Loom | Shuttle Loom | Shuttle less loom | Modern Loom | Classification of Modern Loom | Projectile Loom | Rapier Loom | Water Jet Loom | Air Jet Loom | Circular Looml

A loom is a device used to weave cloth. The basic purpose of any loom is to hold the warp threads under tension to facilitate the interweaving of the weft threads. The precise shape of the loom and its mechanics may vary, but the basic function is the same.

Shuttle Loom: The shuttle loom is the oldest type of weaving loom which uses a shuttle which contains a bobbin of filling yarn that appears through a hole situated in the side. The shuttle is batted across the loom and during this process, it leaves a trail of the filling at the rate of about 110 to 225 picks per minute (ppm). Although very effective and versatile, the shuttle looms are slow and noisy. Also the shuttle sometimes leads to abrasion on the warp yarns and at other times causes thread breaks. As a result the machine has to be stopped for tying the broken yarns.

Classification of Modern Loom:

Shuttle less loom: Many kinds of shuttle less looms are used for weaving such as Projectile Looms; Rapier Looms; Water Jet Looms; and Air Jet Looms.

Projectile Loom: It is sometimes called missile loom as the picking action is done by a series of small bullet like projectiles which hold the weft yarn and carry it through the shed and then return empty. All the filling yarns are inserted from the same side of the loom. A special tucking device holds the ends of the wefts in place at the edge of the cloth to form the selvage. This loom needs smooth, uniform yarn which is properly sized in order to reduce friction. Projectile loom can produce up to 300 ppm and is less noisier then the shuttle loom.

Rapier Loom: Rapier loom comes in many types. Early models of it use one long rapier device that travels along the width of the loom to carry the weft from one side to the other. Another type of rapier loom has two rapiers, one on each side of the loom. They may be rigid, flexible or telescopic. One rapier feeds the weft halfway through the sheds of warp yarns to the arm on the other side, which reaches in and carries it across the rest of the way. Rapier looms are very efficient and their speed ranges from 200 to 260 ppm. These looms can manufacture a variety of fabrics ranging from muslin fabric to drapery fabrics and even upholstery fabrics.

Water Jet Loom: In it, a pre measured length of weft yarn is carried across the loom by a jet of water. These looms are very fast with speeds up to 600 ppm and very low noise. Also they don't place much tension on the filling yarn. As the pick is tension less, very high quality of warp yarns are needed for efficient operation. Also, only yarns that are not readily absorbent can be used to make fabrics on water jet looms such as filament yarn of acetate, nylon, polyester, and glass. However, it can produce very high quality fabrics having great appearance and feel.

Air Jet Looms: In the air jet weaving looms, a jet of air is used to propel the weft yarn through the shed at speeds of up to 600 ppm. Uniform weft yarns are needed to make fabrics on this loom. Also heavier yarns are suitable for air jet looms as the lighter fabrics are very difficult to control through shed. However, too heavy yarns also can't be carried across the loom by air jet. In spite of these limitations, air jet loom can produce a wide variety of fabrics.

Circular Looms: These looms are particularly used for making tubular fabrics rather than flat fabrics. A shuttle device in it circulates the weft in a shed formed around the machine. A circular loom is primarily used for bagging material.

Historical Development of Loom | Chronological Development of Loom

A machine for weaving fabric by interlacing a series of vertical, parallel threads (the warp) with a series of horizontal, parallel threads (the filling). The warp yarns from a beam pass through the heddles and reed, and the filling is shot through the “shed” of warp threads by means of a shuttle or other device and

is settled in place by the reed and lay. The woven fabric is then wound on a cloth beam.

The primary distinction between different types of looms is the manner of filling insertion . The principal elements of any type of loom are the shedding, picking, and beating-up devices. In shedding, a path is formed for the filling by raising some warp threads while others are left down. Picking consists essentially of projecting the filling yarn from one side of the loom to the other. Beating-up forces the pick, that has just been left in the shed, up to the fell of the fabric. This is accomplished by the reed, which is brought forward with some force by the lay.

Chronological development of loom        

Yarn Tensioners | Types of Tensioning Device | Important Effects of Tensioning Device

Yarn Tensioners are devices by the help of which tension is given to the yarn. This is an important device because it enables us to provide necessary tension to the yarn as it moves through the different parts of the mschine.

Types of tensioning device 

There are basically three types of method by which tension is applied to yarn. They are as follows

• Capstan method 
• Additive method 
• Combined method

Capstan Method

This is the simplest form of yarn tensioning device where the yarn is passed around posts where the tension on the yarn is provided from the friction between the posts and yarns.

This follows the classic law of

Output tension = Input tension x eµθ

Additive method

In this method the yarn is passed through the middle of two surfaces in contact. The force is applied from above to give suitable tension to the yarn.

Combined method

The combined system is a combination of capstan and additive method. This device is a complicated system which on allows the addition of tension. We cannot decrease the tension with this device. It is seldom used.

Important effects of tensioning device 

If the tension is too high then

• The yarn can be damaged 
• The rate of yarn breakage will be high 
• The elongation property of yarn will change

If the tension is too low then

• It can lead to unstable or loose package formation which will cause problems during unwinding

Variation in yarn in different parts of a wound package will cause undesirable effects

For man made filament yarn improper tension will cause

• Change in molecular structure 
• Variation in colour shades

For staple or spun yarn too high tension will cause

• Yarn breakage at thin places

Factors influencing the selection of Tensioners 

• The device must be reliable to control uniform tension 
• The device must be easily thread able 
• It must not introduce or magnify tension variation 
• It must not introduce variation in twist 
• It must not be affected by wear 
• It must be easily adjustable 
• It must not be affected by oil and dirt 
• It must not encourage dirt collection 
• It must be easily cleanable 
• The operating surface must be smooth 
• It must be cheap

Winding Process | Precision Winding | Non Precision Winding

Winding is the process of transferring yarn or thread from one type of package to another to facilitate subsequent processing. The rehandling of yarn is an integral part of the fiber and textile industries. Not only must the package and the yarn itself be suitable for processing on thenext machine in the production process,

but also other factors such as packing cases, pressure due to windingtension, etc., must be considered. Basically, there are two types of winding machines: precision winders and drum winders. Precision widers, used primarily for filament yarn, have a traverse driven by acam that is synchronized with the spindle and produce packages with a diamond-patterned wind. Drum winders are used principally for spun yarns; the package is driven by frictional contact between the surface of the package and the drum.

Types of Winding

A.Precision Winding

B.Non Precision Winding 

A.Precision Winding 

By precision winding successive coils of yarn are laid close together in a parallel or near parallel manner. By this process it is possible to produce very dense package with maximum amount of yarn stored in a given volume.

Features 

• Package are wound with a reciprocating traverse 
• Patterning and rubbing causes damage of packages 
• Package contains more yarn 
• Package is less stable 
• The package is hard and compact 
• The package is dense 
• Rate of unwinding of package is low and the process of unwinding is hard 
• The unwound coil is arranged in a parallel or near parallel manner

B.Non Precision Winding 

By this type of winding the package is formed by a single thread which is laid on the package at appreciable helix angle so that the layers cross one another and give stability to the package. The packages formed by this type of winding are less dense but is more stable.

Features

• Only one coil is used to make this packages 
• Cross winding technique is used 
• The package density is low 
• Minimum number of yarn is wound 
• The package formed is soft and less compact 
• The stability is high 
• Flanges are not required 
• The rate of unwinding is high and the process is easy 
• The packages formed have low density

Geotextiles | Properties of Geotextiles | Applications of Geotextiles | Uses of Geotextiles

Geotextiles have been used for thousands of years. Geotextiles were used in roadway construction in the days of the Pharaohs to stabilise roadways and their edges. These early geotextiles were made of natural fibres, fabrics or vegetation mixed with soil to improve road quality, particularly when roadswere made on unstable soil. Only recently have geotextiles been used and evaluated for modern road construction. 

Geotextiles is defined as any permeable textile material that is used with foundation, soil, rock, earth, etc to increase stability and decrease wind and water erosion. A geotextile may be made of synthetic or natural fibers. In contrast, a geomembrane is a continuous membrane-type liner or barrier Geomembranes must have sufficiently low permeability to control migration of fluid in a constructed project, structure or system. A geotextile is designed to be permeable to allow the flow of fluids through it or in it, and a geomembrane is designed to restrict the fluid flow.

Geotextile use will sometimes mask slope failures until erosion is too far advanced to effectively and cheaply remediate the slope. When advanced erosion is detected it means costly restoration. In contrast when a hydroseeded area has crust failure, whether from weather, human or animal activity, the damage is visible early and can be cheaply repaired.

Erosion control covers a variety of conditions from high velocity stream flow to heavy wave action, to less severe conditions.; All conditions should be considered before selecting a method of control.

Natural fibre geotextiles degrade to form an organic mulch and help in quick establishment of vegetation. Different fibres will degrade at different rates eg coir geotextiles degrade in 2-3 years while jute degrades in 1-2 years. Coir is therefore useful in situations where vegetation will take longer to establish, and jute is useful in low rainfall areas because it absorbs more moisture.

In many arid and semi-arid areas the action of the wind causes considerable erosion. Geotextiles made from natural fibre such as coir, or jute can be used for wind erosion control, dust control, sand dune formation and stabilization. Jute is particularly useful for dust control because of the hairiness of the fibres.

The properties of polymer material are affected by its average molecular weight (MW ) and its statistical distribution. Increasing the average MW results in increasing:

• Tensile strength
• Elongation
• Impact strength
• Stress crack resistance
• Heat resistance

Narrowing the molecular weight distribution results in:

• Increased impact strength
• Decreased stress crack resistance
• Decreased processability

Increasing crystallinity results in:

• Increasing stiffness or hardness
• Increasing heat resistance
• Increasing tensile strength
• Increasing modulus
• Increasing chemical resistance
• Decreasing diffusive permeability
• Decreasing elongation or strain at failure
• Decreasing flexibility
• Decreasing impact strengthDecreasing stress crack resistance

Garments Accessories | Garments Trimmings | Lining | Marker | Interlining | Garment Pattern | Fabric Spreading

Garments Trimmings:
Those accessories which are used in sewing section are called trimmings.

Garments Accessories:
Fabric is the basic material in garment manufacturing. Except fabric, the other materials are known as accessories. For shirt making there are some accessories are commonly used.

Garment accessories:

• Thread 
• Zipper 
• Interlining 
• Button for example: Snap button  Plastic button. Metal button.
• Label:  Main label  Size Label  Wash care label
• Motif:  Leather  Plastic batch Metal
• Pocketing fabric 
• Lining 
• Velcro 
• Elastic 
• Cord 
• Ribbon 
• Toggles 
• Rivet 
• Collar bone.

There are some finishing accessories: 

Finishing accessories:

• Hang tag 
• Price tag 
• Plastic/ poly bag 
• Tissue paper 
• Carton 
• Scotch tape 
• PP belt 
• Tag pin 
• Plastic clip 
• Stiker 
• Butterfly 
• Collar insert 
• Back board 
• Necks insert

Button:

In clothing and fashion design, a button is a small disc, typically round, object usually attached to an article of clothing in order to secure an opening, or for ornamentation. Functional buttons work by slipping the button through a fabric or thread loop, or by sliding the button through a reinforced slit called a buttonhole.

Buttons may be manufactured from an extremely wide range of materials, including natural materials such as antler, bone, horn, ivory, shell, vegetable ivory, and wood; or synthetics such as celluloid, glass, metal, bakelite and plastic.

Hard plastic is by far the most common material for newly manufactured buttons; the other materials tend to occur only in premium apparel.

Zipper:

A zipper or zip fastener) is a popular device for temporarily joining two edges of fabric. It is used in clothing (e.g. jackets and jeans), luggage and other bags, sporting goods, camping gear (e.g., tents and sleeping bags), and other daily use items.

Interlining:

Interlining is a layer of flannel fabric sewn in between the face fabric and the standard lining. Interlining provides insulation and also adds a luxurious weight and softness, improves the drape of the fabric, and protects fragile fabrics. It is a popular choice with silk draperies.Depending on the application, interlining materials can be woven, knitted, or created by fusing fibers together. Silk, wool, and artificial fibers with good insulating qualities are common choices for interlining.

Garment Pattern:

The individual par of a garment which is shaped by hard paper is called pattern.

Working Pattern:
The patterns set which is used for sample making are called Working Pattern.

Marker:
Marker is a large thin paper which contains shape of required pattern pieces or a particular style of garments.

Fabric Spreading:

Spreading means smooth lying out of fabrics as per marker length and width.

Fabric Cutting:
Cutting is the process by which we can cut fabrics as per marker dimension with the help of knife.

Bespoke Garments:
Bespoke Garments are made on the basis of individual clients and according to the individual’s size and requirement.

Ready to Wear Garments: 
Ready to wear garments is made on the basis of target common groups, according to size charts, derived from statistical analysis.

Lining:
Lining is one kind of trimmings which is used underside of garments and use in next to skin.

Knit Stitch Formation Technique | Tuck stitch formation | Miss Stitch formation

The various steps of the stitch formation for the manufacturing of rib knitted cloth are shown inPicture 1.The following description refers to the work carried out by a single needle, however, thecarriage activates the needles of both needle-beds.


                                        
                                                                Picture 1 - The stitch formationA. The needles are in the knock-over position; the loop threads are inside the hook and thelatches are closed.

B. The carriage moves forward and the cam touches the needle butt. The forward motion of the cam with the tucking cam completely out, forces the needle to move upward; the thread inside the hook opens the latch. Once the needle has reached the tucking plane, the latch is completely open and the loop is laid on it.

C. The forward motion of the carriage makes the needle move upward again, since the loopingcam of the cam is completely out. The needle reaches the maximum height on the looping plane and the stitch is transferred from the open latch to the needle stem. This sudden motion can cause a backstroke, that is a reaction of the latch, which could accidentally close with a possible unsuccessful feeding of the new thread and a consequent knock-over failure. This would lead to the formation of a hole or the starting of a run in the fabric. In order to avoid this, the brushes ensure that the latch opens.

D. Once the maximum height has been reached, the needle is lowered, driven by the loweringcam; after reaching the tucking plane, the thread guide starts working, feeding the thread;the loop rises slightly on the stem and enters the space between the stem and the open latch.

E. The needle continues its downward stroke; the loop touches the latch and makes it rotateand close.

F. The needle reaches the bottom, i.e. the knock-over plane; the previous stitch, after closingcompletely the latch, knocks over on the new thread, forcing it to take up the typicalcurvilinear shape.

Tuck Stitch Formation
Two consecutive strokes of the carriage are necessary to form the tuck stitch (picture 2).

                                          
                                          Picture 2 – Tuck stitch formation
During the first stroke, the tucking cam of the cam is out and the looping cam is not working.Therefore the needle only raises as high as the tucking plane; the loop cannot slip on the stem,and therefore remains inside the hook after having completely opened the latch, in this wayallowing the yarn to be fed.During the second stroke both the tucking cam and the looping cam are activated; the needlerises up to the maximum height allowing the loop and the yarn to travel along the stem.Thereafter, the needle is fed with the thread for the second time; the loop and the first yarn closethe latch and knock over on the new yarn.The first yarn does not knock over as a knit stitch but takes a particular position, and fixes ontop of the previous knit stitch and at the bottom of the new one, creating a particular effect onthe fabric, called tuck stitch .

Miss Stitch Formation
High-butt and low-butt needles are also needed for the formation of the miss stitch (picture 3).  

                                             
                                                        Picture 3 – Miss Stitch formation
 The cam (with a half-way tucking cam and looping cam) meets with the needles: the high-butt needles rise while low-butt needles remain in a non-knitting position. During the downward stroke, the needles which have raised till their maximum height and have transferred the loops on the stem, are fed with a new thread. With the successive downward stroke the latches are closed and the loops is knocked over on the new thread.