Production performance

Typical feedstock composition used for tame synthesis. Product performance and properties. 

Other important properties that can be measured in the laboratory include sealabiHty, printabiHty, or coating adhesion. Many of these tests have been developed by the film manufacturer in cooperation with customers and are specifically designed to measure product performance in the end use. Some tests, like sealabiHty, can be standardi2ed to time, pressure, and temperature of sealing with instmment-measured peel values, but other tests are subjective, such as evaluations of printing loss to puUoff by adhesive tape. 

Accuracies of the flow meters discussed herein are specified as either a percentage of the full-scale flow or as a percentage of the actual flow rate. It may be convenient in some appHcations to compare the potential inaccuracies in actual volumetric flow rates. For example, in reading two Hters per minute (LPM) on a flow meter rated for five LPM, the maximum error for a 1% of full-scale accuracy specification would be 0.01 x 5 = 0.05 LPM. If another flow meter of similar range, but having 1% of actual flow rate specification, were used, the maximum error would be 0.01 x 2 = 0.02 LPM. To minimize errors, meters having full-scale accuracy specifications are normally not used at the lower end of their range. Whenever possible, performance parameters should be assessed for the expected installation conditions, not the reference conditions that are the basis of nominal product performance specifications. 

C. J. Benning, T/asticEoams, Vol. 1, The Thjsics and Chemistry of Product Performance andProcess Technology,WUey Sons, Inc., New York, 1969. 

Etom the customer s point of view, there is an optimal level of standardization. Increased standardization lowers costs but restricts choice. Furthermore, if a single minimal performance product standard is rigorously invoked in an industry, competition in a free market ultimately may lead the manufacturer of a superior product to save costs by lowering his product quaHty to the level of the standard, thus denying other values to the customer. Again, excessive standardization, especially as appHed to design or how the product performance is to be achieved, effectively can limit technological innovation. 

Quality in the Chemical Industry. The chemical iadustry uses quahty as a strategic tool for financial success. Oae measure of quahty is the degree of product variatioa from lot to lot. Ia the chemical iadustry, it is oftea difficult to provide product speciftcatioas comprehensive eaough to easure product performance ia all apphcatioas (21). Therefore, the manufacture of product having a minimum of lot-to-lot variabihty allows the customer to use the product without modifying their formulation or process to accommodate such variation. 

Special Tests. Even though the American Society for Testing and Materials offers a wide range of test methods, there are other special tests that are imposed upon the manufacturer by consumers, the military, the U.S. Government, and ia some cases local or municipal governments. These tests are generally very specific and are oriented toward particular service conditions. In many iastances, the producers develop special tests within thek laboratories to solve customer problems or predict product or production performance. Many of these tests subsequentiy are adopted by ASTM. 

Alkali sihcates are used as components, rather than reactants, in many appHcations. In many cases they only contribute partially to overall performance. Utility factors are generally not as easy to identify. Their benefit usually depends on the surface and solution chemical properties of the wide range of highly hydrophilic polymeric siUcate ions deUverable from soluble sihcate products or their proprietary modifications. In most cases, however, one or two of the many possible induences of these complex anions cleady express themselves in final product performance at a level sufficient to justify their use (102). Estimates of the 1995 U.S. consumption of sodium sihcates are shown in Table 6. 

Quahty control testing of siUcones utilizes a combination of physical and chemical measurements to ensure satisfactory product performance and processibihty. Eor example, in addition to the usual physical properties of cured elastomers, the plasticity of heat-cured mbber and the extmsion rate of TVR elastomers under standard conditions are important to the customer. Where the siUcone appHcation involves surface activity, a use test is frequently the only rehable indicator of performance. Eor example, the performance of an antifoaming agent can be tested by measuring the foam reduction when the sihcone emulsion is added to an agitated standard detergent solution. The product data sheets and technical bulletins from commercial siUcone producers can be consulted for more information. 

Soon after the first successful diamond synthesis by the solvent—catalyst process, a pilot plant for producing synthetic diamond was estabUshed, the efficiency of the operation was increased, production costs declined, and product performance was improved while the uses of diamond were extended. Today the price of synthesized diamond is competitive with that of natural diamonds. 

Vehicles are selected by two methods. In one a concentrate is designed directiy for a resin system, the resin itself, or a compatible resin. Thus when the concentrate is made there is a minimal effect on the properties of the final color. In PVC, often a plasticizer such as dioctyl phthalate (DOP) is used. In the other method, concentrates are made with a commercial universal concentrate vehicle. Concentrate manufacturers and some resin manufacturers have developed vehicles that can incorporate many types of colorants and can be used across many classes of polymers without adversely affecting final product performance. 

Designing an experiment is like designing a product. Every product serves a purpose so should every experiment. This purpose must be clearly defined at the outset. It may, for example, be to optimize a process, to estimate the probabiUty that a component operates properly under a given stress for a specified number of years, to evaluate the relative effects on product performance of different sources of manufacturing and end use variabiUty, or to determine whether a new process is superior to an existing one. An understanding of this purpose is important in developing an appropriate experimental plan. 

Special tests are mn for certain customers. Such tests reflect how the product performs in a particular appHcation. 

The predictions checked in the pilot-plant reactor were reasonable. Later, when the production unit was improved and operators learned how to control the large-scale reactor, performance prediction was also very good. The highest recognition came from production personnel, who believed more in the model than in their instruments. When production performance did not agree with model predictions, they started to check their instruments, rather than questioning the model. 

Failure in the context here means that product performance does not meet requirements and is related back in the design FMEA to some component/character-istic being out of specified limits - a fault. The probability of occurrence of failure (O) caused by a fault can be expressed as ... 

What type of graceful degradation of product performance is desired when portions of the product fail This would determine the type of power busing scheme and power sequencing that may be necessary within the system. 

In general, single tackifiers or blends of tackifiers may be used to formulate to optimum product performance, following the modulus//], criteria outlined... 

In recent years, the use of solvent-borne adhesives has been seriously restricted. Solvents are, in general, volatile, flammable and toxic. Further, solvent may react with other airborne contaminants contributing to smog formation and workplace exposure. These arguments have limited the use of solvent-bome adhesives by different national and European regulations. Although solvent recovery systems and afterburners can be effectively attached to ventilation equipment, many factories are switching to the use of water-borne rubber adhesives, hot melts or 100% solids reactive systems, often at the expense of product performance or labour efficiency. 

Free phenol is a major concern in the manufacture of novolac resins. This is true for several reasons. The strongest drivers are probably EPA classification of phenol as a Hazardous Air Pollutant and worker safety concerns. However, free phenol also has significant technical effects on such parameters as melt flow characteristics. In this role, free phenol may undermine the desired effects of a molecular weight design by increasing flow beyond the desired point. Since free phenol is often variable, the effects on flow may also cause variation in product performance from batch to batch. Fig. 18 shows the effects of free phenol on the flow across a series of molecular weights. Free phenol contents between 1 and 10% are commonly seen. In recent years, much work has been aimed at reducing the free phenol. 

The issues in these evaluations are safety as related to toxicity and flammability, environmental impact as related to the generation of volatile organic compounds and global warming, product performance as related to insulating properties, conformity to fire codes, and the like, cost and availability, and regulatory requirements. 

These long fibres give better product performance although injection moulding machine modifications may be necessary to prevent fibre damage and reduce undesirable fibre orientation effects in the mould. 

Process Parameter—A measurable characteristic of a process that impacts product performance but may not be measured on the product. 

This element ensures that activities such as installation, operation, handling, and servicing also meet quality (ESH/PSM) standards and practices. Feedback systems on product performance are also addressed. 

Press control is critical it is essential that the elastomeric compound reaches the required cure state to optimize product performance yet remains in the press the shortest time period to maximize productivity. To meet this objective, both compression and injection presses now use microprocessor controls, which enable variations in platen temperatures and compound cure characteristics to be accommodated without sacrificing product performance or productivity. 

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