TPi September 2015

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58 Tube Products International September 2015
Minimal floor-to-floor time
Of the two methods, machining with rotating tools is the
more challenging. With this in mind, Horn has developed a
new tool system that is able to face the pipe ends, perform
internal and external chamfering, create the conical thread
with peeling inserts and produce a finished thread with three
tool cartridges (featuring thread-cutting inserts) that are each
offset by 120° – all in one pass.
The thread pitch for API pipes of medium diameter – which
is the dominant market segment – is exactly 5.08mm per
turn. The inserts used for thread machining are structured
differently from follow-on tools and are precisely coordinated
to produce the required thread geometry. First of all, the first
tooth of the first insert makes contact, followed by the first
tooth of the second cutting edge, then the first tooth of the
third cutting edge, the second tooth of the first cutting edge,
the second tooth of the second cutting edge, and so on. The
technology supports up to five teeth per insert. This results in
optimum distribution of the cutting forces across the individual
teeth and inserts, so that none of them are overloaded. This
machining concept enables an extremely short floor-to-floor
time, but also places a great deal of importance on precision
and cost effectiveness at the same time.
Optimum production technology
The tools used in this compact tool solution feature effective
internal cooling to facilitate heat dissipation and chip removal.
Depending on the application, the coolant flows through,
under or over the cutting edge. There is a minimum coolant
pressure of 50 bar and the volume flow rate is 50 l/min.
The most effective part of the cooling concept is the way the
cooling lubricant can be supplied through the cutting edge.
The thread-cutting inserts from the S117 thread system (with a
thickness of up to 7mm) ensure optimum heat dissipation and
vibration reduction. Integrated chip breakers that are tailored
to the material being machined make for excellent chip
control. The threading insert is secured in a precision insert
seat that provides lateral support by means of an individual
and adequately dimensioned clamping bolt. There is no need
for any additional elements such as separate chip breakers,
supports, etc.
The substrates offer a combination of hardness and toughness
in accordance with the specific application. The AS66 PVD
multi-layer coating, which is highly resistant to wear, is used
on the inserts, and the surface parameters of the cutting
edges are optimised for the particular application. In terms of
their cutting edge geometries and position in the tool head, all
the inserts used in this complex tool system are designed to
ensure optimum cutting conditions and chip control.
Technology leader for oilfield
pipe threads
This technology from Horn for producing oilfield pipe threads
in a single machining pass offers major commercial benefits:
• Enhanced productivity
• Excellent surface quality
• Superb thread accuracy with secure positive and non-
positive locking
• Threaded surfaces with a high load-bearing ratio to prevent
galling due to high torques during disconnection and
connection processes
• High levels of leak tightness and concentricity
These complete tools can be used with an API diameter
range of 2 3/8" to 26" as standard. The Horn system also
supports pitches of up to 10mm/turn with diameters above
14", although this option is not currently available as part of
the standard solution.
In spring 2011, Horn received certification according to API
Q1 from the American Petroleum Institute (API). The API is the
largest association for the oil and gas industry, including the
petrochemical industry, in the USA. With this Q1 certification,
Horn was the first company worldwide to be included in the
APIQR’s Composite List for the development, manufacture
and sale of turning and milling tools. This achievement,
combined with the company’s ISO 9001 certification, is
positive proof of its commitment to compliance with higher,
internationally recognised quality standards.
Horn’s many years of experience in this segment, coupled
with its approach of offering the best solution to meet a
particular challenge, have enabled it to achieve its objective
and given it a competitive advantage. Horn is recognised
as a technology leader in various areas, and these now also
include the machining of oilfield pipe threads.
Paul Horn GmbH – Germany
Cartridge for thread chaser system 315