New extrusion technology significantly increases tape tenacity W&H subsidiary BSW MACHINERY changes woven fabric industry
BSW MACHINERY's well established tiraTex extrusion lines for highly oriented PP
tapes provide producers of woven PP bags with completely new opportunities. One
key element is the newly developed extruder series E105P for tiraTex. Its advanced
processing performance with very gentle yet tremendously efficient plasticising yields
so far unheard tape properties. The increased tape tenacity at high elasticity allows
producers to reduce the weight per bag, without sacrificing strength.
The tiraTex extruders for PP tape extrusion excel in the market since many years. They are
known for reliability and highest tape quality. Unique design features allow for fast start up
and reliable operation at very high output rates.
Film thicknesses of up to 300 micron or more require superior melt homogeneity at high output. That’s where the outstanding plasticising performance of the new E105P extruder series
comes into effect, delivering one precondition for tenacities well beyond values known from
other extrusion systems. The combination of advanced extruder with integrated melt pump
and intelligent cooling bath ensures a constant film thickness at very homogeneous temperature as a prerequisite for achieving the new tenacity values on the orientation downstream.
The new tiraTex extruder E105P further tremendously enhances the advantages for the PP
bag producer. The optionally available direct torque drives reduce the energy consumption of
the extruders by up to 5%. This goes along with a smaller footprint and lower noise emission
of the new series. Those savings are added to the huge potential which can be generated
through the new processing technology.
Higher tape strength increases profitability
Tape strength directly influences the weight of a woven PP bag to meet certain mechanical
bag requirements like impact resistance at bag drop. In a wide range of bags an increase of
strength can directly be transferred into a lighter bag. As the raw material dominates up to
80% of the cost of a bag every increase in strength can reduce the production cost for a converter.
While strength values of 3-4 g/den can be found in standard applications, high quality applications call for a minimum of 5-6 g/den. Elongation at break has to be maintained at or above
25%. This elasticity is needed for the quality bag to survive handling impact. Up to now higher strength values were compromising the elasticity or vice versa.
Now, the tiraTex processing technology has broken down this old barrier. Even with standard PP grades which are used commonly in the industry, tenacity values of 7 g/den and
higher can be achieved with elongation at break values ranging between 25% and 30%.
The processing characteristics are designed by the experts at BSW MACHINERY to provide
the best results even at highest outputs and production speeds of 500 m/min or more. This
adds a further benefits to this new technology as in the past output often had to be compromised for tape characteristics.
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Picture 01 (jpg): Tape production on tiraTex tape extrusion line
Picture 02 (jpg): Diagramme 'tape strength'
Website: www.bswtex.com
W&H-Group Website: www.wuh-group.com
Press contact at BSW MACHINERY: Mr. Hans Streimelweger
e-mail: hst@bswtex.com
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