Textile testing slide share 1
- 1. Ms.S.Priya Asst Prof Bon Secours College for Women Thanjavur
- 2. Sample Preparation 1. When cutting specimens, avoid wrinkles, folds or creases. 2. Avoid getting oil, water, grease, etc. on the specimens when handling. 3. Using the smallest cutting die, cut six circular specimens from the fabric to be tested with each specimen being 1.5 inches (38mm) in diameter. Take care not to apply too much pressure on the cutting die as it will break the razor blades. 4. Weigh one specimen to determine pre-test mass. 5. Also use this measurement to determine mass/unit area. Preparation of Test Apparatus (see manual) 1. Make all tests in the standard atmosphere for testing. 2. Remove the specimen holders from the Martindale tester 3. Note that all three parts of the specimen holders (handle, face, and ring) are numbered1-6 and correspond to numbers on top of the Martindale tester. 4. Assemble the holder by: 5. Place the assembled holders into the machine, replacing silver caps and black knobs. 6. Add the required weight (9kpa for apparel, 12kPa for upholstery) by resting the weights on the ends of the handles. (kPa = 1 kilo Pascal = # pounds) Note that the weights are also numbered 1-6. 7. Set the counter system to record the desired movements using the third black button from the right.
- 3. The test method covers the measurement of the air permeability--the rate of air flow passing perpendicularly through a known area under a prescribed air pressure. Air permeability is an important factor in the performance of such textile materials as gas filter, fabrics for air bags, clothing, mosquito netting, parachutes, sails, tentage, and vaccum cleaners. It can also be used to provide an indication of the breathability of weather-resistant and rainproof fabrics.
- 4. How the Test Works: A circle of fabric is clamped into the tester and through the use of a vaccum, the air pressure is made different on one side of the fabric. Airflow will occur from the side with higher air pressure, through the fabric, to the side with the lower air pressure. From this rate of air flow, the air permability of the fabric is determined in mm/sec.
- 5. A lea strength tester measures the strength of one lea yarn. One lea means 120 yards. Strength is a measure of the steady force necessary to break a material and is measured in pound. The m/c works in constant rate of extension. Assuming the specimen to be extensible and an absence of any dynamic effects.
- 6. Working procedure At first one lea cotton yarn is measured by wrap reel and in this way 20 samples are taken for testing. Now, the first sample is fixed with the upper jaw and the lower jaw. The m/c is started and observed the dial until the sample is torn out. When the sample is torn out the m/c is stopped and the reading is taken. By this way the others’ reading are taken. Then all the samples are weighted and counts are calculated. C.S.P or C.L.S.P of the all samples are calculated. At last average and CV% are calculated
- 7. Thank you