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ISCAR is able to eliminate 40 seconds from cycle
times, which contributes directly to customer's
profitability. These conservative figures do not take
into account other advantageous factors such
as energy savings, set-up times, machine and
equipment amortization savings, etc.

Cylinder Blocks
Approximately 10-15 years ago, the most
commonly used cast iron cylinder blocks were
largely replaced by bi-metal blocks (aluminium
blocks with inserted cast iron liners). Today, more
and more car makers have replaced this method
with thermal spray processes (or CBC– Cylinder
Bore Coating), i.e. a special coating layer, which
is applied directly on aluminium cylinder walls.
There are a few different thermal spray methods:
PTWA (Plasma Transferred Wire Arc Spraying),
APS (Atmospheric Plasma Spray), TWA (Thermal
Wire Arc Spraying), etc. These coatings deliver
many advantages to engine/car performance, the
two most important being: Weight - engines are
much lighter without the presence of heavy cast
iron liners. Lubrication – friction between cylinders
and pistons is reduced due to the coatings’
microstructures.

A major manufacturing issue with the CBC coating
is that its hardness is relatively high and its thickness
is relatively uneven. Therefore, a cylinder honing
operation to achieve the final size can be a long
and complicated process. ISCAR's engineers have
targeted the honing cycle to enable these times to
be minimized.

They did so by first replacing a few time consuming
rough-honing stages with one very fast boring
operation. The tool is equipped with 4 to 6 ISCAR
PCBN inserts, which are individually adjusted to a
precise diameter.

PCBN enables operations to run at very fast
parameters. For example, for boring Ø100mm
cylinder we work at Vc=400-700 m/min and
f=1-1.2 mm/rev. In some cases, when the chip
evacuation becomes an issue, the PCBN insert is
designed with a dedicated chipformer on its top.

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