Compact card - The future of carding
Universal carding unit for roller/
aerodynamic doffing
Click here to watch the compact card running
The HERGETH name is known for its long tradition of innovative solutions for the
nonwovens industry. In keeping with that tradition, the HERGETH carding unit offers many new
and unique advantages in efficiency, operation, web forming and maintenance.
The process starts with our new fine opening unit that allows the feeding to the card with very low air volume
and produces very finely opened fibres.

The
new High Precision Chute
(1) ensures a good
material feeding to the card. In the chute, the fibres are separated from
the air by progressively profiled blade bars
(2). This profile
reduces the risk of fibres intertwining around the bars and blocking
the system. The chute is made of segments that set the chute feed
depth by electronic linear units
(3). The fibres
leave the chute feed and are pressed to the feed roll by segmented
pneumatically loaded feed plates
(4). The pressure
can easily be set on a central valve to adjust to different blends.
This ensures good control of the fibres also on very wide cards. The
pivoting of the segments is measured to determine the fibre distribution. A PID
regulator controls the linear units that position the segments of
the chute to achieve a uniform weight across the width of the web.
The fibres enter the card through a large diameter feed roll with
unidirectional feed
(5). The feed table
(6)
is very large and strong. A large diameter of
the feed roll ensures better control of the fibres
entering the unit. The three main cylinders
(7) have the same
diameter. The use of three cylinders ensures that the
fibres are accelerated gently and carded from both sides. The carding is done by up to fifteen carding strips
(8),
producing a carding power that is similar to a conventional card
equipped with multiple rollers and strippers. The carding strips are
easily exchanged and are moderately priced. The carding strips can be
adapted to the material processed. The strips can be replaced with
blanks when less carding power is required.
A unique new feature is the H2 roller
(9). This
roller skims the surplus fibres from the first cylinder. The surplus
fibres are sucked off
(10), and reintroduced to the feeding machine thus
reducing the chances of thick spots and clouds.
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The carding feed and
carding unit are always the same for all applications. The
system is processing fibres from 10 - 100 mm length and
fibres from 0,9 dtex up to 100 dtex and coarse wool, and
bleached cotton.
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In order to optimize products different outlet configurations can be
fit to the machine at any time:
The LiRa (linear/ random) card combines the regularity of roller-doffed carding with
the random effect of aerodynamical carding to produce light weight
regular isotropic webs. Linear webs or heavy weight aerodynamic webs
are also possible within only a few minutes required to change over.
The design of the compact card had the future markets for
cards in
mind.
- extreme flexibility to produce a big variety of webs with
different fibres
- possible to produce multi-layer products
- short staple cotton and flushable fibres
Minimum space is required for a compact line for 3 fibres
with 2 roller-doffed and one airlaid layer: The standard in
hygienic products today. |

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A new way to produce 1:1 oriented webs is to use two
aerodynamically doffed carding units that are oriented in + 45°
and - 45° with respect to the main transport belt.
This method allows for the creation of a single web out of
two layers that are oriented at an angle of 90° with respect
to each other.
This unique process allows for the creation of new nonwoven
products. |
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A machine with
one cylinder and no carding elements, but with a stripping
roller, is used for coarse products. This machine, with
double-sided suction, can also form very heavy webs.
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Simple operation and low
maintenance were the main reasons for creating the new card. Spare
part costs are low since only two roll diameters are used. The rolls
may be easily
taken out, with the bearings on their shafts, to allow for rapid
product changeover or for quick servicing. All roll drives
are concentrated in a drive tower separate from the carding
unit. The rolls are directly driven with cardan shafts thus
avoiding belts, chains, and hidden motors in the machine.
The shafts are not affected by rotational loads avoiding
broken shafts.
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All motors are easily accessible. Feed, doffer, delivery rollers, and the stuffer rollers, if used, are all servo-driven. The three carding rolls and the stripping roller, if used, are frequency-controlled for quick speed changes.
All drives are SEW and the PLC is a Siemens S7 type.
The vertical arrangement of the card allows for easy access of rollers and carding elements. The setting of the rollers is done in only one direction and the setting of the carding elements can be controlled along the width of the carding cylinders. Air flow in the machine is top-down which reduces fibre accumulation. All carding cylinders and the feed roll are fully shrouded. Ample windows allow to view the cylinders even in applications with limited space.
No sub-frame is necessary as the machine is bolted to pillars. The card may easily be integrated into an existing production line.

- drive tower
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- cardan shaft
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