Ultrasonic Technology in Nonwoven and Textile Industry


Flexible technology for a flexible market

Today’s textile and nonwoven market is so complex that fields of application, production techniques and technologies for further processing as well as the variety of new products are difficult to grasp, even for specialists.The variety of new composite materials of fleece, paper, films and fabric as well as the numerous possibilities in terms of combinations have one requirement in common: a safe and reliable process.

Ultrasonics is also the method of choice for these materials, for example for parting fabrics so that there is no thickening of the material along the cut edges.

No consumables such as glue, staples or sewing thread are needed. The fabric remains intact, because no external thermal energy is directed into the fleece. Position, shape and displacement of the welding points can even support the desired properties of the composite.

Textiles is thus a field where ultrasonic technology can prove its uniqueness.

The Functioning Principle of Ultrasonic Welding

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Low frequency mains voltage is transformed into high frequency electrical energy. A converter connected in line converts these electrical oscillations into mechanical vibrations. This is done using a piezoelectric transducer having an efficiency above 95 %.

The mechanical vibrations are transferred to a transformer element coupied to the converter, the so-called booster. This booster optimises the amplitude for the horn.

The horn is individually manufactured for each application and transfers the ultrasonic energy to the material to be processed. To build up a mechanical clamping force, a so-called anvil is required enabling the energy to effect melting on account of physical processes (internal and external absorption).

The Optimum Process for any Application

Cycle-controlled process

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The actuator applies a defined pressure onto the anvil and hence onto the part to be welded between the two components. Usually, the ultrasonic irnpulse applied  simultaneously is time-controlled. Using the weld depth or the amount of energy applied as criteria for deactivation is also possible.

Main fields of application for cyclecontrolled welding:

  • Overlapping welding of belts and tapes
  • Linear welding of fabric and nonwoven
  • Welding textile materials with thermoplastic contents
  • Joining the end of a material strip to the start of a roll to prevent costintensive drawing in of material into the production equipment.

Seal and cut edges can also be manufactured to excellent quality. This only requires a special design of horn and anvil which is important for the following particular applications:

  • Cut belt strips to length and/or punching
  • Parting of edge binding for blankets
  • Manufacturing buttonholes and eyes applying a certain structure to the rim in order to leave the impression of a sewn edge
  • Parting colour ribbons in bureau machine industry

Continuous Process

Two or more overlapping material strips are fed between horn and anvil which, if required, is rotating. Again, different systern combinations are possible:

Fixed Horn/Rotating Anvil

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This is the most commonly applied combination. Material strips (e. 9. fleece for use in agriculture) are joined at very high speeds using special profile wheels. Using profile wheels, sandwich structures can be generated. Combinations of different materials such as paper, films and textiles are particularly interesting applications. This combination can also be used for cutting processes. This usually involves cutting without sealing or with only slight edge sealling. The extension of the service life as well as the reduction of the cutting force and hence an increased cutting speed are strong arguments for the application of ultrasonic technology. Non-thermoplastic materials can also be cut. In this case ultrasonic energy supports breaking of the materials. Maximum precision is of course a prerequisite in such applications.

Rotating Horn/Rotating Anvil

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In this combination horn and anvil serve both to weld and to transport the welded product. In most cases both horn and anvil are driven synchronously. As in this system only a limited amplitude can be generated. This method is usually used for thin materials having a low mass per unit area.

Fixed HornlFixed Anvil

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This combination is usually used for cutting/ parting applications with simultancous sealing. However, it can also be used for continuous welding of paper, films, or textiles.

 

 

 

Refrance: BRANSON BROUCHER

Moisture Management


  • By:- DR. PETRY, TEXTILE AUXILARIES

  • Definition

In general, „moisture management“ is understood to be the ability of a textile to absorb gaseous or liquid humidity from the skin, to transport it from the inside of a textile to the outer surface and to release it into the surrounding air.

To evalua;te the „moisture management“ of a textile one has to know about both the basic temperature regulation of the human body, and about the properties of the textile required by this regulation.

click to download :- MoistureManagement


Merchandising in Garmenting


Merchandise means goods bought and sold; and trading of goods. Merchandising is an activity of selling and promoting the goods.

Merchandiser is a person who interacts with the buyer and seller, and also puts efforts into proper relation between buying offices/ buying agents/ agency and seller/ exporter in terms of executing an order.

A garment export unit generally has many departments like stores, cutting, production, packing, checking etc. Merchandising department is the star of the department among all the working departments in the Export concern, because Merchandising is the only department having maximum control over the departments and total responsible for Profit and loss of the company.

The job of a merchandiser is to co-ordinate with the entire department in the office as well as the customers. Merchandiser meets the buyers and collects the details of their requirements etc., to develop the relationship with the customer.

Objects of Merchandising

Merchandising denotes all the planned activities to execute and dispatch the merchandise on time, taking into consideration of the 4 Rs to replenish the customer.

  • Right Quantity: To dispatch right quantity of product what buyer ordered.
  • Right Quality: It should be with right quality as accepted both parties.
  • Right Cost: Everybody wants more from what they are paid.
  • Right Time: No one wants to wait idle even in a Restaurant. Keeping delivery schedule is mandatory.
  • Planning Capability: Merchandiser should be capable of planning, based on the planning the order is to be followed. If the planning is not done properly it will directly affect the delivery time of the order.
  • Decision making: For a Merchandiser, decision making power is most important. He should think about the decision to be taken and to act in a right way.
  • Communication Skill: The communication is very much important to promote the business activity. The merchandiser should remember that communication must be lurid and should having face to face conversation with the buyer.
  • Loyalty: Loyalty is an essential character of human beings. Especially for the business people like merchandiser it is a must.
  • Knowledge about the field: Merchandiser should have adequate knowledge about the garments, Computer knowledge, and technical knowledge to communicate with different people in the business is a must.
  • Co-ordinate & Co-operate: Merchandiser is the person who is actually co-ordinate with the number of departments. To Co-ordinate with different people in the industry he should be co- operative.
  • Monitoring ability: Merchandiser should monitor to expedite the orders.
  • Other qualities: Education, Experience, Situational Management, Ability to Evaluate, Dedication, Knowledge of expediting procedures.

Function of Merchandisers

  1. Developing new samples, execute sample orders
  2. Costing
  3. Programming
  4. Raw materials / Accessories arrangement
  5. Production scheduling (or) route card drafting
  6. Approval of various Process, Pattern and size set
  7. Pre production follow up
  8. Meet Inspection Agencies
  9. Production controlling
  10. Identifying shortages and make arrangement for the shortages
  11. Following quality assurance procedures, quality control procedures
  12. Monitoring the in-house, sub-contractors and junior activities
  13. Buyer communication
  14. Communication with sub-contractors, processing units & other 3rd parties
  15. Proper reporting
  16. Highlighting to the management
  17. Record maintenance
  18. Developing samples
  19. Placement of orders to suppliers
  20. Taking measures for consistent production
  21. Taking preventive action to maintain the targeted performance in all areas of activities
  22. Attending meeting with superiors and furnishing the required details about merchandising

Technologies for the clothing industry


Synergies among makers of machinery, as well as systems and plants and the clothing industry aim both to the optimisation of the garment and to its suitability to be used according the customer’s demand.

As a consequence organisation of the production on one side, methods applied, machines, and component materials (from the fabric to the accessories) play a synergetic role which determines the product quality.

Organisation and information management, logistics, as well as specific hardware and software packages for CAD and CAM systems are representative of the high technological level offered by the Italian manufacturers

Receipt of goods

At their reception, all pieces must be immediately provided with a bar code with the following information: fabric variant, colour variant, real fabric width, total length, net length after detection of flaw lengths, entry date into the warehouse.

Today also the clothing manufacturing companies need to have a range of equipment for printing labels and bar codes. These printers through a serial or parallel port can be connected to any system.

Fabric inspection and detection of faults

Fabric quality control involves the control of a series of characteristics, such as dimensional stability, shade uniformity, colour stability at fusing and ironing temperatures, light and stain removal fastness, weft squareness, consistent tensile strength, wear resistance, resistance to seam sliding pressure. Finishing products must not hinder fusing, and must not cause fabric stripiness and creases; selvedge must be regular, not too loose, not too tight or too large.

To make these controls easier Italian inspection machine makers offer a series of options, suitable both for woven and knitted/elasticised fabrics. Programmable automatic winding machines are also offered for cutting optimisation.

An interesting development is a final control for measuring and controlling colour directly on any type of inspection table for any type of textile product. Thanks to an advanced system of colorimetric quality control an exact interpretation and evaluation of the readings is provided. Advantages include automatic calculation of tolerances, instrumental control of colour differences (center/selvedges, header/end), no need of tests for sample sets, and speeding up of the control process.

Piece transport from storehouse to spreading department

A keen problem is “what to do” with the flaw lengths appearing during spreading. A solution is the CAD marking system, which is able to study and calculate the various possibilities for fault cutting-out, and the number of superimposed fabric layers needed after flaw removing. This information, together those concerning length of marking, number of layers for each single step, size, fabric/colour variant, is to be stored in the central computer for subsequent use not only by the spreader but also the robotised truck (which has to draw pieces from the warehouse), and the carousel for feeding individual piece to the spreader.

Many options of spreading equipment provide flexibility in fabric handling, and are available from Italian manufacturers, either with cradle or programmed loading of the rolls without the help of the chuck.

Special solutions are offered for tubular fabrics, big rolls up to 400 kg, home linen. A high tech solution is a two-roll spreader, which may be used to obtain the multilayer stack for laser cutting the car safety air bags. This technology can be also applied for simultaneous spreading of the three layers composing the tie material or to couple already during preading filling and fabric of windcheaters.

New fabric spreading technologies are becoming popular: these technologies are the natural answer to a more and more pressing market request, that is tailor made clothing. Customers who are no more satisfied of already made-up suits are increasing more and more; they require tailor made clothing with fabrics and sizes chosen by them. To satisfy these requirements, new completely automated lines are being planned for the motion of fabric rolls, spreading and cutting of predetermined length fabrics which will feed the systems for shape cutting. These lines, inserted in CIM systems, allow the making up of “tailor made” suits at low costs and in short time.

Pattern grading and marking

For these two operations, in the sector of CAD for the clothing industry, a wide range of the most recent and known software packages has been developed enabling high operating speed thanks to personal computers of the latest generation. The system is composed of a workstation with digitizer table, where the identification of the pattern design is performed. The subsequent step is carried out on a workstation for the construction of the basic model and the marking. After completing these operations, the system is arranged for interfacing with automatic cutting.

Cutting systems and cutting machines

For the cutting room various systems are offered so to meet the most diverse requirements not only of the medium and big clothing manufacturers, but also for small sized companies. The wide range of machines offered can handle the cutting of single-layer fabrics up to 15.5 cm stocked piles.

Sewing machines

The sector of sewing machines shows continuous updating and improvement. The trend is towards the use of more and more flexible and automatic sewing units able to perform some sequential sewing operations. On the other hand there is still the need to manufacture low cost sewing machines for the developing countries. Since present day fashion needs lead more and more to continuous model changes, clothing manufacturers very often have to increase the number of machines, with consequent high investment. This problem finds a solution in adopting a flexible modular system putting together three basic units: a cylinder bed sewing machine, a cuttingsewing machine and a flat a flat bed unit that can be completed by a series of universal kit for loop stitch goods (used for underwear, corsetry and knitwear). Advantages claimed for this system consist in: a complete production system that carries out sewing operations with very high performance, possibility of modifying the initial configuration, adapting it to new production needs, possibility of technological updating without having to replace the machine, justifiable investment also in case of fashion changes. A machine with shortened cylinder bed on the left of the needles and differential feed is offered for top stitching of pre-existent seams. A new subclass unit for top stitching the seams on medium-heavy knitwear has been prepared for smoothly sew crossed seams with high thickness. It equipped with thread cutting device. Also launched a brand new unit for flat topstitched assembly seams with bartacking on light and medium outerwear in a single operation.

The automatic units adopting a multistitch method allow to reduce operation times by about 50/60%, reduce the operation steps and hence the dwelling time of the semifinished garment in the cutting room. A series of units carries out the flat and topstitched assembly seams in one single phase without interruption. They are equipped with two heads, the first one with horizontal needle bar for the assembly seams, the second one with vertical needle bar for topstitching. The sewing system adopts a new method for the introduction of the fabric into the automatic unit. In fact the two fabric edges to be assembled are presenting themselves in open state, with the right side turned towards the operator, making easier the coupling of striped and chequered fabrics. For attaching pockets on shirts, working clothes and pyjamas etc., machinery with flexible systems controlled by microchips that can fold pockets, sewing them, and pile the garments in an automatic cycle. These machines offer high productivity, constant quality and the possibility to programme various sewing patterns that can be adapted to the different pocket models. The wide range of models offered include high frequency “sewing” systems for synthetic fabrics, which fuse by means of an 800 W ultrasound generator and a vibrating ultrasound group. The fusion speed can programmed up to 50 m/min and is driven by means of a treadle.

Quilting

Quilts are a popular home decoration element. Electronics broadens potential of quilting machines making them more versatile. An Italian company is engaged in the production of a series of models which mount a serious challenge to machine embroidery. The newest models of quilters, can operate at around 1,000 stitches/minute and are built with a quilting width up to 114 ins (290 cm). With three needle bars the patterning potential is immense. Giant rotating hooks with 700-mm bobbins are used in this machine which has
tack and jump mode. This is a means of still further creating more interesting surface effects.

Developments on these machines is aimed to a system of automatically cutting embroidery threads, and this will serve to conserve thread when a needles produces a discrete pattern and then needs to travel to a different position to perform its next task.

Embroidery

The Schiffli embroidery machines are now offered with computer control. The design preparation for multihead embroidery machines is today a normal practice. Besides punching of patterns on graphic screens and advanced systems for data processing of machine programs, one can use laser discs containing 20,000 patterns each, and affording to  immediately write the embroidery design on the machine disc, so that production can start at once.

Knitwear linking

The knitwear linking is carried out exclusively to sew full-fashioned knitted goods which are loaded onto pins so that the ribs of both webs perfectly match thus avoiding the risk of sliding.

Linking machines can be quipped with one or two needles and hook- or straight-shaped needles (different stitch formation obtained). Linking machines can have internal needle (the stitch is loaded from the plain side) or external needle (the stitch is loaded on the reverse side). The working speed can reach 1,500 stitches per minute; the quantity of needles per inch ranges from seven to sixteen; in special machines it can range from 2 to max 24 needles per inch. It’s also worth mentioning that some knitwear linking machines are equipped with microcomputer to synchronise all the speed values: adjusting sewing speed, prefeeding of rib borders, and positive drive pullers, which are controlled individually by conventional motors, in order to allow accurate alignment of the ribs.

Ironing and pressing

This sector includes a great number of units that are used for different purposes, and sees the leadership of Italian makers.

There are automatic, pneumatic and rotary ironing presses for all pieces of clothing; ironing systems for intermediate and final ironing include pneumatic toppers for trousers ironing, steaming dummies, finishing cabinets, heated vacuum boards, and the blowironing units.

All ironing machines and systems are now equipped with electronic systems so that crucial parameters such as speed, temperature and pressure may be set. The safety systems installed have been further improved for a better safeguard of the staff operating on the machines.

Finishing

The importance of finishing is becoming more and more crucial in the textile/clothing sector thanks also to the new “informal comfort” standard suggested by the fashion dictations in the last few years which started in the past with a new kind of treatment for jeans. Now the finished garment needs to be a “high-profile” piece of clothing not only from a purely technical point of view but also in terms of esthetical content, which must be in line with the visual, hand, and colour trends.

A wide and continuously evolving range of washers and tumblers especially studied for garment washing, dyeing and drying have been developed to allow many kinds of treatments such as bleaching and stone washing, and to obtain delavé and used look. Also worth remembering is the continuous evolution of drum type washing machines and the driers, available in a vast range of models specifically designed for washing, dyeing and drying operations on garments.

Folding and packaging

At the end of the production line, garments are arranged with reference tags, put into a bag and packed according to the forwarding specifications. These operations are carried out by means of folding and packing machines (for shirts, home linen, and underwear the complete process of folding and packing is carried out automatically in only one operation). A series of other systems are used to pile-up, pack, wrap-up and tie-up the garments.

TOOLS USED IN GARMENT CONSTRUCTION


Besides a sewing machine in good condition, well selected sewing equipment and pressing equipment are essential for making garments of good quality and appearance. Sewing box / kit: First and foremost, one should have a box or basket with compartments for keeping the things needed for sewing.

SEWING AND EMBROIDERY TOOLS:

Hand Sewing Needles: They are found in sizes from the very fine 9 to the heavy 18. The best quality needles are made of hand ground steel. For hand sewing medium length needles with a short oval eye is selected. Crewel needles designed for embroidery work have a long oval eye.

Sewing Machine Needles:They are found in sizes from the fine 9 to the heavy 18. The needles are made to fit the specific make and model of each sewing machine. The needle size should conform to the weight, thickness, and kind of fabric.

Sewing thread: With the wide and ever increasing range of fabrics available in the market, it is important to know the right sewing thread for the various types of fabrics. The right kind of thread is important in sewing as both the thread and the garment should share the same characteristics, as they have to be laundered and ironed together, they should shrink and stretch together.

Pins: These come in different sizes for use in different fabrics. The right choice of pins is most essential for good workmanship, speed, and convenience in sewing. Use silk or stainless steel pins. The ball point pins are useful for fine knits. The other types of pins are dressmaker pin (a pin of medium diameter but quite suitable for most sewing needs), and silk (a very slender pin with a needle point to be used on delicate fabrics).

Thimbles: These are necessary for efficient and accurate hand sewing. A metal thimble should fit snugly on the middle finger of the needle holding hand. There are two types of thimbles: an open-ended thimble, preferred by tailors, and the more common closed-ended thimble, called the dressmakers thimble (Fig.2a).

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Embroidery Frame: This is used for keeping the fabric stretched while the work is being carried out.

Embroidery Threads: These are available in a variety of colours in six stranded skeins. One can use two or three strands at a time.

Stiletto: This is a sharp pointed instrument for punching holes in material. It is used for forming holes in material. It is used for forming eyelets in belts and for embroidery work.

Bodkin: This is a flat needle with a blunt end and a large eye for threading elastic and tape

CUTTING TOOLS

The following types of shears and scissors are made for both right-handed and left- handed cutting. All cutting tools must be kept sharp, clean, and grease-free for accurate cuts.

Bent-Handle Shears: They are 8 to 10 inches long (Fig. 2b). They are used for cutting all types of fabrics. Shears differ from scissors in that they have one small ring handle for the thumb and a large ring handle for the second, third and fourth fingers.

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Scissors: They are 5 to 6 inches long. They are used for light cutting, trimming, clipping corners, and cutting curves. These have round handles for both the blades. They are designed for snipping threads and trimming seams. They should be held so that the wider blade is above the narrower blade.

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Pinking Shears: They are 9 to 10 inches long (Fig. 2d). They produce a notched cutting line (zig zag) which gives a neat appearance to the inside of garments.

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Button Hole Scissors: These can be adjusted so as to cut button holes in any size required (Fig. 2e). They are useful if one needs to make many button holes

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Electric Scissors These are used in most sample rooms. They are ideal for cutting silk, nylon, and soft, hard-to-cut fabric (Fig. 2f).

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MEASURING TOOLS

Measuring Tape: It has a smooth surface that is clearly marked with increments of inches and centimeters on both sides. It is usually about ½ inch to ¼ inch wide and 60 inches long, and has 1/8 divisions (Fig. 2g). At one end of the tape is attached a brass strip about 3 inches long and at the other end, a small brass covering.

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Rulers: They are used in sample room which are either clear plastic or metal. It is useful to have 2 rulers: one is 1 inch wide and 6 inches long, and the second is 2 inches wide and 18 inches long.

Yardstick or meter scale: It is available in 36 inches or 45 inches in length in wood or metal. They are useful for checking grain lines when fixing pattern pieces on material and for drawing long seam lines on fabric or paper.

L Square: It is an L-shaped metal ruler; the long arm measures 24 inches, the short arm 14 inches. This has a perfect right angle corner and is used to draw lines at right angles at the time of drafting. It is helpful during the process of “straightening fabric” to check whether the corners of the fabric have got the right-angled structure

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Skirt Marker:
They mark hem length accurately. Markers are adjustable and are available for use with chalk powder or pins. A six-inch gauge can be made of cardboard or bought from a shop (Fig. 2i). It is useful as a measuring guide for marking width of hems, pleats, seam allowances etc. accurately. Notches are provided at regular intervals along the gauge. One edge of the notch is at right angles to the straight. While measuring or marking, use the straight edge of the notch as a guide.

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MARKING TOOLS

Tracing Wheel: It is used to transfer the pattern markings-including seams, darts and pocket placements to the wrong side of the fabric with the aid of tracing paper. The small serrated edge tracing wheel is appropriate for most fabrics (Fig.2j). A smooth edge tracing wheel is used on fine or knit fabrics to avoid snagging the yarns.

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Tracing Paper: It is a wax-coated paper used with the tracing wheel to transfer pattern markings to the wrong side of the fabric

Tailors Chalk: It is made of wax or stone chalk that is used to transfer markings to fabric when white carbon is not visible. Stone chalk is also available in pencil form. This is available in assorted colours and in rectangular or triangular shapes.

PRESSING TOOLS

Iron: This keep an automatic iron handy for pressing fabric before cutting, during construction and after the garment is completed.

Steam Iron: It has an adjustable temperature control, and is equipped with a thumb press for automatic steam. Distilled water is heated, and the resulting steam can be released with the thumb press while pressing.

Ironing Board:  It is used for hand pressing which is padded and of convenient height. One may use an ordinary table covered with sheet and blanket for this purpose.

Sleeve Board: This is a well-padded miniature of a full-sized ironing board and is used to press sleeves and hard-to-reach small details (Fig. 2k). It has a tapered end on one side and a round end on the other side.

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Press cloth: Fabric used for press cloth should be colourfast and should be washed or boiled to remove all sizing.

MISCELLANEOUS TOOLS

Awl: It is a small, sharp-pointed tool used to punch small, round holes for marking on paper or leathers.

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Seam Ripper: It is used to remove basting stitches and to rip out unnecessary machine stitches (Fig. 2m).

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Loop Turner: Is a long wire with a latch hook, used for turning bias strips to make spaghetti straps and narrow belts.

Dress Form: This is a padded form of body and may be made of wood, cardboard, plaster of paris, reinforced plastic. This is a necessity in all sample rooms for designing and fittings.

Paper: It is for pattern making purposes and fabric cutting. This soft paper comes in rolls of plain paper or paper with blue dots or other markings at set intervals.

Three-Way Mirror: It is used for model fittings.

Orange-stick: This is a long tool whose point can be inserted into the corners of collars, seams, etc., so as to give a neat pointed appearance.

Cutting board or table: This is a table of convenient height and size is a definite aid in cutting and constructing garments. 5’ x 3’ is a desirable size with 2″ x 6″ height.

Summary
A variety of tools and equipment are used for performing various functions such as sewing, cutting, measuring, pressing, etc. A knowledge about these tools will help us to choose the right tool to complete a particular task in the process of garment construction.

SEWING MACHINE TYPES


Deutsch: Nähmaschinenmechanismus. English: An ...
Image via Wikipedia

Sewing is a creative and interesting skill. The knowledge of sewing give a confident feeling when it is applied to the construction of garments. The earlier method of sewing by hand is not applicable for all stages of garment making. Therefore, considerable emphasis is given to machine sewing. There are several machines in the market today, each with its own desirable features and advantages. Sewing machines range from most basic having only simple lock stitch to the electronic machines that use advanced computer technology having various functions for example piping, binding, ruffling, pleating, darning, hemming and even making buttonholes and attaching fasteners. A good sewing machine is required to obtain quality products. One has to be familiar with the characteristics of different types of machines for selecting appropriate machine, depending upon the ability and requirements of the person.

TYPES OF SEWING MACHINES:

Sewing machines are now available in various models such as domestic model, tailor model, industrial model, portable and cabinet models. They may be operated by hand, treadle or electric motor.

Hand – Operated Sewing Machine:

This is the simplest form of sewing machine which is operated by hand. A detachable handle provided to the flywheel is used to operate the machine. This machine is generally suitable for domestic purpose because it does not help in speeding up the work.

Treadle Sewing Machine:

This machine is exactly like the hand sewing machine but it is operated by foot using an additional stand. In this type the balance wheel is operated by a belt with the help of lower stand, which is driven by feet. This machine operates faster than that of the hand-operated machine. This machine is suitable where there is no power supply. When handling
this machine both the hands are free to handle the fabric, speeding up the work. Even some of the heavy-duty machines are operated by this method.

Electric Sewing Machine:

This is the fastest sewing machine. One needs practice to handle it. In an electric machine the balance wheel comes to motion by a belt, which is attached to an electric motor.

PARTS OF A SEWING MACHINE AND THEIR FUNCTIONS:

The basic structure of sewing machine is the same whether it is hand-operated sewing, treadle sewing machine or electric sewing machine. The basic parts of a sewing are listed below and seen in Fig.1

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1. Spool pin: It is fitted on top of the arm to hold the reel.

2. Thread guide: It holds the thread in position from the spool to the needle.

3. Tension disc: The two concave discs put together with the convex sides facing each other. The thread passes between the two. The tension of the thread is adjusted by a spring and nut which increases or decreases pressure

4. Take up lever: It is a lever fitted to the body of the arm. Its up and down motion feeds the thread to the needle and tightens the loop formed by the shuttle.

5. Needle bar: This is a steel rod to hold the needle at one end with the help of a clamp. Its main function is to give motion to the needle.

6. Bobbin case: This moves into position to catch the top thread and form the stitch as the needle is lowered into the bobbin chamber.

7. Presser foot: It is fixed to the presser bar to hold the cloth firmly in position when lowered.

8. Presser foot lifter: A lever attached to the presser bar for raising and lowering the presser foot.

9. Stitch regulator: This controls the length of the stitch.

10. Bobbin winder: A simple mechanism used for winding thread on the bobbin.

11. Fly Wheel: When this is made to revolve, it works the mechanism of the motion

12. Clutch or Thumb Screw: This is in the center of the fly wheel and it engages and disengages the stitching mechanism.

13. Slide Plate: A rectangular plate, which facilitates the removal of the bobbin case without lifting the machine.

14. Needle Plate or Throat Plate: A semi-circular disc with a hole to allow the needle to pass through it.

15. Feed dog: This consists of a set of teeth fitted below the needle plate. It helps to move the cloth forward while sewing.

16. Face plate: A cover which on removal gives access to the oiling points on the needle bar, presser bar and take-up lever.

17. Spool pin for bobbin winding: Spool of thread is placed on this at the time of bobbin winding.

PREPARATION FOR STITCHING

Before starting actual machining, you should check that the needle of the machine is of correct size, is sharp and correctly set. The bobbin should be evenly set. Briefly, the various steps of prepreparation are:

• Winding the bobbin
• Upper Threading
• Drawing the bobbin thread
• Tension adjustments
• Pressure and feed adjustments
• Selection of thread and needle

A perfect stitch can be obtained only when the thread selected is suitable to the material to be stitched and the needle is of the correct size. For stitching on delicate thin fabrics, use fine thread and fine needle. For heavy fabrics, needles and thread size should be larger. The following Table 1 will be a guide to help selection of appropriate needle and thread sizes.

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Types of Threads

The natural fibre threads available in the market are cotton and silk. Synthetic threads are usually made from polyester and terylene. Threads whether natural or synthetic are produced in various thickness: higher the number, finer is the thread and smaller the number, coarser is the thread. It is important to remember that the same thread should be used for the bobbin and top spool.

Selection of needles

Machine needles are selected according to the weight and other characteristics of the fabric, as well as the thread type being used for construction. Generally, a needle should be fine enough to penetrate the fabric without damaging it and yet have an eye, which is big enough so that the thread does not fray or break. Needles come in various sizes, from very fine (size 9) for light weight fabrics to thick (size 18) for very heavy weight and dense fabrics.

COMMON MACHINE TROUBLES

The sewing like any other machine, gives troubles of stitching like thread breaking, uneven stitching, puckering, bending and breaking of needle, looping of threads, skipping of stitches, etc. Little problems with the sewing machine can be very irritating and time consuming. They can happen to even the most experienced seamstress. A person operating the machine should be able to rectify these and solve the problems. Some of the common machine problems are listed below:

• breaking needles
• looping of stitches
• skipping stitches
• variation in stitch length
• puckered seams
• upper thread breaking
• lower thread breaking
• machine not feeding properly
• machine working heavily
• layers feed unevenly
• fabric does not feed in straight line
• cause damage to fabric
• Puckering on both layers of fabric
• Puckering on under layer only
• Shows feed marks on the under side
• Fabric is damaged or holes around the stitches

CARE AND USE OF SEWING MACHINES

A sewing machine needs care for its smooth running. It should be cleaned and oiled regularly to ensure satisfactory sewing and long life. When not in use, your machine should be covered to prevent dust accumulation on it. Use a small dry brush or old toothbrush and soft cloth to remove dust and lint. You should always remove lint deposits, dust and thread bits before oiling any part of the machine. Use a pointed instrument like a needle to pick out the bits of thread and lint that cannot be brushed out.

It is necessary to oil and lubricate the machine periodically. If the machine is used everyday, oil it once a week. After oiling, wipe off the surplus oil and place a piece of folded fabric under the presser foot to absorb any excess oil. To oil thoroughly, remove the upper thread, needle plate, slide plate, face plate, bobbin case, needle and presser foot. Oil the holes on the underside first, after cleaning and then proceed to the upper side. Use only few drops of oil in each hole. Never use coconut oil. Machine oil of different brands may be used for different models of sewing machine, but should be used as recommended in the instruction book.

If the machine becomes gummed with oil, put a drop of kerosene or petrol in each oil hole and joints and run it rapidly for several minutes. Wipe off and re-oil it with machine oil. The motor of electric sewing machine should be greased periodically.

Summary
The knowledge of sewing give a confident feeling when it is applied to the construction of garments. The various parts of a sewing machine and their functions helps one  to understand the working of a sewing machine. A brief up on the common machine problems help us to understand and rectify the problems. Above all the care of sewing
machine is rather important for a long service of the machine.

Quality Control Aspects of Garment Exports


Introduction

For every industry or business, to get increased sales and better name amongst consumers and fellow companies it is important to maintain a level of quality. Especially for the businesses engaged in export business has to sustain a high level of quality to ensure better business globally. Generally quality control standards for export are set strictly, as this business is also holds the prestige of the country, whose company is doing the export. Export houses earn foreign exchange for the country, so it becomes mandatory to have good quality control of their products. In the garment industry quality control is practiced right from the initial stage of sourcing raw materials to the stage of final finished garment. For textile and apparel industry product quality is calculated in terms of quality and standard of fibres, yarns, fabric construction, colour fastness, surface designs and the final finished garment products. However quality  expectations for export are related to the type of customer segments and the retail outlets. There are a number of factors on which quality fitness of garment industry is based such as – performance, reliability, durability, visual and perceived quality of the garment. Quality needs to be defined in terms of a particular framework of cost. The national regulatory quality certification and international quality programmes like ISO 9000 series lay down the broad quality parameters based on which companies maintain the export quality in the garment and apparel industry. Here some of main fabric properties that are taken into consideration for garment manufacturing for export basis:
• Overall look of the garment.
• Right formation of the garment.
• Feel and fall of the garment.
Physical properties.
Colour fastness of the garment.
• Finishing properties
• Presentation of the final produced garment.

Sourcing of Fabrics

There are certain problems that could be faced by garment manufacturers when sourcing for certain fabrics, so precautions should be taken for it beforehand to minimize the problems. The garment exporters source cotton fabrics mainly from handloom sectors, powerlooms and mills. Each of these sectors presents their own unique set of problems to the garment exporters. Sourcing cotton from handloom sectors might present some set of problems like colour variation, missing ends and picks, irregular weaves and unreliable supplies. However, the handloom sector is significant source of heavier cotton. Common problems faced in powerloom cotton sourcing are broken ends and reed marks, thick and thin places, difference in width and massive variation in costing. The major problem in mill-made fabric sourcing is to meet huge demands from the mills. Fabrics have to be ordered well in advance in mills and the long time taken for producing the fabric is a matter of concern for garment exporters. Mills generally hesitate to take small orders which pose a problem for small scale exporters.

It is not that sourcing problems which only confined to cotton fabrics, but also to other fabrics as well. In silk garment industry there are some sorts of problems faced by silk garment exporters. Some of the problems that could be faced by silk garment exporters are as follows:

• Shortage of imported silk yarns in the quantities required, as a result delivery is delayed.
Silk material is very vulnerable to stains during manufacturing process as well as stocking, staining results in rejection so a lot of care has to taken during these procedures.
• Roll length of the silk yarn is often insufficient.
• Colour fastness of dyed silk material is sometimes not satisfactory.
• There are also chances of warp breakage.

Basic Thumb Rules for Garment Exporters

For a garment exporter there are many strategies and rules that are required to be followed to achieve good business. The fabric quality, product quality, delivery, price, packaging and presentation are some of the many aspects that need to be taken care of in garment export business. Some rules that are advisable for garment exporters are listed below:

• Quality has to be taken care by the exporter, excuses are not entertained in international market for negligence for low quality garments, new or existing exporters for both it is mandatory to use design, technology and quality as major upgradation tools.
• Apart from superior quality of the garment, its pricing, packaging, delivery, etc has to be also taken care of.
• The garment shown in the catalogue should match with the final garment delivered.
• It is important to perform according to the promises given to the buyer, or else it creates very bad impression and results in loss of business and reputation.
• In international market, quality reassurance is required at every point.
• Proper documentation and high standard labels on the garment are also important aspects as these things also create good impression.
• Timely delivery of garments is as important as its quality.
• If your competitor has the better quality of garment in same pricing, it is better to also enhance your garment quality.
• Before entering into international market, garment exporters have to carefully frame out the quality standards, or else if anything goes wrong it could harm the organization. And after that strictly follow it.
• The garment quality should match the samples shown during taking the orders.
• The garment exporters should know to negotiate a premium price after quality assurance is done.

Quality is a multi-dimensional aspect. There are many aspects of quality based on which the garment exporters are supposed to work.

• Quality of the production.
• Quality of the design of the garment.
• Purchasing functions’ quality should also be maintained.
• Quality of final inspection should be superior.
• Quality of the sales has to be also maintained.
• Quality of marketing of the final product is also important as the quality of the garment itself.

See to it that………..

There are certain quality related problems in garment manufacturing that should not be overlooked: Sewing defects – Like open seams, wrong stitching techniques used, same colour garment, but usage of different colour threads on the garment, miss out of stitches in between, creasing of the garment, erroneous thread tension and raw edges are some sewing defects that could occur so should be taken care of. Colour effects – Colour defects that could occur are – difference of the colour of final produced garment to the sample shown, accessories used are of wrong colour combination and mismatching of dye amongst the pieces.

Sizing defects – Wrong gradation of sizes, difference in measurement of a garment part from other, for example- sleeves of ‘XL’ size but body of ‘L’ size. Such defects do not occur has to be seen too. Garment defects – During manufacturing process defects could occur like – faulty zippers, irregular hemming, loose buttons, raw edges, improper button holes, uneven parts, inappropriate trimming, and difference in fabric colours.

Conclusion

Quality is ultimately a question of customer satisfaction. Good Quality increases the value of a product or service, establishes brand name, and builds up good reputation for the garment exporter, which in turn results into consumer satisfaction, high sales and foreign exchange for the country. The perceived quality of a garment is the result of a number of aspects, which together help achieve the desired level of satisfaction for the customer. Therefore quality control in terms of garme

Quality Control Aspects of Garment Exports


  • Introduction

For every industry or business, to get increased sales and better name amongst consumers and fellow companies it is important to maintain a level of quality. Especially for the businesses engaged in export business has to sustain a high level of quality to ensure better business globally. Generally quality control standards for export are set strictly, as this business is also holds the prestige of the country, whose company is doing the export. Export houses earn foreign exchange for the country, so it becomes mandatory to have good quality control of their products. In the garment industry quality control is practiced right from the initial stage of sourcing raw materials to the stage of final finished garment. For textile and apparel industry product quality is calculated in terms of quality and standard of fibres, yarns, fabric construction, colour fastness, surface designs and the final finished garment products. However quality
expectations for export are related to the type of customer segments and the retail outlets

There are a number of factors on which quality fitness of garment industry is based such as – performance, reliability, durability, visual and perceived quality of the garment. Quality needs to be defined in terms of a particular framework of cost. The national regulatory quality certification and international quality programmes like ISO 9000 series lay down the broad quality parameters based on which companies maintain the export quality in the garment and apparel industry. Here some of main fabric properties that are taken into consideration for garment manufacturing for export basis:
• Overall look of the garment.
• Right formation of the garment.
• Feel and fall of the garment.
Physical properties.
• Colour fastness of the garment.
Finishing properties
• Presentation of the final produced garment.

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Garments Manufacturing Sequence


Garments manufacturing follows a flowchart where in each steps definite works are completed to carried out a complete garments. Here I will show you all of the garments manufacturing steps that you must follow to make a garment.

1. Design/ Sketch:

Design/Sketch
For the production of knit garments, or woven garments a sketch of a particular garment including its design features is essential to produce on paper so that after manufacturing of that garment could be verified or checked whether could be done manually or with the help of computer.

2. Pattern Design:

Hard paper copy of each component of the garment of exact dimension of each component is called pattern. The patterns also include seam allowance, trimming allowance, dirts, and pleats, ease allowance, any special design etc affairs. Pattern design could also be done manually or with the help of computer.

3. Sample Making:
The patterns are used to cut the fabric. Then the garment components in fabric form are used to sew/assemble the garment. Sample garment manufacturing is to be done by a very efficient and technically sound person.

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4. Production Pattern:
The patterns of the approved sample garment are used for making production pattern. During production pattern making, sometimes it may be necessary to modify patterns design if buyer or appropriate authority suggests any minor modification.

5. Grading:
Normally for large scale garments production of any style needs different sizes to produce from a set of particular size of patterns, the patterns of different sizes are produced by using grade rule which is called grading.

6. Marker Making:


All the pattern pieces for all the required sizes are arranged n the paper in such a way so that maximum number of garments could be produced with minimum fabric wastag4e. Markers are made for 6, 12, 18, 24 etc. pieces. Marker is also useful to estimate fabric consumption calculations.

7. Spreading:
It is the process of arranging fabrics on the spreading table as per length and width of the marker in stack form. Normally height of the lay/fabric is limited upto maximum six inches high. But 4 inch to 5 inch height of the lay is safe.

8. Fabric Cutting:


On the fabric lay/spread the marker paper is placed carefully and accurately, and pinned with the fabric to avoid unwanted movement or displacement of the marker paper. Normally straight knife cutting machine is used to cut out the garment component as per exact dimension of each patterns in stack form, care must be taken to avoid cutting defects.

9. Sorting/ Bundling:
After cutting the entire fabric lay, all the garments components in stack form is shorted out as per size and color. To avoid mistake in sorting, it is better to use code number on each pattern.

10. Sewing or Assembling:

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It is the most important department/ section of a garment manufacturing industry. Sewing machines of different types are arranged as a vertical line to assemble the garments. Sequence of types of sewing machine arrangement depends on sequence of assembling operations. Number of sewing machine per line varies from 20 nos to 60 nos depending on the style of the ga4rmnet to be produce. Production pr line pr hour also varies from 100 to 150 pieces depending on specific circumstances. Number of sewing machine arrangement per line may be upto 60 depending on design and out put quantity of garment.

11. Inspection:
Each and every garment after sewing passes through the inspection table/ point, where the garments are thoroughly and carefully checked to detect/find any defect if present in the garment. The defects may be for example variation of measurement, sewing defect, fabric defects, spots etc. if the defect is possible to overcome, then the garment is sent to the respective person for correction. If the defect is not correctionable, then the garment is separated as wastage.

12. Pressing/ Finishing:

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After passing through the inspection table, each garment is normally ironed/ pressed to remove unwanted crease and to improve the smoothness, so that the garments looks nice to the customer. Folding of the garment is also done here for poly packing of the garments as per required dimension.

13. Final Inspection:

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It is the last stage of inspection f the manufactured garments on behalf of the garment manufacturing organization, to detect any defective garments before packing.

14. Packing:
After final inspection, the garments are poly-packed, dozen-wise, color wise, size ratio wise, bundled and packed in the cartoon. The cartoon is marked with important information in printed form which is seen from outside the cartoon easily.

15. Despatch: The cartoons of the manufactured garments are delivered or placed in the despatch department or finished product godown, from where the garments lot is delivered for shipment.