Composite Carabiners & the Dollar per Pound Ratio

A common goal for manufacturers of composites is to create and sell products that have the highest dollar per pound ratio possible. The higher the dollar per pound ratio is, the more margin the product will likely have. Lets look at some products/industry and examine their $/lb ratio.

At the low end, are commodity type composite products, typically made with e-glass and vinyl ester, are readily available, and have no significant variations between one manufacturer to the next. An example of this are common pultruded profiles such as I-beams, tubes, rods, etc. Obviously pricing will depend on quantity, but margins are very low and the dollar per pound sales prices can be in the $3/lb range...

At the other end of the spectrum are aerospace composites and recreational composite products. These products, often have a proprietary design, are carbon fiber epoxy, are specialty products, and often carry a brand name. The premium received is often due to the extra weight savings, durability, and extra labor involved in the product.

In recreational equipment, a constantly growing segment of composites and an early adapter of new materials and processes, the price per pound is often extremely high. Bicycles, golf shafts, tennis rackets, even ping pong paddles, all demand a premium. For example, take a surfboard that costs $500 dollars, and weighs 6lbs. The surfboard, constructed from polyurethane foam, woven 14oz e-glass, and vinyl ester resin retails for $83 a lb. (Most of this margin goes to manufacturing...)

One interesting recreational sporting product, not yet composite, is the carabiner used in rock climbing. As of now there is no composite counterpart, this study states that although a lighter weight carabiner would be desirable, it is currently not feasible. (I do not believe this is the case...)

This particular carabiner here, weighs 36 grams, and sells for $23 dollars. By my calculations, this is over $300 per pound for aluminum. A lightweight composite version could absolutely command a premium over this.

These are the type of products composite manufacturers are beginning to look at, niche markets with opportunity.

Photo Credit: Phil Hawksworth via Flicker

Composites Emissions... EPA Fines Composite Pultruder $151k

Not all composite materials are equal when it comes to emissions; different resins have different properties when it comes to VOCs. Additionally, the intensity of emissions varies from process to process, such that wet lay-up, pultrusion, compression molding, autoclave, etc, all have different environmental impacts.

One of the most common resins used in thermoset composites today, is vinyl ester resin. This resin has been long proven, is inexpensive, has excellent corrosion and chemical resistance, and is easy to work with. (long pot life, good vescosity, good shelf life). Unfortunatly, this resin has a moderate Volitile Organic Compound (VOC) content, as the resin is dispersed with a monomer, (most often styerne.) Styrene is known to have health effects, and in large quantities can harm air quality. In fact, the US EPA has described styrene as "a suspected carcinogen" and "a suspected toxin to the gastrointestinal, kidney, and respiratory systems, among others."

By switching to low or no VOC resins such as certain epoxies and polyurethanes, the health risks can be avoided. Although costs are often higher, and often the resins are not yet adapted to the manufacturing process. Additionally, the increased use of thermoplastic resins are also helping reduce volitile emmisions.

As well, the various manufacturing processes of composites variy the intensity of emissions. Wet or hand lay-up, where a laminate is cured open to the air, is far worse then a closed mold oporation. I am curious how the EPA takes this into consideration?

Recently, the EPA fined a Minnosta composites company, Conett Inc. (formally Geotek Inc.) $151,000 for violating "national emission standards for hazardous air pollutants by failing to reduce organic hazardous air pollutants from its pultrusion operations." The compliant can be read here.

As a compairson, here are two other EPA fines from 2003 and 2004, for the use of Styrene in hot tub manufacturing.

If you have any comments or insights, please share...

Photo credit: pfala vis flicker