Pressing Equipment and Methods Basic components of pressing

Pressing Equipment and Methods

Basic components of pressing: The main elements of the pressing process are heat, pressure and moisture, which deform fibres, yarns and fabrics to accomplish the required effect. 1. Heat – It is necessary to soften the fibres, stabilise and set the fabric in the desired shape. Temperature must be selected based on the fibres, yarns and fabrics. 2. Steam (Moisture) – It is fastest way of transmitting the heat onto the fabric. Steam and heat are essential to ease the fabric from tension and make the fabric with adequate flexibility so that it can be moulded to get the required contour. 3. Pressure – It is applied to change the form and increase the durability of the moulding. Pressure could be applied by means of a mechanical device or steam. 4. Drying – Subsequent to the steam and pressure application on the fabric, the garment panel or finished garment must be dried and cooled; thus, the fabric can return to its regular moisture content and steady condition. This could be done by removing the surplus water from the fabric by means of a vacuum action which cools it at the same time. 5. Time – The time period for which the garment is exposed to steam, pressure and drying depends on the type of fabric being pressed and there will be an optimal time period for each component.

Types of pressing equipment and methods in apparel industry: • There is a large range of equipment available for the pressing of garments, from the simple hand steam irons to the sophisticated vertical front and back pressing robot. The various equipment used are iron, steam presses, steam air finisher, steam tunnel, pleating and permanent press.

Classification of pressing equipment: 1. Solid Pressure Equipment (Pressing Equipment) • Pressing irons • Buck presses • Mangle presses • Block presses • Form presses • Pleating presses • Creasing machines: Edge folders

2. Moisture Pressure Equipment (Steaming and Wetting) • Wetting tanks: London shrinkers and auxiliary equipment • Sponging machines • Steam guns and jets • Steam chambers • Autoclaves

3. Heat Energy Equipment (Heating and Baking) • Thermoelectric machines • Hot plates • Casting equipment • Dry heat ovens

Types of Pressing Equipment: • Solid surface pressing equipment uses a firm surface to apply pressure while steam and heat mold the fabric, garment or garment parts. Pressure may be applied through a rolling action, gliding action or compression.

Hand irons: Iron which is known commonly as iron box has been in existence for a very long time with the traditional one being used with heat generated using charcoal. There were also irons which were heated by gas flame inside the metal casting and it was mainly used in touching up of men’s jackets. However in recent times, steam and electric irons are used commonly

• Normally, hand irons are available in different shapes and weights: • Narrow hand irons are used for seam opening on sleeves and trouser legs. The wrinkle marks on the garment are avoided by the narrow sole construction of the steam iron as well as curved and narrow ironing bucks. Teflon-coated soles should be used for ironing fabrics that are sensitive to luster. • Wide ones for flat shapes • Pointed shape

Steam press/buck press: • Steam presses commonly consist of a static/fixed buck and a head of complementary shape closing onto it, thereby sandwiching the garment to be pressed. It consists of a frame housing the buck which is normally in round shape for pressing different garments and linkages to close the head by a scissor action. • Steam is passed to head and buck using a pipe system. Adequate controls are provided for controlling head closure and vacuum. Vacuum is created to provide suction through the buck using a vacuum system. The typical pressing cycle is as follows

Flow chart of Steam press/buck press: A garment need to be pressed is fixed in the buck ↓ The buck head closes and locks ↓ Then steam is applied to the head or the buck to press the garment for a predetermined time ↓ The buck head is released ↓ Vacuum is applied to the garment to cool and dry it ↓ The garment then moved around the buck for the next part of it to be pressed

Double legger-pressing machine: Double legger-pressing machine is used for pressing trousers, and in this machine both the legs are pressed simultaneously with the top hanging down between two separate bucks. These machines consist of vertically acting heads, carousels and microprocessor controls. Heat resistant silicone foam is used for covering bucks of steam presses and tables used with irons and vacuum boards and the outside being covered with a woven polyester cover. Sometimes stretch nylon is used with the highly contoured bucks https: //www. youtube. com/watch? v=a. Ss 3 u. Rjk. Xt. M

Steam air finisher: • This equipment is known as a form press, puffer or a ‘dolly’ press. • It has a compressed air system, frame for a steam distribution system and a pressing form made of a canvas bag in the suitable silhouette of the garment to be pressed. • Form size is as like garments body but there is no sleeve. • Normally 8 seconds for steam supply and 8 seconds for hot air supply https: //www. youtube. com/watch? v=sf-X_rle. Bds https: //www. youtube. com/watch? v=SBm. RNYS_ymw Uses: • Mainly used for T-shirt, blouses, night dresses, sports wear etc • Moreover used forpressing Jeans shirt, pants, jackets etc.

Advantages: • Easy to remove unwanted crease and crinkles. • Less time consumption. • Separate pressing form is required for separate garments. Disadvantages: • Special care is required for knitted fabric pressing • There is no system to make crease.

Steam Tunnel • Without application of pressure, pressing is done in this process. • Tunnel finishers are used for finishing knitted and woven goods, They can be used for manmade fibre garments and their blends also. • In this finishing process, the garments are put on hangers or frames and fed through a cabinet using a motorized rail/conveyor. • The rail bears the hanger through different chamber in a tunnel. • Temperature is controlled in first chamber and creases are removed from fabric relaxation and gravitational force, • Second chamber blows hot air and fabric becomes dry. • These tunnels are incorporated with infrared drying in some cases. • https: //www. youtube. com/watch? v=Bf. Dsk. B 3 rl. Io

Creasing machines: • This unique kind of small press performs an exceptionally useful function. Creasing machines are used to fold over and press the edges of clothing components such as pockets or cuffs to prepare them for easy sewing. Blades are used to create creases and folds. The component is kept over a die with blades aiding in forming creases around it and required pressure is exerted during pressing cycle. Creasing machine is actually preparation underpressing machine. Creasing machine principles and components are basically alike regardless of type or style of the section being creased by the machine. • https: //www. youtube. com/watch? v=sim. Kq. IQ 5 b. Cc

Carousel press: • Carousel press is a new development in pressing operation in which a pair of bucks is provided that rotates between operator and the head. The head can be of single or double based on the bucks being identical or an opposite pair for pressing the left and right of a garment part. In this press, scissor action and vertically acting heads can be used. • https: //www. youtube. com/watch? v=u. R 1 TOgu. THTM

Pleating: Pleating is the process of creating pleats in the garment. Pleats are a type of fold actually formed during stitching by doubling fabric upon itself and securing it in place. However, these pleats can also be introduced in pressing by creating a set of creases in the garment and making it set by pressing. The pleats can even be according to a geometrical pattern. Pleating is done by using pressure, moisture and heat. There are two types in machine pleating. One is a blade machine in which pleats are formed by the action of blades and then set by heat and pressure when they pass through a pair of rollers and the other type is a rotary machine in which the rollers are fitted with complimentary dies. Crystal pleating, hand pleating, box pleats and fanshaped pleats are some of the examples shown in below figure.

Block or Die pressing: In die pressing, the fabric is kept over a fixed die prior to the application of steam, heat and pressure. This is normally used for shaping and moulding of hat and gloves during the manufacturing process. Another variety of an automated die pressing machine is utilised for combined folding and creasing of patch pockets as well as pocket flaps, in which the operator has to keep the components to be pressed over a die and engages the machine for folding and creasing. https: //www. youtube. com/watch? v=kkv. DDfmk. BCw https: //www. youtube. com/watch? v=i. He 6 t. Kbil. J 4

Permanent press: • The permanent press method normally results in reduction of fabric strength. This method was developed for producing better crease recovery of cellulosic fabrics. The process involves processing the fabrics during its manufacture with a resin. A permanent press fabric is processed after the resin treatment and is then made into garments. The method is commonly used for trousers to introduce the creases at the seams and hems and down the front and back. The garments are then passed through an oven to cure the resin in the fabric.

Thank you