A COMPRIHENSIVE DICTIONARY OF TEXTILE


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by  : Mason Brown

Textiles are fibres that are spun into yarn or made into fabric by weaving, knitting, braiding, and felting. The term is now applicable to natural and synthetic filaments, yarns, and threads as well as to the woven, knitted, felted, tufted, braided, bonded, knotted, and embroidered fabrics. The spinning and weaving were one of the first crafts that is believed to have been practiced as early as the New Stone Age. In ancient Egypt, the earliest textiles were woven from flax in India, Peru, and Cambodia, from cotton in the Southern European; from wool in China.

Textile also includes non-woven fabrics produced by mechanically or chemically bonding fibres. Computerised textile mill with multiple machines run continuously to produce textiles in the modern market. In a mill, the initial stage of processing fibre into fabric is almost entirely coordinated and controlled by computer. Computers are able to execute complex weaving and spinning jobs with great speed and accuracy. Most are equipped with monitoring sensors that will stop production if an error is detected.

The initial stage of textile manufacturing involves the production of the raw material either by farmers who raise cotton, sheep, silkworms, or flax or by chemists who produce fibre from various basic substances by chemical processes. The fibre is spun into yarn, which is then processed into fabric in a weaving or knitting mill. After dyeing and finishing, the woven material is ready for delivery either directly to a manufacturer of textile products to finally get stitched into clothes that we wear.

This book gives you an insight for terminology used in the textile industry. It should be helpful for everyone who is associated with garment, and textile industry.

To download this book please click on the following link.

http://www.4shared.com/office/SGs4M_TZce/2010_A_Comprehensive_Dictionar.html

Production Planning and Scheduling Software for the Textile Industry


Introduction

As far as enterprise resource planning systems (ERP) are concerned, the textile industry may still be a manageable affair. But the moment you talk about developing a production planning and scheduling software for this industry, you are asking for a difficult task to be performed. Many a veteran has failed in attempting to achieve this feat.

Challenges

Some of the unique challenges posed by the textile industry to any production planning and scheduling software vendor are discussed here. These challenges can be grouped as raw material concerns, manufacturing lead time, manufacturing constraints, orders, and inventory.

Raw material concerns involve high raw material costs and seasonal raw material procurement cycles. Cotton, for example, is a seasonal commodity; therefore, the availability and price will change throughout the year. High raw material cost is another issue. Raw material costs may constitute as high as 60 to 70 percent of the total costs.

Manufacturing lead time can also pose challenges. Manufacturing lead times can be excessive, sometimes more than two months. This is because the raw cotton production process, for example, has to go through many processes and most of them have huge lead time requirements. Looms in particular take the most lead time. A loom machine can make only 500 meters of fabric in a day whereas typical order lengths are in the range of 25,000 to 50,000 meters range.

Most of the manufacturing processes also have high setup times. Quality analysis time also runs high as the finished cloth needs to be manually inspected for defects. Extra lead times also result due to unavoidable generation of inventory in the form of extra meters than the ordered lengths.

Another challenge involving manufacturing is that different processing speeds occur at different work centers, which must also be included in the equation. Dyeing machines, warping machines, spinning machines run at speeds of 30,000 to 50,000 meters of yarn per day but looms run at 500 meters of fabric per day. Because of this, there may be only 2 to 5 dyeing machines, but there may be as many as 500 looming machines in the same plant.

Likewise there are different processing requirements on the same production line. For example, up until the dyeing process, the manufacturing process fits orders that are big and similar. But at looming, the manufacturing process fits many smaller and varied orders. This poses a real challenge as fitting these two diametrically opposite requirements is next to impossible to do.

Another issue is the unpredictable generation of second quality textile and the fact that variations in color and shade is only known after the fabric has been woven and finished (though they are caused back at the dyeing stage). This can result in a lot of rejected material being processed unnecessarily, thus adding to manufacturing costs and processing time.

These manufacturing constraints ultimately impact customer orders. Because the production rates are very low on looms, customer orders are broken into smaller sub-orders, and the sub-orders are distributed to many looms to reduce the lead time for individual orders. However, variations in the color or shade from the order can also emerge, which, as explained earlier, are detected at the end of the entire process.

Not surprisingly, inventory is another challenge faced by the textile industry because there is a high generation of extra finished products. In addition to extra material resulting from second quality and color shade variations, extra yarn moves through the entire production cycle. Up to dyeing stage, the work-in-process (WIP) is in yarn form and the length of this yarn is fixed at the yarn making stage. It cannot be cut as per order lengths. These extra meters travel through the production cycle and end up as excess inventory, which is later adjusted in the next planning cycle. Consequently, plant capacity is inefficiently utilized due to unavoidable generation of extra meters—more than the lengths ordered.

After going through these constraints, it is obvious that it is difficult to develop production planning and scheduling software for the textile industry. Only a veteran who has in-depth industry knowledge as well as knowledge of how to tackle these constraints in the implementation can develop a software for planning and scheduling for the textile industry.

Dyeing versus Looming

It is very important to understand the different requirements at the dyeing and looming processes so a suitable planning and scheduling software can be suggested. The dyeing and looming processes are the true bottlenecks in the entire production cycle of all textile plants. Both dyeing and looming have high setup time, high production time, and high change overtime, but looms are far slower than dyeing machines. Looming is more like a warehouse with a lot of WIP inventory called grey stock and this grey stock is on many looming machines, in small quantities. Dyeing machines, however produce long sets of warp (dyed yarn). One set of warp can be produced by one dyeing machine in one day but the warp can only be consumed by at least 50 looming machines in one day. To keep the ability to produce many kinds of fabric, the manufacturers generally install many kinds of looming machines. All of these looms are fed by only 2 to 5 dyeing machines. Due to these factors the dyeing area is always hard-pressed to feed the looms with small lengths and different types of dyed yarn for the next work orders in line.

So dyeing machines are better suited to produce big quantities of dyed yarn of the same type, (e.g. same color and same number of ends). For example, if the ordered length of fabric is 25,000 meters and the order has been broken into 10 work orders at 10 looms, then it will take 5 days to finish the WIP at looming. This is if all the work orders are done simultaneously and speed of looms are 500 meters of fabric woven per day. A single dyeing machine will produce 25,000 meters of warp in half a day.

Solutions

These challenges in the textile industry can be met by conducting a profitable to promise analysis; grouping, breaking, and sequencing orders; and by routing WIPs. In the textile industry, orders are considered more like combinatorial meters rather than individual order meters, so the same type of orders can be grouped and sequenced to achieve production efficiency as well as reduce inventory creation. All WIPs can also considered the same way for the same purpose.

Profitable to Promise Analysis

Businesses in the textile industry mostly gets varied orders in terms of rate per meter, quantity, fabric type etc. Because of this, each order has to be evaluated on profitability, customer service levels and long and short term goals of the company. Profitable to promise analysis allows the business to find out if the particular order will be profitable to make by considering the costs of raw material, process, inventory, and other factors against the price the customer is willing to pay. Thus it can be seen that some orders will be a lot more profitable than other orders. This analysis is perfectly possible if you have the right software tool, which can provide you with this kind of information.

If raw material availability, machine capacity, and production lead time are known at the time of order taking, then it is possible to give a definite delivery date to the customer. This is known ascapable to promise. If we can also provide information about customer, production, inventory, stock out, material, and other overhead costs down to the item level, and then compare all incurred costs to the selling price, it will be possible to decide whether the incoming order should be taken and what priority it can be assigned, at the time the order is being taken. This functionality is very important for the textile industry.

In conjunction with above mentioned factors, a planning system that is also capable of grouping, breaking, and sequencing orders while it is doing total lead time calculations to determine a delivery date will solve many production planning problems. It will eliminate waste, reduce the generation of extra inventory, increase machine capacity utilization, increase customer service levels, eliminate stock out costs, and reduce production costs.

Grouping, Breaking, and Sequencing Orders

Grouping, breaking, and sequencing orders will also help to overcome textile production challenges. Group smaller orders at dyeing process. The same dyeing WIPs can be grouped so the generation of extra meters can be minimized. Break bigger orders into many smaller orders at dyeing, and sequence them with other orders. Loom areas typically have many kinds of loom machines which can produce different kinds of fabric but at very slow rates. If big orders of same material are continuously coming from dyeing, they will only go to a particular loom machine which can process it; other loom machines which cannot use these warps will go idle for want of material. Another way to minimize set up time is to sequence WIP orders with the same color at the dyeing process. This will minimize the set up time to change of color. Also, breaking individual orders into many parts will create many work orders for the same order at looming process. This will minimize lead times significantly at looming.

Also, look for already existing inventory in the form of extra meters at looms and finished stock in the inventory to allocate these meters against the matched fresh orders and plan for the remaining meters.

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


The hazards in the textile industry


Every environment in which a working activity is performed, presents higher or lower accident hazards. The textile industry is characterized by the presence of a wide typology of machines and equipment, with automatic or manual transport systems connecting the various machines and departments, with dwell and storing areas; therefore the maximum attention must be paid by the operator, who has to comply scrupulously with the procedures and the active and passive safety systems with which modern machines are largely equipped. Often the distraction or the excess of ″confidence″ with the machines are the occasions for accident hazards. The hazards can also be increased by the environmental conditions of certain departments, by the kind of organization and by the existing work paces.

The risks of damages and diseases for the human organism in the textile industry can have following causes:

1) unhealthy microclimate: this is the case in particularly of the dye-houses, the environment of which is characterized by a high humidity level and by the presence of more or less harmful or irritant fumes, which are often associated with high temperatures and with an insufficient change of air. Also in certain spinning departments the necessary humidity rate, often combined with a certain presence of dust in the air, can result in breathing problems. The fibre dust which is emitted mostly when processing vegetal fibres can cause, in the more sensible subjects, an irritation of the bronchus, associated with a continuous production of mucus, and originate with the time chronic diseases as pharyngitis, tracheitis and bronchitis;

2) noise: noise represents in various departments and above all in weaving mills a problem of primary importance, especially if there is not enough room available and no  dequate
soundproofing intervention on the machine and on the rooms have been carried out. In such cases the alternative is the use of individual safety devices. A high noise level can  entail a reduction in the functions and other secondary collateral effects;

3) illumination, working position, precision, rhythm, repetitiveness, turnover system: various tasks require a considerable stress on the sight, or need body postures which have to be maintained long time, or require much attention, rapidity of execution, repetitiveness at very short intervals, temporary adaptations which can be the source of various pathologies both at physical and at psychical level.

Noise in the weaving rooms

In the textile industry, the noise problem in the various working departments is a cause of serious concern. The highest noise levels are to be found in the weaving rooms, where the operators are exposed to levels of 94 to 100 dBa. The needs of having the possibility to control fabric quality prevent any casing or partial shielding of the weaving machines, it is however possibile to correct the acoustics of the working room. The mostly used materials are:
1. glass wool baffles put in a glass fabric envelope and hang up on the ceiling;
2. glass fibre panels with an interspace between panel and adjoining wall;

These measures, unfortunately, are not very effective, so that the personnel is anyway compelled to use the devices for individual protection. In fact these measures reduce the noise level only by 1 to 1,5 dBa between the weaving machines and by 2 to 3 dBa between the beams and in the department passageways. The above mentioned modest results, typical of the weaving rooms, are due to the preponderance of the direct waves (coming from the noise sources) over the waves which are reflected by other bodies and to the distance of the sound absorbent material from the noise sources. The devices for individual protection which the workers have to use against noise are of various types and give different results with the variation of the frequency. There are devices which protect better at high frequency values (1000-8000 Hz) and others which are more efficient at low to medium frequency 125-1000 Hz).

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Noise origin and problems in weaving machines

Noise is caused by the vibration of the mechanical parts of the machine. These parts can be either in motion (various kinematic motions) or standing (structural parts, boxes, casings). The moving parts are the main origin of vibrations, which are then transmitted to the other parts of the machine. The vibrations are the higher, the more intense are the load variations to which the moving elements are submitted: sley, heald frames, weft inserting elements.

These movements are alternative motions and have rather high operation frequency levels; as such motions generate the maximum load variation values on the involved  mechanical elements, it is easily understandable that the resulting vibrations and the pertaining noise, can attain very high values.The noise of a machine depends therefore to a very large extent on the operating speed but also on the machine equipment viz. on its composition, as this entails a different quantity and typology of the mechanical units, each with different vibration mode. For this reason the weaving machine manufacturers are following two well known basic lines in their production:

1. noise reduction already at the designing stage;
2. reduction of the noise reaching the operator by means of physical barriers between the noise sources and the subject (casings).

A further possibility could be, as previously indicated, the modification of the mill acoustics. In fact, although a great deal of progress has been accomplished to reduce noise in the weaving rooms, there is still a long way to go.

We need only to consider that the noise emitted by a modern rapier machine is about 90 dBa (maximum level of acoustic pressure in 8 hours per day for a single person at 1 meter distance from the machine surface) when the machine turns at 500 strokes per minute without screenings, viz. the same noise level emitted by an old shuttle loom running at 180-200 strokes/minute. Thanks to the technological development, the weaving speed in the last 20 years has more than doubled, however without increasing the level of acoustic pressure. The attention which most of the industrial countries give today to the issue of environment pollution is more than justified. The noise is not only annoying, but can be harmful to health and at the end increase the social costs.

The EEC guideline Machines 89/392 draws the attention to this problem and invites the manufacturers to design machines in such a way, that the risks due to noise emission are reduced to a minimum, in consideration of the technical progress and of the technical means available to reduce the emissions at their source. This guideline obliges the manufacturers to declare the noise levels emitted by their machines. The noise evaluation of a single weaving machine is anyway not sufficient; in the textile mills dozens, not to say hundreds, work simultaneously in one and the same weaving room and the sound level increases in proportion to the number of looms, even exceeding the threshold of 90 dBa indicated by the present Italian legislation.

The graphics here below show the noise increase in relation to the variation in the intensity of the sound produced by a certain number of sources positioned side by side. You can note that, with 8 noise sources at 89 dBa, the noise level on a central measurement point is equal to 89 dBa; in the case for instance of two noise sources, by increasing the noise level of each source by 5 dBa, we get a variation in the central point of 2 dBa.In the third graphic, if we bring the same noise sources to 90 dBa, we get a central point at a level of 94 dBa. This variation in the value of the central detection point in relation to the change of the sound level of the two noise sources follows a logarithmic trend.

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Technical Textiles in India – A dormant volcano prepares to erupt…


ABSTRACT:-

India is rising and moving ahead with opportunities in every sector. For the past four years India’s GDP has grown up to 8%, and is assumed to remain consistent at 8-9% for coming years. According to Goldman Sachs, India’s economy will exceed the economy of Europe and Japan by 2030 and that of the US by 2045.Such a growth is possible because of the increase in household incomes and the predicted growth in agriculture, manufacturing and service sectors. Also the consumer spending level is growing over 5% per annum which has resulted in the on-going growth of organized retail sectors.

Talking about the technical textile industry in India, it is said to be its initial stage as it contributes only 3% of total consumption. But, it would be wrong to say that India’s technical textile industry is still sleeping. It has woken up to the enormous potential of the technical textile sector and is predicted to grow faster in next two decades than the growth withstand by US and Europe in last three decades. This is said to become possible with the growing middle class, young and educated population. And Technical Textile would be one of the most promising sectors in this growth.

And the factors like, the global economic change, strong government support, the introduction of appropriate legislation, the development of tests and standards, and widespread recognition of the need for more trained personnel, etc. also playing the valuable role in driving the industry to the farthest destination. Thus it won’t be wrong to say that, “Technical Textiles in India- A sleeping volcano prepares to erupt.”

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