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Sunday, March 24, 2013

COTTON FIBRE GROWTH:


COTTON FIBRE GROWTH:
Improvements in cotton fiber properties for textiles depend on changes in the growth and development of the fiber.
Manipulation of fiber perimeter has a potential to impact the length, micronaire, and strength of cotton fibers. The perimeter of the fiber is regulated by biological mechanisms that control the expansion characteristic of the cell wall and establish cell diameter.
mprovements in fiber quality can take many different forms. Changes in length, strength, uniformity, and fineness In one recent analysis, fiber perimeter was shown to be the single quantitative trait of the fiber that affects all other traits . Fiber perimeter is the variable that has the greatest affect on fiber elongation and strength properties. While mature dead fibers have an elliptical morphology, living fibers have a cylindrical morphology during growth and development. Geometrically, perimeter is directly determined by diameter (perimeter = diameter × p). Thus, fiber diameter is the only variable that directly affects perimeter. For this reason, understanding the biological mechanisms that regulate fiber diameter is important for the long-term improvement of cotton.
A review of the literature indicates that many researchers believe diameter is established at fiber initiation and is maintained throughout the duration of fiber development . A few studies have examined, either directly or indirectly, changes in fiber diameter during development. Some studies indicate that diameter remains constant ; while others indicate that fiber diameter increases as the fiber develops.
The first three stages occur while the fiber is alive and actively growing. Fiber initiation involves the initial isodiametric expansion of the epidermal cell above the surface of the ovule. This stage may last only a day or so for each fiber. Because there are several waves of fiber initiation across the surface of the ovule , one may find fiber initials at any time during the first 5 or 6 d post anthesis. The elongation phase encompasses the major expansion growth phase of the fiber. Depending on genotype, this stage may last for several weeks post anthesis. During this stage of development the fiber deposits a thin, expandable primary cell wall composed of a variety of carbohydrate polymers . As the fiber approaches the end of elongation, the major phase of secondary wall synthesis starts. In cotton fiber, the secondary cell wall is composed almost exclusively of cellulose. During this stage, which lasts until the boll opens (50 to 60 d post anthesis), the cell wall becomes progressively thicker and the living protoplast decreases in volume. There is a significant overlap in the timing of the elongation and secondary wall synthesis stages. Thus, fibers are simultaneously elongating and depositing secondary cell wall.
The establishment of fiber diameter is a complex process that is governed, to a certain extent, by the overall mechanism by which fibers expand. The expansion of fiber cells is governed by the same related mechanisms occurring in other walled plant cells. Most cells exhibit diffuse cell growth, in which new wall and membrane materials are added throughout the surface area of the cell. Specialized, highly elongated cells, such as root hairs and pollen tubes, expand via tip synthesis where new wall and membrane materials are added only at a specific location that becomes the growing tip of the cell. While the growth mechanisms for cotton fiber have not been fully documented, recent evidence indicates that throughout the initiation and early elongation phases of development, cotton fiber expands primarily via diffuse growth . Later in fiber development, late in cell elongation, and well into secondary cell wall synthesis (35 d post anthesis), the organization of cellular organelles is consistent with continued diffuse growth . Many cells that expand via diffuse growth exhibit increases in both cell length and diameter; but cells that exhibit tip synthesis do not exhibit increases in cell diameter . If cotton fiber expands by diffuse growth, then it is reasonable to suggest that cell diameter might increase during the cell elongation phase of development.
Cell expansion is also regulated by the extensibility of the cell wall. For this reason, cell expansion most commonly occurs in cells that have only a primary cell wall . Primary cell walls contain low levels of cellulose. Production of the more rigid secondary cell wall usually signals the cessation of cell expansion. Secondary cell wall formation is often indicated by the development of wall birefringence.
Analyses of fiber diameter and cell wall birefringence show that fiber diameter significantly increased as fibers grew and developed secondary cell walls. Both cotton species and all the genotypes tested exhibited similar increases in diameter; however, the specific rates of change differed. Fibers continued to increase in diameter during the secondary wall synthesis stage of development, indicating that the synthesis of secondary cell wall does not coincide with the cessation of cell expansion.

GINNING
The generally recommended machinery sequence at gins for spindle-picked cotton is rock and green-boll trap, feed control, tower drier, cylinder cleaner, stick machine, tower drier, cylinder cleaner, extractor feeder, gin stand, lint cleaner, lint cleaner, and press. 
Cylinder cleaners use rotating spiked drums that open and clean the seedcotton by scrubbing it across a grid-rod or wire mesh screen that allows the trash to sift through. The stick machine utilizes the sling-off action of channel-type saw cylinders to extract foreign matter from the seedcotton by centrifugal force. In addition to feeding seedcotton to the gin stand, the extractor feeder cleans the cotton using the stick machine's sling-off principle. 
In some cases the extractor-feeder is a combination of a cylinder cleaner and an extractor. Sometimes an impact or revolving screen cleaner is used in addition to the second cylinder cleaner. In the impact cleaner, seedcotton is conveyed across a series of revolving, serrated disks instead of the grid-rod or wire mesh screen.
Lint cleaners at gins are mostly of the controlled-batt, saw type. In this cleaner a saw cylinder combs the fibers and extracts trash from the lint cotton by a combination of centrifugal force, scrubbing action between saw cylinder and grid bars, and gravity assisted by an air current 
Seedcotton-type cleaners extract the large trash components from cotton. However, they have only a small influence on the cotton's grade index, visible liint foreign-matter content, and fiber length distribution when compared with the lint cleaning effects. Also, the number of neps created by the entire seedcotton cleaning process is about the same as the increase caused by one saw-cylinder lint cleaner. 
Most cotton gins today use one or two stages of saw-type lint cleaners. The use of too many stages of lint cleaning can reduce the market value of the bale, because the weight loss may offset any gain from grade improvement. Increasing the number of saw lint cleaners at gins, in addition to increasing the nep count and short-fiber content of the raw lint, causes problems at the spinning mill. These show up as more neps in the card web and reduced yarn strength and appearance .
Pima cotton, extra-long-staple cotton, is roller ginned to preserve its length and to minimize neps. To maintain the highest possible quality bale of pima cotton, mill-type lint cleaners were for a long time the predominant cleaner used by the roller-ginning industry. Today, various combinations of impacts, incline, and pneumatic cleaners are used in most roller-ginning plants to increase lint-cleaning capacity. 
COTTON FIBER QUALITY:
Two simple words, fiber quality, mean quite different things to cotton growers and to cotton processors. No after-harvest mechanisms are available to either growers or processors that can improve intrinsic fiber quality. Most cotton production research by physiologists and agronomists has been directed toward improving yields, so the few cultural-input strategies suggested for improving fiber quality during the production season are of limited validity. Thus, producers have limited alternatives in production practices that might result in fibers of acceptable quality and yield without increased production costs. Fiber processors seek to acquire the highest quality cotton at the lowest price, and attempt to meet processing requirements by blending bales with different average fiber properties. Of course, bale averages for fiber properties do not describe the fiber-quality ranges that can occur within the bales or the resulting blends. Further, the natural variability among cotton fibers unpredictably reduces the processing success for blends made up of low-priced, lower-quality fibers and high-priced, higher-quality fibers. Blends that fail to meet processing specifications show marked increases in processing disruptions and product defects that cut into the profits of the yarn and textile manufacturers. Mill owners do not have sufficient knowledge of the role classing-office fiber properties play in determining the outcome of cotton spinning and dyeing processes. Even when a processor is able to make the connection between yarn and fabric defects and increased proportions of low-quality fibers, producers have no way of explaining why the rejected bales failed to meet processing specifications when the bale averages for important fiber properties fell within the acceptable ranges. If, on the other hand, the causes of a processing defect are unknown, neither the producer nor the processor will be able to prevent or avoid that defect in the future. Any future research that is designed to predict, prevent, or avoid low-quality cotton fibers that cause processing defects in yarn and fabric must address the interface between cotton production and cotton processing. Every bale of cotton produced in the USA crosses that interface via the USDA-AMS classing offices, which report bale averages of quantified fiber properties. Indeed, fiber-quality data reports from classing offices are designed as a common quantitative language that can be interpreted and understood by both producers and processors. But the meaning and utility of classing-office reports can vary, depending on the instrument used to evaluate.

Fiber maturity is a composite of factors, including inherent genetic fineness compared with the perimeter or cross section achieved under prevailing growing conditions and the relative fiber cell-wall thickness and the primary -to- secondary fiber cell-wall ratio, and the time elapsed between flowering and boll opening or harvest. While all the above traits are important to varying degrees in determining processing success, none of them appear in classing-office reports.
Micronaire, which is often treated as the fiber maturity measurement in classing-office data, provides an empirical composite of fiber cross section and relative wall thickening. But laydown blends that are based solely on bale-average micronaire will vary greatly in processing properties and outcomes. Cotton physiologists who follow fiber development can discuss fiber chronological maturity in terms of days after floral anthesis. But, they must quantify the corresponding fiber physical maturity as micronaire readings for samples pooled across several plants, because valid micronaire determinations require at least 10 g of individualized fiber.

Some fiber properties, like length and single fiber strength, appear to be simple and easily understood terms. But the bale average length reported by the classing office does not describe the range or variability of fiber lengths that must be handled by the spinning equipment processing each individual fiber from the highly variable fiber population found in that bale. Even when a processing problem can be linked directly to a substandard fiber property, surprisingly little is known about the causes of variability in fiber shape and maturity. For example:
Spinners can see the results of excessive variability in fiber length or strength when manifested as yarn breaks and production halts.Knitters and weavers can see the knots and slubs or holes that reduce the value of fabrics made from defective yarns that were spun from poor-quality fibre
Inspectors of dyed fabrics can see the unacceptable color streaks and specks associated with variations in fiber maturity and the relative dye-uptake success.
The grower, ginner, and buyer can see variations in color or trash content of ginned and baled cotton.
But there are no inspectors or instruments that can see or predict any of the above quality traits of fibers while they are developing in the boll. There is no definitive reference source, model, or database to which a producer can turn for information on how cultural inputs could be adapted to the prevailing growth conditions of soil fertility, water availability, and weather (temperature, for example) to produce higher quality fiber.
The scattered research publications that address fiber quality, usually in conjunction with yield improvement, are confusing because their measurement protocols are not standardized and results are not reported in terms that are meaningful to either producers or processors. Thus, physiological and agronomic studies of fiber quality frequently widen, rather than bridge, the communication gap between cotton producers and processors.
This overview assembles and assesses current literature citations regarding the quantitation of fiber quality and the manner in which irrigation, soil fertility, weather, and cotton genetic potential interact to modulate fiber quality. The ultimate goal is to provide access to the best answers currently available to the question of what causes the annual and regional fiber quality variations 
From the physiologist's perspective, the fiber quality of a specific cotton genotype is a composite of fiber shape and maturity properties that depend on complex interactions among the genetics and physiology of the plants producing the fibers and the growth environment prevailing during the cotton production season.
Fiber shape properties, particularly length and diameter, are largely dependent on genetics. Fiber maturity properties, which are dependent on deposition of photosynthate in the fiber cell wall, are more sensitive to changes in the growth environment. The effects of the growth environment on the genetic potential of a genotype modulate both shape and maturity properties to varying degrees.
Anatomically, a cotton fiber is a seed hair, a single hyperelongated cell arising from the protodermal cells of the outer integument layer of the seed coat. Like all living plant cells, developing cotton fibers respond individually to fluctuations in the macro- and microenvironments. Thus, the fibers on a single seed constitute continua of fiber length, shape, cell-wall thickness, and physical maturity .
Environmental variations within the plant canopy, among the individual plants, and within and among fields ensure that the fiber population in each boll, indeed on each seed, encompasses a broad range of fiber properties and that every bale of cotton contains a highly variable population of fibers.
Successful processing of cotton lint depends on appropriate management during and after harvest of those highly variable fiber properties that have been shown to affect finished-product quality and manufacturing efficiency . If fiber-blending strategies and subsequent spinning and dyeing processes are to be optimized for specific end-uses and profitability, production managers in textile mills need accurate and effective descriptive and predictive quantitative measures of both the means and the ranges of these highly variable fiber properties .
In the USA, the components of cotton fiber quality are usually defined as those properties reported for every bale by the classing offices of the USDA-AMS, which currently include length, length uniformity index, strength, micronaire, color as reflectance (Rd) and yellowness (+b), and trash content, all quantified by the High Volume Instrument (HVI) line. The classing offices also provide each bale with the more qualitative classers' color and leaf grades and with estimates of preparation (degree of roughness of ginned lint) and content of extraneous matter.
The naturally wide variations in fiber quality, in combination with differences in end-use requirements, result in significant variability in the value of the cotton lint to the processor. Therefore, a system of premiums and discounts has been established to denote a specified base quality. In general, cotton fiber value increases as the bulk-averaged fibers increase in whiteness (+Rd), length, strength, and micronaire; and discounts are made for both low mike (micronaire less than 3.5) and high mike (micronaire more than 4.9). 
Ideal fiber-quality specifications favored by processors traditionally have been summarized thusly: "as white as snow, as long as wool, as strong as steel, as fine as silk, and as cheap as hell." These specifications are extremely difficult to incorporate into a breeding program or to set as goals for cotton producers. Fiber-classing technologies in use and being tested allow quantitation of fiber properties, improvement of standards for end-product quality, and, perhaps most importantly, creation of a fiber-quality language and system of fiber-quality measurements that can be meaningful and useful to producers and processors alike.GENE AND ENVIRONMENTAL VARIABILITY:
Improvements in textile processing, particularly advances in spinning technology, have led to increased emphasis on breeding cotton for both improved yield and improved fiber properties Studies of gene action suggest that, within upland cotton genotypes there is little non-additive gene action in fiber length, strength, and fineness ; that is, genes determine those fiber properties. However, large interactions between combined annual environmental factors (primarily weather) and fiber strength suggest that environmental variability can prevent full realization of the fiber-quality potential of a cotton genotype. More recently, statistical comparisons of the relative genetic and environmental influences upon fiber strength suggest that fiber strength is determined by a few major genes, rather than by variations in the growth environment . Indeed, spatial variations of single fertility factors in the edaphic environment were found to be unrelated to fiber strength and only weakly correlated with fiber length .
Genetic potential of a specific genotype is defined as the level of fiber yield or quality that could be attained under optimal growing conditions. The degree to which genetic potential is realized changes in response to environmental fluctuations such as application of water or fertilizer and the inevitable seasonal shifts such as temperature, day length, and insolation.In addition to environment-related modulations of fiber quality at the crop and whole-plant levels, significant differences in fiber properties also can be traced to variations among the shapes and maturities of fibers on a single seed and, consequently, within a given boll.
EFFECT ON FIBER LENGTH:
Comparisons of the fiber-length arrays from different regions on a single seed have revealed that markedly different patterns in fiber length can be found in the micropylar, middle, and chalazal regions of a cotton seed - at either end and around the middle . Mean fiber lengths were shortest at the micropylar (upper, pointed end of the seed) . The most mature fibers and the fibers having the largest perimeters also were found in the micropylar region of the seed. After hand ginning, the percentage of short fibers less than 0.5 inch or 12.7 mm long on a cotton seed was extremely low.
It has been reported that, in ginned and baled cotton, the short fibers with small perimeters did not originate in the micropylar region of the seed . MEasurements of fibers from micropylar and chalazal regions of seeds revealed that the location of a seed within the boll was related to the magnitude of the differences in the properties of fibers from the micropylar and chalazal regions. Significant variations in fiber maturity also can be related to the seed position (apical, medial, or due to the variability inherent in cotton fiber, there is no absolute value for fiber length within a genotype or within a test sample . Even on a single seed, fiber lengths vary significantly because the longer fibers occur at the chalazal (cup-shaped, lower) end of the seed and the shorter fibers are found at the micropylar (pointed) end. Coefficients of fiber-length variation, which also vary significantly from sample to sample, are on the order of 40% for upland cotton. Variations in fiber length attributable to genotype and fiber location on the seed are modulated by factors in the micro- and macroenvironment . Environmental changes occurring around the time of floral anthesis may limit fiber initiation or retard the onset of fiber elongation. Suboptimal environmental conditions during the fiber elongation phase may decrease the rate of elongation or shorten the elongation period so that the genotypic potential for fiber length is not fully realized . Further, the results of environmental stresses and the corresponding physiological responses to the growth environment may become evident at a stage in fiber development that is offset in time from the occurrence of the stressful conditions. Fiber lengths on individual seeds can be determined while the fibers are still attached to the seed , by hand stapling or by photoelectric measurement after ginning. Traditionally, staple lengths have been measured and reported to the nearest 32nd of an inch or to the nearest millimeter. The four upland staple classes are: short (<21>34 mm). Additionally, short fiber content is defined as the percentage of fiber less than 12.7 mm.
Cotton buyers and processors used the term staple length long before development of quantitative methods for measuring fiber properties. Consequently, staple length has never been formally defined in terms of a statistically valid length distribution. In Fibrograph testing, fibers are randomly caught on combs, and the beard formed by the captured fibers is scanned photoelectrically from base to tip . The amount of light passing through the beard is a measure of the number of fibers that extend various distances from the combs. Data are recorded as span length (the distance spanned by a specific percentage of fibers in the test beard). Span lengths are usually reported as 2.5 and 50%. The 2.5% span length is the basis for machine settings at various stages during fiber processing.
The uniformity ratio is the ratio between the two span lengths expressed as a percentage of the longer length. The Fibrograph provides a relatively fast method for reproducibility in measuring the length and length uniformity of fiber samples. Fibrograph test data are used in research studies, in qualitative surveys such as those checking commercial staple-length classifications, and in assembling cotton bales into uniform lots. Since 1980, USDA-AMS classing offices have relied almost entirely on high-volume instrumentation (HVI) for measuring fiber length and other fiber properties (Moore, 1996). The HVI length analyzer determines length parameters by photoelectrically scanning a test beard that is selected by a specimen loader and prepared by a comber/brusher attachment
The fibers in the test beard are assumed to be uniform in cross-section, but this is a false assumption because the cross section of each individual fiber in the beard varies significantly from tip to tip. The HVI fiber-length data are converted into the percentage of the total number of fibers present at each length value and into other length parameters, such as mean length, upper-half mean length, and length uniformity . This test method for determining cotton fiber length is considered acceptable for testing commercial shipments when the testing services use the same reference standard cotton samples.
All fiber-length methods discussed above require a minimum of 5 g of ginned fibers and were developed for rapid classing of relatively large, bulk fiber samples. For analyses of small fiber samples , fiber property measurements with an electron-optical particle-sizer, the Zellweger Uster AFIS-A2 have been found to be acceptably sensitive, rapid, and reproducible. The AFIS-A2 Length and Diameter module generates values for mean fiber length by weight and mean fiber length by number, fiber length histograms, and values for upper quartile length, and for short-fiber contents by weight and by number (the percentages of fibers shorter than 12.7 mm). The AFIS-A2 Length and Diameter module also quantifies mean fiber diameter by number .
Although short-fiber content is not currently included in official USDA-AMS classing office reports, short-fiber content is increasingly recognized as a fiber property comparable in importance to fiber fineness, strength, and length . The importance of short-fiber content in determining fiber-processing success, yarn properties, and fabric performance has led the post-harvest sector of the U.S. cotton industry to assign top priority to minimizing short-fiber content, whatever the causes . The perceived importance of short-fiber content to processors has led to increased demands for development and approval of a standard short-fiber content measurement that would be added to classing office HVI systems . This accepted classing office-measurement would allow inclusion of short-fiber content in the cotton valuation system. Documentation of post-ginning short-fiber content at the bale level is expected to reduce the cost of textile processing and to increase the value of the raw fiber . However, modulation of short-fiber content before harvest cannot be accomplished until the causes of increased short-fiber content are better understood.
Fiber length is primarily a genetic trait, but short-fiber content is dependent upon genotype, growing conditions, and harvesting, ginning, and processing methods. Further, little is known about the levels or sources of pre-harvest short-fiber content . 
It is essential that geneticists and physiologists understand the underlying concepts and the practical limitations of the methods for measuring fiber length and short-fiber content so that the strong genetic component in fiber length can be separated from environmental components introduced by excessive temperatures and water or nutrient deficiencies. Genetic improvement of fiber length is fruitless if the responses of the new genotypes to the growth environment prevent full realization of the enhanced genetic potential or if the fibers produced by the new genotypes break more easily during harvesting or processing. The reported effects of several environmental factors on fiber length and short-fiber content, which are assumed to be primarily genotype-dependent, are discussed in the subsections that follow.FIBER LENGTH AND TEMPERATURE:
Maximum cotton fiber lengths were reached when night temperatures were around 19 to 20 °C, depending on the genotype . Early-stage fiber elongation was highly temperature dependent; late fiber elongation was temperature independent . Fiber length (upper-half mean length) was negatively correlated with the difference between maximum and minimum temperature.
Modifications of fiber length by growth temperatures also have been observed in planting-date studies in which the later planting dates were associated with small increases in 2.5 and 50% span lengths . If the growing season is long enough and other inhibitory factors do not interfere with fiber development, early-season delays in fiber initiation and elongation may be counteracted by an extension of the elongation period .
Variations in fiber length and the elongation period also were associated with relative heat-unit accumulations. Regression analyses showed that genotypes that produced longer fibers were more responsive to heat-unit accumulation levels than were genotypes that produced shorter fibers . However, the earliness of the genotype was also a factor in the relationship between fiber length (and short-fiber content by weight) and accumulated heat units . 
As temperature increased, the number of small motes per boll also increased. Fertilization efficiency, which was negatively correlated with small-mote frequency, also decreased. Although fiber length did not change significantly with increasing temperature, the percentage of short-fibers was lower when temperatures were higher. The apparent improvement in fiber length uniformity may be related to increased assimilate availability to the fibers because there were fewer seeds per boll.FIBER LENGTH AND WATER:
Cotton water relationships and irrigation traditionally have been studied with respect to yield . Fiber length was not affected unless the water deficit was great enough to lower the yield to 700 kg ha-1. Fiber elongation was inhibited when the midday water potential was -2.5 to -2.8 mPa. Occurrence of moisture deficits during the early flowering period did not alter fiber length. However, when drought occurred later in the flowering period, fiber length was decreased .
Severe water deficits during the fiber elongation stage reduce fiber length , apparently due simply to the direct mechanical and physiological processes of cell expansion. However, water availability and the duration and timing of flowering and boll set can result in complex physiological interactions between water deficits and fiber properties including length.
FIBRE LENGTH AND LIGHT:
Changes in the growth environment also alter canopy structure and the photon flux environment within the canopy. For example, loss of leaves and bolls from unfavorable weather (wind, hail), disease, or herbivory and compensatory regrowth can greatly affect both fiber yield and quality . The amount of light within the crop canopy is an important determinant of photosynthetic activity and, therefore, of the source-to-sink relationships that allocate photoassimilate within the canopy . Eaton and Ergle (1954) observed that reduced-light treatments increased fiber length. Shading during the first 7 d after floral anthesis resulted in a 2% increase in the 2.5% span length .
Shading (or prolonged periods of cloudy weather) and seasonal shifts in day length also modulate temperature, which modifies fiber properties, including length.
Commercial cotton genotypes are considered to be day-length neutral with respect to both flowering and fruiting . However, incorporation of day-length data in upland and pima fiber-quality models, based on accumulated heat units, increased the coefficients of determination for the length predictors from 30 to 54% for the upland model and from 44 to 57% for the pima model .
It was found that the light wavelengths reflected from red and green mulches increased fiber length, even though plants grown under those mulches received less reflected photosynthetic flux than did plants grown with white mulches. The longest fiber was harvested from plants that received the highest far red/red ratios.



An overview on some of the basics of TQM

TQM is the art of managing all the activities of an organization to achieve excellence. It is a philosophy and a set of guiding principles that represent the foundation of a continuously improving organization, wherein the application of quantitative methods and human recourses are sought to improve all the processes within the organization so as to meet and exceed the customer needs now and continuously with change of time. It is a proven technique to ensure survival in the era of globalization of trade. TQM can be defined as an integrated organizational approach in delighting customers (Both Internal and External) by meeting their expectations on a continuous basis through everyone involved with organization working on continuous improvement in all products, services and processes along with proper problem solving methodology.
Quality definition and its dimensions
The expression Quality has to be understood clearly from the customer point of view for the success of TQM Programme. One usually thinks about Quality in terms of an excellent product or service that fulfills or exceeds the expectations. These expectations are based on the intended use and the selling prize. If a product or service surpasses the expectations one relate it with the quality. Thus it is more or less an intangible thing based on perception. The Quality can be quantified as follows:
Q = (P / E),
Where, Q- Quality, P- Performance and E- Expectations
If Q is greater than 1 then the customer has a good feeling about the product or service. It should be noted that based on perception P is determined by the organization and E determined by the customer.
As per ISO 9000:2000, quality is defined as the degree to which a set of inherent characteristics fulfill requirements. Degree means that quality can be used with adjectives such as poor, good and excellent. Inherent is defined as existing in something, especially as a permanent characteristic. Characteristics can be quantitative or qualitative. Requirement is a need or expectation that is stated; generally implied by the organization, its customers and other interested parties; or obligatory. Quality has different dimensions as mentioned below:
Quality Dimension
Explanation1. PerformancePrimary Product Characteristics2. Features
Secondary Product Characteristics
3. Conformance
Meeting specification/ Standards/ Workmanship4. Reliability
Consistency of Performance over the Time
5. DurabilityUseful Life
6. ServiceResolution of Problems and Complaints
7. ResponseHuman-to-human Interface
8. Aesthetics
Sensory Characteristics
9. Reputation
Past PerformanceTQM is an approach to management that can be characterized by its principles, practices, and techniques and emphasized on customer focus, continuous improvement, and teamwork.
Basic Principles and Concepts of TQM:
The TQM programme is a continual activity that must be entrenched as culture and requires the following six basics principles and concepts knitted by effective communication:
Top management Commitment- Leadership
Focus on customer- Customer Satisfaction
Effective involvement and utilization of entire employee
Continuous improvement
Treating suppliers as partners
Establishing performance measures for the processes

Top management Commitment:
Top management participation and complete involvement is essential in the total quality programme. The management commitment should be clearly visible through their acts and deeds. A Quality Council must be established to develop a clear vision, set long term goals and direct the quality programme. The short and long term business plan shall include the quality goals. An annual quality improvement programme is to be established on the basis of Collection of inputs from every stakeholders of business. Managers also get involved in quality improvement teams and provide leadership. Leadership is essential during every phase of the implementation process and particularly at the start.
Leadership
There is no universal definition of leadership. A leader strengthens and inspires the followers to accomplish shared goals. Leaders shape the organizations values and promote, protect and exemplify it.
An organizations seniors leaders should set directions and create a customer focus, clear and visible values, and high expectations. The directions, values and expectations should balance the needs of all the stakeholders. The leaders should ensure the creation of strategies, systems and methods for achieving excellence, stimulating innovation and building knowledge and capabilities. The values and strategies should help in guiding all activities and decisions of the organization. Senior leaders should inspire, motivate and encourage all employees to contribute, to develop and learn, to be innovative and to creative.
Seniors leaders should serve as role models through their ethical behaviour and their personal involvement in planning, in communications, coaching, development of future leaders, review of organizational performance and employee recognition. As role models, they can reinforce values and expectations while building leadership, commitment, and initiative throughout the organization.
Characteristics of quality leadersLeadership can be difficult to define. However, successful quality leaders tend to have certain characteristics. There are many characteristics that successful quality leaders demonstrate.
Priority attention to external and internal customers and their need
Empower, rather than control, subordinates.
Emphasize improvement rather than maintenance.
Importance to prevention.
Encourage collaboration rather than competition.
Train and coach rather than direct and supervise.
Learn from problems.
Continually try to improve communications.
Continually demonstrate their commitment to quality.
Select suppliers on the basis of quality, not price.
Establish organizational systems to support the quality effort
Encourage and recognize team effort.
Seven Habits of Highly effective People
Stephen R. Covey found the following seven habits of Highly Effective People. A habit is the intersection of knowledge, skill and desire. Knowledge is what to do and Why; skill is the how to do; and desire is the motivation or want to do. In order for something to become a habit we have to have all the three.
1. Be proactive
2. Begin with the end in mind
3. Put first thing first
4. Think win-win
5. Seek first to understand, then to be understood
6. Synergy
7. Sharpen the saw ( Renewal)

The seven habits are a highly integrated approach that moves from dependency (you take care of me) to independence (I take care of myself) and to interdependence (we can do something better together). The first three habits deal with independence-the essence of character growth. The habits 4, 5 and 6 are dealing with interdependenceteamwork, cooperation, and communication. Habit 7 is the habit of renewal. The seven habits are in harmony with a natural law that Covey calls the P/PC Balance, where P stands for Production of desired result and PC stand for Production Capacity, the ability or asset.
Focus on customer - Customer Satisfaction:
The key to effective TQM Programme is to focus on Internal/ external customer needs and satisfaction. The organization should listen to the voice of the customer and give greater importance to the customer perception and satisfaction.
Manufacturing and service organization are using customer satisfaction as the measure of quality. The Total quality management implies an organizational obsession with meeting or exceeding customer expectations, so that customer is delighted. Understanding the customers needs and expectations is essential to win new business and retain the existing one. An organization must give its customers a quality product or service that meets their needs at a reasonable price, which include on-time delivery and out standing service. To attain these levels, the organization needs to continually examine their quality system to see if it is responsive to ever-changing customer requirements and expectations.
Customer perception of Quality
The most successful TQM programs begin by defining quality from the customers perspective. An American Society for Quality survey on end user perceptions of important factors that influence purchases showed the following ranking
1. Performance
2. Features
3. Service
4. Warranty
5. Price
6. Reputations
The factors such as Performance, Features, Service and Warranty are part of the product or service quality; therefore it is evident that product quality and service is more important than price.
Using Customer Feedback
Customer feedback must be continually solicited and monitored. It is not a one time effort; it is an ongoing and active probing of the customer mind. Feed back enable the organization to
* Discover customer dissatisfaction
* Discover relative priorities of quality
* Compare performance with the competition
* Identify Customers need.
* Determine opportunity for improvement
Using Customer ComplaintFeedback is proactive and the complaints are reactive in nature. Even then they are very vital in gathering data on customer perceptions. A dissatisfied customer can easily become a lost customer. Many organization uses customer dissatisfaction as the primary measures to assess their process improvement effort. A positive approach towards complaint creates opportunity to obtain information and a better service level can be assured.

Service Quality
Customer service is the set of activities an organization uses to win and retain customers satisfaction. It can be provided before, during, or after the sale of product. Following are the dimensions of service quality.
1. Tangibles- physical evidence of service
2. Reliability- Consistency in providing the service
3. Responsiveness - Readiness and Willingness of the employees
4. Assurance Ability of employee to convey trust and confidence
5. The ability of the employees to put themselves in the customer shoes
Customer retention
Customer retention is more powerful and effective than customer satisfaction. Customer retention represents the activities that produce the necessary customer satisfaction that creates customer loyalty, which actually improves the bottom line.
Effective involvement and utilization of entire employee
As the TQM is the organization wide challenge, every employees involvement is essential. All personnel must be must be trained in TQM, Statistical Process Control and other appropriate quality improvement skills so that they can effectively participate in the quality teams.
Motivation
Motivation means a process of stimulating people to accomplish desired goals. Motivation could be explained in terms of hierarchy of need and that there were five levels as explained by Abraham Maslow. These levels are survival, security, social, esteem and self-actualization. Frederick Herzberg found that people were motivated by recognition, responsibility, achievement, advancement and the work itself. While management thinks that good pay is the number one need of the employee. Survey results show that this factor is usually in the middle of the ranking. Employee tends to follow the theories of Maslow and Herzberg. By involving employees through the use of teams in meaningful work and by providing the proper reward and recognition, mangers can reap the advantages of greater quality and productivity along with employee satisfaction.
Empowerment
Empowerment is an environment in which people have the ability, the confidence and the commitment to take the responsibility and ownership to improve the process and initiate the necessary step to satisfy customer requirement within well defined boundaries in order to achieve organizational values and goals. Employee empowerment requires that the individual is held responsible for accomplishing whole task. The employee becomes the process owner- thus the individual is not only responsible but also accountable. In order to create empowered environment three conditions are necessary.
* Every one must understand the need for change
* The system needs to change to the new paradigm
* The organization must enable its employee


Teams
Employee involvement is optimized by the use team. In most instances they are effective because many heads are more knowledgeable than one. Each members of the team has special abilities that can be used to solve complex problems. The interactions within the team produce the results that exceed the contributions of each member. There are various types of teams, namely Process improvement team, cross-functional team, natural work team, self-directed team. But people need to be trained to work as a team. There are mainly three types of teams that TQM organizations adopt:
A. Quality Improvement Teams or Excellence Teams (QITS) - These are temporary teams with the purpose of dealing with specific problems that often re-occur. These teams are set up for period of three to twelve months.
B. Problem Solving Teams (PSTs) - These are temporary teams to solve certain problems and also to identify and overcome causes of problems. They generally last from one week to three months.
C. Natural Work Teams (NWTs) - These teams consist of small groups of skilled workers who share tasks and responsibilities. These teams use concepts such as employee involvement teams, self-managing teams and quality circles. These teams generally work for one to two hours a week.
Recognition and Reward
Recognition is a form of employee motivation in which the organization acknowledges the positive contributions an individual or team has made to the success of the organization. Reward is something tangible. Recognition and reward go together to form a system for letting people know that they are valuable members of the organization. As people are recognized, there can be huge changes in self-esteem, productivity, quality and the amount of effort exhorted to the task at hand. Recognition comes in its best form when it is immediately following an action that an employee has performed. Recognition comes in different ways, places and time such as,
Ways - It can be by way of personal letter from top management. Also by award banquets, plaques, trophies etc.
Places - Good performers can be recognized in front of departments, on performance boards and also in front of top management.
Time - Recognition can be given at any time like in staff meeting, annual award banquets, etc.
Performance appraisalThe purpose of performance appraisal is to let employees know how they are doing and provide a basis for promotions, salary increase, counseling and other purposes related to an employees future. Performance appraisal may be for the team or individuals. Regardless of the system a key factor in a successful performance appraisal is employee involvement.
Continuous improvementsThere must be a continual striving to improve all business and production processes. Quality improvement projects, such as on-time delivery, customer satisfaction, waste reduction, product realization and inventory are good places to begin Tools. Thus, techniques such as Juran Trilogy, PDSA Cycle, 5S, Benchmarking, Quality function deployment, TQC, Kaizen etc. are excellent for problem solving at various activities.
Treating suppliers as partners
As the significant quantity of business activity is the purchased product or service, their performance quality is contributing lot to the companys quality. Therefore partnership relationship with suppliers must be developed. Both parties have as much gain or lose based on the success or failure of the product or service. Focus should be on quality and life cycle costs rather than price.

Establishing performance measures for the processes
For each functional area performance measures should be determined and posted for everyone to see. Quantitative data are necessary to measure the continuous quality improvement activity.
The purpose of TQM is to provide a quality product and/or Service to customers, which will, in turn, increase productivity and lower cost. With a higher quality product and lower price, competitive position in the marketplace will be enhanced. This series of events will allow the organization to achieve the objectives of profit and growth with greater ease. In addition, the work force will have job security, which shall create a satisfying place to work.
The TQM require a cultural change and this change being substantial can not be accomplished in short period of time. The following changes are expected due to TQM implementation

Elements Before TQM Implementation After TQM implementation
Definition Product oriented Customer oriented
Priorities Second to Service and cost First among equals of service and cost
Decisions Short term Long-term
Emphasis Detection Prevention
Errors Operations System
Responsibility Quality Control Everyone
Problem solving Managers Teams
Procurement Price Life-cycle costs, Partnership
Managers Role Plan, assign, Control and enforce Delegate, coach, facilitate and mentors
Communication
It is a vital link between all elements of TQM. Communication means a common understanding of ideas between the sender and the receiver. The success of TQM demands communication with and among all the organization members, suppliers and customers. Supervisors must keep open airways where employees can send and receive information about the TQM process. Communication coupled with the sharing of correct information is vital. For communication to be credible the message must be clear and receiver must interpret in the way the sender intended.
Downward communication
This is the dominant form of communication in an organization. Presentations and discussions basically do it. Supervisors are able to make the employees aware about the basic features of total quality management and its importance.
Upward communicationBy this the lower level of employees are able to provide suggestions to upper management of the affects of TQM. As employees provide insight and constructive criticism, supervisors must listen effectively to correct the situation that comes about through the use of TQM. This forms a level of trust between supervisors and employees. This is also similar to empowering communication
, where supervisors keep open ears and listen to others.

Sideways communication
This type of communication is important because it breaks down barriers between departments. It also allows dealing with customers and suppliers in a more professional manner.
References:
Dale H Besterfield et al, Total Quality Management, Pearson Education.
Stephen R. Covey et al, First Thing First, Simon & Schuster.
V. Jayakumar et al, Total Quality Management, Lakshmi Publications.
Besterfiled, Dale H., Quality control, Prentice Hall.
Bossert, James L., Quality Function Deployment: A Practioners Approach, ASQ Quality Press.
Camp, Robert C., Bench Marking: The Search for Industry Best Practices that Lead to Superior Practice, ASQ Quality Press.

New developments in spinning, weaving, & processing
The textile industry has been developing rapidly and newer technologies are introduced and the only formula for survival is encapsulating those innovations into the manufacturing process and making the best of use them for increasing the productivity and quality, says Chitra Siva Sankar.

Textile industry is a traditional and a very old industry, and has been amidst almost all kinds of culture around the world from the very beginning, which almost proves the point that the history of human culture and the textiles, are the same. A wide spectrum of processes is involved in the textile industry. Starting from fibre manufacturing to the final processing and garmenting stage, involves a lot of technologies and skills, which leads to a quality conversion of fibres into the ultra modern fashion or a high performance commodity in the case of technical textiles.

The first major change in the textile industry took place somewhere during the industrial revolution which lead to the advent of the machines in to the manufacturing processes in the textile industry. This major breakthrough lead to reduction in the work load of the labours and pronounced the dawn of machines in the textile industry. After that there have been a lot of developments in the various sectors of the textile industry, and the following would throw light on the latest developments that have taken place in the major segments of textile industry, namely spinning, weaving, knitting and processing.

Spinning
Spinning is the industry, which provides raw material for the knitting and weaving industry. The main driving factor of the companies today is to achieve and improve yarn quality that will ensure better competitiveness and higher yarn prices. The developments that are coming up in the industry today are mainly for maintaining higher productivity with effective quality control, by selecting suitable equipment and spinning conditions to match with the raw materials. One of the very important concepts that has revolutionised the spinning industry is the compact spinning concept. After the advent of the compact spinning, yarn quality parameter has changed, especially in respect to yarn hairiness, strength and to some extent imperfections. The compact spinning system has been designed to meet the challenges faced by the high-end spinning mills.
• Optimum and sustained yarn quality.
• High consistency of all yarn parameters.
• Minimal variations between spinning positions.
• Easy handling.
• Raw material cost saving.
• Increased production.

Compact spinning attachment can be accommodated on the existing machine types. Some advantages of the compact spinning system (EliTe®CompactSet V5):
Yarn
o Tenacity increases by 25%.
o Zweigle (S85) hairiness (fibres exceeding 3 mm) reduced by 3% and Uster (H) Hairiness reduced by up to 30%.
o Elongation increased by 15% to 20%.
o Work capacity increased by up to 50%.
o Improvement in yarn irregularity.
•Spinning 
o Optimum utilisation of fibre substance.
o Improved spinning stability.
o Ends-down rate reduced by up to 60%.
o Fibre loss reduced up to 0.01%.
o Fibre fly reduction in the spinning room.
o Possibility of reducing the twist by 10% and corresponding increase in the production.
Other players in the compact spinning system are Toyota Way, Zinser, RocoS.
Weaving
The most innovative developments, which have taken place in the field of weaving machinery, have changed the weaving sector completely. The weaving sector was said to be labour intensive in the past but now because of the advent of the shuttleless weaving technologies and other innovations, the scenario is changed, and now it is capital intensive. The shuttleless technologies have many advantages over the conventional weaving systems.

• Excellent quality fabrics with high productivity.
• Versatility, consistency and reliability of the machines.
• Better fabric engineering and creative weave patterns possible.
It is not just the three major concepts; Rapier, Air-jet and Projectile, but also a new one in the race, ‘Multiphase Weaving Concept’. Several features are common for the three weaving systems. All of these possess;
• Electronic monitoring and control systems, which increases the quality of the fabric and productivity.
• Cam, dobby and jacquard shedding systems can be used.
• Quick style change mechanism, which reduces downtime.
• Use of weft accumulators which almost provide a tension free weft insertion.
• Low vibrations due to rigid and sturdy frames.

When considering the multiphase weaving concept, the buzz name in the weaving industry is the Sulzer. Sulzer Ruti’ M8300. There is a warp-wise shed formation in this instead of weft-wise shed formation as found in the other weaving systems. One can insert four weft yarns simultaneously at a constant uniform yarn velocity of 22 m/s with minimal weft loading. One can go up to a maximum of 5,500 m/min of weft insertion rate, which is several times higher than that of the other single phase weaving systems.

There are several advantages of the multiphase weaving concept over the single phase technologies:
• Minimum specific energy consumption.
• Small footprint.
• Reduced room air treatment requirement and less dust production (made possible by the integrated dust extraction system and air conditioning system).
• Substantially lower noise emissions.
• 20 to 30 per cent lower production costs.
Knitting
Knitting is the process of looping and inter-looping or inter-meshing the loops to form a fabric. Knitting by hand is an ancient art whose actual origin is not clearly known. The advent of knitting machines enhanced the speed of production and different designs. Knitting is becoming more and more popular because of the low cost of production and also of its single stage ornamentation. There are two main kinds of knitting; One is weft knitting and the second is warp knitting. The following throws light on the developments that have taken place in the weft-knitting sector.

Creel unit
The main concern in the creel unit is the fly removal. The fly removal system, mounted at one end of the creel removes the fly, which affects the quality, which also when arising in large quantity jams the entire running of the machine. A tube is provided starting from the yarn-mounting place the wheel that feeds the threads in the formation of the cloth. This way the production quality does not deteriorate. The air is compressed for threading, and the material is bit polished, which offers very less friction that maintains thread quality.

Yarn feeder
The yarn feeder pulls out the yarn from the package and adjusts it, so that the needles are placed with uniform tension for knitting. This is the only job the yarn feeder does. It is very essential that the tension is maintained uniformly, as the length of yarn per stitch has to be unique for the whole length of the cloth. The machine has attained super efficiency with its improved feed wheel and the tensioner. The present day’s super-positive feed wheel with yarn tensioner, with a motion stopper, along with multiple looping has increased efficiency. Less or nil amount of slippage helps the cloth quality to upgrade. Latest positive feeders for circular knitting are easy to navigate, needs less maintenance and are quite durable. The whole unit is housed with a plastic cover, and is very light in weight, results in less vibration and elimination of static charge.

Some of the machines have electronic controls with enhance yarn feed process. Materials used in the spooler are always being researched so that filamentation is less in amount. The coating is hard to resist corrosion and wearing off. A clutch is provided with open-design, which is helpful while cleaning. The ceramic yarn guide prevents short-circuiting of the vibration tensioner that contains magnetic rings. All these mechanisms are to ensure perfect tension. For irregular or intermittent feed the yarn feeders have to stop periodically in between the weave as in case of the jacquard machine. All these specifications have been achieved in the storage yarn feed, developed by IRO.

Cams and needles
The heart of the knitting machine is the cams and needles. The machine efficiency looks after design and the quality of fabrication. The cam and the needle, which have been arranged as the cylinder and the dial move in unison to move the needle which makes them involved with the knitting process in more direct manner. The backup system ensures that there are almost double knitting arrangements. It makes knitting a no-trouble operation. Cam boxes that have been manufactured by Amtek, using high strength alloys, are good conductors of heat, which implies that heat is removed promptly from the system.

The needles that weave smooth patterns are very delicate in nature that can withstand certain amount of tension but not much. Designing is very important part, so that the needles work for longer. Various parameters for the making of needles to resist different fabrics are: Modern improved surface quality, head geometry, heat treatment and shape of the shank. With circular stitching styles, the bending of the needles is the main problem. The needle hooks are made circular for this kind of stitching. To increase efficiency of the needle without compromising the space for the yarn, designers have devised the cone-shaped needle hooks. The shank design holding three needles have been improved geometrically to take care of the machine vibration. A needle with special latch and extra saw slot for smooth operation with rest surface at the back of the latch, was designed by Groz Beckert who has been manufacturing needles for years. At the end of the latch there is a spring that helps regulating the tension.

Sinkers
The sliding movement provided by the sinker supports the loop. The curves have been properly designed and there is surface finish. The yarn tension is reduced with this design.

Take-down
The tension has to be almost the same everywhere throughout the circumference of the unit. There is an open-width fabric cutter and take-up with black-and-white Lycra wheels appearing gray as long as the fabric is running and clear black and white when the yarn breaks. This helps in enhancing fabric take-down performance. The centre puncturing of the roll is ceased, and the calculation is done with EPA for even take down and rolling of yarn for without a crunch for the entire width of the fabric.
Apart from the technological developments on the machine, there have been developments in the case of patter designing also. Other developments which has to be mentioned here are the Mayer and Cie’ Relanit technology. For faster change in fine gauge machines, open width take down with quality has been developed by Terrot. Four track feeders for every cam box instead of the three track feeders have been introduced by Santoni, which helps in easy cam replacement.

ProcessingTextile processing industry is one of the largest industrial users of process water and huge quantities of complex chemicals that are used in different stages of processing. There have been a lot environmental concerns for the processing sector in the last few years. Hence the wet processing industry of the future should be cost effective, environmental-friendly and also very gentle to the textile materials. The following will throw light on a very innovative environmental-friendly concept of dyeing, supercritical carbon dioxide dyeing.

Supercritical carbon dioxide has been tried in different areas of textile treatments and has very high potential because this dyeing medium completely avoids water pollution and use of conventional auxiliaries in dyeing as well as after treatments. The drying after dyeing is also not required. The CO2 dyeing technology is now on its way to become an industrial application. Hence, it is a new technologically profitable process.

Supercritical fluid
Supercritical fluids are advantages in textile processing as they combine the valuable properties of both gas and liquid. The solvating power of supercritical fluid is proportional to its density, whereas its viscosity is comparable to that of a normal gas. Such a combination leads to highly remarkable penetration properties. The increased power of solvation with the increase in density is desirable in the dyeing process as it has a decisive effect on the dissolution of disperse dye in the supercritical carbon dioxide medium. The following is the phase diagram for CO2.

Further increases in pressure, for example, will greatly increase the dielectric constant of such system, thus imparting dissolving powers even to a system that under normal condition of p and T has almost none.

Reasons for selecting CO2
Carbon dioxide is the best choice. It is non-toxic; It is used in the food and beverage industry; It is inflammable; It is supplied in large amounts either from combustion processes or volcanic sources without the need of producing new gas and it can be recycled in a closed system. Carbon dioxide is frequently used as a solvent because of its special and unique properties;
• Virtually inexhaustible resources (atmosphere, combustion processes, natural geologic deposits).
• Since carbon dioxide is a constituent of natural metabolic processes occurring in the biosphere it is consumed by assimilation and is returned to the natural circuit by dissimilation. It is not only biodegradable as nutrient promoting the growth of plants, but is an essential element of natural processes.
• Carbon dioxide does not affect the edibility of foodstuffs and will only have toxic effects at extremely high concentrations.
• It is produced on the commercial scale and is readily available together with the necessary logistics.

Concepts for dyeing equipment using supercritical fluids
The machine is an extraction plant modified for processing with the supercritical fluids. In contrast to conventional extraction plants the dyestuff are applied to the substrate instead of being removed, ie, the fluid will have to be loaded with dyestuff prior to coming in contact with the goods to be dyed. This can be done in two manners;

1. The dyestuff is filled into the pressure vessel in defined quantities. The dyestuff is filled into an additional small autoclave in the desired (surplus) quantity regulating the carbon dioxide content via, pressure, temperature and/or flow control instruments. The absorption of the dyestuff by the fibre, ie, the diffusion into the inner parts of the fibre, has to meet high levelness standards. The necessary convection of the liquor can be achieved by an agitator within the dyeing autoclave or by moving the substrate.
2. Another option is to penetrate the goods, either by the circulation of the liquor or by utilising the current produced by continuous replenishment of carbon dioxide.
In the latter case, the flow of replenished carbon dioxide will have to be continuously loaded with dyestuff. Residues of dyestuff or fibre admixtures to be extracted prior to dyeing will be collected in a conventional separator. The separation of phase will in this case be initiated by expansion or by raising the temperature.

Dyeing apparatus
An apparatus for dyeing in supercritical carbon dioxide consists of a temperature controller, a vessel heater which surrounds the vessel, a stainless steel dyeing vessel of 50 ml capacity (with a quick release cap), a manometer, a Varex HPLC carbon dioxide pump and a cooler for cooling the head of the carbon dioxide pump. The apparatus was pressure-tested for use up to 350 bars and 100°C. A side arm connects the top and the bottom of the cell outside the heater to allow the supercritical carbon dioxide to circulate by thermal convection.

Procedure for fabric dyeing with SC-CO2 method
The fabric sample to be dyed (size = 10 to 25 cm) is wrapped around a perforated stainless steel tube and mounted inside the auto clave around the stirrer. Dyestuff without auxiliary chemicals was placed on the bottom of the vessel and closed & purged with gaseous CO2 and preheated. On reaching working temperature CO2 was compressed to the working pressure under constant stirring. Pressure maintained during the dyeing period of 0 to 60 min and afterwards the fabric is rinsed with acetone to remove residual dyestuff. The technical parameters of the dyeing procedure is given below:
Table 1
DescriptionActual used CapacityMaximum Capacity
Pressure250 bar500 bar
Temperature103" C350" C
Procedure for yarn packages with SC-CO2 method
Dyeing temperatures and volume flow rates are similar to the conventional dyeing methods, but the advantage here is that the actual dyeing time requires is less. The procedure of the yarn package dyeing is given below.

Table gives an actual comparison between the conventional dyeing procedure and the supercritical CO2 procedure.
Table 2
Super Critical CO2 DyeingConventional Dyeing Procedure
No waste water. Dye remains as powder. No need for dispersing, levelling agentsHigh volumes of waste water with residual dye and other process chemicals
Only 20% of the energy requirementHigh energy requirement
Only 2 hours’ time is required for dyeingDyeing, washing, and drying time is around 3-4 hours/batch
Advantages of supercritical CO2 dyeing • Contaminated wastewater streams and other effluents are not produced.
• Dispersants are not required to solubilise a disperse dye in water.
• Solubility is controllable by pressure, allowing control of the dyeing intensity and colour.
• Diffusivities in the fluid are higher, making mass transfer in the fluid faster.
• Take up of carbon dioxide by the polymer fibre causes it to swell slightly giving faster diffusion within the polymer.
• Viscosities are lower making the circulation of the dye solutions easier.
• Penetration of voids between fibres is fast because of the absence of the surface tension and the miscibility of air with carbon dioxide under pressure.
• No preparation of processing water (by desalting).
• Low energy consumption for heating up the liquor. Energy preservation because drying processes are no longer required (conventional dyeing processes consume about 3,800 kJ per kg of water evaporated).
• No air pollution due to recycling of the carbon dioxide (the gas is not contaminated by the processes).
• Substantially shorter dyeing times.
• No chemicals such as levelling agents, pH regulations etc, have to be added.
• No need for auxiliary agents, disposing agents, adulterants, etc.
• For polyester, no reduction clearing is needed.
• Higher diffusion coefficients lead to higher extraction or reaction rates.

Though there are some disadvantages in this kind of dyeing method, like high pressure requirement for dye solubility, impact of dyeing machine weight on the circulation etc, research work is going on to make them completely viable in the process industry. The supercritical system is also being tried with ammonia for application in mercerizing process.

The textile industry is developing rapidly and newer and newer technologies are introduced day by day. The only formula for survival is encapsulating those innovations into the manufacturing process and making the best of use it for increasing the productivity, and quality. 

Article presented by
Chitra Siva Sankar

SPINNING CALCULATIONS



SPINNING CALCULATIONS  

Conversion of Weight units
Ø  1kg = 2.2046 lbs
Ø  1kg = 1000 grams
Ø  1gm = 15.432 grains
Ø  1lbs = 453.6 grams
Ø  1lbs = 16 oz
Ø  1lbs = 7000 grains
Ø  1grain = 0.0029 oz
Ø  1oz = 437.50 grains
Ø  1penny = 24 grains
Ø  1ton = 2204.6 lbs
Ø  1bundle = 10 lbs
Ø  1bag = 100 lbs
Ø  1mund = 40 kg
Ø  1mund = 88.18 lbs
Conversion of length units
Ø  1m = 1.0936 yards
Ø  1m = 39.37 inches
Ø  1m = 100 cm
Ø  1m = 1000 mm
Ø  1cm = 10 mm
Ø  1yard = 36 inches
Ø  1yard = 0.9144 meter
Ø  1yard = 91.44 cm
Ø  1ft = 12 cm
Ø  1ft = 30.48 mm
Ø  1hank = 840 yards
Moisture Relation for Textile Materials
Ø  M.R =  w/D*100
Ø  M.C = w/w+D*100        =      w/W*100
Ø  M = R/(1+R/100)
Ø  C.C.W  = D * (100+R/100)
Ø  D = C.C.W *(100/100+R%)
Ø  C.C.W = D+R%
Ø  C.C.W = D+(D*R/100)
Ø  Dm) ²
Ø  Volume of air = area (feet sq) * liner speed (ft/min)
Ø  Pm = CA + CB/WA + WB  =  PAWA + PAWB/WA + WB
Blow Room & Carding Section
Ø  Cleaning Efficiency = trash removed/total trash fed *100
Ø  Efficiency = tr/tf * 100        =           tf-tr/tf * 100
Ø  Waste = trash + lint
Ø  Waste Extracted = weight fed * waste%
Ø  Waste Extracted = weight fed weight delivered
Ø  Weight Delivered = weight fed - waste extracted
Ø  Weight Delivered = weight fed * (100 w/100)
Ø  Weight Fed = weight delivered * (100/100 w)
Ø  Lap length (directly proportional) lap change wheel
Ø  Lap length = lap length constant * lap length constant wheel
Ø  Beats/min = rpm of beater * number of strikers
Ø  Beats/inch = beats per minute/feeding rate (inches/min)
Ø  Beats Constant = beats/inch * rpm of paddle roller
Ø  Beats Constant = beat per minute/feeding rate
Ø  Efficiency = actual production/calculated production * 100
Ø  Actual production = calculated production * efficiency
Ø  Actual production = weight of lap(lbs) * number of lap/hr
Ø  M.D = s.s of shell roller/s.s of paddle roller
Ø  Production of B/R (lbs/hr) = production constant * N(shell roller rpm) * W(oz/yd)
ؠ Production of card (lbs/hr) = πDN * 36 * 60 * 1 *ŋ
Ø                                                 36      *    840 * count
Ø  Production of card (lbs/hr) = Ï€DN * 36 * 60 * (weight in ozs) * Å‹/36 * 16                                                                      
Ø  No of scutchers required = feeding rate of cards/production of one scutchers
Ø  No of card required = production of blow room/feeding rate of card deptt
Ø  Production of card (lbs/hr) = delivery rate(m/min) * grain/yds * 1.0936 * 60 * Å‹
Ø                                                                                    7000
Ø  Time to complete full card can = sliver length(yds)/delivery rate(yds/min)
Ø  No. of scutchers required = production of blow room/production of one scutchers
Ø  No. of card required = production of card section/production of one card
Ø  Tension Draft = s.speed of C.C.R/s.speed of Doffer
Ø  Total Lap weight = lap length * weight/yd
Ø  D(Trumpet guide) = 0.015625 * count *
Ø  Waste% age = input output  *  100
Ø                                       Input
Draw frame Section
Ø  Actual Draft  =       weight/yd fed        * No. of doublings
Ø                            weight/yd delivered
Ø  Production(lbs/hr) = delivery rate(m/min) * 1.0936 * 60 * No. of deliveries/7000
Ø  Production(lbs/hr)(only for two deliveries)= delivery rate(m/min) * 0.45 *grains/yd * Å‹
Ø  Production(lbs/hr)  =                       Ï€DN                         * 60 * tension draft * Å‹
Ø                                     36 * 840 * hank sliver
Ø  No. of Deliveries Required= feeding rate of simplex/production of finisher draw frame
Unilap Section
Ø  Production(lbs/hr)  = delivery rate(yd/min) * lap weight(grains/yd) *60 *1.0936 * Å‹
Ø                                                                                    7000
Ø  Note = 1 penny = 24 grains/yd
Comber Section
Ø  Production(lbs/hr)  =      L      *       F * N * H * (100 W) * 60 * Å‹
Ø                                    7000 *      36          *          100
Ø  Note
Ø  L = lap weight in grain/yd
Ø  F = feed rate in inches/min
Ø  N = nips/min
Ø  W = noil %age extracted
Ø  H = no of comber heads
Simplex Section
ؠ Feeding Rate = π * D(dia of back roller) * Rpm(back roller)
ؠ Delivery Rate = π * D(dia of front roller) * Rpm(front roller)
Ø  TPI = TM
Ø  TPI =                 spindle speed________________                                    
Ø            Delivery rate or F.R delivery in inches/min
Ø  Production(lbs/hr) = front roll delivery * 60    *     1     *       Å‹
Ø                                            36                *                 840 * count
Ø  Production(lbs/hr) = flyer rpm     *     60    *    No. of spindles * Å‹
Ø                                           TPI * Hank roving * 36 * 840

Ø  Production(lbs/hr) = 5.7  *  flyer rpm     *   Å‹                                  (for 120 spindles m/c) 
Ø                                                TPI * Hank roving
Ø  TPI =                           flyer speed______________                                    
Ø            Delivery rate or F.R delivery in inches/min
Ø  CPM = front roll delivery(inches/min)
Ø                   Bobbin circumference
Ø  CPI                      CPM_______________                               
Ø             Liner speed of bobbin rail(m/min)   
Ø  CPI CPM
Ø  TCP(NEW) = TCP(old)  *   /
Ø  L.W = L.W(old)  *   / 
Ø  B.W = B.W(old)  *  / 
Ø  Roving Tension winding rate/delivery rate     =         (b f)Ï€D/l
Ø  Roving Tension = (b f)Ï€D/front roll delivery(inches per min)
Ø  Lifter Constant = CPI * lifter wheel
Ø  Turns per meter(TPM) = flyer rpm/delivery speed( meter per min)
Ø   Draft = count deliver/count fed
Ø  New DCP = old DCP  *  old draft/new draft              
Ø  New DCP = old DCP  *  old count/new count 
Ø  No. of Simplex required = production of finisher draw frame/feeding rate of one simplex
Ø  No. of Simplex required = total feeding rate of ring section/production of one simplex m/c
Ring Frame Sestion
Ø  Production(OPS) = spindle speed     *    1    *        1      * 60 * 8 * 16 * Å‹
Ø                                             TPI                36 * 840 * count
Ø  Production(OPS) =               Ï€DN     *      60 *8 *16 * Å‹
Ø                                       36 * 840 * count
Ø  OPS from bags/day = total bags/total frame * No. of spindle per frame
Ø  No. of ring frame required = total production of simplex section/feeding rate of one ring frame
Ø  Traveler speed = spindle speed winding speed
Ø  Winding speed = front roll delivery(inches per min)/bobbin circumference
Ø  Traveler angle = bare bobbin dia/full bobbin dia
Ø  Linear speed of traveler(m/sec) =  Ï€DN/1000 * 60    (where D is ring dia & N is spindle speed)
Auto Cone Section
Ø  Cone Length(meters) = count * cone weight(lbs) * 840/1.0936
Ø  Production(lbs/hr) = delivery rate(m per min) * No. of spindles * 60 * 1.0936 * Å‹ /840
ؠ Production per spindle(lbs/hr) = π * Dia of Drum * Drum RPM * 60 * ŋ
Ø                                                                         36 * 840 * count

Open End
Ø  Production/Rotor(gm/hr) = 0.0006 * N * tex½  * Å‹/T.F              (where N is Rotor Speed)
Ø  Production/Rotor(lbs/hr) = 0.0019 * N * Å‹/T.M * (count)½
Ø  T.F = T.M * 9.61
Some Other Relations
Ø  A.D = M.D * 100/(100 W%)
Ø  A.D = count delivered/ count fed
Ø  A.D = weight fed/weight delivered
Ø  Waste% = (A.D M.D) * 100/A.D
Ø  M.D = A.D  *  (100 W%)/100
Ø  M.D = s.s of delivery roll   *   Driver gear
Ø                 s.s of feed roll      *   Driven gear
Ø  M.D = s.s of delivery roll
Ø                 s.s of feed roll  
Ø  Condensation Factor = s.s of cylinder
Ø                                              s.s of doffer
Ø  Density = mass/volume
Ø  590.5 = tex * count
Ø  Yarn Diameter = k/                                                                                (Where k is Constant)