towers. The system combines the pultrusion process
with computer numerical control (CNC) machining. The ATP funding was
used to design a CNC workstation with a five-axis machining head that
performs intricate detailing on pultruded parts. Designs for different
parts could now be stored in the computer and produced with high accuracy
in any quantity and sequence without interrupting the pultrusion. The
CNC machine significantly reduced labor costs and human error. Southern
California Edison Co. (SCE) is currently testing several demonstration
towers that Ebert made using the ATP-funded manufacturing process.
INNOVATIVE JOINING AND
FITTING TECHNOLOGY FOR
COMPOSITE PIPING SYSTEMS:
Applications
in Offshore Oil and Gas Platforms
The weight of steel
piping for cooling water, process water, fire suppression, and chemical
systems on superstructures of floating oil and gas platforms is a
significant capital cost in offshore platform design.
To realize capital cost
savings, lighter-weight composite piping systems, able to reach operating
pressures of 400 psi, could replace “topside” steel piping
if cost-effective technologies were developed for joining composite pipes.
This requires the development of reliable composite-to-composite and
composite-to-metal joining technologies, to be produced with low-cost
manufacturing processes that replace labor-intensive practices.
Specialty Plastics, Inc.
makes composite pipes and components for the petrochemical and marine
industries. To enable and stimulate the use of composite piping on offshore
oil and gas platforms, the company proposed to develop an improved method
for joining composite pipe segments and to develop more efficient, less
costly processes for manufacturing pipe fittings. In 1995, ATP agreed
to cost share the proposed project with an investment of $1.809 million.
Specialty Plastics, Inc. provided a cost share of $0.773 million.
The project was completed
in 1998. While many technical objectives were achieved, the extent of
surface adhesion or chemical bonding between adhesives and composites
could not be improved sufficiently to reach a targeted 400 psi operating
pressure. As a result, the ATP-funded piping and fitting technology was
limited to seawater cooling systems and other lower-pressure applications.
In 1998 Specialty Plastics
was acquired by EDO Corporation. According to the manager of engineering
for EDO Specialty Plastics, the successor company will make the ATP-funded
technology available upon customer request. ATP-funded joining and fitting
elements have been incorporated in some commercial sales of composite
piping systems used for cooling water applications on offshore platform
superstructures, as well as in some commercial sales for onshore composite
piping systems. However, the successor company’s business strategy
and current plans do not include the active marketing of the composites
joining and fitting technology.
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of Contents or go to next section.
Date created: July 14,
2004
Last updated:
August 3, 2005
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