5.1 This test method is particularly useful for quality control tests on thermoplastics.5.2 The data produced by this test method serves to indicate the uniformity of the flow rate of the polymer as made by an individual process. It is not to be used as an indication of uniformity of other properties without valid correlation with data from other tests.5.3 The flow rate obtained with the extrusion plastometer is not a fundamental polymer property. It is an empirically defined parameter critically influenced by the physical properties and molecular structure of the polymer and the conditions of measurement. The rheological characteristics of polymer melts depend on a number of variables. It is possible that the values of these variables occurring in this test will differ substantially from those in large-scale processes, which would result in data that does not correlate directly with processing behavior.5.4 Measure the flow rate of a material using any of the conditions listed for the material in X4.1. For many materials, there are specifications that require the use of this test method, but with some procedural modifications that take precedence when adhering to the specification. Therefore, it is advisable to refer to that material specification before using this test method. Table 1 in Classification D4000 lists the ASTM materials standards that currently exist. An alternative test method for poly (vinyl chloride) (PVC) compounds is found in Test Method D3364.5.5 Additional characterization of a material can be obtained if more than one condition is used. In the case that two or more conditions are employed, a Flow Rate Ratio (FRR) is obtained by dividing the flow rate at one condition by the flow rate at another condition. Procedure D provides one method to measure more than one condition in a single charge.5.6 Frequently, variations in test technique, apparatus geometry, or test conditions, which defy all but the most careful scrutiny, exist, causing discrepancies in flow rate determinations. A troubleshooting guide is found in Appendix X2 and it is a resource to be used to identify sources of test error.1.1 This test method covers the determination of the rate of extrusion of molten thermoplastic resins using an extrusion plastometer.1.2 The values stated in SI units are to be regarded as standard.1.3 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 1: This standard and ISO 1133 address the same subject matter, but differ in technical content.1.4 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 mechanical performance of welded thermoplastic structures is largely dependent on the quality of the welding operation. It is necessary for fabricators to determine that the proper welding procedures are being followed and that welders maintain their proficiency. Results from this practice are indicative of skill in proper welding procedures for different thermoplastic materials and the use of appropriate welding equipment. If the welded test specimens have short term weld factors that meet or exceed the minimums as set forth in this practice, it can be concluded that, with the same degree of skill and diligence by the welder, acceptable welds can be obtained in fabricated structures.1.1 This practice covers the preparation and evaluation of joints between two pieces of weldable grades of thermoplastic materials, backed and unbacked, (such as those shown in Table 1) up to 2 in. (50 mm) in thickness.1.2 Since there are numerous new technologies and techniques constantly being developed for plastic welding, there are no profiles and procedures that can be considered as standard for all plastics at various thicknesses. This practice is not intended to define profiles and procedures; however, it is intended to establish methods to evaluate minimum short term weld factors to be achieved by the welder for the respective plastics.1.3 Weld procedures used for test pieces shall reflect procedures to be used in actual fabrication.1.4 Welding methods to be used include machine welding, extrusion welding, and hot gas welding.1.5 This practice can be utilized by relevant certification bodies to assess welder proficiency and qualification.1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.7 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 1: There is no known ISO equivalent to this standard.1.8 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 Injection Molding—In injection molding, the difference between the dimensions of a mold cavity and of the molded specimen may vary according to the design of the mold and operation of the molding process. Factors such as mold and melt temperature, fill times, and packing conditions are known to affect shrinkage significantly. Adherence to the specified mold design (see 7.1) and specifications outlined in Practice D3641 or ISO 294-4 or the appropriate material specification will improve the reproducibility of the test.5.2 Compression Molding—In compression molding, the difference between the dimensions of a mold cavity and of the molded specimen may vary according to the design of the mold and operation of the molding process. Factors, such as the amount of material in charge, cooling time, and pressure application are known to affect shrinkage significantly. Adherence to the specified mold design (see 7.2) and specifications outlined in Practice D4703 or ISO 293 or the appropriate material specifications will improve the reproducibility of the test.1.1 This test method is intended to measure shrinkage from mold cavity to molded dimensions of thermoplastics when molded by compression or injection processes with specified process conditions.1.2 This test method covers shrinkage measurements at 24 and 48 hours.1.3 This method will give comparable data based on standard specimens and can not predict absolute values in actual molded parts with varying flow paths, wall thicknesses, pressure and temperature gradients and process conditions. Differences in mold shrinkage may also be observed among the three specimen geometries described in this test method.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are given for information only.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.NOTE 1: This standard and ISO 294-3 are equivalent in the design of specimen D2. This test method is equivalent to ISO 294-4 where Type D2 specimens and the procedure in Appendix X2 are used.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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