Gentle spinning: A game changer

All spinners would agree that they could
produce a better yarn if they can ensure good
fibre opening and cleaning while avoiding
fibre rupture. Yet, most preparatory lines
meet this objective only partially. The objective of this
paper is to present a case for how to achieve gentle
opening and good cleaning of fibres without rupture and
in doing so, what are the phenomenal benefits in the
process, cost and quality that can truly prove to be a
game changer for the spinning business.

The aim for any preparatory process should be to
retain the original properties of the fibres and yet achieve
good opening and cleaning. Reaching this target gets
more challenging as the speeds and production rates of
beaters and cards increase. However, no one will dispute
that if this target is met, there are a lot of fallout benefits
that result in the downstream process. We will discuss
here both how to achieve gentle opening and what
benefits it provides downstream.

Most spinners know that a majority of the process
problems encountered take birth at the preparatory stage
of blowroom and carding. Another way of stating this is
that the majority of the process problems can be resolved
if they are prevented at their inception when the
blowroom and carding operations are optimised.

While most users readily accept without debate that
pins provide gentle opening and prevent rupture whereas
saw tooth wire has a harsh opening action, many among
them prefer using saw tooth for multiple reasons. While
some believe pins are good for cotton and not synthetic
fibres, others believe vice versa.

Then there are those who claim pins are good for
trashy and recycled cotton fibres, while others believe the
opposite is true. Some believe wire is better for blends or
mélange, while others disagree. Further, some believe
pins are not effective for long staple fibres while some
think pins are more suitable for longer staple than
shorter! People also have the opinion that Pinned
Lickerins are suitable only for 3-Lickerin Cards and not for
Single Lickerin ones.

Many prefer using wire over pins purely from
operating convenience point of view. They believe that
wire costs less to replace, replacement in case of an
accident is easy and fast, it is easier to achieve process
parameters using wire than pins and their team is
comfortable maintaining wire clothed rollers rather than
pin rollers. Still others may choose to play safe and follow
the OEM recommendation or prefer to continue using
what came with the machine.

Lack of sufficient experience or awareness of how
pins work may be a reason for creating such
contradicting opinions regarding what pins can do and
what they cannot. Based on our experience at Basant
Fibertek and the numerous studies we have conducted in
various mills in India and abroad, we shall attempt to
address most of these issues in this article.

Before we go into the details of results of using pins
versus saw-tooth, let us first study how pins act on fibres
differently than saw tooth wire.

The above graph illustrates that pins, having a
smooth spherical tip provides a very gentle action on
the fibres as opposed to wire which has a knife-edge as
the acting portion. The pins help to disentangle the
fibres without rupture whereas the wire tends to rip
open the neps. This creates rupture as well as micro
dust. Further, wire tends to pulverise the trash, making
it more difficult to remove it from the fibres as opposed
to the pins that have a dedusting action on the fibres,
resulting in the trash being separated from the fibres
without getting broken into smaller particles.

Another major benefit of pins is that the rounded tip
wears out very slowly and a new tip keeps getting
formed as the original one wears out. The resultant
effect is that pins last 5-10 times that of wire, thus
ensuring more consistency in quality, besides
dramatically increasing life multifold.

At the outset, we can state that any fibre or any fibre
mix can be suitably acted on using pins provided the
pin pattern, angle, pin projection and pin density are
suitably designed according to the application and the
machine settings are optimised for best performance.
Just as one type of wire cannot give the optimum result
of all types of fibres, the same is true for pins also.

Having interacted with many competent technical
people in the industry over the past years, we can
emphatically state that only a few, after a scientifically
conducted trial on their particular fibre mix, have come
to a conclusion regarding whether wire or pins are
better suited for their requirement.Even in such cases, it
is debatable whether the correct pin pattern and
optimum settings were used for the trials or not. The
rest have come to this conclusion either based on
assumptions and presumptions or influenced by
another’s opinion.

Most of the leading spinning machinery
manufacturers are increasingly adopting gentle
spinning. They have redesigned their blowroom to
reduce the number of beating points for cotton as well
as synthetic fibres. They have also adopted, wholly or
partially, pinned beaters and pinned lickerins in place of
saw-tooth wire rollers. One can see many more
preparatory lines now using pinned rollers than 10
years ago and this trend is going to only increase as we
move into the future.

Gentle opening and cleaning of fibres ensures a high
quality, clean card sliver with lower content of short
fibres. This in turn significantly reduces the level of
comber noil, seed-coats sticking inside combers, the
level of ends down on the ring frame and winder cuts
This can have a huge overall impact on productivity,
quality, efficiency and cost reduction, all leading to a
dramatic boost in profitability. This is why we believe
that gentle opening is a game changer for the spinning
business.

Over the years, we have been successful in replacing
saw-tooth beaters with pin type in all types and makes
of beaters for all types of fibres, in India and abroad.
Similarly, many successful retrofits of Pinned Lickerins
are running in Single Lickerin Cards of all makes and
models for counts from 2s to 80s. We have successful
installations for virgin as well as recycled fibres, cotton
as well as synthetic fibres, grey as well as dyed fibres,
short as well as long staple.

If we do not have an existing installation for a
certain type of fibre mix or machine, we offer the client
a risk free trial with money back guarantee in case the
trial doesn’t meet the pre-agreed objectives. All we need
is a client willing to try something new with an open
mind and full commitment, which is a prerequisite for
any successful attempt at innovation and progress.

While wire is much cheaper than pins and pin rollers
take more time to repair than wire ones, the lifecycle
cost of pin rollers is far less than wire. We have detailed
study reports and calculations to demonstrate that pins
are much cheaper to use than wire in terms of cost per
tonne of production. If the savings resulting from long
life, consistent quality and the gentle opening action are
taken into consideration, the payback on the investment
on pin rollers comes to less than a year.

The risk of damage to pins is lower than for wire
because pins are optimally heat-treated to ensure that
they are resistant to bending or breaking easily. Pin
rollers can be repinned at less than half the cost of new.
Moreover, pin rollers do not require frequent cleaning.

We at Basant Fibertek are committed to serve and
guide our clients in spinning to create a new benchmark
for the global industry for quality, productivity and
profitability and claim their true place in the world. The
expertise we have acquired is largely through client
experience sharing and cooperation in studies. For us,
customer success is our success. We are ready to serve
as soon as our client is ready to explore growth through
continuous process improvement. As one customer once
rightly commented, “Competitiveness is like a treadmill.
You have to keep running to stay in the same place!”