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Cast Polyamide 6 ("Nylon 6") as Sheave Material
Timco uses only the best virgin cast polyamide 6 with a polymerization
of 97% or better. This cast polyamide 6 or nylon 6 is cast in an open
or centrifugal mold. It is a very tough and resilient material. Even under
excessive loads, it rather bends before it breaks. If broken, the material
resembles a tear rather than the clean break one would find with steel.
Cast polyamide 6 is the ideal material for sheaves in most applications
where wire rope, wire, fiber rope, coated cable, fiber optical, flexible
hose, and belt must be lifted, flexed, and guided.
- Its lightweight is often the most important property of a nylon
6 sheave. It increases lifting capacity, reduces inertia and therefore,
cable wear, and it facilitates handling.
- The strength of a particular nylon 6 sheave can be calculated
precisely. Please consult our sheave design leaflet, or complete the
work sheet
for sheaves and let us do the calculations.
- The corrosion resistance of nylon 6 sheaves against saltwater
is well known. The material can be submerged in saltwater for decades.
- The service life of nylon 6 sheaves can be phenomenal. The
Groove wear is slow due to elasticity of the material.
- Design variations are easy because the material can be machined
at high tool speeds. Timco supplies sheaves with blank center bore,
with bushings (bronze or plastic) or anti friction bearings securely
mounted.
- Excessive loads can be handled by properly designed cast polyamide
sheaves. Timco uses press-fitted steel sleeves to achieve extra secure
bearing seating. Timco also supplies sheaves with firmly seated cast-in
metal sleeves where both torque loads and heavy lifting loads must be
handled.
- Price is an important consideration. Timco's manufacturing
plant is divided into two departments: One, where high-speed CNC lathes
literally "turn" out hundreds or thousands of sheaves, and a smaller
tool shop where even single sheaves and assembles can be made for a
fair and very competitive price.
The basic advantages of sheaves made of cast polyamide 6 by Timco are
as follows:
- Wire rope (cable): light weight, increases cable life, low
cost.
- Wire: low inertia, long service life, no damage to wire surface,
low cost.
- Fiber rope: low inertia, no snagging of fibers, low cost.
- Coated wire or cable: no damage to coating, low cost.
- Fiber optics: big sheaves radious economically feasible, no
damage to cable surface, low cost.
- Belt or similar: low friction, light weight, low cost.
The applicability of a nylon sheave is limited by high temperatures,
excessive speed, and by chemically aggressive environment. Please consult
out engineering department or request our engineering manual for cast
polyamide sheaves.
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