Page 39 - MMI-SeptOct2021 SM upload

If this is done incorrectly then research by Euromonitor Inter- they buy by 50 percent. When
layers of the composite materi- national, around 50 percent of Sandvik Coromant supplies a
al peel away from where they companies plan to reshape their drill to its customers, it must be
belong. This is known as de- digital strategies. One-third of re- able to guarantee that the drill
lamination which, according to spondents in Euromonitor’s Voice will last for a predictable num-
Sandvik Coromant’s customers, of the Industry survey 2020 said ber of minutes, whatever the cir-
is the most limiting factor in they will accelerate investments cumstances — every time!
their production. into automation tools — so, those
Delamination affects hole quality holes need to be made correctly in Better by design
and repeatability, the quality and unmanned lights-out scenarios. That’s why Sandvik Coromant
integrity of the final product and Therefore, manufacturers need developed its CoroDrill 863-O
®
manufacturers’ profits. Integrity to keep rethinking how they go high-performance drill for com-
tops it all because better hole qual- about drilling composites. posites, including carbon fiber
ity is vital for preventing compo- reinforced (CFRP) and glass fiber
nent failure and is very much de- Predictable wear reinforced (GFRP) materials. The
termined by the manufacturing It is established that hole surface drill has been designed with a fo-
processes that are used for ma- integrity is a real concern for cus on industries that make wide
chining or finishing the holes. aerospace manufacturers. But, use of composite materials and de-
The amount of heat generated what role can tools play in ad- mand more feet of material drilled
during composite machining also dressing these concerns — and per tool — like the Aerospace in-
becomes significant. The materi- how can a better drill benefit an dustry, which uses composite ma-
al’s poor heat conduction and the automation strategy? terials for manufacturing aircraft Machining
absence of chips pose risk to the First, let’s look at the ideal that frames and other parts. composite
resin that holds the material’s fi- manufacturers are striving for. To develop the CD863-O tool, the materials —
bers together. In other words, the They want holes that are of good O represents composite-only ap- that combine
machining of composites illumi- quality, consistent and repeat- plications, the first thing we did two or more
nates weakness in the machin- able. Of course, any tool will was apply it to the material in materials
with differ-
ing process that might otherwise wear out eventually, but this aerospace that is most prone to ent physical
be overlooked. wear must be consistent and pre- delamination. Specifically, unidi- and chemical
These weaknesses are empha- dictable from tool-to-tool. rectional laminate with no peel- properties
sized by the growing range, and The importance of predict- ply or woven back, which is most — involves
unpredictability, of composite able wear can’t be emphasized commonly used in aerospace cutting, or
fracturing,
materials available in the market. enough. Usually, a CNC will be wings and fuselage. We digitally of the fiber
This makes competitive machin- programmed to pull out the tool mapped the delamination to de- part of the
ing a challenge. at the point of failure. So, if the termine exactly how much de- material.
Why is this being mentioned now? lifecycle of the drill is not consis- lamination we experienced over
Well, hole quality is now arguably tent then, in a terrible-but-real- the life of the tools.
more important than ever in the istic scenario, one could cut the The computer system was set with
era of COVID-19. According to tool life of most of the products very tight tolerances, meaning the
amount of delamination we’d ac-
cept in any given hole. From the
resulting data, we could optimize
essential aspects of the drill’s de-
sign, like the angle of the helix —
or the spiral groove around the
drill. A higher helix benefits chip
evacuation, so can help reduce de-
lamination on the exit side. In con-
trast, too high a helix can separate
layers in the composite material
on the entry side. Either way, this
Source: Sandvik Coromant can result in layers or fibers over-
hanging the hole.
Other key features of the
Tools like the CoroDrill 863-O drill can help manufacturers fully automate their processes. CD863-O are its profile and grade.
Composite materials are not ho-
®

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