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WEB & CORE TECHNOLOGIES INC. is a manufacturer of Core Shafts of steel , aluminum and carbon fibre composite.


The “BUZZ WORD” in the industry today seems to be CARBON FIBRE COMPOSITES, everyone has heard about them and the advertisements and salespeople are telling everyone that this is the SHAFT TO BUY.

CARBON FIBRE COMPOSITE is basically a reinforced PLASTIC SHAFT. Carbon fibres having very high “tensile” strength and bundled together and embedded in an epoxy plastic. This provides a shaft that has the “deflection resistance” of steel with the lightness of aluminum. Note we said “deflection resistance” not strength. Carbon fibre has high tensile strength which means that the fibres are hard to pull apart, however it is very brittle and cannot take much in the way of shock, such as being dropped or hit. Some shafts are “clad” or covered with metals to protect the carbon fibres. Since metals and plastics have vastly different expansion rates, the bond between the metal cladding and the plastic usually fails and the shaft looses strength. Fiberglass has been used as a cladding material since it is not as brittle, but it is not as “strong” therefore the space taken up by the “weaker” cladding adds weight but not strength. Composite shafts usually cost between 50% and 100% more than steel and aluminum. The deflection resistance depends on the full length fibres holding the plastic together, when holes or slots as machined into the body severing these fibres, this deflection resistance is reduced, and the advantage is lost.

When aluminum shafts can handle the load, aluminum is a better value. A shaft body of Carbon fibre and aluminum weigh about the same. The weights of the journals for either shafts will be the same, thus carbon fibre shafts will not weigh much less than aluminum. The carbon fibre shaft however is STIFFER meaning that it will not bend as easily as aluminum. However while an overloaded aluminum will bend, the carbon fibre will snap.

Aluminum shafts do not like to support a narrow roll on a wide shaft. This makes the shaft bend or deflect, and can cause the shaft to fail. Full width rolls support themselves and only rely on the shaft to hold them in place, so the shaft does not bend. When a roll is near the maximum width of the machine or shaft, there is very little bending strain on the shaft, so carbon fibre is of no advantage.

It should also be remembered that Carbon fibre composite shafts are subject to CATASTROPHIC FAILURE, this is a failure without warning. Aluminum and steel will bend before they break, carbon fibre will just let go.

In most cases where large narrow rolls and slits widths are to be used, it is advisable to use a steel body shaft and a shaft handler, using Carbon Fibre Composites only as a last resort. Shaft handlers can be very simple units and can be built by most maintenance shops, or purchased from material handling suppliers. When something better is required, WEBANCOR can design and build a shaft handler for the job.

WEBANCOR does not recommend the purchase of Carbon Fibre shafts until the proper research into the potential problems has been examined.