Iso 1133 astm d1238 差异. ASTM

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NORMA ISO 1133 i ASTM

iso 1133 astm d1238 差异

Cleaning the components of the test machine must be done after every test. The furnace of the instrument, which contains a heated metal cylinder with a defined bore, should be leveled using equipment typically supplied by the equipment manufacturer. The die should be visually inspected to make sure that the entrance of the bore is not chipped or rounded. Resin suppliers generally post their test conditions along with reported test values. The piston foot is required to reach that point within 420 ± 30 sec after the material charging has been completed.

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NORMA ISO 1133 i ASTM

iso 1133 astm d1238 差异

In theory, both methods, if properly performed, will yield identical test results. If you are suspicious of the melt-flow data you are obtaining, you have plenty of options for checking and updating equipment, examining procedures, and comparing results with those obtained by others. Clean the barrel by repeated swabbing with a cotton cleaning patch using tools normally provided by the equipment manufacturer. Es más, no seleccionamos la mayoría de los publicistas ni los anuncios publicitarios que aparecen en el sitio web. Extrudate cutting technique can be a factor in Procedure A tests. A timed extrudate is collected and weighed.

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Melt Flow Rate ASTM D 1238, ISO 1133

iso 1133 astm d1238 差异

For Procedure B tests, permissible piston travel distances are 6. No debe ser usado como un sustituto o suplencia de una consulta médica profesional, diagnóstico o tratamiento. Is the melt indexer in good working order? It is also important to note that the first cut starting at 46 ± 2 mm is considered to be the reportable test result. A variety of factors affect the precision and accuracy of a test. It is important that comparative tests are performed using the same test conditions.

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Melt Flow Rate ASTM D 1238, ISO 1133

iso 1133 astm d1238 差异

A spatula or similar tool is used to cut material as it extrudes from the die at precise intervals. The practice of making successive cuts and averaging them together should be avoided. Sin embargo, este procedimiento requiere un valor preciso para la densidad de masa fundida de resina a la temperatura de ensayo, mientras que el procedimiento A no requiere de este conocimiento. The verification procedure will check the dimensions of the machine, as well as the temperature-control and distance-measuring devices installed on the machine, for conformance to the relevant test standard. Whether your business is local or global, we can ensure your products meet quality, health, environmental, safety, and social accountability standards for virtually any market around the world.

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ASTM

iso 1133 astm d1238 差异

Also measure the foot diameter with a micrometer: It should be 9. Standards can be obtained from appropriate standard authorities. By being aware of each one, adhering closely to test procedures, maintaining your equipment, and following good overall testing practices, you can improve accuracy and keep small problems from growing into larger ones. The equipment should be located in an area free from vibration and excessive air currents. Both offer a manual means Procedure A or Method A and automatic timed-flow measurement Procedure B or Method B. Cada norma especifica la longitud y el diámetro del orificio, la temperatura del barril y las clasificaciones del pistón de carga. Biografia: By Harry Yohn from Tinius Olsen Testing Machine Co.

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ASTM

iso 1133 astm d1238 差异

No matter what the procedure selected, it is common for two organizations to test the same material and come up with two different test results, setting off a search to determine the reason for the difference. The melt density is a multiplier that converts volume back into a mass value. It provides a means of measuring flow of a melted material which can be used to differentiate grades as with polyethylene, or determine the extent of degradation of the plastic as a result of molding. Procedure B requires the use of a melt-density value, which is the density of the material when it is in its molten state. The diameter of the bore, defined in D1238 as 2. Automatic cutters can be useful but may not work with all materials.

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NORMA ISO 1133 i ASTM

iso 1133 astm d1238 差异

A properly performed test begins when the bottom of the piston foot is 46 ± 2 mm from the top of die. Using a tool to pack material into the bore during the charging process is common practice, but it can result in variable test results for some materials if multiple machine operators are involved, because they commonly use different amounts of force to pack the material. A preferable alternative to packing the material or purging is to use trial and error to determine the optimum amount of material to be charged in the bore based on the expected flow rate, which will result in the test starting at the proper time. These factors will change with additives and processing, so it is more accurate to measure the actual melt density of the specific resin being tested. Practices like these are useful in that they can point out when there is something wrong. Variations in sample mass and sample charging technique can affect test results of some materials. To meet the preheat and test start-time requirements, it may be necessary to unload the test load from the piston or stop its travel during the preheat period.

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Melt Flow Rate ASTM D 1238, ISO 1133

iso 1133 astm d1238 差异

Inc From: Plastics Technology Issue: September 2011. Extra care must be used when dealing with high-flow materials to avoid burns. A preheat time is required to remove trapped air and ensure that the material is sufficiently and evenly melted, and that the temperature of the material in the bore stabilizes to within ±0. Test conditions for temperature and load vary by material. Prior to running any tests, visually inspect all components of the testing machine. No residue from prior tests should remain on the surfaces of the metal parts directly involved in the test.

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[图文]塑料物性检测标准ISO ASTM DIN 对比

iso 1133 astm d1238 差异

Por lo general, el procedimiento B produce mediciones más precisas, ya que tiene menos oportunidades de interferencia del usuario. Typically, flow rates for a part and the resin it is molded from are determined, and then a percentage difference is calculated. The operator selects the distance based on the expected flow rate. Some labs maintain their own supply of reference material, which they use to maintain in-house quality programs. Keeping enough material in the bore can be just as challenging for materials with higher flow rates.

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