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5.1 This practice is used as a basis for determining the minimum ground-based octane requirement of turbocharged/supercharged aircraft engines by use of PRFs and RFs.5.2 Results from standardized octane ratings will play an important role in defining the octane requirement of a given aircraft engine, which can be applied in an effort to determine a fleet requirement.1.1 This practice covers ground-based octane rating procedures for turbocharged/supercharged spark ignition aircraft engines. This practice has been developed to allow the widest range of applicability possible but may not be appropriate for all engine types. This practice is specifically directed to ground-based testing and actual in-flight octane ratings may produce significantly different results.1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The procedure for establishing the long-term pressure rating of fittings starts with an extrapolation of a regression line that is based on fitting failure data with respect to time, when assemblies are tested in accordance with Test Method D1598. The pressure-versus time to failure data are obtained using water at 73 °F in assemblies that are immersed in a water or air environment. The extrapolation is made in such a manner that the long-term hydrostatic pressure rating is determined for these conditions.4.2 The pressure design basis is determined by considering the following items and evaluating them in accordance with 6.3.4.2.1 Long-term hydrostatic pressure-strength at 100 000 h,4.2.2 Long-term hydrostatic pressure-strength at 50 years4.3 The fitting pressure rating may be calculated by multiplying the pressure design basis (PDB) by the appropriate design factor (DF).1.1 This test method covers a procedure for establishing Pressure Rating for PVC schedule 40 and 80 socket-type fittings by evaluating fitting failure test data derived by testing water-filled assemblies of pipe and fittings.1.2 Unless the data approximates a straight line, when calculated using log-log coordinates, it is not possible to assign a pressure rating to that product or sample of product. Data that exhibit high scatter, or a downward curve, due to low long term data, will give low extrapolated values that are more conservative when calculated using log-log co-ordinates. In addition, this downward curve will show as higher scatter, and where the lower confidence level limits are not met the data shall be classified as unsuitable. (See Note 1)NOTE 1: This test method is similar to that used in Test Method D2837, which has been used for about 30 years to establish the HDS of plastic pipe materials and is the basis for all pressure ratings assigned to plastic pipes.1.3 The products covered by this test method are schedule 40 or 80 molded PVC fittings that conform to Specifications D2466 or D2467.1.4 The pressure ratings developed using this test method applies only to fittings identical to the ones that were tested. Some variables that will affect the pressure rating are – pipe size, pattern, mold design, material, and molding conditions.1.5 The values in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.6 The testing procedure used to obtain the fitting failure data shall be as described in those sections of Test Method D1598, that are referenced in Section 6 of this test method.1.7 The products covered by this test method are intended for use in the distribution of pressurized liquids at 73 °F. When appropriate, the design engineer must consider the effects of elevated temperature and chemical compatibility of the liquid with the fitting material and apply necessary design factors.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.NOTE 2: Pressurized (compressed) air or other compressed gases contain large amounts of stored energy which present serious safety hazards should a system fail for any reason.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Coil-coated metals are subjected to a wide range of environmental stresses. Corrosion at cut edges, damage points, and fabricated areas can occur and lead to premature failure. Proper preparation and rating of test panels produces meaningful test results that allows comparisons between metal substrates and their pretreatments as well as between coating systems.5.2 Laboratory-prepared test panels give a relative comparison of the substrates and coating systems under test, but may not duplicate all of the stresses imposed on manufactured components. Validation of results on a manufactured product is recommended.5.3 Laboratory accelerated corrosion testing is useful in evaluating relative performance of new and existing metal coatings, pretreatments, and paints. It is up to the participating parties to agree on the significance of these tests to actual use.1.1 This guide has been written specifically for coil-coated metal building products.1.2 This guide applies to preparation, testing, and rating of line-coated and laboratory-coated test panels for the purpose of comparing and ranking the panels for corrosion resistance and other related properties.1.3 Testing may include accelerated laboratory corrosion tests and outdoor exposure tests.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The microstructure and grain growth of cemented tungsten carbides affect the material's mechanical and physical properties. The grain size and distribution will affect the material's wear resistance and fracture toughness. Abnormally large grains as compared to the background may introduce an area of weakness in a sintered part.5.2 This test method may be used in acceptance testing of cemented tungsten carbide materials or the tungsten carbide powder used in their manufacture. The specified grain size used for the E-Rating is to be agreed upon between purchaser and supplier.1.1 This test method describes a procedure for measuring abnormally large grains and the frequency of those grains in cemented tungsten carbides (hardmetals).1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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