Quality problems

Following certain refining processes like catalytic cracking, sizeable amounts of nitrogen can appear in light cuts and cause quality problems such as instability in storage, brown color, and gums. 

When ethanoi is present, the risk of separation is much less than with methanol. Nevertheless, the ethanol should be relatively anhydrous (less than 3000 ppm water) moreover, if a fuel containing ethanol comes in contact with a water layer, a migration of ethanol toward the water is observed creating a fuel quality problem manifested by lower octane number and an environmental quality problem in that the water will need to be treated. Distribution of ethanol-based fuels requires extra precaution to ensure dryness in distribution systems. 

The lead time for making a image by film X-Ray is 10 to 15 minutes. Where about 2 minute are needed in inspection by Real-Time X-Ray. Another advantage of Real-Time X-Ray is the feature that the effect of manipulating the part or changing the setting of the X-Ray tube can be observed directly. This is often used in investigating quality problems. 

The combined result of two such determinations yielded a leak size figure of 8.8% of the feed flow (with a relative standard deviation of less than 5%). This figure could sufficiently explain the product quality problems experienced, whose alternative explanation in turn was catalyst poisoning. 

Improperly set tolerances and uncontrolled variation are one of the greatest causes of defects, scrap, rework, warranty returns, increased product development cycle time, work flow disruption and the need for inspection (Gerth and Hancock, 1995). If manufacturing processes did not exhibit variation, quality problems would not arise, therefore reducing the effects of variability at the design stage, in a cost-effective way, improves product quality (Bergman, 1992 Kehoe, 1996). 

Fewer parts means improved reliability, fewer stoek eosts, fewer invoiees from fewer suppliers and possibly fewer quality problems. 

There is a strong eorrelation between assembly effieieney and reported defeet levels for a number of Motorola produets evaluated using the Boothroyd-Dewhurst DFMA teehnique (Branan, 1991). From the results of the study, it is elaimed that DFA euts assembly defeets by 80% and, therefore, has a direet influenee on manufae-turing quality. This may be due to the faet that more effieient design solutions have relatively fewer eomponent parts whieh naturally infers fewer quality problems. However, early life failures, whieh are eaused by latent defeets, are not neeessarily highlighted by DFA teehniques. 

The time required for atmospheric chemical processes to occur is dependent on chemical kinetics. Many of the air quality problems of major metropolitan areas can develop in just a few days. Most gas-phase chemical reactions in the atmosphere involve the collision of two or three molecules, with subsequent rearrangement of their chemical bonds to form molecules by combination of their atoms. Consider the simple case of a bimolecular reaction of the following type-. 

Effort to increase knowledge of indoor air quality problems and controls... 

As mentioned, nonattainment areas will have to implement different control measures, depending on their classification. Marginal areas, for example, are the closest to meeting the standard. They will be required to conduct an inventory of their ozone-causing emissions and institute a permit program. Nonattainment areas with more serious air quality problems must implement various control measures. The worse the air quality, the more controls areas will have to implement. 

It is important to understand the role that each of these factors may play in order to prevent, investigate, and resolve and manage indoor air quality problems. 

As new practices are introduced to prevent indoor air quality problems, an organized system of recordkeeping will help those practices to become part of routine operations and to "flag" decisions that could affect lAQ. The best results can be achieved by taking time to think about the established channels of communication within your organization, so that new forms can be integrated into decision making with minimum disruption of normal procedures. 

Ventilation modification is often used to correct or prevent indoor air quality problems. This approach can be effective either where buildings are underventilated or where a specific contaminant source cannot be identified. Ventilation can be used to control indoor air contaminants by ... 

Solving an indoor air quality problem is a cyclical process of data collection and hypothesis testing. Deeper and more detailed investigation is needed to suggest new hypotheses after any unsuccessful or partially-successful control attempt. Even the best planned investigations and mitigation actions may not produce a resolution to the problem. You may have made a careful investigation, found one or more apparent causes for the problem, and implemented a control system. Nonetheless,... 

Several major studies of indoor-air quality problems have shown that filters would have been able to prevent blocked ducts, fans, and heat exchangers. Other major lAQ problems such as impurities from outside and microorganisms in the system need not arise given the correct choice of filter. 

To involve the staff in a change process, of which the installation or improvement of a ventilation system is one example, is also of vital importance for a successful result. Their knowledge of how the work is or may be done in an effective way, combined with the knowledge of the ventilation expert, increases the chance for an effective and durable solution of an air quality problem. Visualization methods have thereby proved to be effective both to communicate important knowledge and to motivate the staff to take part in the process. ... 

Stopping production to correct quality problems (clause 4.1.2.1.3)... 

A problem is the difference between the way things are and the way things ought to be, as perceived by the one identifying it. A problem relating to the product, process, or quality system (or quality problem) is therefore a difference between what has been achieved and what is required. There is no requirement in this clause for you to actually identify and record such problems (see below). You are only required to define the... 

Ensure responsibilities are clearly understood and documented and clarify who is accountable for the resolution of quality problems. 

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