Continual improvement

The specific character of NDT related to the quality assessment of safety critical products and objects requires constant analysis and continuous improvement of processes and their interconnection. Sometimes interaction of processes is very complicated (Figure 3) therefore the processes have to be systematized and simplified when possible to realize total quality management in NDT. 

With the wealth of infonnation contained in such two-dimensional data sets and with the continued improvements in technology, the Raman echo and quasi-echo techniques will be the basis for much activity and will undoubtedly provide very exciting new insights into condensed phase dynamics in simple molecular materials to systems of biological interest. 

The properties of SAN resins depend on their acrylonittile content. Both melt viscosity and hardness increase with increasing acrylonittile level. Unnotched impact and flexural strengths depict dramatic maxima at ca 87.5 mol % (78 wt %) acrylonitrile (8). With increasing acrylonitrile content, copolymers show continuous improvements in barrier properties and chemical and uv resistance, but thermal stabiUty deteriorates (9). The glass-transition... 

Another significant benefit of a LIMS is the improvement of the overall quaUty of the laboratory. In the case of a laboratory, quaUty is defined as satisfying customer needs in the areas of accuracy, reUabiUty, clarity, and timeliness of analytical information. LIMS can enhance quaUty in a number of ways, eg, in checking conformance to requirements, in organizing and prioritizing work to ensure timeliness, in measuring laboratory performance in areas of technical quaUty and efficiency so as to provide continuous improvement, and in helping the laboratory to communicate clearly, completely, and consistendy (16). 

Polyethylene. Traditional melt spun methods have not utilized polyethylene as the base polymer because the physical properties obtained have been lower compared to those obtained with polypropylene. Advances in polyethylene technology may result in the commercialization of new spunbonded stmctures having characteristics not attainable with polypropylene. Although fiber-grade polyethylene resin was announced in late 1986 (11,12), it has seen limited acceptance because of higher costs and continuing improvements in polypropylene resin technology (see Olefin POLYMERS, POLYETHYLENE). 

Nuclear power has achieved an excellent safety record. Exceptions are the accidents at Three Mile Island in 1979 and at Chernobyl in 1986. In the United States, safety can be attributed in part to the strict regulation provided by the Nuclear Regulatory Commission, which reviews proposed reactor designs, processes appHcations forUcenses to constmct and operate plants, and provides surveillance of all safety-related activities of a utiUty. The utiUties seek continued improvement in capabiUty, use procedures extensively, and analy2e any plant incidents for their root causes. Similar programs intended to ensure reactor safety are in place in other countries. 

Responsible Care is the incentive sponsored by the Chemical Manufacturers Association (CMA). Any CMA company must embrace the philosophy of continuous improvements of health, safety, and environmental efforts accompanied by an open communication to the pubHc about products and their production. Thus the total impact of any product on the environment, from the extraction of raw materials, their beneftciation, transportation, production of final product, and disposal of the product at the end of its useful life, must be taken into consideration. 

Some of the early Thiokol soHd mbbers are stiU made and used in printing roUs, solvent-resistant spray hose, gaskets, and gas-meter diaphragms. Many of the polysulfide products have been in use since the 1940s with an exceUent track record. Continuing improvements in technology keep these products competitive. 

Quality in Japan. Japanese economic prowess has been attributed variously to such quahty improvement activities as quahty circles, statistical process control (SPG), just-in-time dehvery (JIT), and zero defects (ZD). However, the real key to success hes in the apphcation of numerous quahty improvement tools as part of a management philosophy called Kaizen, which means continuous improvement (10). 

This technique, widely used in U.S. plants during World War II, helped to ensure rehabihty and performance of military supphes. Once the war ended, SPG lost favor. However, in the face of rising Japanese product quahty, SPG was reintroduced. In the chemical industry the use of SPG continues to grow in popularity as a key element of an ongoing continuous improvement. 

Total Quality Management. Total quahty management (TQM) is the term which encompasses all of the continuous improvement activities with the goal of world class quahty. This corporate culture sets up the conditions for a climate favorable to companywide improvement. 

Reichsteia and Grbssner s second L-ascorbic acid synthesis became the basis for the iadustrial vitamin C production. Many chemical and technical modifications have improved the efficiency of each step, enabling this multistep synthesis to remain the principal, most economical process up to the present (ca 1997) (46). L-Ascorbic acid is produced ia large, iategrated, automated faciUties, involving both continuous and batch operations. The process steps are outlined ia Figure 7. Procedures require ca 1.7-kg L-sorbose/kg of L-ascorbic acid with ca 66% overall yield ia 1977 (55). Siace 1977, further continuous improvement of each vitamin C production step has taken place. Today s overall ascorbic acid yield from L-sorbose is ca 75%. In the mid-1930s, the overall yield from L-sorbose was ca 30%. 

Statistical quality control is used to first measure and then continuously improve product quality. For example, The Dow Chemical Company s average 1989 performance compared to the typical sales specification were purity, = 99.65 wt % color, APHA = 4 acid (as HCl) = 7.3 ppm and water = 26 ppm. Averages of properties were based on rail car and tank tmck shipment samples during 1989. 

There are several mathematical methods for producing new values of the variables in this iterative optimization process. The relation between a simulation and an optimization is depicted in Eigure 6. Mathematical methods that provide continual improvement of the objective function in the iterative... 

Measurements and Audits. The enabling element of continuous improvement is measurement. An old rule of thumb says that increased accuracy in measuring an energy use ultimately yields a reduction in use equal to 10% of the increased closure of the balance. A basic principle of economics is that any thing that is free is used in excess, ie, an unmetered electrical use is bigger than expected by at least 10%. Metering of the cost elements at each unit in a chemical plant provides effective accountabhity. Measurements should be linked via computer software to production as weh as to weather to result in maximum feedback. 

While most companies within the process industries recognize the importance of information technology in managing their businesses, this technology has been a source of considerable frustration and disappointment. Schedule delays, cost overruns, and failure of the final produc t to perform as expec ted have often eroded the credibility of information technology. However, immense potential remains for the technology, and process companies have no cnoice but to seek continuous improvement. 

Rubber and Elastomers Rubber and elastomers are widely used as lining materials. To meet the demands of the chemical indus-tiy, rubber processors are continually improving their products. A number of synthetic rubbers have been developed, and while none has all the properties of natural rubber, they are superior in one or more ways. The isoprene and polybutadiene synthetic rubbers are duphcates of natural. 

CCPS G-55. Guidelines for Performance Measures for Continuous Improvement of Process Safety Management Systems. American Institute of Chemical Engineers, Center for Chemical Process Safety, New York. 

It is based on a philosophy of continuous improvement and partnership. The intent is to establish dialogue and feedback for a clearer understanding of requirements and capabilities. The system has several basic steps ... 

The company has shown adequate evidence that a well-defined system is in place and documented which addresses the area in question. Ultimate goals may not have necessarily been reached however, the company is well on their way towards continuous improvement for the specific question/area. 

QRA results can guide decision makers in their quest for continuous improvement in risk reduction, but zero risk is an unattainable goal. Any activity involves some risk. Even if it were hypothetically possible to eliminate the risk of every accident scenario in a QRA, some risk would still remain because no QRA examines every possible accident scenario. At best a QRA identifies the dominant contributors to risk from the system as it existed at the time of the analysis. Once those are eliminated, other minor risk contributors (including many that were left out of the original QRA because they were negligible contributors, as well as new risks introduced by changes to eliminate the original risks) remain as the new dominant risk contributors. 

Figure 20.6 shows how this evolutionary process has resulted in a continual improvement of creep properties of nickel alloys over the last 30 years, and shows how... 

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