Summary on Process Quality

The best industry practice from a statistical point of view is to keep careful track of both the processmean and the processvariance.

The process variance can be improved by (a) creatingquality circles (groups of engineers who work diligently on a machine performance to improve process physics) and (b) investing in new capital equipment that is more precisely controlled.

Both these solutions are quite expensive and time-consuming. Again it relates to the dart players: Player Two has to gain more experience, put in more training time, and

I part 3.4 parts per~illionpe[/million_

Process on target

3.4 pa~ts 1 part -'per milli.onper billion

1,350parts:

.oer mtntonI

3.4 parts per million 1.5" Offset

2.4 Question 3: How Much Quality(Q)1 53

try to be as good as Player One. Machine Two has to be studied and modified in cer-tain aspects. Or it has to be sold and replaced with a better one that can deliver the desired accuracy.

The process mean, however, can often be addressed more cheaply by moni-toring the output continuously and using the statistics to keep the mean of each batch centered on the target value. Measured errors in the process mean or target value can often be traced to a fixed offset. This might be related to a misoriented fixture or lithography mask in semiconductor manufacturing, or to a worn cutting tool that has not been adjusted from one batch run to the next.

As one might expect,boththe mean and the variance can be thrown off in some cases. Perhaps a wide variance in the hardness of an incoming work material from an unreliable subvendor will cause scattered results plus tool wear, which will quickly move the mean value as well. Thus in conclusion there is no quick fix to obtaining 3.4 defects per million parts. But companies that want to stay in front obviously have to be part of this goal, refining their techniques in a way that really improves their prod-ucts at an appropriate level of cost.

2.4.6 The "Bigger Picture"-organizational Quality

The Motorola view is that quality assurance touches all aspects of product realiza-tion, not just the factory floor itself. When analyzed "in the large" manufacturing becomes a complex art form. Full-scale industrial design of both the product itself and the production processes that will fabricate the product relies on a huge team of people ranging from classical mechanical and electrical engineers, to marketing experts, to venture capitalists, to industrial psychologists, to advertising executives.

Not only does manufacturing in the large encompass the complete assembly line for a Sony Walkman, or the much larger assembly line for a Ford Mustang, or the gigantic assembly hangers for a Boeing 777, but it also encompasses market analysis and consumers' reaction.

Manufacturing in the large can be effective only in the context of rigorous quality assurance within a "learning organization." Cole (1999) distinguishes orga-nizational/earning from individual/earning by contrasting two social styles. Indi-vidual learning can be applied to one person or to one factory unit, but the key thing is that there are walls around the unit, almost related to a kind of protectionism tinged with paranoia. The old-style British Trade Union attitude seems to capture this the most: craftspeople jealously guarding their secret techniques, and factory units operating for their own bottom line and not worrying about what comes next.

One industrial case study included a metal-extrusion unit that manufactured bar stock that was geometrically correct but so nonuniformly tempered that the down-stream machine shop could not meet production schedules. In the old days the har-ried machine shop had to take care of this problem alone, while the extrusion unit celebrated record production.

With organizational learning, a problem such as the one above becomes everyone's problem, including the sales force. This cooperative attitude toward quality was a very important change in the way U.S. companies began to operate during the period after 1980. It became known as total quality management (TOM).

54 ManufacturingAnalysis: Some Basic Questions for a Start-Up Company Chap. 2

Today, quality assurance is the favored phrase, as discussed in Chapter 10. Many group seminars and books have become available to teach the social styles for these new ways of doing business in which everyone is a learner and people are encour-aged to reveal rather than hide the problems that are occurring in the organization (Senge et al., 1994).

Today, the phrase TQM, in and of itself, is viewed with a small amount of sus-picion (Cole, 1999). For too long it was used as lip service, ignoring the real need for improved and/or controlled quality using more formal statistical methods. In the worst situations, TQM was the "warm and fuzzy"qualitative approach to quality that logic-oriented engineers and MBAs can get grumpy and restless about, since it seems to be common sense. Nevertheless, quality assurance-meaning the careful analysis of process quality and cross-division quality in an organization-is now mandatory for success in modern manufacturing.

2.4.7 Definition of Quality at the TQM Level

At the TQM level, the general term quality can be measured in many different ways (see Cole, 1999; Garvin, 1987). The eight below are from Garvin's work. Rather than summarize a dry list of characteristics, imagine going shopping this weekend for a car or computer. The bullets below the generic category show the kinds of topics that fall into that subcategory:

1. Performance is a measure of basic issues that can be quantified and ranked:

• Car: horsepower, top speed, acceleration, weight, miles per gallon

• Computer: processor speed, amount of RAM, amount of hard disk space, screen size

2. Features are secondary aspects of performance":

• Car: moon-roof, leather seats, designer wheel rims, cup holders

• Computer: CD player, graphics chip, high-speed modem

3. Confonnance is a measure of how well the product fits operational and safety standards:

• Car: emission standards, air-bag requirements, miles per gallon

• Computer: operating system standards, 110 port standards, shielding standards 4. Reliability is concerned with the frequency of breakdowns or failures:

• Car: consumer reports, the 1. D. Powers quality survey on faults and break-downs

• Computer: mean time between failures, system crash frequency, disk drive reli-ability

"Note the "gray line" between performance and features.Twenty-yearsago cup holders were cer-tainly "features."Today, advertisers on television seem to regard the number of cup holders in a minivan as a performance measure.

2.4 Question 3: How Much Quality(QJ? 55

5. Durability is linked to reliability but more concerned with long-term life:

• Car: life of tires, miles before a recommended major part change (e.g., timing belts)

• Computer: long-term life expectancy

6. Serviceability relates to frequency and ease of repair:

• Car: frequency of oil changes. other servicing schedules, ease and cost of service work

• Computer: ease and cost of upgrades, accessibility of major parts 7. Aesthetics relates to how a product looks, feels, sounds, tastes, and smells:

• Car: Porsche versus minivan--enough said!

• Computer: cream-colored cubes versus the iMacs

8. Perceived quality is concerned with the built-over-time reputation:

• Car: despite the dramatic improvements in the

u.s.

• Computer: while consumers might be swayed by price point, larger companies will prefer to buy name-brand products from Sun, IBM, HP. "Intel inside" is important.

2.4.8 The Malcolm Baldrige Award and the ISO 9000 Scheme

1\\'0 well-known schemes have now emerged for evaluating the TQM ability of a par-ticular company. Both awards bring enhanced marketability and recognition.

• The Malcolm Baldrige National Quality Award presented by the U.S. Com-merce Depa:rtment to recognize U.S. companies that excel in quality manage-ment and quality achievemanage-ment

• The ISO 9000 certification of the International Organization for Standardiza-tion, whose objective it is to promote the development of quality standards, testing, and certification

The criteria for the awards are somewhat different (Table 2.5), but they both emphasize the creation of a "learning organization" (Cole, 1999).

2.4.9 A Case Study on Organizational Quality

Some notes on a visit to the Daihatsu Motor Corporation in Osaka, Japan, are now introduced, not to promote Daihatsu in any particular way but to illustrate how a focus on quality assurance has helped the company "swim with much bigger fish" and establish a market niche in the extraordinarily competitive, global automobile market. Daihatsu has extensively relied on the analysis of "What is quality?" and has now established a very clear view of who its customer is. It is especially conscious of establishing its place in the minicar and minitruck market. To do this, it matches its sought-after customer needs to the size, comfort, and fuel efficiency of the vehicle.

Thus its objective function is optimizing cost, safety, and fuel efficiency for this

56 Manufacturing Analysis: Some Basic Questions for a Start-Up Company Chap. 2

TABLE 2.5 Similarities and Differences between the Malcolm Baldrige National Quality Awardand ISO 9000. (FromG. Hutchins. ISO 900D: A Comprahensive Guide to RBgistration, Audit GuidB/ine, andSuccessful Certification, Oliver Wight Publications, Inc" Essex Junction, VT. Copyright(c)1993 by Oliver Wight Publications, Inc. reprinted with permission of John Wiley & Sons, lnc.!

Baldrige ISO 9000

Exclusive, only two winners per category Quality criteria higher and more demanding, stressing customer FIrst step in the TQM journey Systems-oriented

Version ISO 9001 generically covers Baldrige criteria Focus on control

Inclusive, all can become registered Quality criteria generic; customer satisfaction and continuous improvement not emphasized

limited market sector. Daihatsu minitrucks are ubiquitous in the small commercial alleyways of Tokyo, making small volume deliveries to shops and the like. On the congested commuter roads of Osaka, Kyoto, and Tokyo, its minicars are also very evi-dent. Younger first-time buyers also seem to represent a fair share of Daihatsu's cus-tomers.

During the visit, Daihatsu crash tested a car and emphasized that it is possible to make a high-quality yet inexpensive product. Its quality movement begins with the study of the intended market. It then leads into integrated design and manufacturing for the establishment of a low cost product with higb quality. For example, its quality assurance studies showed that customers still valued safety above all else, despite the need for a relatively low cost vehicle. Thus Daihatasu continued to emphasize safety issues in its design, and later safety was particularly emphasized in its marketing. As a specific example, while good design practices were used to minimize the number of weld points in the body (thus reducing cost), no compromise was made to structural safety of the chassis's crumple zone.

Another observation from all such studies of the automobile industry (whether in Osaka, Detroit, or Coventry) is that the right type of automation increases overall quality. This is especially true in the welding and bulk vehicle assembly lines where the work is heavy and requires good alignment. In the future, engineers will still be striving to automate as many operations as possible and move into other more exacting areas of vehicle assembly. An interesting finding from studies by Xerox and by Boothroyd and Dewhurst (see Chapter 8) is that to push automation to the limit and create the best quality, any peg-in-hole-like assembly insertions and so forth should be vertical. From an "integrated manufacturing," orTQM, viewpoint it is thus

2.5 Question 4: How Fast Can the Product Be Delivered (0)7 51

useful to take a very broad view and even consider the redesign of key elements of the engine, transmission, or body just to promote vertical assembly.