UK Promotes Composites Manufacturers
I ran across an interesting video demonstrating case studies of composite manufacturers in the United Kingdom. This video paints a very pretty picture of companies that use these materials to manufacture a wide range of items including: aerospace, bicycles, bridges, auto racing parts, etc.
This video has some great video footage of automated composite manufacturing using advanced composites materials. Automating these processes has long been a challenge and hurdle to using composite materials for commercial applications.
This video seems to be done by a UK government agency called the “Department of Business Innovation & Skills” promoting a national strategy for composites industry growth. It supposedly demonstrates companies working together to develop new composites technology.
Cirrus Composite Airframes
I found a very interesting Youtube peek inside of the Cirrus airplane assembly factory in Minnesota. While it would be cool to learn more about the actual composites fabrication of the individual parts, there is some great information about part bonding, inspection, and final assembly of the Cirrus aircraft. They use fiberglass and carbon fiber reinforcements to create a very strong and durable fuselage, and it is great to see in action.
Personal jets made of composite materials offer many advantages and unique properties. Design of complex shapes and anti corrosion of aluminum are two advantages. Disadvantages include repeatability and upgrading/modification.
Composites that are properly designed and fabricated can be used in many applications where safety is a big concern. Proper design and inspection during production can create an airplane that can be easily maintained and have a very long life.
Great factory tour courtesy of Aero-TV:
Underwater Pipe Repair
An epoxy and fiberglass wrap can repair steel pipes while submerged underwater. Repairing small holes in pipes by wrapping them is sure to be much less expensive and disruptive than replacing bad sections of pipe. Divers must have access to the whole circumference of the pipe and the pipe must be free of its contents to prevent contamination and allow for the wrap to seal the leak.
As always, surface preparation is very important, and is demonstrated in the video with the grinder. The epoxy must form a good bond with the substrate material, not the rust and scale that is on the outside of the pipe.
Jeff Longmoore of TFT demonstrates how this repair is performed in a Youtube video, but does so in a dry environment rather than the actual underwater one. Very interesting.
Panel Stiffness
Composites structures have requirements for stiffness to provide support and stability. Tests can be completed to identify the stiffness of a given area on a composites structure, i.e. how much it will bend for a given force.
The required stiffness of a section of a composites part depends upon the overall design and service expectations. Several factors, including the life expectancy of the object, the load rating of the composites surface, the inter-laminar bond strength, will help determine the threshold requirements. Testing is very important to determine the life expectancy of the part and whether it meets the requirements of its’ job.
Panel stiffness can be modified to meet these requirements using two basic methods. One way to increase the stiffness of an unsupported composites panel is to reduce the size of the panel through additional support structures. The other way is to increase the panel thickness across the same area. Choosing which method to use depends upon the engineering of the part and determining which method is acceptable with the surrounding part layout. If there is room to add supports, this is likely a quick and easy option. If there is room to increase the thickness, adding new or additional coring materials may be a simple solution.
Building a strong and stiff composites structure can be accomplished with the extremes of building a robust “skeleton” with small open areas and a thin skin, or having a basic, limited “skeleton” with a heavy duty cored laminate that supports itself.
A combination of the two usually works out best.
5 Axis Filament Winder
Filament winding is a process that can be used to create round fiberglass shapes with exceptional strength characteristics. Used for piping, tubing, and tanks, filament winding is normally an automated process that has computer-controlled equipment to place glass and resin around a mandrel- the piece that functions as the mold.
There are many variables that can be modified for filament winding, and these will affect the strength characteristics of the finished piece. The angle of the glass, number of passes (thickness), use of glass mat, and type of resin will affect the finished product strength characteristics.
I found a short video that demonstrates the equipment and the process.
As you can see, the glass is applied in a consistent manner across the part, allowing for uniform strength characteristics. As you can see, this is yet another process that the composites industry uses to create useful products with advantages over those of competitors.
Machining Composites CNC Video
Much like other materials can be machined, so can composites. Everything from basic fiberglass fabrications to advanced composites materials can be machined to add details and features.
This can be accomplished using hand-held tools guided by fixtures and measurements. Hand tools such as air routers, drills, and saws. A disadvantage is that the operator can commit errors and must be protected from safety hazards. These hazards include airborne dust, bending strain, lifting strain, and physical cuts.
For high volume or high precision applications, there are CNC routers that can be employed. These are fast, efficient, and safe. They may be expensive though.
Several manufacturers make CNC routers, and Thermwood is one as shown below.
This video shows several different applications and parts that can be routed with this large Computer Numerically Controlled machine.
Sponsor
