1. Quality concept

1.1. Introduction
What does quality mean?
What has quality got to do with commercial success?
There are many definitions of quality and also many opinions. No definition will therefore be given at this point. It is simpler to say what 50% or 80% or 98% quality means. For example, 98% quality is equivalent to1:
· no running water for 7 days a year
· 30 mins. without power per day
· or monthly wages are not paid to 1.2 million German employees because it was forgotten to transfer the money.

The PMIS1 studies state that quality, market shares and the ROI (Return on Investment) have a strong positive correlation2 .

· Quality results in increase of market share
· Quality produces better prices in the market
· Quality can compensate for a lower market share
· Quality and high market share have an above-average influence on profits3

It is well known that process reliability and reproducibility promote product quality. But quality is also a product feature, which our customers demand and cannot be copied by our competitors.
Lack of quality causes quality costs:

We alone are responsible for quality costs. No competitor, no customer and no high personnel costs can be blamed for them. If we reduce these quality costs, we can practically credit this to our earnings side as profit. Quality is the guarantee of commercial success. The following statement thereby gains validity:

"The machine constructor can make a contribution to the commercial success of the textile finisher by increasing quality, reproducibility and process reliability."

1.2. Quality concept over the course of time

The concept of quality has changed considerably during the past 50 years. In the 50s and 60s quality was equated with technical perfection. "Made in Germany" was synonymous throughout the world for a high quality standard. Products were faultless and distinguished by their high technical standard. Quality was exclusively a technical parameter. Those who have jumped the bar at the highest level are the winners.

In the 1970s "Made in Japan" initiated a new wave of quality consciousness. It started with the Japanese photographic industry, followed by hi-fi and the motor trade. Cheaper mass-produced articles, which can often be replaced, corresponded to a higher living standard. Long life was no longer in demand. Quality was also no longer measurable, since customers had their own interpretation.

Quality is in the eye of the beholder.

Then in the 1980s came the euphoria for mass produced articles and the bar height for quality was clearly defined. This produced products of relatively high quality at an acceptable price. Quality was exactly defined. The bar for the high jumper is exactly defined. The aim is to jump over the bar - no more and no less. Quality was therefore no longer something absolute, but something exactly defined.

A brake was put on the hunt for length and height.

During the 1990s technology matured to such perfectionism that no further limits were set to technical quality. The quality technically possible lies above the quality required. People suddenly turned out to be one of the weak links in the value added chain. They were no longer able to follow the technology.
From the last 50 years quality policy therefore emerged the 2000+ quality concept, which is defined as follows: Quality is achieved when the provision of performance is economical, ecological, socially balanced and lasting.

2. Points of reference for optimizing quality in textile finishing processes

2.1 Causes of quality deficiencies

From the cause-effect diagram according to K. Ishikawa4 (best known Japanese quality expert) the 4 causes machines/fixtures, people, methods and material are decisive.

Machine/fixture: Deviations in quality can be of a mechanical nature, but can also occur owing to insufficient maintenance, since the machine has a high proportion of wearing components (the essence of wearing parts is considered again separately later). A significant loss of quality, however, is also too low productivity or inadequate washing result. Both are faults in the specification of the system, since the expectations of the textile finisher are not satisfied.

Method: The production sequences selected, composition formulae, etc. do not comply with the anticipated quality. With desizing for example, this can be caused by the selected method not being suitable for all size types. Since, however, the size also changes with changing raw material and the desizing bath is not normally changed continually, a multi-functional desizing bath is required for as many size mixtures as possible.

People: While formerly all textile finishing processes could be influenced by manipulations of the operator and these manipulations were also necessary, the result was largely in the hands of the operator. While formerly the quality of the machine construction held pride of place, today the control of the process and assurance of the result assume most importance, regardless of personnel and geographic influencing parameters.

Material: A comprehensive quality policy also calls for inclusion of the supplier in the added value chain. Unfortunately it is not possible for the textile industry in central Europe for geographical reasons to bind the cotton manufacturers closer. It is well known that the imported raw materials are subject to wide fluctuations. This situation is further deteriorating for commission finishers, since the origin of the cotton is entirely unknown. For manmade fibre materials it has already been possible to involve the suppliers. These are in particular technical fibres such as PA 6.6 for airbags as well as Lyocell and Tencel for the fashion clothing trade. The fibre manufacturers are available to offer advice here to the finisher.

2.2 Contribution to improving the quality within an investment cycle

Based on the cause/effect diagram the machine constructor can make a contribution at various times to quality and process reliability within the life cycle of a textile finishing machine (figure 2).

Phase 1: Investment requirement/new procurement (textile finisher) - sales process (machine constructor)

Normally the opinion of the marketing or distribution employee is that they have scarcely anything to do with quality, since this subject belongs rather to manufacturing or quality assurance5 . This has for a long time been a mistake of the machine manufacturer. The satisfaction of consumer and customer wishes is required in order to meet the expectations of the textile finisher. In practice this corresponds to the preparation of a specification. In these phases the relevant dimensions and guidelines are also prepared, which are later consulted for evaluation of the result.

Phase 2: Determination of preparation/ methods (textile finisher) - production, installation, commissioning (machine constructor)

Phase 2 serves more or less as a transition for the textile finisher. For the machine constructor this is the most important phase. He has to implement the criteria determined in phase 1 in the machine construction.

The new textile finishing machine is produced, installed and put into service. The textile finisher can make suitable preparations in this phase. He can prepare methods and compositions, as well as train the future operating personnel.

Phase 3: Use (textile finisher) - customer service, spare-parts service (machine constructor)
For the textile finisher the phase then begins for redemption of the investment made. High quality leads to greater commercial success, e.g. the PIMS studies show that high quality leads to increase of market share and also to the prices set in the market. In other words, there is a positive correlation between quality and market share.

The textile finisher must ensure that a uniform and constant product quality is achieved. The foundation stone for this was laid in phase 1. The product concept of the machine constructor must be matched to the demand. If deviations nevertheless occur, these must be resolved within the scope of the so-called exceptional case. The customer service can make a contribution here either by direct telephone line or by a telephone-modem connection to control the system for elimination of the fault as quickly as possible. The utilization phase of a textile finishing system still usually lasts over 10 years in Europe. Preventive maintenance avoids the occurrence of undesirable faults and deviations. The spareparts service of the machine constructor helps to keep the machine in the original condition all the time.
Phase 4: Investment requirement, new procurement

The best product concept and the best maintenance do not help and innovation in machine construction and process development result in the quality of the existing (old) machine one day no longer being state-of-the-art. This can either be the technical quality or also lower production costs in a modern system. The modern concept of quality always places quality in conjunction with the price. (Juran 6:What brings me quality? What costs me quality?7). A substitute investment must therefore improve both the actual product quality as well as the production costs.

2.3 Extract from possible quality programs
Examples will now be given below of quality-promoting measures in textile machine construction. The following quality programs are presented in detail:

· Quality management in marketing
· Quality management in development and design with examples
· Avoidance of potential sources of danger
· Incorporation of freedom from maintenance
· Quality management in production based on the following examples
· Continuous monitoring of reference and actual values and continuous correction
· Automation of sequences possible to influence
· "Speak with data"8
· Regulation of exceptional status based on example

3. Examples
3.1 Quality management in marketing:
Marketing is the primary interface between the company and the market, while at the same time also being the start to a possible commercial success. The machine constructor is confronted with the daily questions:

What does the market demand?
What does the textile finisher demand for his own best solution?
The marketing department is answerable for the first question. Continuous market analysis and market research are indispensable for revealing trends. This article does not consider the various market research tools in detail and looks only at the 2nd question.

The textile machine constructor must successfully produce the best combination of modules from his production program in order to offer an individual solution for the textile finisher. The objective must be to find the optimum solution to satisfy the individual requirements of the textile finisher from familiar and proven elements. Only proven elements can eliminate weak points, which otherwise cause quality breakdowns. This does not mean that new developments are of poor quality, but rather that new developments must be composed of familiar elements. In the formulation of the quality concept 2000+ It was stated that quality is also something durable and continuity is called for.

Following takeover of the wet finishing division of the company KTM/Krefeld, Benninger today has a full range of wet finishing plants for open width treatment of woven and knitted fabrics.The product range of Benninger has therefore been supplemented in washing and bleaching with the machine program for knitted goods. In the dyeing sector (BEN-COLOUR) with the BICOFLEX padding machine the last product gap has now also been closed in continuous and semi-continuous dyeing. In order to provide the customer with the complete infrastructure, Benninger now has a powder dissolving station developed by itself and fluid chemicals station in the production program. All machine modules can be combined without interfaces. In addition to the machine elements Benninger also supplies the process and drive control units.

3.2 Quality management in K&E:

"Avoidance of potential sources of danger" - wear of roller rubber when washing off textiles with high chemical loading. Two questions must be answered for potential sources of danger:
1st question: Do I really need this part?
2nd question: Must I adapt this part to the operating conditions or can the conditions be improved for the critical part?
Rubberized rollers are critical components in the textile finishing industry and also represent a potential source of danger. Large amounts of chemicals and high temperature lead to rapid and uncontrollable wear.

Following an impregnation and reaction process, residual chemicals, fibre- accompanying materials and converted reaction products must be washed out. Many reaction processes run in a steam atmosphere. In addition to rapid reaction kinetics, the accompanying materials such as oil and grease are also converted to a low viscosity form. A cooling of the cloth at this point during washing would return grease and oils to the original high viscosity form. It is known that the washing efficiency in hot water is likewise substantially higher than in cold water. Washing processes immediately following steaming processes therefore represent unfavourable conditions for rubber rollers. Cold washing would improve the operating conditions, but worsen the textile result. In other words, the critical part (here the first washing section following a reaction process) must be adapted to the environmental conditions. This is most simply achieved by avoiding rubber rollers at such places.

The FORTRACTA washing compartment from Benninger Uzwil AG has been specially developed for removing surface soiling and high chemical loads. The textile web is taken upwards in 2 shafts. The washing liquor runs down like a waterfall under gravity. A high washing effect is achieved by means of this counterflow principle in the shaft. The liquor separation is achieved by stripping rollers and flat jet nozzles at the outlet of the compartment.

The FORTRACTA washing compartment consists of a stainless steel design with 2 washing chambers. There are two narrow shafts between the 2 washing chambers. The design is such that the washing compartment is only provided with smooth surfaces and is therefore self-cleaning. There is no need for rubber rollers as drawing or liquor separating elements. Chemical loads are practically halved in a FORTRACTA prewashing assembly. This corresponds to the washing effect of a conventional high capacity washing compartment with 30 m fabric content. This high efficiency can only be used once, however, to remove chemicals and contamination adhering to the surface. The dilution wash can then be continued without problem in conventional roller vats with the prewashed cloth. Since the chemicals and dirt have already been considerably reduced, rubber rollers can be used again. With the FORTRACTA prewashing compartment Benninger has created a unit which complies with the quality objectives "avoidance of danger sources" and "quality at acceptable costs (fitness for use)".
3.3 "Incorporation of freedom from maintenance"- TPM Total Productive Maintenance
The expression "incorporation of freedom from maintenance" originates from TPM (Total Productive Maintenance), which was already introduced in Japan in the mid-70s.9

It is often not the actual maintenance which is the problem, but rather the time for maintenance that is decisive. The characteristic of wearing parts is that they attain their highest quality following a brief introductory phase. They then decline increasingly in performance with increasing wear and the textile result changes slowly until final quality failure.

There is no place for wearing parts in modern textile machines, which have a direct influence on the textile results. It was long customary to use transmission drives in textile finishing plant construction. Chains, belts and mechanical sliding clutches were used. These are all wearing parts, which cannot guarantee reproducibility of textile results with regard to cloth transport, freedom from creasing and fabric extension.

Benninger has replaced all transmission drives by individual roller drives. In the vertical washing vats all top rollers can be fitted with a.c. motors In the pretreatment and dyeing steamers, as well as the hotflue and thermosol drying chambers, the drive components can be selected according to cloth weight and demand. In the TRIKOFLEX drum washing machine the drum drives are likewise fitted with wear-free a.c. drives. A.C. drives are practically wear-free and require very little maintenance. They therefore ensure a reproducible and creaseless cloth transport.

3.4 Automatic metering of chemicals using inductive flowmeters for impregnation processes as exemplified by the IMPACTA high-moisture application assembly:

Hardware and software solutions, which satisfy automatic control and regulation functions, are assigned to the category of quality management in production. With metering of chemicals it is a matter of satisfying the following quality criteria:

· Continuous MONITORING and comparison of reference and actual values in order to obtain reproducibility throughout the period of use.
· Provision of back-up solution for exceptional circumstances.
· Elimination of manipulation possibilities by an expert system

A chemicals station consists for each chemical of a feed pump, an inductive flowmeter and a control valve (figure 4).

The concentrated chemicals are fed into the circulating pipe of the IMPACTA to ensure good mixing. The reference value is calculated according to the recipe entered (ml chemical per kg cloth) depending on the cloth throughput, determined from square metre weight multiplied by the width and the speed.
An exactly defined volume of chemicals is added by metering in ml/kg corresponding to the cloth throughput. Inductive flowmeters measure the ACTUAL flow and compare this with the REFERENCE. If a deviation from the REFERENCE and ACTUAL values occurs, an automatic dynamic correction of the flow volume is made. The impregnating system is self-regulating. Water is added depending on the level. If more water is added with the cloth, the amount of water added dependent on level is reduced automatically.

The metering system operates in the regulating range 1:100. If minimum volumes are required, the metering system changes over automatically to clock cycles.

The IMPACTA is a high moisture application system for wet on wet impregnation and is mainly used for preliminary treatment. A major advantage of this unit is that a liquor exchange takes place in the bath. In other words, the water added is exchanged for chemicals. Not all articles have the same liquor exchange rate and the same liquor uptake. The bath concentration in ml/l, however, is largely influenced by these two parameters. If articles with different characteristic are produced in succession without production stoppage, it is necessary to change the bath concentration in ml/l online. All Benninger systems are fitted with a "programmable logic control" (PLC).

This makes it possible to automate processes of this kind. As can be seen from formula 1 for the calculation of the liquor concentration, the bath concentration is calculated from the feed liquor concentration in ml/kg (the actual recipe) and the liquor pick-up inlet and outlet and the exchange factor. Computation from the liquor pick-up and the exchange factor is called "effective pick-up". It can be seen from formula 2 that the bath concentration changes by variation of the "effective pick-up" with the same feed liquor concentration. If therefore the "effective pick-up" changes, a change of bath concentration is necessary.

Formula 1:
Feed liquor conc. (ml/kg) Liquor pick-up inlet x liquor exchange +
(Liquor pick-up outlet - liquor pick-up inlet)

Formula 2:
Feed liquor conc. (ml/kg)
Effective pick-up
Benninger has created an expert system, in which over 2000 individual tests on a wide variety of articles, speeds, temperatures, etc. play a part. By definition of the article the relevant effective pick-up is automatically assigned to the composition formula via the data archiving program and the initial concentration and the necessary volume of chemicals calculated in litres. In the case of a first filling this is very simple, since the volume of the IMPACTA is known and stored in the PLC. Alteration of the concentration during an article change is also possible without stoppage. By changing the "effective pick-up" or by loading a new composition formula, the control unit recognizes that this results in a change of liquor concentration. The user can maintain a dialogue with the control unit by means of a touch-screen and is asked whether a change of bath concentration is required. The change of concentration is then started by being acknowledged. Even the acknowledgement operation could be automated. For this purpose a max. tolerance limit for e.g. 2% deviation from the original bath concentration must be specified. If the tolerance limit is exceeded when changing the article, the change in concentration takes place automatically.

The change in concentration takes place in such a way that the bath must either be strengthened with chemicals ("effective pick-up new" less than "effective pick-up old") or it must be diluted (effective pick-up new" greater than "effective pick-up old").

In the first case the necessary volume of chemicals is automatically added within seconds to the existing bath. In the second case water is added for dilution.

Metering of feed liquor in ml/kg is not affected in either case and is continued.

The metering system described complies with the requirements of quality management with regard to REFERENCE-ACTUAL comparison and control, as well as regulation of the exception status as exemplified by change of concentration.

3.5 Regulation and control of liquor pick-up in impregnating systems for specific articles
The following quality criteria must be satisfied:
· Reproducible liquor pick-up
· Provision of a monitoring tool (Speak with Data)
· Control of exception status

The contribution by Benninger Uzwil AG to the assurance of an article-specific and controllable liquor pick-up should be mentioned again on the IMPACTA high-moisture impregnating unit. This example can be used in the same way, however, for all impregnating processes and for the BICOFLEX padding machine.

A special 2 roller squeezing unit ensures a controlled and speed-independent liquor pick-up. Previously 2 roller squeezers were unsuitable with regard to controllability in the high moisture range. Benninger has modified the design so that the dead weight of the squeezing roller has no influence on the liquor pick-up, since the centre of gravity of the squeezing roller lies directly above the pivot point of the squeezing mechanism. The pneumatic system has been designed so that the smallest pressures can be set exactly.

Owing to the low pressure there is a danger that the squeezing roller nip would spring open when passing seams or other thick places. This condition is termed an exceptional status in quality management.

Independent closing is not possible owing to the minimum nip pressure. Benninger has positioned a sensor to monitor the nip joint, which continuously measures the distance of the two rollers. If an opening of the squeezer takes place for the reasons mentioned above, this is immediately detected and a special nip closing algorithm is activated. The squeezer is returned to its original position within 2 seconds and the bleaching liquor is supplied in its customary uniform and reproducible volume.
Benninger places emphasis on the application of high moisture on the fabric web suitable for the specific article. A maximum application would often exceed the liquor bearing capacity of the treated fabric.

Liquor losses occur following the addition of steam condensate in the bleaching steamer, which lead to non-reproducible results and loss of chemicals by precipitation.10
Benninger also has a system for measuring the liquor addition and approximate representation of the total liquor pick-up. Edwards Deming, a quality expert from the USA, advocates the idea.

"Speak with data"
Deming states that facts and data play an important role for decisions on the evaluation of quality or lack of quality. He criticizes decisions reached on the basis of intuition and sixth sense. 11
This formulation is particularly useful in the textile finishing industry marked by tradition. The relative figure liquor pick-up is familiar to experts and is a value with which it can be assessed blind whether a parameter corresponds or not.

Modern textile finishing systems have a lot of information thanks to the PLC controller, which are only bits and bytes to software people and have no significance. This is also true of the information obtained from the inductive flowmeters. The software for a metering system calculates the metered volume in ml/min. from the cloth throughput and the composition formula. It was forgotten that all information is present in the PLC controller for the calculation of a resulting liquor pick-up.

The sum of all infeeds to an impregnating system is obtained from the inductive flowmeters. When computed, this gives the total supply per minute to the impregnating system. The quotient of liquid volume supplied and cloth throughput gives the value of liquor addition (the density of the bleach liquor is ignored here). The sum from the addition and the inlet moisture, which is obtained quite reliably from the Benninger experts system, gives the approximate total liquor pick-up.

A proportional figure can be created here by means of a simple mathematical algorithm to serve as an important monitoring aid for every textile specialist. It is not a matter here of attaching an additional sensor system to the machine, but of processing information from existing regulating and control tools required for other purposes, in such a way that it is useful for the user. This is possible by the addition of all inputs to an impregnating compartment and a simple mathematical operation. The machine operator has a control instrument here, which provides him with continuous information about an important proportional figure and can result in early fault detection. The average liquor pick-up can also be recorded on the production report, printed out and used for quality assurance. The positive factor for the machine purchaser is that the investment amount is only insignificantly increased by additional software (the hardware is necessary in any case).

4. Summary
Quality and commercial success are closely related. The machine constructor has various points of reference for a positive influence on the quality of the result by the textile finisher. Quality management begins with marketing, continues with design and development and the quality must then be demonstrated in daily use, i.e. during production by the textile finisher. The essential features of quality policy in the construction of textile finishing systems are avoidance of potential sources of danger, incorporation of freedom from maintenance, monitoring of reference and actual values and handling of the exception status. All these are measures for increasing process safety and reproducibility. Quality leads to confidence of customers and establishment of a close customer bond. Therefore for the textile finisher and machine constructor:
QUALITY is achieved when the customer returns and not the product

5. Literature and source index
Backhaus Klaus: Industriegütermarketing, 5th edition, Munich 1997, Benninger, BEN-BLEACH, brochure, Flawil 1999
Hauser Bondo: Qualitätsmanagement in der Textilindustrie, in Textilveredlung 5/6 1998, Zürich 1998
Hopfenbeck Waldemar: Allgemeine Betriebswirtschafts- und Manage-mentlehre, 4th edition, Landsberg am Lech, 1991
Kotler Philip: Marketing- Management, 9the edition, Bliemel Friedhelm Stuttgart 1999
Oess Attila: Total Quality Management, Die ganzheitliche Qualitätsstrategie, 3rd edition, Wiesbaden 1993.