Manufacturing Machinery World August 2017

Going by recent product introductions, there
continues to be plenty of new cutting tools
developments aimed at helping machine
shops to produce deep holes. This can be
witnessed at Washingborough-based Destec
Engineering, for example, which is saving
time and money by using Titex XD deep-hole
drills from Walter GB. The drills are being
deployed to produce a series of 5 to 20mm
diameter holes (autoclave ports) to depths of
250mm in a range of materials including
carbon steel and super alloys. In one case –
producing holes of 5mm diameter by 240mm
deep – the solid carbide drills have reduced
cycle times by 7 hours and increased hole
quality.
Introduced two years ago by Destec, a
manufacturer of high-pressure containment
equipment and portable machine tools for
the oil and gas sector, the Titex drills have
not only cut production times from 30
minutes per hole down to just five minutes,
but eliminated the problems formerly
encountered with frequent tool breakage and
wander, as well as insufficient swarf
clearance.
“Ports are machined to high accuracy for
metal-to-metal sealing applications and are
integral features of autoclave hubs used to
join pipes with drilling heads,” explains
Destec’s machining supervisor John
Mullenger. “We produce a wide range of
hubs, up to 3ft in diameter, and in the past
would machine the holes – usually 2-5 holes
per hub – using a pecking sequence with HSS
drills. However, these drills did not have
through-coolant capability and were
constantly letting us down through wander
and breakages.”
Using Walter’s Titex XD drills, Destec
now successfully and consistently generates
the holes by first producing an initial pilot,
followed by a hole 12xD deep, then another
at 50xD.
It is clear that deep-hole drilling success
relies on innovation, and there are plenty of
recent developments attracting the attention
of production engineers, not just in the oil
and gas industry, but in sectors such as
aerospace and automotive.
For instance, the new Sumitomo Electric
Hardmetal SMD indexable-insert drill range
can now produce holes of from 12 to 42.5mm
diameter at depth-to-diameter ratios of up to
12:1, facilitating holes up to 300mm deep. In
addition, the range boasts detachable heads
that can be selected to suit machine type,
available power and the material being
processed, with the latter now seeing
structural steel and single-layer laminates
added to the list. Furthermore, this latest
version, says the company, brings new
orders of flexibility and tool inventory
reduction by enabling up to five sizes of drill
head to be used with a single drill body.
The complete Multi-Drill SMD
programme covers the SMDH replaceablehead
type drill holder, the MTL type drill
CUTTING TOOLS
TOOLING INNOVATION RUNS DEEP
head for high-efficiency drilling of general
steels, and the MEL version for soft steel,
grey cast iron, exotic metals and low-rigidity
set-ups, plus the MB for structural steel and
single-layer laminates.
Deep-hole series (8xD) and ultra-deep
hole series (12.1xD) are among those
available. Other features of the Multi-Drill
SMD range are reduced tool vibration and
noise generated under cutting conditions,
while optimised heat dissipation is achieved
via precisely positioned through-tool coolant
holes. A high-rigidity clamping system
ensures edge security and repeatable hole
size for the exchangeable drilling heads,
which are bolted to the body against fixed
precision-ground radial serrations.
There are two variants of drill head, one
with ultra-hard PVD (MTL ACX70) coating
and another with smooth PVD coating (MEL
ACX80).
Elsewhere, Floyd Automatic Tooling has
released the CrazyDrill SST-Inox from
Mikron Tool into the UK market. Two drills
are offered, to suit stainless steel and super
alloys, for drilling up to 8xD. Trials have
shown that 100 holes (0.5mm diameter, 8xD
depth) can be produced in stainless steel in
13 minutes. Cutting speed was 30m/min,
with 0.015mm/rev feed.
Deep-hole drills with very small
diameters are needed for various
applications in the automotive industry, such
as the drilling of fuel injection nozzles, and
for medical devices. In order to produce
these delicate parts, Mapal has extended its
portfolio of deep-hole drills with internal
cooling to include sizes from 1mm diameter.
The geometry of the new drills has been
specially adapted to the small diameters.
Thanks to the newly designed chip flute and
special face geometry, very high feeds and
cutting speeds are possible, says Mapal.
Furthermore, due to the cooling channels, the
drills are also suitable for use with minimum
quantity lubrication (MQL). Despite lengths
of up to 30xD, the gas/oil mixture is reliably
transported to the cutting edges.
Instead of a full coating, the new Mapal
tools are only coated at the head to make
them more cost-effective. The drills are
available in diameters from 1.0 to 2.9mm
(shank diameter 3mm) for universal drilling
in steel and cast iron, producing holes
between 20xD and 30xD.
A further innovation in this technology
segment comes from Big Kaiser. Available in
the UK from ITC, the new Big Kaiser SW
Smart Damper rough-boring head with a
built-in anti-vibration mechanism is said to
take precision hole-making to a new plateau.
Developed to improve productivity and
performance, the twin-cutting head makes it
easy to create deep bores in a range of
materials. The SW Smart Damper can operate
at cutting speeds of up to 200m/min in steel,
at a length of 8xD, without chattering, says
the company. This is four times faster than
the 50m/min maximum chatterless cutting
speed attainable without the SW Smart
Damper.
So what of gun-drilling tools? Well,
among the latest innovations here is the
Botek Lite-Cut series, which is available in
the UK from Mollart. Lite-Cut gun drills
incorporate a conical chipbreaker form and a
special nose grind that is said to require 30%
less power and enable higher penetration
rates, especially in more difficult materials.
In addition, by creating shorter, more
compact chip forms, swarf can be easily
evacuated from the hole using lower
pressure coolant.
Lite-Cut gun-drills are available in a
single-flute brazed tool, Type 110 and solid
carbide Type 113. Type 110’s brazed solidcarbide
tip is available in diameters between
1.85 and 51.2mm, while Type 113
incorporates a kidney-shaped coolant
channel with a diameter range of 1.5 to
12mm.
18 Machinery World, August 2017