Laboratory Test Methods
REF: FTM 191A, Method 534 (Wyzenbeck) REF: Method 5306, CCC-T-191B (Tabor)
Wyzenbeck: Specimens held under required pressure and load are placed on an Oscillating Cylinder loaded with #0 emery paper (unless otherwise specified) and are run the required number of cycles.
Tabor: Samples of coated fabric are abraded on one or both surfaces with a Taber abrader. Various combinations of abrasion wheels and weights are used, as specified. Generally, the end point is reported in cycles to initial fabric exposure. However, some customers and military specifications call for running a given number of cycles and then examining the sample for appearance, or then recording the loss in weight. Some specifi¬cations call for the number of cycles at which initial tearing of yarns occur.
REF: Method 5950, CC-T-191B
Method 5970, CCC-T-191B
Method 8211-Federal Standard 601
The adhesion of coating to fabric or between plies of multi-ply fabric is determined by pulling or peeling them apart. The coat¬ing or bias plies, or knit fabrics, must be supported by cement¬ing to a non-stretchy material. The jaws must be wider than the specimen. Results may be expressed as pounds per inch of width or pounds per 2" of width.
REF: MIL-B-3018K, Sec. 4.5.8
This test determines the hydrostatic pressure resistance on waterproof material after being exposed to naptha. Specimens are covered by naptha for 15 minutes. Then air-dried for five minutes. Specimen is then taken to the Mullen Hydrostatic tester to determine amount of pressure to force water through exposed fabric. Reported in psi.
REF: Fed. Standard 191A Method 5972
This method is intended for determining the adhesion of coating on coated cloth by measuring loss in resistance to water penetration after the coated cloth has been stretched. Specimen is placed on an Instrom and stretched to a load of 30 lbs., and retained for 30 seconds. The specimen is then removed and taken to the Mullen Hydrostatic Tester to determine amount of pressure to force water through stretched fabric.
REF: Method 5850, CCC-T-191B
ASTM D 573-67 (Re-approved 1972)
Method 7221-Federal Standard 601
Samples of either coated fabric or rubber slabs are placed in thermostatically controlled, circulating air ovens and are aged at 158ûF for 72 hours. Then, properties, such as tensile, are determined and compared with the original properties. Various other temperatures and lengths of exposure may be specified.
REF: MIL-C-19002 D, Sec. 4.6.7
Coated fabrics, which are to be fabricated into air-holding arti¬cles, are tested by this method to ensure that the coated fabric does not allow air leakage. Fabric is inflated with specific lbs. of air, depending on customer’s specifications, covered with water, left for a determined amount of time, and checked for air bubbles.
REF: GM M-1812 11.B.4
Inland T-469, IV.H
TRW, ES0006
10 - 2" x 2" squares are placed coating-to-coating, stacked five high, on aluminum plates in a 212ûF (100ûC) oven with a 20 lb. weight on top for seven days. They are then removed and checked for time to separate each specimen with a 50 gram weight attached to one corner. Reported in seconds to separate.
REF: Method 5910, CCC-T-191B
A specimen 1" x 6" is supported at a 30û angle in a grill-like holder, protruding 1/2" below the holder. The exposed edge is bent down and ignited by exposure to a match flame for five
REF: Method 5122, CCC-%-191B
ASTM D 751-73
A sample is clamped across the orifice in a power-driven Mullen tester with a rubber diaphragm. The pressure at which rupture occurs is recorded as the Mullen Burst, gross value.
No Reference
The ease with which an un-buffed coated fabric can be cement¬ed to itself is determined by washing two 2" x 12" samples with a suitable solvent and cementing them together with a suitable cement. After drying and curing, the two pieces are pulled apart at 12"/minute. The results are expressed in lbs. per inch of width. In order to obtain reproducibility at different labora¬tories, the solvent cement and exact preparation technique must be carefully described.
REF: ASTM D 4032-94
This test gives a force value related to the stiffness of a product. A 4" x 8" specimen is folded to make a 4" x 4". This is placed on the bend tester (J. A. King Circular Bend tester with Chatillon Digital Force gauge). The force gauge is pushed through the specimen ant the force to do so is read. Measured in lbs., n, or k (pounds, newtons, kilonewtons).
REF: ISO 5081
This method determines the comb stripping resistance. Used to simulate the strength of a sewn seam. A 50 mm x 200 mm specimen is placed on the Instrom, in a special fixture set100 mm apart. Ten mm of fabric is placed in top fixture and pierced with 12 one-mm pins. Force is recorded with the amount of pressure to pull through pins. Reported in kn (kilonewtons).
REF: ASTM D 395-69
Method 3311-Federal Standard 601
A cylindrical disc 1/2" in thickness and 1-1/8" in diameter is subjected to compressive stress in a suitable loading device. The sample is held under either constant load (Method A) or constant deflection (Method B) for a specified length of time and at a specified temperature. The residual decrease in thick¬ness, expressed as a percentage of the original thickness (Method A) and a percentage of the deflection under load (Method B), is reported as the Compression Set. Care must be used to report any values as Method A or Method B.
No Reference
This equipment is capable of conditioning samples over a wide range of temperatures and humidities to obtain the effect on properties before and after exposure. One of the most fre¬quently used conditions is 158ûF and 95% Relative Humidity for two weeks.
No Reference
Discs of the coated fabric 1-1/8" in diameter and 2-1/4" in diameter are allowed to condition 24 hours at 70ûF with the curling side facing up. The distance from the table top to the highest point of the curl is measured and reported as the curl.
REF: ASTM D 430
This procedure estimates the ability of compounds or coated fabric to resist dynamic fatigue. This test is designed to simulate the continually repeated distortions received in service by many rubber or thermoplastic articles. These distortions may be pro¬duced by extension, compressive and bending forces, or combi¬nations of them. Reported number of cycles to failure.
REF: ASTM D 471 Sec. 15 (Effects of Liquids)
Cured specimen Durometer is measured and recorded. The specimen is placed in Toluene for 24 hrs. Specimen is removed and Durometer is re-measured. Before and after readings are calculated to give loss in hardness.
REF: Coated Fabric-Method 5102, CCC-T-191B
ASTM D 751-73
Rubber
ASTM D 412-68
Method 4121, Federal Standard 601
A sample of rubber or of coated fabric is subjected to a tensile stress on the Tensometer. The elongation or, more properly, the ultimate elongation is the extension between benchmarks at the moment of rupture. The ultimate elongation is expressed as a percentage of the original distance between the benchmarks.
REF: Method 5903-T, CCC-T-191B
There are several different tests for flame resistance. The Vertical Flame Test (Method 5903T), which is the most severe, is run as follows: A sample is held in a vertical position in a metal frame, while a 1-1/2" flame is applied at the lower end of the sample for a period of 12 seconds. Three values may be reported. The flame time is the length of time, in seconds, for which the flame continues after the removal of the burner. The glow time is the length of time for which the sample glows after the flame has died out. The char length is the distance the charred sample will tear when subjected to a specified load. Also see “Burning Rate - 30û Angle”
REF: Clark-Method 5204, CCC-T-191B
Tinius Olsen-Method 5202, CCC-T-191B
In the Clark Test, a 11/4" wide strip is placed between two1" diameter rollers held together by a spring pressure, one of which is slowly rotated. The overhanging end is adjusted until, when the framework is rotated clockwise and counter clock¬wise through 90û, the specimen just falls over in both direc¬tions of rotation. The length of the overhanging portion is then reported in millimeters. Testing is done at 70û and -40û.
In the Tinius-Olsen test, one end of a 1" x 3" sample is placed in a clamp, which will rotate the sample up to 90û. The other end of the sample then pushes against a balanced arm and rotates it. The arm gives readings up to 100 units. The stiffer the sample, the higher the reading. The balance arm has several weights, which are added for stiffer samples. We record the weight used on the arm and the readings at 10û, 20û, and 30û, but usually report only the weight used and the value obtained at 30û.
REF: ISO 5981
This test measures the durability of coated fabric to combined sheer flexing and rubber on itself. Reported in number of scrubs to failure.
ASTM D 2097-69
Determines the single and double bending from a flat position type, flexing is necessary to produce cracks or wear through or loss of adhesion on materials, such as gas diaphragms, luggage, upholstery, shoes, and other coated fabrics.
Flat samples are mounted in a cylindrical manner on a recipro¬cating piston action Newark Flexer and flexed at a rapid rate (480 cycles/minute) until the desired end point is reached.
No reference
Determines the vertical running bend type flex life of coated fabrics used for gas diaphragms, luggage, upholstery, shoes, etc. The samples are flexed in a manner simulating wear conditions until a specified state of deterioration occurs, such as cracks and/or breakthrough.
REF: MIL-T-6396 C (ASG)
• determine the diffusion rate of fuel through a sample of fuel tank liner material. A volatile fuel mixture (Iso Octane 70%, Toluene 30%) is sealed in a cup and inverted against the tank liner. Periodic weighings are made for eight days and the loss calculated in fluid ounces per square feet per day over the last three-day period.
REF: ASTM D 2240-75
Method 3021-Federal Standard 601
Durometer hardness is determined with a Shore durometer or equivalent, which measures the resistance to penetration of its indenter point. The indenter point extends 0.1" beyond the surface of the presser foot. The durometer reads zero when the indenter is fully extended and reads 100 when the durometer is pressed to a flat piece of plate glass. The sample should be at least 1/4" thick. The harder the rubber surface, the more the indenter is pressed back into the instrument.
REF: MYSS 302
To determine the burn resistance for materials used in certain components of the occupant compartment of motor vehicles.
The sample 4" x 14" long is mounted horizontally and placed on a stand in a cabinet, which has a burner mounted on the door, such that, when closed, the flame impinges on the edge of the material. The burning rate is obtained after the flame front reaches a gauge mark 11/2 inches from the ignited end. Samples are rated DNI, SE, SE/NBR, SE/B, or B, depending on the extent of burning.
REF: Mullen-ASTM D 751-73
Method 10511-Federal Standard 601 Suter-Method 5514, CCC-T-191B
ASTM D 751-73
A. Samples are clamped in a motor-driven Mullen tester with water in the cylinder and without a diaphragm across the open¬ing. The pressure is raised at a steady rate. The pressure at which the first drop of water comes through the sample is recorded with an “L” following the value. If the material goes to rupture, the reading at rupture is recorded with a “B” fol¬lowing the value.
B. When low-pressure accuracy is required, the Suter or Rising Column of Water method is used. The maximum range on this method is equivalent to about 2 psi. This method takes much more time than the Mullen method.
REF: ISO/DIS 13937-2
This method evaluates the tear resistance of coated materials. 8" x 8" specimen with a 4" slit in the middle is placed on the Instrom. Clamps are set 100 mm apart. Specimen is pulled in both direc¬tions to obtain the tear strength of the coated fabric. Measured in both warp and fill directions. Reported in kn (kilonewtons).
REF: Method 5874-CCC-T-191B
1/8" Bar as in MIL-C-20696
We have a thermostatically controlled low-temperature box, which can be accurately maintained at temperatures as low as - 80ûF. Both coated fabrics and rubber strips can be tested by three methods:
A. Cracking a 180û-bent loop with a falling weight.
B. Cracking a 180û-fold with a hand roller of specified weight.
C. Cracking by bending 180û over a 1/8" bar at the specified temperature.
REF: ASTM D 412-68
Method 4131 - Federal Standard 601
The modulus of a rubber compound may be measured (on the Tensometer) on the same dumbbell-shaped piece of rubber that is used for the determination of tensile strength. The modu¬lus is the stress in pounds per square inch at any given extension. The higher the value, the less the ease of extension. Usually the 300% modulus is reported.
REF: MIL-C-20696F, sec. 4.4.7
A sample of fabric is placed into a frame, which forms a basin of fabric. Lubricating oil is poured into the basin to a depth of 1/2". After one hour of exposure, the bottom of the fabric is observed for any seepage or permeation of oil.
REF: Method 5460, CCC-T-191B
ASTM D 815-73
Samples of coated fabric are tested in a Cambridge Permeameter using hydrogen gas. The tests are conducted for a two-minute interval and the instrument then gives the value in liters per square meter per 24 hours. Results can be converted to the equivalent values for helium or carbon dioxide by using factors recommended by the bureau of Standards. The higher the value, the greater the rate of diffusion of the gas through the coated fabric.
REF: ASTM D 814-55
(Re-approved 1970)
A specified amount of the test liquid is placed in a cup or jar of specified dimensions, over which the sample is placed and sealed. A period is allowed for the attainment of equilibrium; after which, the cup or jar is weighed accurately then inverted. After the specified length of time, the cup or jar is reverted to the upright position and again weighed accurately. The weight loss is calculated and generally expressed as fluid ounces per square foot per 24 hours.
REF: Method 2811, CCC-T-191B
ASTM. E70-68
A 100-gram portion of the fabric or coated fabric is cut up into small pieces, placed in distilled water for a period of three hours, and stirred at intervals. The solution is divided into two portions with some of the fabric in each. The PH is then measured with a BeckmanPH Meter. The lower the value, the more acidic; the higher, the more basic. A value of seven represents neutrality.
REF: MIL-T-6396 C (ASG)
To determine the force necessary to pierce or puncture coated fabric, especially those used for fuel tank liners. A sample is mounted to a small cup or device, which will hold it taut; and a screwdriver-tipped device is brought into contact and pushed through the sample. The force in pounds required to penetrate is measured.
REF: ASTM D751-98 Sec. 22
The test allows us to measure the Puncture Resistance of fab¬rics. Specimens are placed in special fixtures and the force, which is required to puncture the specimen, is recorded. Reported in pounds or kilonewtons.
REF: ISO 5081
This method provides for the determination of the breaking strength and elongation at break of specimens. 50 mm x 300 mm specimen is placed on the Instrom with the clamps set 200 mm apart. Specimens are pulled until broken. Strength elongation is recorded in both warp and fill directions. Reported in kn (kilonewtons).
REF: ASTM D 1054-66 (Re-approved 1972)
We measure resilience on the Bashore Resiliometer. A bob is allowed to fall vertically to the rubber sample at the base of the instrument. The distance to which it recovers after impact is reported as a percentage of the original standard weight. ASTM D 1054-66 is similar, but not identical.
REF: R. T. Vanderbilt Handbook 1948 p. 433
In this test, a 2" x 4" sample is used. There are two 2" x 1" jaws 7/16" apart, which move back and forth in opposite direc¬tions for a distance of 11/2" and at 110 cycles per minute. The sample is clamped in the jaws so that a 2" loop is formed between the jaws. A 29 oz. weighted rider is lowered onto the loop. When the machine is started, a vigorous scrubbing action of the coated fabric against itself occurs. The number of cycles to failure, represented by peeling of the coating or wearing through to the fabric, is recorded. Some specifications call for visual examination after a specified number of cycles. Values are usually determined for each side of the coated fabric, and for warp and filling directions.
REF: Reeves Method SOP 129
A 15" x 15" specimen is marked to 250 mm x 250 mm square, measured in three places inside the square in both warp and fill directions. Samples are then placed in a circulating air oven for a required time and at a required temperature. Specimens are then removed and reconditioned for 30 minutes and re-meas¬ured. The dimensional change is reported to the nearest 0.1%.
No reference
ASTM Method Pending
To measure the smoke-generating characteristics of solid mate¬rials (of given thickness and shape), when mounted and tested as described, by the attenuation of a light beam by suspended particulate matter generated from materials under both pyrolitic decomposition (smoldering) and flaming combustion within a closed chamber.
REF: GM T-469, Sec. M
Specimens are measured under 271 lbs. pressure after 10 min¬utes, reported in stretch percent, then removed, laid on a flat sur¬face for 10 minutes, and measured again to report set percent.
REF: ASTM D-257-92
AATCC 76-1989
Keithly Model 487 and 8008 User’s Manual
Surface Resistivity: The electrical resistance of the surface of an insulator material.
Volume Resistivity: The electrical resistance through one-centime¬ter cube of insulating material, if expressed in ohm - centimeters.
REF: ASTM D 471-71
Method 6211, Federal Standard 601
The swelling of rubber or rubber-coated fabrics in various liq¬uids is measured. Our standard test is to determine the percent increase in volume after 24-hour immersion in Toluol at room temperature. The volume of the sample is measured by dis¬placement. The sample is then immersed for 24 hours, and the volume is measured again. Special immersion fluids, such as ASTM fuels and oils, are used wherecalled for. Also, in some cases, immersion swells are run at elevated temperatures. In some cases, the percent gauge or weight increase is determined rather than the volume increase. Sometimes long narrow strips are immersed and the percent increase in length noted.
REF: ASTM D 751-66 (Tongue & Pendulum)
Method 5132, CCC-T-191B (Pendulum)
Method 5134, CCC-T-191B (Tongue)
Method 5136, CCC-T-191B (Trapezoid)
A. Pendulum Method (Elmendorf): In this method, a 2.5" x 4" sample is held between two clamps at the base of the instru¬ment. The sample is then given a small exact nick by a knife attachment. The sample is then torn by releasing a pendulum, which falls through the force of gravity. The pendulum carries a circumferential scale to indicate the force required to tear the specimen. Scale readings are multiplied by appropriate factors to give the results in pounds or grams. Values are determined for warp and filling direct.
B. Tongue Method (Strip): A cut is made at the center of one 4" edge of a 4" x 6" sample. One side (2") is clamped in the lower jaw and the other side is clamped in the upper jaw of an Instrom. The jaws are separated at a speed of 12" per minute. The average of the five high points in the chart is reported as the tear strength in pounds. Values are determined for warp and filling directions.
C. Trapezoid Method: A trapezoidal sample 4" long on one edge and 1" long on the opposite parallel edge is used. A small nick is made at the center of the 1" edge. The non-parallel edges are clamped in the jaws of the Instrom. The tear pro¬gresses across the width of the sample. Values are reported in the same way as in the Tongue method.
REF: ASTM D 751-73
Method 5100, CCC-T-191B (Grab) Method 5102, CCC-T-191B (Cut Strip) Method 5104, CCC-T-191B (Ravel Strip)
Any one of the three methods may be specified for a fabric or coated fabric.
In the Grab method, 4" x 6" samples are cut in the warp and filling directions. An Instrom with 1" x 1" jaws is used. The jaws are 3" apart at the start and are separated at 12" per minute. To obtain accurate results, extreme care must be used to obtain proper alignment of the yarns in the jaws. Values are reported in pounds per inch.
In the Cut Strip method, 1" x 6" strips are cut in the warp and filling directions, carefully aligning the die with the yarns. Samples are then ruptured in the Instrom, and values are reported in pounds per inch.
In the Ravel Strip method, 6" long strips are raveled to exactly 1" width. Strips from the warp and filling directions are pre¬pared. Instrom values are then reported in pounds per inch.
REF: Method 5030, CCC-T-191B
ASTM D 751-73
Method 2011, Federal Standard 601
A federal gauge with .001" graduations is usually used to meas¬ure the thickness of the coated fabric or rubber. This gauge uses a dead weight rather than a spring.
REF: ASTM E 96-66 (Re-approved 1972)
To determine the rate of water vapor transmission through coated fabrics. A sample is sealed on top of a small aluminum cup containing a small amount of water, and air is blown across the top. The coated side is next to the water. The cup is weighed before and after 24 hours, and the rate of water vapor loss through the coated fabric is found and reported as grams per hour per square meter.
REF: Method 5804, CCC-T-191B
ASTM G-23 (Carbon Arc)
ASTM G-26 (Xenon Arc)
Samples are exposed in the Weatherometer of specified design and under specific conditions. The weatherometer simulates rain and sunshine by the use of water spray and carbon arcs. Physical tests and visual examination indicate the deterioration that has occurred at the end of a particular period of exposure. Military specifications frequently outline minimum physical test requirements, which are to be met after a specified period of exposure. Comparative results are an indication of comparative outdoor weather ability.
REF: Method 5041, CCC-T-191B
ASTM D 751-73
The weight is determined by cutting four discs evenly spaced across the width of the roll and no closer than 2" to a selvage edge. The diameter of the disc is such that the weight of four of them in grams is equivalent to ounces per square yard. The discs are conditioned and weighed on an analytical balance. Some specifications permit a calculated weight determined by obtaining the length, width, and weight of a full roll, and then calculating the weight in ounces per square yard.
No Reference
A hole is cut in the center of a 10" diameter sample of the coated fabric. Boltholes are cut around the outer edge of the sample, which is then bolted into the wicking tester. The bolts are tightened with a torque wrench, and the unit immersed in water. Air pressure is then built up in the cavity in the center of the unit. The hole in the center of the fabric gives the com¬pressed air access to the fabric insert. Observations are made to determine the lowest pressure at which air bubbles emerge from the fabric edge, which protrudes from the instrument. The pressure is generally raised in 10 psi increments until leak¬age occurs; the maximum test pressure is 100 psi. The pressure at which initial leakage occurs is recorded, and the material is reported as being anti-wicking to the next lowest pressure.
REF: ASTM D-3775-85
ISO 7211/2
Fabric yarns are counted using either a pick counting glass or an RMS Optical Grating Thread Counter. Fabric is counted five times and averaged to the nearest 1/2 yarn. Both warp (ends) and fill (picks) are counted.