5.1 The incorporation of fillers into the rubber matrix is characterized by their macrodispersion as an indicator of the quality of mixing. This test method provides a measure of the macro-dispersion of reinforcing fillers, like silica and carbon black, as well as of inert fillers. Based on their polymer nature, different types of rubbers can show a different degree of acceptance for the incorporation of fillers, as indicated by their macro-dispersion.5.2 Macro-dispersion of carbon black and silica in rubber compounds may be measured by different methods. Carbon black provides a direct physical reinforcement; silica requires a silane coupling agent in order to initiate reinforcement, and therefore, a different technology of mixing. Silica is also a non-conductor, making electrical methods of dispersion measurement impracticable. This test method is specifically appropriate for the characterization of the microdispersion in silica technology.5.3 This test method also can measure the mixing quality of colored rubbers. It uses variable exposure in order to be able to image a wide range of colors.5.4 This test method is intended for use in research and development as well as in quality control of filler processability in rubber and may be used for both the evaluation of production processes or referee purposes.1.1 This test method covers a procedure to measure the macro-dispersion of fillers in a rubber matrix by quantifying the surface roughness of a freshly cut specimen using an optical microscope in reflection mode.1.2 The method provides a procedure to measure the quality of mixing of reinforcing fillers such as silica and carbon black, as well as inert fillers such as chalk, clay and other solids.1.3 The method includes a sample preparation procedure for filled uncured rubber compounds as well as filled cured rubber compounds.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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3.1 This test method is intended to determine the pour point of petroleum oils used in the softening and stuffing of leather, as well as those used in the manufacture of products for such purpose. The pour point of petroleum oils is measured for the purpose of quality assurance.1.1 This test method covers the determination of the pour point of petroleum oils used in the softening and stuffing of leather, and in the manufacture of fatliquors and other softening and stuffing compounds. This test method was derived from Test Method D97 and ALCA Method H-18.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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.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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4.1 This test method is useful to both producers and purchasers of powders, as outlined in 1.1 and 1.2, in determining particle size distribution for product specifications, manufacturing control, development, and research. 4.2 Users should be aware that sample concentrations used in this test method may not be what is considered ideal by some authorities, and that the range of this test method extends into the region where Brownian movement could be a factor in conventional sedimentation. Within the range of this test method, neither the sample concentration nor Brownian movement are believed to be significant. 4.3 Reported particle size measurement is a function of both the actual particle dimension and shape factor as well as the particular physical or chemical properties being measured. Caution is required when comparing data from instruments operating on different physical or chemical parameters or with different particle size measurement ranges. Sample acquisition, handling, and preparation can also affect reported particle size results. 1.1 This test method covers the determination of particle size distributions of metal powders. Experience has shown that this test method is satisfactory for the analysis of elemental tungsten, tungsten carbide, molybdenum, and tantalum powders, all with an as-supplied estimated average particle size of 6 μm or less, as determined by Test Method B330. Other metal powders (for example, elemental metals, carbides, and nitrides) may be analyzed using this test method with caution as to significance until actual satisfactory experience is developed (see 7.2). The procedure covers the determination of particle size distribution of the powder in the following two conditions: 1.1.1 As the powder is supplied (as-supplied), and 1.1.2 After the powder has been deagglomerated by rod milling as described in Practice B859. 1.2 This test method is applicable to particles of uniform density and composition having a particle size distribution range of 0.1 up to 100 μm. 1.2.1 However, the relationship between size and sedimentation velocity used in this test method assumes that particles sediment within the laminar flow regime. This requires that the particles sediment with a Reynolds number of 0.3 or less. Particle size distribution analysis for particles settling with a larger Reynolds number may be incorrect due to turbulent flow. Some materials covered by this test method may settle with Reynolds number greater than 0.3 if particles greater than 25 μm are present. The user of this test method should calculate the Reynolds number of the largest particle expected to be present in order to judge the quality of obtained results. Reynolds number (Re) can be calculated using the flowing equation where D   =   the diameter of the largest particle expected to be present, ρ   =   the particle density, ρ0   =   the suspending liquid density, g   =   the acceleration due to gravity, and η   =   is the suspending liquid viscosity. A table of the largest particles that can be analyzed with Reynolds number of 0.3 or less in water at 35°C is given for a number of metals in Table 1. A column of the Reynolds number calculated for a 30–μm particle sedimenting in the same liquid system is given for each material also. 1.3 Units—With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm3) and gram (g) units is the longstanding industry practice, the values in SI units are to be regarded as standard. 1.4 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. Specific hazard information is given in Section 7. 1.5 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 Cable filling and flooding compounds are normally semi-solid at room temperature and fluid in varying degrees at elevated temperatures. They are normally applied in a liquid state and at an elevated temperature during wire and cable manufacturing. The completed finished wire or cable is exposed to various ambient conditions during its useful life. If not carefully selected, components of filling or flooding compounds have the potential to degrade the materials they contact, short term or long term. The following methods are intended to minimize the chances of such problems occurring.4.2 Some of the effects that might occur include, but are not limited to:4.2.1 Delamination of coated metal shields or screens in completed wire and cable. Delamination is primarily a function of the test temperature and the type of laminant used, so test results are unlikely to vary significantly between filling or flooding compounds of a common family (for example, petroleum based filling or flooding compounds).4.2.2 Degradation of physical properties of insulation, jackets, core coverings, etc. Likely manifestations of degradation of plastic material include embrittlement of some materials and excessive softening of other materials.4.3 Since the magnitude of any given effect will vary, some test procedures will be more critical than others. It is not, therefore, intended that every listed procedure be performed with every compatibility study. Perform procedures to the extent required by product specifications or as agreed upon between the producer and the purchaser.1.1 These test methods evaluate the compatibility between cable filling or cable flooding compounds, or both, and polyolefin materials used in the manufacture of wire and cable that are usually in intimate contact with the filler or floodant, or both.1.2 These test methods are useful to ensure compatibility and to verify that new formulations of filling or flooding compounds will have no deleterious effect upon the other polyolefin materials being used or, conversely, use these methods to ensure that other polyolefin wire and cable materials are evaluated for possible use not degraded by contact with fillers or floodants already in use.1.3 Whenever two sets of values are presented, in different units, the values in the first set are to be regarded as standard. The values given in parentheses are mathematical conversions that are provided for information only and are not considered standard.1.4 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.1.5 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 Wipe sampling is typically used by persons involved in hazardous waste site investigations to characterize the areal extent and the level of contamination on walls, floors, equipment, etc. Wipe sampling is also used to determine compliance with regulations.5.2 There are many factors that contribute to variation in sampling results during wipe sampling, including the use of different pressures applied to the wipe, different kinds of wipes, different wiping patterns, the texture of the surface being wiped, and perhaps even the duration of wiping. The significance of this practice is that it standardizes wiping procedures to reduce sampling variability in the collection of samples from smooth, nonporous surfaces such as metal, glass, painted or sealed surfaces, tile, etc., in and around buildings and from pipes, tanks, decontaminated equipment, etc.1.1 This practice addresses sampling of organic compounds (that is, PCBs, dioxins, many pesticides and similar compounds) from smooth nonporous surfaces using a solvent-wetted wipe sampling method. Samples are collected in a manner that permits the solvent extraction of the organic compound(s) of interest from the wipes and subsequent determination using a laboratory analysis technique such as gas chromatography with a suitable detector. This practice is, however, unsuitable for the collection of volatile organic compounds.1.2 This practice should only be used to collect samples for the determination of organic compound(s) on a loading basis (for example, mass per unit area). It cannot be used to collect samples for the determination of organic compounds on a concentration basis (for example, mass per unit mass).1.3 This wipe sampling practice is not recommended for collecting samples of organic compounds from rough or porous surfaces such as upholstery, carpeting, brick, rough concrete, ceiling tiles, and bare wood. It is also not intended for the collection of dust samples (see Guide E1278) or sampling to estimate human exposure to contaminated surfaces.1.4 To ensure valid conclusions are reached, a sufficient number of samples must be obtained as directed by a sampling design (the number and location of samples including quality control samples) and a quality assurance/quality control plan. This practice does not address the sampling designs used to achieve the data quality objectives (see Practice D5792).1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 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.1.7 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 This field test method determines the mass concentration of VOHAPs (or any subset) listed in Section 1.5.2 Multiplying the mass concentration by the effluent volumetric flow rate (see 2.2) yields mass emission rates.5.3 This field test method employs laboratory GCMS techniques and QA/quality control (QC) procedures in common application.5.4 This field test method provides data with accuracy and precision similar to most laboratory GCMS instrumentation.1.1 This test method employs a direct interface gas chromatograph/mass spectrometer (GCMS) to identify and quantify the 36 volatile organic compounds (or sub-set of these compounds) listed as follows. The individual Chemical Abstract Service (CAS) numbers are listed after each compound.Benzene-71432 Methylene chloride-75092Bromodichloromethane-75274 1,1,2,2-Tetrachloroethane-79349Carbon disulfide-75150 1,1,1-Trichloroethane-71556Chloroform-67663 1,1,2-Trichloroethane-79005Methyl iso-Butyl ketone-108101 p-Xylene-106423Styrene-100425 Bromomethane-74839Tetrachloroethylene-127184 Carbon tetrachloride-56235Toluene-108883 Chlorobenzene-108907Bromoform-75252 c-1,3-Dichloropropene-10061015Vinyl acetate-108054 1,2-Dichloroethane-156592Vinyl chloride-75014 1,1-Dichloroethene-75354Chloromethane-74873 t-1,2-Dichloroethene-156605cis-1,2-Dichloroethene-156592 Methyl ethyl ketone-78933Dibromochloromethane-124481 2-Hexanone-5917861,1-Dichloroethane-107062 t-1,3-Dichloropropene-5427561,2-Dichloropropane-78875 Trichloroethene-79016Ethylbenzene-100414 m-Xylene-108383Ethyl chloride-75003 o-Xylene-954761.2 The test method incorporates a performance-based approach, which validates each GCMS analysis by placing boundaries on the instrument response to gaseous internal standards and their specific mass spectral relative abundance. Using this approach, the test method may be extended to analyze other compounds.1.3 The test method provides on-site analysis of extracted, unconditioned, and unsaturated (at the instrument) gas samples from stationary sources. Gas streams with high moisture content may require conditioning to prevent moisture condensation within the instrument. For these samples, quality assurance (QA) requirements are provided in the test method to validate the analysis of polar, water-soluble compounds.1.4 The instrument range should be sufficient to measure the listed volatile organic compounds from 150 ppb(v) to 100 ppm(v), using a full scan operation (between 45 and 300 atomic mass units). The range may be extended to higher or lower concentrations using either of the following procedures:1.4.1 The initial three-point calibration concentrations and the continuing calibration checks are adjusted to match the stack concentrations, or1.4.2 The three-point calibration is extended to include additional concentrations to cover the measurement range.1.5 The minimum quantification level is 50 % of the lowest calibration concentration. Responses below this level are considered to be estimated concentrations, unless a calibration standard check is conducted at a lower concentration to demonstrate linearity. The sensitivity of the GCMS measurement system for the individual target analytes depends upon:1.5.1 The specific instrument response for each target analyte and the number of mass spectral quantification ions available.1.5.2 The amount of instrument noise, and1.5.3 The percent moisture content of the sample gas.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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. Additional safety precautions are described in Section 9.1.8 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 Compliance with national and local air emission regulations create the need to determine volatile organic compound (VOC) emissions from adhesive-bonded structural wood products.5.2 This method has been used to estimate the types and amounts of certain VOC that are emitted during production operations.5.3 The method was originally developed to measure the methanol, formaldehyde, and phenol emitted in a laboratory setting that is designed to simulate the hot pressing, and post pressing conditions of hot stacking and cool down period for exterior plywood and laminated veneer lumber (LVL) processes. This current method generalizes the concept for adhesive-bonded wood products.1.1 This test method provides a method for the collection of volatile organic compounds (VOC) that are emitted during the manufacture of engineered wood products using a laboratory environment designed to simulate a defined production process. The method is used for the determination of the amounts of methanol, formaldehyde, phenol and other VOC that may be emitted during conditions designed to simulate production such as hot pressing, the conditions of ‘hot stacking’ and ‘cool-down’ that occurs post-press.1.2 The test method was originally developed to measure certain VOC from exterior plywood meeting Voluntary Product Standard PS 1–09 and structural composite lumber products such as laminated veneer lumber (LVL) meeting Specification D5456. Both of these product types are typically manufactured using phenol-formaldehyde resin based adhesives that meet Specification D2559.1.3 The test method is suitable for many types of wood products bonded with adhesives.1.4 This test method is specific for collecting VOC during simulated production of wood products and is not designed to determine general organic emissions from all indoor materials or sources.1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.1.6 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. Some specific hazards statements are given in Section 7 on Hazards.1.7 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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This specification covers the design requirements of each component and basic equipment comprising the apparatus used for the microdetermination of carbon and hydrogen in organic and organometallic compounds along the lines of the conventional method of Pregl, but with modifications more in line with modern practice. Due to the diversity of this apparatus by which correct results can be obtained, this specification is intended to indicate what is acceptable rather than what is mandatory. The components covered here are the oxygen supply, pressure, regulator, drying and purifying tube, flowmeter, combustion unit, absorption tubes, guard tube, Mariotte bottle, and weighing accessories.1.1 This specification covers apparatus and basic equipment for the determination of carbon and hydrogen in organic and organometallic compounds along the lines of the conventional method of Pregl, but with modifications more in line with modern practice. Owing to the diversity of apparatus by which correct results can be obtained, this specification is intended to indicate what is acceptable rather than what is mandatory.NOTE 1: Specifications for several items subsequently listed were developed by the Committee for the Standardization of Microchemical Apparatus, Division of Analytical Chemistry, American Chemical Society.21.2 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.

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5.1 Gaseous fuels, such as natural gas, petroleum gases and bio-gases, contain sulfur compounds that are naturally occurring or that are added as odorants for safety purposes. These sulfur compounds are odorous, toxic, corrosive to equipment, and can inhibit or destroy catalysts employed in gas processing and other end uses. Their accurate continuous measurement is important to gas processing, operation and use, and is frequently of regulatory interest.5.2 Small amounts (typically, total of 4 to 6 ppm(v)) of sulfur odorants are added to natural gas and other fuel gases for safety purposes. Some sulfur odorants are reactive and may be oxidized to form more stable sulfur compounds having higher odor thresholds which adversely impact the potential safety of the gas delivery systems and gas users. Gaseous fuels are analyzed for sulfur compounds and odorant levels to assist in pipeline integrity surveillance and to ensure appropriate odorant levels for public safety.5.3 This method offers an on-line method to continuously identify and quantify individual target sulfur species in gaseous fuel with automatic calibration and validation.1.1 This test method is for on-line measurement of gas phase sulfur-containing compounds in gaseous fuels by gas chromatography (GC) and electrochemical (EC) detection. This test method is applicable to hydrogen sulfide, C1 to C4 mercaptans, sulfides, and tetrahydrothiophene (THT).1.1.1 Carbonyl sulfide (COS) is not measured according to this test method.1.1.2 The detection range for sulfur compounds is approximately from 0.1 to 100 ppm(v) (mL/m3) or 0.1 to 100 mg/m3 at 25 °C, 101.3 kPa. The detection range will vary depending on the sample injection volume, chromatographic peak separation, and the sensitivity of the specific EC detector.1.2 This test method describes a GC-EC method using capillary GC columns and a specific detector for natural gas and other gaseous fuels composed of mainly light (C4 and smaller) hydrocarbons. Alternative GC columns including packed columns, detector designs, and instrument parameters may be used, provided that chromatographic separation, quality control, and measurement objectives needed to comply with user or regulator needs, or both, are achieved.1.3 This test method does not intend to identify and measure all individual sulfur species and is mainly employed for monitoring naturally occurring reduced sulfur compounds commonly found in natural gas and fuel gases or employed as an odorant in these gases.1.4 This test method is typically employed in repetitive or continuous on-line monitoring of sulfur components in natural gas and fuel gases using a single sulfur calibration standard. Guidance for producing calibration curves specific to particular analytes or enhanced quality control procedures can be found in Test Methods D5504, D5623, D6228, D6968, ISO 19739, or GPA 2199.1.5 The test method can be used for measuring sulfur compounds listed in Table 1 in air or other gaseous matrices, provided that compounds that can interfere with the GC separation and electrochemical detection are not present.1.6 This test method is written as a companion to Practices D5287, D7165 and D7166.1.7 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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.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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4.1 The spiral flow of a thermosetting molding compound is a measure of the combined characteristics of fusion under pressure, melt viscosity, and gelation rate under specific conditions.4.2 This test method is useful as a quality control test and as an acceptance criterion.4.3 This test method, by itself, is not a valid means for comparing the moldability of similar or different molding compounds because it cannot duplicate actual conditions prevalent in different types of production molds.4.4 This test method is presently intended for use at a transfer pressure of 6.9 MPa (1000 psi) and a mold temperature of 423 ± 3 K (150 ± 3°C (302 ± 5°F)).1.1 This test method covers a procedure for measuring the spiral flow of thermosetting molding compounds (soft or very soft) designed for molding pressures under 6.9 MPa (1000 psi). It is especially suited for those compounds used for encapsulation or other low pressure molding techniques. It involves the use of a standard spiral flow mold in a transfer molding press under specified conditions of applied temperature and pressure with a controlled charge mass.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 and health practices and determine the applicability of regulatory limitations prior to use.NOTE 1: There is no known ISO equivalent to this test method.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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4.1 This test method covers the evaluation of the tap density physical characteristic of metal powders and related compounds. The measured tap density bears a relationship to the mass of powder that will fill a fixed volume die cavity or other container in situations where the container is tapped, vibrated, or otherwise agitated. The degree of correlation between the results of this test method and the quality of powders in use will vary with each particular application and has not been fully determined.1.1 This test method specifies a method for the determination of tap density (packed density) of metal powders and compounds, that is, the density of a powder that has been tapped, to settle contents, in a container under specified conditions.1.2 Units—With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm3) and gram (g) units is the long-standing industry practice, the values 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.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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4.1 The moisture retaining ability of a product as determined by this test method is used to assess the suitability of materials for contributing to an appropriate curing environment for concrete. The laboratory test method is used both in formulating and in specifying or qualifying curing products. This test method gives the user a measure of the ability of tested curing materials to impede the escape of water from a hydraulic cement mortar. Since it is desirable to retain water in fresh concrete to promote the hydration process, failure of the product to minimize the escape of water may lead to loss of strength, cracking, shrinkage, or low abrasion resistance of the hardened concrete, or a combination thereof.4.2 Many factors affect the laboratory test results. Test results obtained may be highly variable as indicated by the precision statement. Critical factors include the precision of the control of the temperature, humidity and air circulation in the curing cabinet, preparation and sealing of the mortar specimens, the age and surface condition of the mortar specimen when the curing product is applied, and the uniformity and quantity of application of the curing membrane.1.1 This test method covers laboratory determination of the ability of liquid membrane-forming compounds for curing concrete to reduce moisture loss from mortar specimens during the early hardening period as a measure of their applicability for curing concrete.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.)21.4 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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1.1 These practices cover procedures for the identification, selection, and application of oil- and resin-based putty and glazing compounds, in glazing installations. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 This practice is subject to the definition of injection molding given in 3.1.2 with the further provision that with in-line screw injection the plastic compound, heated in a chamber by conduction and friction, is fluxed by the action of a reciprocating screw and then is forced into a hot mold where it solidifies. Hereafter, in-line screw-injection molding will be referred to simply as injection molding.4.2 The mold referenced in this section (see Fig. 1) is generally useful, and describes what have been the most common specimens required for the testing of thermosets. ISO specimens and testing are gaining favor, however. Practice D3641 and ISO 10724 describe the layout and practice for injection molding the multi-purpose specimens in accordance with ISO 3167.FIG. 1 Five-Cavity Transfer Mold for Thermosetting Plastic Test Specimens (Steam Cores Not Shown)NOTE 1: Thermometer wells shall be 8 mm (5/16 in.) in diameter to permit use of a readily available thermometer.4.3 Typically, injection-molded test specimens are made with shorter cycles than those used for similar moldings made by compression, and the cycle is equal to or faster than that for transfer molding.4.4 Breathing of the mold is not usually required to release trapped volatile material as the gas is free to flow from the vent end of the mold. This is particularly advantageous for heat-resistant compounds and reduces the tendency for molded specimens to blister at high exposure temperatures.4.5 Injection molding is intended for low-viscosity compounds. One set of processing parameters cannot be specified for all types of thermosetting materials, nor for samples of the same material having different plasticities.4.6 Materials containing fibrous fillers such as glass roving, chopped cloth, or cellulosic fibers can be injection molded, but their properties will be affected depending upon how much fiber breakdown occurs as the compound is worked by the screw and as it passes through the system of runners and gates. The orientation of the fibers in the molded specimen will also affect injection-molded properties.4.7 Flow and knit lines in a molded piece are often sites of mechanical or electrical weakness. The fluxed material passing through the gate wrinkles and folds as it proceeds into the mold cavity. Knit lines are found to some degree throughout the molded piece; and can affect test results. Fibers and other reinforcements in the molding compound align with the flow pattern and, generally, are perpendicular to the axis of the bar at its center and parallel at its surface.4.7.1 Placement and size of gates and vents can be used to minimize flow and knit lines, for example, side gating of bars will minimize the tendency of the material to fold onto itself as the material front proceeds through the length of the mold.4.8 The Izod impact strength of injection-molded specimens containing short fibers will generally be lower than the values obtained using compression molding methods. The impact strength can also vary along the axis of the bar due to molding parameters, flow patterns, and fiber orientation.4.9 The flexural and tensile strength of injection-molded specimens of molding compounds containing short fibers will generally be higher than the values obtained using compression-molding methods. Flexural tests are particularly sensitive to injection molding due to the thin resin skin formed at the surface of the bar during final filling of the cavity and pressure buildup.4.10 At constant mold temperature the following parameters are known to cause an underfilled condition at the vented end of the cavity: incorrect plasticity, too low an injection pressure, insufficient material, too long an injection time, blocked vents, high stock temperature, or incorrect die temperature.1.1 This practice covers the general principles to be followed when injection molding test specimens of thermosetting materials. It is to be used to obtain uniformity in methods of describing the various steps of the injection molding process and in the reporting of those conditions. The exact molding conditions will vary from material to material, and if not incorporated in the material specification, shall be agreed upon between the purchaser and the supplier or determined by previous experience with the particular type of material being used and its plasticity.NOTE 1: The utility of this practice has been demonstrated for the molding of thermosetting molding compounds exhibiting lower-viscosity non-Newtonian flow.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.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.1.4 This practice assumes the use of reciprocating screw injection molding machines.NOTE 2: This standard and ISO 10724 address the same subject matter, but differ in technical content.1.5 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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