Fabric test procedures

There is a range of important characteristics required in order to ensure correct function of filtration media. There are the primary characteristics of the filtration media concerning the ability to remove particles classified by filter rating and also the fabric characteristics having a direct influence over the filter performance. Whilst the filtration media must remove a specified amount of debris, they must also be resistant to various contaminants and mechanical effects. 

The absolute rating refers to the size of the largest particle which will pass through the pore opening, which has a direct relationship to the actual pore size in the filter. This rating is, however, very subjective, as the performance can be altered by the pore and particle shape. Another important factor is the considerable difference that can be expected between the actual and rated performance due to the build-up of coutaminauL 

The microbial rating is generally used for membrane filters that are used in the sterilisation industry and is expressed as the ability of the filters to sterilise liquids. The filter permeability is the expression of resistance to flow provided by the filter media. This direct method establishes the permeability and can provide flow and pressure drop data with respect to fluid temperature and viscosity, filter size, and time. The effect of pulsating flow is the loosening of fine particles by agitating the filter. 

Since the main function of any filter is the removal and separation of impurities, and the filters are rated in many different ways, it is inevitable that many tests are available to substantiate these ratings. The tests include the bubble point test used to establish the mean filter rating and the multi-pass test which provides the beta ratio of the hydraulic and lubrication filters. 

The dirt capacity and pressure drop test are similar in the respect that they can use the same apparatus. The dirt capacity test can be used to determine the dirt holding capacity 

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Diverse appHcations for the fabric sometimes demand specialized tests such as for moisture vapor, Hquid transport barrier to fluids, coefficient of friction, seam strength, resistance to sunlight, oxidation and burning, and/or comparative aesthetic properties. Most properties can be deterrnined using standardized test procedures which have been pubHshed as nonwoven standards by INDA (9). A comparison of typical physical properties for selected spunbonded products is shown in Table 2. 

In medical apphcations, many test procedures have been developed for screening the efficiency of fabrics to block the passage of vimses, blood-home pathogens, etc. 

Overall, the test methods pubhshed by INDA (Table 4) continue to be the general tests used to characterize fabrics however, specific market apphcations often generate special test procedures to fiilfill unique needs. 

Other Equipment Cost ModiEers. Temperature, pressure, or corrosive conditions can act as modifiers of the base cost by requiring thicker vessel walls, more expensive alloys, special seals, more expensive fabrication, and special testing procedures. Separate materials and process severity factors for temperature, pressure,and material,, multiply the base (mild steel) cost as ... 

Torsion property As noted, the shear modulus is usually obtained by using pendulum and oscillatory rheometer techniques. The torsional pendulum (ASTM D 2236 Dynamic Mechanical Properties of Plastics by Means of a Torsional Pendulum Test Procedure) is a popular test, since it is applicable to virtually all plastics and uses a simple specimen readily fabricated by all commercial processes or easily cut from fabricated products. 

We have developed another bench for the measurement of the contrast value. Contrast measurement have been carried out on the MMA fabricated by Texas Instrument, in order to establish the test procedure (Zamkotsian et al., 2002a Zamkotsian et al., 2003). We can address several parameters in our experiment, as the size of the source, its location with respect to the micro-elements, the wavelength, and the input and output pupil size. In order to measure the contrast, the micro-mirrors are tilted between the ON position (towards the spectrograph) or the OFF position (towards a light trap). Contrast exceeding 400 has been measured for a 10° ON/OFF angle. Effects of object position on the micro-mirrors and contrast reduction when the exit pupil size is increasing have also been revealed. 

Consumer Safety Regulations are based on test procedures which are scientifically unsound and that they contradict the essentials of composites testing and hazard based fire tests, large scale hazard based tests involving the newer types of combustion modified PU foams with suitable fabrics have shown... 

Test procedures established by Committee RA-33 include a test ribbon intended to characterize the ozone content of air to which fabrics are exposed. The test ribbon is dyed to the tertiary gray shade with Cl Disperse Blue 27. Committee RA-33 has also established a test ribbon for nitrogen dioxide gas fading. 

Tensile Testing. Tensile tests were run on an Instron 1000 using a 5.08 cm (2 Inch) guage length and a speed of 12.7 cm (5 lnches)/mln. The procedures In Burlington Test Procedure FP-015 (ASTM-D-579) were followed. At least 5 specimens of each sample were tested. Fabric tests results are quoted for the warp direction only. The percent retention of tensile strength was calculated from the equation % retention where F and F(j are the... 

Initial Characterization. Modern silk was subjected to tensile testing to evaluate the test procedure to be used, the number of samples required and the expected precision. Five fabric samples tested in the warp direction were found to give a coefficient of variation of less than 5% for breaking-load and less than 10% for strain-to-break. 

To meet fabricated dimensional tolerances different approaches are used. They include use of specific fillers and reinforcements and process control (Chapter 3). Popular filler used is short glass fibers (Chapter 15). Over 50wt% of all types of glass fibers used with different plastics and by different processes are used in injection molding compounds. Table 2.2 shows the shrinkage of different unreinforced plastics ad glass fiber reinforced plastics based on ASTM testing procedures. 

Rice has suggested that in order to conserve historic colorants, it is necessary to know what constitutes the color, what chemicals affect it and how, and what factors cause it to fade or change (16), The specific objectives of this investigation were two-fold to discover dye types and characteristics in the voile fabric to discover if and how the fabric color changes in response to selected conditions it could have encountered in its wear life. This information could indicate possible factors to explain the types of discolorations on the dress. Experimental procedures and results for both objectives followed separate courses and therefore will be discussed separately. Results from the investigation of the first objective in part determined testing procedures for the second. 

Laboratory Treatments. Colorfastness of the dyed wool samples was determined in aqueous and nonaqueous media. Colored samples were cut into 2- X 2-in. squares and sandwiched between multifiber fabrics (Test Fabrics) and undyed wool fabrics of the same dimensions. The fabrics were loosely sewn together by hand with white cotton thread. Two surfactants were chosen for the aqueous treatments Tergitol NPX, a nonionic ethoxylated nonylphenol (Union Carbide) and Orvus WA, an anionic sodium alkyl sulfate (Proctor Gamble). Solutions of 0.1% surfactant in distilled water were prepared. Tests were run in 250-mL Erlenmeyer flasks at a liquor-to-cloth ratio of 50 1. The flasks were placed in an Eberbach constant-temperature shaker bath adjusted to 30 °C and an agitation of 40 cycles/min. Treatment time was 1 h, after which the samples were opened and allowed to dry on blotter paper. This same procedure was used for the nonaqueous treatments. Commercial grade tetrachloroethylene (R. R. Street Co.) with and without 1% Aerosol OT, the anionic surfactant sodium sulfosuccinate (Aldrich Chemical) was selected. The treated samples were removed from the liquids, opened, and dried on blotter paper in a ventilated hood. 

Usually, different methods are recommended for each particular type of material (film, fabric, carpet, rigid plastic foam, elastoplastics, etc.) to characterize its flammability adequately. Test procedures are divided into small-, medium-, large- and real-scale experiments, depending on the sample size. 

The aerospace industry has developed fabrication and testing procedures for resins that are radically different from those traditionally used with metals. However, little is known about the long-term durability of these relatively new nonmetallic composites, and their full potential has not been realized. By most standards, these materials are considered extremely stable, and if deleterious aging reactions occur, they are slow, requiring many years to cause component failure. 

Leather is a natural product and is subject to extensive variability. The physical and chemical properties vary considerably depending on the location from which the leather test sample is taken. The standard test method from the American Society for Testing and Materials (ASTM D2813, 1997) ensures random sampling of finished leather and fabricated leather items for physical and chemical tests. Test specimens should be cut from only one side of the backbone with their long dimension perpendicular to the backbone line. Test specimens should be taken from different parts of the shoulder, belly and tail of the leather. The number of specimens taken depends on the reliability of the test results, the deviation and the error of the testing procedures and should be recorded on the test report. Physical tests of leather and leather products, unless otherwise specified, should be performed under the standard atmospheric conditions of 50 4% relative humidity at 23 1 °C. 

Chemical finishing is an unportant area in textile processing and requires a diligent fabric testing program to maxunize the benefits of the chemical treatments. Many chemical finishes have an optimum level of application, too much chemical can be wasteful, too little can compromise the desired fabric properties. The development of the appropriate performance test methods is just as important to the commercial success of a chemical finish as the development of the finish itself. A test method is appropriate if it provides useful, reproducible results that correlate with actual real world performance. The best test methods utilize simple, inexpensive equipment with easy to follow procedures and yield precise, accurate data. 

Fiber damage reduction has been demonstrated in the laboratory, according to the yarn-to-yarn abrasion test carried out in the washing liquor. Details of the test procedure may be found in Azoz [66], Evidence of fabric protection by clay/PDT has also been collected in consumer tests. 

This book in no way condones illegal activity It is your responsibility to determine the legality of your actions. Further, because we have no control over the workmanship, materials, tools, methods, or testing procedures employed, we hereby disclaim any responsibility for consequences resulting from the fabrication or compounding of any item described in this book. Ne cannot and will not accept any responsibility for this information and its subsequent use. This book is sold for informational purposes only ... 

Note 3 of the author The first test cycle procedure (see below) is almost universally used for testing WPCs. Other cycle procedures (five of them are listed in the ASTM) are used mainly in automotive interior and exterior testing, and fabric testing. Only the first test cycle is described here as follows ... 

Safety testing procedures have been selected and the majority of the unique test fixturing has been fabricated. 

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