Basics of Weaving and Types of Shuttleless Looms
For Apparel & Technical Fabrics, below mentioned weft insertion methods have been widely adopted around the globe:
Process of weaving fabric is not new to mankind but methods of inserting weft to form fabric keep evolving. We will discuss evolution of weaving, basics of weft insertion techniques and modern methods of weft insertion significantly. We will discuss following weft insertion system with their mechanism, advantages and limitations.
- Projectile Technology
- Rapier (Flexible & Rigid) Technology
- Water Jet Technology
- Air Jet Technology
- Multiphase Weaving Technology
- Multi Axial Weaving Technology
- Weaving Machines & Embroidery Unit
- Needle Weaving Technology for Narrow Fabrics & Ropes
- Three Dimensional (3 D) Weaving
The basic mechanism in any type of loom can be classified as mentioned below:
- Shedding : The Shedding opens the Warp sheet into layers to facilitate passage of weft.
- Picking: The Picking motion propels the weft from one end of the loom to the other.
- Beat Up: The beating motion lays the previously laid weft to the fell of the cloth.
- Take Up Motion : Take up motion is an arrangementto wind the cloth on to the cloth roller.
- Let Off Motion : The Let off motion is an arrangement to let the warp from the Weaver’s beam at uniform rate thus maintaining the appropriate warp tension throughout the Weaving process.
- Warp Stop Motion : The warp stop motion stops the loom in the event of warp breakage.
- Weft Stop Motion : The weft stop motion stops the loom in the event of weft breakage or exhaustion.
In modern looms,we are achieving better Efficiency with good productivity because provisions are given with Microprocessor based controls so weaving team can analyse following details in time and action prevents the losses at Grey stage.
- More Warp Breakages
- More Weft Breakages
- Stoppages due to Mechanical reasons
- Idle Stops in terms of Breakage per Hour
- Time taken by weaver to attend the loom
- Alarms for due Maintenance / Lubrication Schedule
- Production evaluation in terms of Loom Efficiency , Woven Meters , Picks Inserted , Total loom running hours etc.
- Control on piece length by alarming Signals.
- Graphical analysis to control cost of production , various defect occurrence during running loom , etc.
- Weave change is possible without any mechanical changes.
- RPM of loom can be changed without replacing Motor Pulley.
- PPI can be changed from Microprocessor.
- Less wear and tear as Reed Vibrations, loose parts may be recognized from loom display before break down.
MODERN LOOMS WITH DIFFERENT WEFT INSERTION SYSTEM:
1. Projectile Technology: SULZER WEAVING MACHINE
D 1 & D2 are the standard steel projectiles with small and large Grippers for the majority of commercial yarns . Recently Sultex introduced K 3 as synthetic (Carbon Composite ) projectile which has been used for economic production of very delicate fabrics.
The picking and the projectile units are separated from the moving sley. The Sley (Projectile track) carries the Reed and Gripper Guides . The gripper projectile, made of the fine steel 90 mm long , 14 mm wide and 6 mm thickness which carries the weft thread in to the warp shed. The weft is drawn directly from a large stationary cross wound package with or without accumulator. The gripper projectile is picked across the warp shed at the very high speed , the picking energy being derived from the energy stored in the metal torsion bar which is twisted at predetermined amount and released to give the projectile at high rate of acceleration. Picking always takes place from one side but several projectiles are working on conveyor chain located underneath the warp shed.
Sulzer is very versatile weaving machine and available in various widths. We can take more fabric splits together (Symmetrical or asymmetrical) to utilize full width.
2. Rapier (Flexible & Rigid) Technology :
In ATIRA INCUBATION CENTRE we have Dornier Rigid Rapier Looms for Technical Fabrics like Glass , Aramid , Carbon ( 3 K to 50 K ) Varieties. Warp preparation is being carried out on Karlmayer Sectional Warping and Texmer Direct Creel to Loom. We are developing prototypes of Leno Fabric , Glass Rovings, HDPE fabrics, PPGL Matrix, PP Filter Fabrics, Jute , Ceramic Insulation Fabrics etc in different weaves on Dornier Rigid Rapier looms. We are running three width of 300 Tex Glass Roving together to take advantage in production of wider width weaving machine.
CARBON FIBRE FABRIC
For Carbon fibre weaving , Direct Texmer“creel to loom” weaving takes place. Weaving of Carbon needs precautionary measures for human health, so team members are using the protective uniform with safety mask and eye covering glasses.
Team involved in Carbon Weaving
3K Carbon warp supply from Direct Creel
CARBON FIBRE SPECIFICATIONS:
|K No. of Fibres 1000 to 50,000|
3.Water Jet Weaving Technology:
Water jet looms were used in early 80 s for economic and bulk production of Polyester Sarees and Dress Materials, Shirting, etc. Mostly water jet looms were manufactured from Japan by the Companies Tsudakoma , Nisan etc. These looms are suitable for medium to fine Denier Polyester yarns while Cotton and Viscose weaving was not possible with commercial acceptance.
4. Air Jet Weaving Technology:
A successful weaving technology for medium to coarse cotton and spun yarns with the mechanism of air jet picking was introduced by Max Paboo of Sweden in 1958. A leno selvedge with a fringe of about 1/8 inch or 0.33 cm length is produced during weaving.These looms have been installed in large numbers due to high RPM and better productivity controls with the help of Microprocessor based controls.
Denim and Bottom Weights, PV dress Materials , Polyester Dress Materials , Cotton Shirting etc are easily maintaining an installed efficiency up to 90% with good quality of woven fabric in Weaving Mills of 200 to 400 Air Jet Looms capacity. Limiting Factor in air jet weaving is requirement of Skilled Weavers, Yarn Quality, Humid Conditions and loom Settings up to accuracy advised by machine suppliers. Control on leakages for compressed air makes bulk production with economic World Class Manufacturing.
5. Multiphase Weaving Technology:
Multiphase weaving machine is one in which several phases of the weaving cycle takes place at any instant such that several filling yarns can be inserted simultaneously. In this mechanism, more than one weaving shed is formed at a time. The Multiphase can weave 190 cm width with 69 meters of fabric per hour. Manufacturers of these weaving machines are Sultex, Switzerland and Techmashexport , Russia. Application of these fabrics is in Geo Textiles and Awnings.
6. Multi Axial Weaving Technology:
In recent years multi axial fabrics have begun to find favour in the construction of composite components. These fabrics consist of one or more layers of long fibres held in place by a secondary non-structural stitching thread. The main fibres can be any of the structural fibres available in any combination. The stitching thread is usually polyester due to its combination of appropriate fibre properties.
The most common forms of this type of fabric are shown in the following diagrams:
There are two basic ways of manufacturing multiaxial fabrics:
Weave & Stitch
With the ‘Weave & Stitch’ method the +45° and -45° layers can be made by weaving weft unidirectional and then skewing the fabric, on a special machine to 45°. A warp unidirectional or a weft unidirectional can also be used unskewed to make a 0° and 90° layer. If both 0° and 90° layers are present in a multi-layer stitched fabric then this can be provided by a conventional 0/90° woven fabric. Due to the fact that heavy rovings can be used to make each layer the weaving process is relatively fast, as is the subsequent stitching together of the layers via a simple stitching frame.
To make a quadraxial (four-layer: +45°, 0°, 90°, -45°) fabric by this method, a weft unidirectional would be woven and skewed in one direction to make the +45° layer, and in the other to make the -45° layer. The 0° and 90° layers would appear as a single woven fabric. These three elements would then be stitched together on a stitching frame to produce the final four-axis fabric. Machine manufacturers are Karlmayer, LIBA etc.
7. Weaving Machines & Embroidery Unit :
DORNIER MACHINERY has introduced recently a new dimension for pattern on Dornier Weaving Machines:
DORNIER A1: Air jet weaving machine with embroidery unit
DORNIER P1: Rapier weaving Machine with embroidery unit
The Dornier ORW (Open Reed Weave) technology allows wide diversity in pattern for clothing and decorative fabrics or specially applied reinforcements in technical textiles.
8.Needle Weaving Technology for Narrow Fabrics & Ropes:
Narrow looms technology is introduced by Jakob Muller, Switzerland.
Woven Ropes and Belts are better in Tensile Strength compared to conventional products.
Selection of the loom depends upon the type of textile material that has to be woven.
Furthermore, the versatility of the loom is an important factor so that the majority of the fabrics can be woven as per the ever-changing requirement and trend of the market.
Mostly the looms are equipped with microprocessor based controls. Analysing their data and taking timely actions will result in optimum productivity.
The performance of the modern looms is not deteriorated by its long term usage till its’ Scheduledmaintenance and lubrication is done properly.
I am grateful to Dr.A.K.Sharma , Director – ATIRA for giving me the opportunity to publish this paper. I extend my gratitude to the following leaders from the Institute and the Industry for their cooperation.
1) Mr. K K Misra (CEO,ATIRA)
2) Mr. Manoj R. Thakkar (Chairperson, IIMT STUDIES, AHMEDABAD)
3) Mr. R S Singh (CEO, BLUEBLENDS INDIA LTD.)
4) Mr. K L Jobanputra (CHAIRMAN, SOUTHERN RANGE, UGANDA)
5) Mr V.K. Maheshwari (Business Head , Mafatlal , Nadiad)
1) Weaving Mechanism Vol. 2 by Prof. N N Banerjee
2) World Class Manufacturing by KamalakarMutalik, Symbiosis, Pune
3) Indian Textiles 2015 by Jay Narayan Vyas
4) Handbook of weaving by SabitAdanur
5) Weaving: Machines, Mechanisms, Management by Talukdar and Ajgaonkar
This Article is provided by Mr Pradeep Kulshrestha and is also published at : http://www.fibre2fashion.com/industry-article/53/5235/basics-of-weaving-technology-and-modern-looms1.asp