Page 33 - February-March-2017
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The TWIN draw frame TD 9T has a compact design, with only one operator platform in the middle

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 Few machines in a modern spinning                                                                                                                                                             cleaned. This, along with the high quality of each and
 mill are as critical as the roving frame.                                                                                                                                                     every component, entails the perfect control of fibers
 Corporate Highlights
 Building a solid and reliable roving                                                                                                                                                          during draft and top quality of the roving.
 frame is not an easy task and yet
 again it is absolutely necessary for the                                                                                                                                                      False twist area
 spinner as this machine can feed,                                                                                                                                                             As bobbins on modern roving frames are arranged in
 depending on the count being                                                                                                                                                                  two rows, rovings can have different angles at the
 produced, thousands of spindles at                                                                                                                                                            delivery of the drafting system and at the entrance of
 the spinning frames.                                                                                                                                                                          the flyers’ top. It has been argued that these different
                                                                                                                                                                                               angles can entail differences in the spinning triangle
 Marzoli, the only European                                                                                                                                                                    at draft delivery and different tensions of the rovings
 manufacturer of the full line of                                                                                                                                                              thereby causing an uneven take up of twist and
 machines for spinning of short staple                                                                                                                                                         variations in roving count.
 fibers with over 150 roving frames
 being sold every year worldwide, is                                                                                                                                                           On Marzoli machines all rovings lay parallel to one   stems from the amortization of the cost of the head
 the ideal referent for whoever wants to                                                                                                                                                       another: they have the same angle at the delivery of   and rear stocks on a higher number of spindles per
 choose the best technology. Its FT6E                                                                                                                                                          the drafting system and at the flyers’ entrance for   machine. However, the higher the number of
 and FT7E represent a state-of-the-art                                                                                                                                                         both the front row and the back row of bobbins.   spindles, the smaller the benefit stemming from a
 solution, yielding the best results for                                                                                                                                                                                                         further increase in machine’s length.
 efficiency, reliability and quality. The                                                                                                                                                      Individual sensors ensure that each and every roving
 article aims at presenting from a                                                                                                                                                             break is properly detected and the machine securely   Machines exceeding a certain number of spindles
 technical and technological point of                                                                                                                                                          stopped, even in case of roving overlap around the   also entail higher costs for electronics and
 view these machines.                                                                                                                                                                          cylinder/top roller. On the other hand, if dust passed   drafting drive.
 FT6E and FT7E  Drive system   where motion is transmitted through toothed belts. In                                                                                                           in front of the sensors the machine would not stop, it   Last but not least a higher number of spindles per

                                                                                                                                                                                               would continue to run. Individual sensors also make
             traditional machines spindles are moved by one


                                                                                                                                                                                                                                                 machine causes a reduction in efficiency.  The FT6E
                                                                                                                                                                                               suction not required. This, along with the IE3 motors
             motor which, through a long shaft, transmits motion


  leading-edge  to bevel gears which drive pulleys that drive belts                                                                                                                            and an overall design meant to minimize energy    (110mm gauge) can reach 224 spindles and
                                                                                                                                                                                               consumption, allows to save up to 4 Kwh.
                                                                                                                                                                                                                                                 produce bobbins of 16” x 6”. The FT7E (130mm
             which ultimately make spindles rotate. A group drive


                                                                                                                                                                                                                                                 gauge) has a spindlage up to 168 spindles and can
             allows to substantially simplify this transmission
                                                                                                                                                                                                                                                 produce packages of 16” x 7”. These numbers
             system. The drive comprises several motors, each


 roving frame  one driving a limited number of spindles. Each motor,                                                                                                                                                                             represent the limit in terms of number of spindles and
                                                                                                                                                                                                                                                 dimensions of bobbins to maintain top efficiency
             through a pulley, drives toothed belts which transmit


                                                                                                                                                                                                                                                 standards. A higher number of spindles per machine
             motion directly to the spindles. Shafts, gear boxes


                                                                                                                                                                                                                                                 would not give an additional benefit to the spinner as
 technology  and bevel gears are eliminated. Therefore it is                                                                                                                                                                                     the decrease in machine efficiency would not be
             possible to:


                                                                                                                                                                                                                                                 counterbalanced by the reduction in the average cost
             - reduce maintenance costs: fewer transmission


                                                                                                                                                                                                                                                 per spindle.
             components are needed and lubrication is no longer
             required;                                                                                                                                                                         Roving tension is kept constant within a pre-set

             - reduce noise;                                                                                                                                                                   range through sensors that constantly monitor     The flyers installed on Marzoli’s roving frames are
             - reduce vibrations: lower mechanical transmission                                                                                                                                roving’s fluctuations between the delivery of the   made of ultra-light alloy and are dynamically
             entails lower wear of transmission components and                                                                                                                                 drafting system and the flyer’s top and adjust the   balanced so that even when working at high speeds,
             therefore lower vibrations. This enables the machine                                                                                                                              speed of the spindles accordingly. These sensors   vibrations are kept to a minimum. Marzoli’s roving
             to work at higher speeds;                                                                                                                                                         play an important role in ensuring that there are no   frames can reach up to 1,500 rpm mechanically and
             - increase transmission efficiency: transmission                                                                                                                                  false drafts in the roving and that roving breaks are   the roving can be wound on standard tubes, with a
             system comprises only a pulley and toothed belts: no   27mm can be used to reduce the gauge between                                                                               kept to a minimum.                                diameter of 53.5 mm, or on thinner tubes , with a
 The FT6E and FT7E are driven by   shafts, no bevel gears are included. This allows to   nipping points. This guarantees a better control of                                                                                                     diameter of 48mm, to have a further slight increase in
 independent drives for the drafting   reduce energy consumption.   short fibers during draft.                                                                                                 Winding area                                      bobbin capacity.
 system, the flyers, the spindles and                                                                                                                                                          It is argued that to increase productivity and lower
 the bobbin rail. Every drive is   Drafting system            Marzoli drafting system can also rely on highly                                                                                  investment costs, spindlage and dimension of      The creel
 coordinated by the central CPU which   Marzoli roving frames can be equipped with a   efficient cleaners for both top rollers and bottom                                                      bobbins should be increased. This is only partially   The creel is equipped with hexagonal aluminum
 ensures perfect synchronization of all   3-over-3 or 4-over-4 top-of-the-class drafting system.   drafting cylinders. For top rollers there are two                                           true: a higher number of spindles per machine     rollers to prevent false drafts, a very important aspect
 the movements involved in bobbin   There are two options for the cylinder diameters: the   options: rollers with rubber fins and revolving felt                                               reduces the cost of the investment as the total   especially when working with combed slivers. Optic
 formation.   standard solution has a diameter of 32mm; however,   belts. For the bottom cylinders there are rubber                                                                            required number of spindles can be reached with   sensors positioned between the rollers ensure that in

             in case there is a high percentage of short fibers in   scrapers. These solutions guarantee that at every                                                                         fewer machines. From a unit cost (cost per spindle)   case of sliver break the machine is immediately
 The spindles drive is a group drive   the processed material, cylinders with a diameter of   turn both top rollers and bottom cylinders are always                                            point of view, there is an economic advantage that   stopped. Marzoli roving frames can be fed with cans
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