NOTIZIA

16 novembre

Metodo di prova standard ASTM D1149-2018 per la rottura e la fessurazione della gomma in ambienti controllati dall'ozono

Significato e uso 4.1 L'importanza di questi metodi di prova risiede nella capacità di distinguere il grado di resistenza all'ozono in condizioni limitate e specifiche di test accelerati. Il grado di resistenza viene giudicato dall'aspetto e dalla dimensione delle crepe formate sulla superficie del materiale sottoposto a prova. 4.2 In uso, i materiali in gomma si deteriorano se esposti all'ozono. È necessario che esista un metodo di prova semplice, tempo/esposizione accelerato, comparing the ability of the material to resist [...]

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16 novembre

ASTM D1248-2016 Standard Specification for Polyethylene Plastic Extruded Materials for Wire and Cable

The code specifies the identification of polyethylene plastic extrusion materials for wire and cable so that sellers and buyers can agree on the acceptability of different commercial batches or shipments. Polyethylene plastics are primarily identified based on two characteristics, namely density and flow rate (formerly known as melt index). The former is the criteria for type assignment as follows: Tipo 0, Type I, Type II, Type III, and type IV, while the latter is used to specify categories, namely: [...]

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14 novembre

ASTM D4279-2017 Standard Test Method for Water Vapor Transmission in Transportation Vessels – Constant and Cyclic Methods

Significato e uso 4.1 These test methods are generally used for the following purposes: 4.1.1 To evaluate the materials and construction of a particular type of container, 4.1.2 To compare the performance of different types of containers, 4.1.3 Determine whether the protection of a particular product or application is adequate, e 4.1.4 Maintain quality control. ASTM D4279-2017 Standard Test Method for Water Vapor Transmission in Transportation Vessels – Constant and Cyclic Methods Step 1: Scopo 1.1 These test methods cover the determination of the water vapor transmittance [...]

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14 novembre

ASTM D4169-2016 Specifiche standard per i test prestazionali di contenitori e sistemi di spedizione

Significato e uso 4.1 The practice provides guidance for evaluating transport units using a uniform system and using established test methods to represent the levels in the actual distribution. Recommended testing levels are based on available information about the shipping and loading and unloading environment and current industry/government practices and experience (1-13). 6 Tests shall be performed on the same containers in the given order. To be used as a performance test, this practice requires that the transport unit under [...]

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14 novembre

ASTM D3654/D3654M-2019 Standard Test Method for Shear Adhesion of Pressure-Sensitive Tape

Significato e uso 4.1 Procedure A measures the ability of the pressure-sensitive tape to adhere to a standard steel plate under constant stress. This may or may not involve the tape’s ability to adhere to other surfaces. 4.2 Procedures B, C and D may be used to determine the shear adhesion of tape commonly used to seal fiberboard boxes in packaging applications. 4.3 Procedure D measures the shear adhesion of pressure-sensitive tape to non-standard fiberboard, lining board, corrugated cardboard or other tested [...]

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14 novembre

ASTM D3759/D3759M-2019 “Standard Test Method for Breaking Strength and Elongation of Pressure Sensitive Tape”

Significato e uso 5.1 The information provided by this test method can be used for material specifications for product design and quality assurance applications. Can be used to compare different products. 5.2 The use of the test method must be related to the test purpose. One purpose is to determine the relative strength of the tape at the time of purchase or use. Another aim is to identify or characterize a specific backing material. 5.2.1 The test may be performed on the [...]

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14 novembre

ASTM D3815/D3815M-2019 Standard Practice for Accelerated Weathering of Pressure Sensitive Tape with Open Flame Carbon Arc Exposure Equipment

Significato e uso 4.1 This practice does not necessarily directly simulate natural weathering exposure. 4.2 The results of this practice shall not be represented as equivalent to the results of any natural weathering test until the satisfactory relevance of the relevant material has been established. 4.3 Results may vary when operating conditions vary within the acceptable range of the instruments specified in Practice G151 and G152. ASTM D3815/D3815M-2019 Standard Practice for Accelerated Weathering of Pressure Sensitive Tape with Open Flame Carbon Arc Exposure [...]

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13 novembre

Metodo di prova standard ASTM D4498-2015 per la temperatura di guasto termico nel taglio di adesivi hot melt

Significato e uso 4.1 Temperatura di guasto termico Viene impostata una temperatura limite alla quale l'adesivo non deve essere esposto durante l'uso sotto carichi di taglio. Fare un passo 1: Scopo 1.1 Lo scopo di questo metodo di prova è determinare la temperatura della stratificazione dei campioni incollati con adesivo hot melt sotto forze di taglio statiche. 1.2 I valori espressi in unità SI sono considerati standard. I valori indicati tra parentesi sono solo di riferimento. 1.3 Questo standard non è destinato ad affrontare tutti i problemi di sicurezza [...]

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13 novembre

Metodo di prova standard ASTM D4499-2015 per la stabilità termica degli adesivi hot melt

Significato e uso 5.1 Hot melt adhesives usually need to be used at higher temperatures to make the viscosity of the adhesive low enough that it can be easily handled in typical hot melt equipment. Adhesive changes caused by exposure to the harsh environment required for hot melt processing can disrupt the adhesive application process and may affect the quality of the adhesive bond. Changes in adhesive viscosity may affect the amount of adhesive dispensed by the sizing machine. Phase [...]

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13 novembre

ASTM D5105-2019 Standard Practice for Accelerated Outdoor Weathering of Pressure-Sensitive Tape Using Concentrated Natural Light

Significato e uso 4.1 This practice provides a way to qualitatively assess the impact of outdoor weathering on pressure-sensitive tapes. The resistance of the strip to outdoor weather is determined relative to the resistance of the control strip with known stability. 4.2 If the tests described in this practice produce the same type of degradation as in real time exposure to the same material, the results of these short-term tests may be used to determine the quantitative effects of natural weathering. 4.3 [...]

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