Test methods history

These latter curves are particularly important when they are obtained experimentally because they are less time consuming and require less specimen preparation than creep curves. Isochronous graphs at several time intervals can also be used to build up creep curves and indicate areas where the main experimental creep programme could be most profitably concentrated. They are also popular as evaluations of deformational behaviour because the data presentation is similar to the conventional tensile test data referred to in Section 2.3. It is interesting to note that the isochronous test method only differs from that of a conventional incremental loading tensile test in that (a) the presence of creep is recognised, and (b) the memory which the material has for its stress history is accounted for by the recovery periods. 

The Canadian Standards Association Standard Z343 (CSA 1998) presents test methods for in-line and firebox flame arresters. In this standard in-line flame arresters are limited to only detonation types and firebox flame arresters are defined as flame arresters installed in an enclosnre, or system of enclosnres, where the mn-np distance is less than 1.5 meters and open to the atmosphere. Firebox flame arresters are commonly nsed on eqnip-ment designed to heat flnids in prodnction operations snch as indirect heaters, emnlsion treaters, and glycol dehydrators. The development history of this standard is presented in Section 2.3.2. 

Groothuizen, Th. M., J. W. Hartgerink, and H. J. Pasman, "Phenomenology, Test Methods, and Case Histories of Explosions in Liquids and Solids," Loss Prev. Safety Prom. Process Ind., 239 (1974). 

Sampling records for any procedure must be complete and should include, but is not restricted to, items relating to the origin of the sample, methods of storage, analytical tests performed, the test methods used, and the analyst(s) who performed the test methods (Table 6.1). In summary, there must be a means to identify the sample history as carefully as possible so that each sample is tracked and defined in terms of source and activity. Thus, the accuracy of the data from any subsequent procedures and tests for which the sample is used will be placed beyond a reasonable doubt. 

If sufficient history is available on a test method, a reaction, or a process, so that the experimental error is known, the test for differences between averages of two sets of data becomes more sensitive. In each of the situations considered above, the form of the equation is the same, but it is no longer necessary to calculate the standard deviation. The symbol Z is used instead of t and the critical value is found in the t table for infinite degrees of freedom This row of the t table corresponds to the table of the normal distribution. 

With the qualitative illustration of observable shock and bubble parameters shown in Fig 5, we can now proceed to a description of the test methods used to obtain such data. Figs 2 5 immediately suggest the use of pressure transducers to follow the pressure-time histories of underwater explns. Similarly Fig 1 (bottom portion) suggests the use of visual (photographic) techniques to obtain dimensions and positions of the gas bubbles. Indeed, these are the major techniques now used in studying underwater shock and bubble effects... 

The results of dynamic tests are dependent on the test conditions test piece shape, mode of deformation, strain amplitude, strain history, frequency and temperature. ISO 4664 gives a good summary of basic factors affecting the choice of test method. Forced vibration, non-resonant tests in simple shear using a sinusoidal waveform are generally preferred for design data as... 

The book collates the many standard methods, comments on their virtues and defects and considers procedures needed for both quality control and the generation of design data. The content owes much to the experience gained due to Rapra s position over many decades as an international centre for rubber research, as a test house with a history of developing test procedures and making a very significant contribution to national and international standardisation. The literature relating to the development and application of rubber test methods has also been reviewed. 

However, we should keep in mind that in spite of a long history of testing we have been unable to foresee the environmental hazards of many anthropogenic substances, such as DDT, PCB, chlorinated paraffins, brominated flame retardants, PFOS and lately the pharmaceutical drug diclophenac (Oaks et al. 2004). Mankind and the environment pay a high price for these mistakes and we have to do a better job in the future. So the new challenge is When we replace one test method with a new one, it should not just be as good but better than what we have used before. 

Batch Record IQA (1994) Documents (including those stored in photographic and electronic form) that record stages in the manufacture of a batch, details of ingredients and process equipment used, methods followed, in-process controls carried out, test results obtained, dates of manufacture, and testing and history of the storage of the pharmaceutical raw material. 

Another significant event in the history of plastics standards was the first meeting of Technical Committee 61 on Plastics of the International Organization for Standardization in New York on September 8 and 9, 1951. Representatives from Australia, France, the Netherlands, Sweden, Switzerland, the United Kingdom, and the United States met to consider the establishment of testing methods and nomenclature for international use. The second meeting of ISO/TC 61 on Plastics was held in Turin, Italy, on October 2 to 4, 1952, and it is anticipated that this committee in the near future will be ready to recommend the first international testing methods on plastics to the member standards bodies of the various countries. 

The need for Improved prediction capabilities Is addressed by (1) Investigating the relationship between present properties of a material, the history of these properties, and the future performance of the material by (2) developing short-term measurement and test methods to forecast the long-term performance of materials, and by (3) constructing basic models for predicting lifetime performance of materials. 

The pour point (ASTM D-97, IP 15) is the lowest temperature at which the fuel oil will flow under specified conditions. The maximum and minimum pour point temperatures provide a temperature window where a petroleum product, depending on its thermal history, might appear in the liquid as well as the solid state. Pour point data can be used to supplement other measurements of cold flow behavior, and the data are particularly useful for the screening of the effect of wax interaction modifiers on the flow behavior of petroleum. The pour point should not be confused with the freezing point, which is an index of the lowest temperature at which the crude oil will flow under specified conditions. Test methods (ASTM D-2386, ASTM D-5901, ASTM D-5972, IP 434, IP 435) for the freezing point are not usually applicable to fuel oil but are more applicable to diesel fuel and aviation fuel. 

There are two sources of interferences in this test method—moisture and particle size. Moisture increases the mass loss, the moisture-free sample weight is decreased by the amount of moisture actually present in the test sample, and the particle size range of the analysis sample affects the volatile matter. The coarser the sample, the lower the reported yield of volatile matter. The method is not satisfactory for determining the content of dust control material, and samples with a thermal history above 600°C (1112°F) are excluded from this test. 

The way in which testing methods keep in touch with changing market patterns is illustrated by excerpts taken from the history of the original process for making activated carbon in America. The source material for that process was black-ash residue, a waste product from the manufacture of soda pulp. Although this early activated carbon had much less adsorptive power than brands of today, it was found useful for decolorizing coconut oil, phosphoric acid, and other industrial products. Complaints were received from customers stating that the quality was uneven, and as these complaints became more frequent it was necessary to institute quality controls. 

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