Developments in Textile Continuous Processing Machineries
351
2 Continuous Processing Machineries
2.1 Inspection Machine
Once a grey fabric is received from weaving/knitting section, it is inspected on
inspection machines, which consists of light source and glass. Main aim is to confirm
the quality of fabric before wet processing is started. Usually, two different systems
are used to decide the quality of fabric known as four point and ten point. Any defects
from weaving or knitting can be identified and marked before the fabric is processed.
Inspected fabrics are classified based on number of defects found. The machine has
options to either batch or roll the fabric. Observed defects such as spots, knots etc.
are marked and the operation is called perching. In the next operation, known as
burling most of the imperfections are removed.
2.1.1 Recent Innovations
Recent innovation in inspection machine is use of laser beam to detect stains, holes,
thick and thin places and thread breaks etc. The system can be used in-line and it
helps reduce human interference ensuring consistent quality. Different instruments
are available which work on different principles such as coaxial, remission and
transmission technique. Scanner light beam is reflected to its source in coaxial method
while in remission method, the emitted light is received by a light guide system and
directed to a converter. In transmission system light can be received by a receiver
system located at the other side and it is used to detect the defects in the fabric.
2.2 Shearing and Cropping
Shearing is an operation where loose ends of fibres from the fabric surface are cut
using sharp edged razors. In processing of pile fabrics, cropping operation can be
used to control and adjust pile design and pile height. This can be used to reduce
pilling tendency of fabrics.
Figure 1 shows one of the earliest 4 cutter shearing machine (a) and line diagrams
of 2 cutter Fig. 1b and 4 cutter Fig. 1c machines. The earlier machines consists of
a strong frame carrying four revolving cutters fitted with left and right hand spiral
blades. A cutting point is a contact line between shearing cylinder and the ledger
blade, over which the fabric passes during operation. After completion of cropping,
the fabric is passed through revolving brushing rollers which removes the protruding
fibres which are cut during operation.
351
2 Continuous Processing Machineries
2.1 Inspection Machine
Once a grey fabric is received from weaving/knitting section, it is inspected on
inspection machines, which consists of light source and glass. Main aim is to confirm
the quality of fabric before wet processing is started. Usually, two different systems
are used to decide the quality of fabric known as four point and ten point. Any defects
from weaving or knitting can be identified and marked before the fabric is processed.
Inspected fabrics are classified based on number of defects found. The machine has
options to either batch or roll the fabric. Observed defects such as spots, knots etc.
are marked and the operation is called perching. In the next operation, known as
burling most of the imperfections are removed.
2.1.1 Recent Innovations
Recent innovation in inspection machine is use of laser beam to detect stains, holes,
thick and thin places and thread breaks etc. The system can be used in-line and it
helps reduce human interference ensuring consistent quality. Different instruments
are available which work on different principles such as coaxial, remission and
transmission technique. Scanner light beam is reflected to its source in coaxial method
while in remission method, the emitted light is received by a light guide system and
directed to a converter. In transmission system light can be received by a receiver
system located at the other side and it is used to detect the defects in the fabric.
2.2 Shearing and Cropping
Shearing is an operation where loose ends of fibres from the fabric surface are cut
using sharp edged razors. In processing of pile fabrics, cropping operation can be
used to control and adjust pile design and pile height. This can be used to reduce
pilling tendency of fabrics.
Figure 1 shows one of the earliest 4 cutter shearing machine (a) and line diagrams
of 2 cutter Fig. 1b and 4 cutter Fig. 1c machines. The earlier machines consists of
a strong frame carrying four revolving cutters fitted with left and right hand spiral
blades. A cutting point is a contact line between shearing cylinder and the ledger
blade, over which the fabric passes during operation. After completion of cropping,
the fabric is passed through revolving brushing rollers which removes the protruding
fibres which are cut during operation.