GB/T 4146.3-2011Textiles - Man-made fibers - Part 3: Terms of inspection (English PDF)

2.1 Terms of inspection for general man-made fibers

2.1.1 Standard atmosphere

An environment where the relative humidity and temperature are controlled, and textiles are conditioned and tested under this environmental temperature and humidity.

2.1.2 Relative humidity

Under the same temperature and pressure conditions, the ratio of the actual pressure of water vapor in the atmosphere to the pressure of saturated water vapor, which is expressed as a percentage.

2.1.3 Preconditioning

A treatment in which the sample or specimen is conditioned to a rate lower than the rate of moisture regain before conditioning in the test standard atmosphere.

2.1.4 Conditioning

A treatment in which the sample or specimen is placed in the test standard atmosphere for a certain period of time to reach moisture absorption equilibrium.

2.1.5 Moisture equilibrium

The state, in which the moisture absorption and moisture release of textile fiber reach a balance, and the change of its quality tends to zero.

2.2 Terms of inspection for sampling of man-made fibers

2.2.6 Laboratory sample

The product unit or part of the fiber taken from the lot sample according to the provisions that are used as the source of the test sample.

2.2.7 Test specimen

The part that is taken from the laboratory sample for testing.

2.3 Terms of inspection for linear density of man-made fibers

2.3.1 Linear density

Mass per unit length of fiber or yarn.

2.3.2 Nominal linear density

The linear density that is mentioned in the sales documents (contract, invoice, etc.).

2.3.3 Percentage of linear density deviation

The percentage of the difference between the actually-measured linear density and the nominal linear density of chemical fiber to the nominal linear density.

2.3.4 Tex

A unit that expresses linear density, which is the mass grams per kilometer of fiber. The commonly-used unit is tex or dtex, 1tex=10dtex.

2.3.5 Number of monofilaments

The number of monofilaments that is included in a multifilament formed by a porous spinneret.

2.3.6 Ratio of monofilament deviation

The percentage of the difference between the number of spinneret holes forming a multifilament and the actually-measured number of single filaments to the number of spinneret holes.

2.4 Terms of inspection for the length of man-made fibers

2.4.1 Nominal staple length

The fiber length that is mentioned in the sales documents (contract, invoice, etc.).

2.4.2 Percentage of length deviation

2.5 Terms of inspection for the tensile properties of man-made fibers

2.5.5 Knot breaking force

The tensile breaking strength of a fiber or yarn with a knot of a predetermined shape, and that is clamped between the two clamps of the tensile tester.

2.5.6 Loop breaking force

The tensile breaking strength of two fibers or yarns that are clamped between the two clamps of the tensile tester, and that are taken from the same yarn package and hooked together in a prescribed manner.

2.5.7 Single fiber breaking force

The maximum force that is measured when a single fiber sample is stretched to break, which is generally expressed in centinewtons (cN).

2.5.8 Single strand breaking force

The maximum force that is measured when a single yarn (multifilament) sample is stretched to break, which is generally expressed in centinewtons (cN).

2.5.9 Breaking point

On the force-elongation curve or stress-strain curve, the point that is corresponding to the breaking force or breaking stress.

2.5.10 Yield point

The turning point from the initial straight part to the bent part on the force-elongation curve or stress-strain curve, that is the point where the fiber begins to undergo permanent deformation.

2.5.11 Time to break

The time, that the tensile test is carried out under specified conditions, is required from the time the specimen is stressed to the maximum force.

2.5.12 Tenacity

The strength of the unit linear density or unit section (before stretching) of the specimen, which is expressed in Newtons per tex (N/tex) and centinewtons per tex (cN/dtex).

2.5.13 Tenacity at specified elongation

The corresponding strength when the specimen is stretched to the specified elongation.

2.5.14 Breaking tenacity

2.5.25 Stress-strain curve

A graph that characterizes the relationship between stress and strain of a fiber under pressure, shear, tensile or torsion force.

2.5.26 Force-extension curve; tensile curve; load elongation curve

The graph that characterizes the relationship between force and elongation of the fiber under tensile force (load).

2.5.27 Constant rate of extension (CRE) dynamometer

The tester that stretches the specimen at a constant speed.

2.5.28 Modulus

The parameters that is used to characterize fiber deformation characteristics. On the stress-strain curve, the ratio of stress increment to strain increment.

2.5.29 Initial modulus

The slope of the initial straight line on the stress-strain curve of fiber.

2.5.30 Young's modulus

On the stress-strain curve of elastic fiber, the ratio of stress increment to strain increment in the elastic region of the fiber.

2.5.31 Chord modulus

The ratio of the stress difference to the strain difference between two points specified on the stress-strain curve of the fiber.

2.5.32 Elastic modulus; modulus of elasticity

The ratio of stress to strain of an elastic medium within the proportional limit.

2.5.33 Secant modulus

The special case of chord modulus, it is the ratio of the stress difference to the strain difference between the zero point and any point on the stress-strain curve.

2.5.34 Tangent modulus

2.6 Terms of inspection for the crimp/crimp contraction properties of man-made fibers

2.6.8 Crimp modulus

After the textured yarn undergoes crimp development, the ratio of the difference between the straightened length measured under the specified load and the elastic length in the elastic range to the straightened length.

2.6.9 Crimp development

The potential crimp is re-developed.

2.6.10 Crimp development medium

The substances that can make the tested textured yarn form temporary crimp and permanent deformation, such as dry hot air, water vapor, hot water, etc.

2.6.11 Crimp elasticity

The performance that the fiber is straightened by applying external force, and after the external force is removed, the crimp can obtain the recovery.

2.6.12 Percentage of crimp elasticity elongation

An index that indicates the degree of elasticity and crimping of textured yarn (filament).

It is the percentage of the difference between the length of the textured yarn (filament) under the heavy load and the initial length under the light load to the initial length.

2.6.13 Percentage of crimp elastic recovery

An index that indicates the elasticity and crimp stability of textured yarn (filament). It is the percentage OF the difference between the length of the textured yarn (filament) under heavier load and the recovery length under light load after removing the heavy load and the difference between the length under heavier load and the initial length TO the initial length.

2.7 Terms of inspection for heat shrinkage of man-made fibers

2.7.1 Shrinkage

The percentage of the difference between the length of the fiber or filament yarn before and after treatment according to the specified conditions to the length before treatment.

2.7.2 Heat shrinkage

The percentage of the difference between the length of the fiber or filament yarn before and after heat treatment (such as dry heat treatment, boiling water treatment, steaming treatment, etc.) to the length before treatment.

2.7.3 Shrinkage in hot air

2.8 Terms of inspection for filament twist level of man-made fibers

2.8.8 Twist liveliness

The tendency of twisting the textured filament yarn to return to its shape before twisting.

2.8.9 Residual torsion

The torsional stress remains in the textured filament yarn. When one end of the yarn is fixed and the other end is free, it is expressed by the number of revolutions per unit length.

2.8.10 Residual twist

The twist remains on the strand silk after heat setting.

2.9 Terms of inspection for filament degree of intertwining for man-made fibers

2.9.1 Degree of intertwining

The number of intertwining points in the unit length of the strand silk, which is expressed in (pieces/m) per meter.

2.9.2 Interlacing distance

The distance between two adjacent interweaving points.

2.9.3 Intertwining stability

The index that is used to measure of the stability (fastness) of the intertwining points.

2.9.4 Extrication force

The setting minimum load value that can meet the requirements of network stability when measuring the degree of intertwining, which is expressed in centinewtons (cN).

2.10 Terms of inspection for elastic fibers of man-made fibers

2.10.1 Tensile recovery circulation

A repeated process, in the tensile test of elastic fibers, that the specimen is stretched to the selected length at the specified initial length and tensile speed without interruption, and after cyclic elongation, it returns to the initial length.

2.10.2 Elasticity

The performance of the fiber, after the force that causes the fiber to deform is removed, that tends to immediately return to its original size and state of the fiber.

2.11 Terns of inspection for mass difference

2.11.6 Commercial allowance

In order to calculate the commercial mass, etc., the agreed value of the amount of moisture and the amount of extract to be added to the dry mass of textile fibers. It is expressed by the percentage of the extraction amount to the dry mass of the extracted fiber and the mass percentage of the dry fiber.

2.11.7 Gross mass

The total mass of the lot, or part of the lot, including the mass of the fiber and tare mass.

2.11.8 Tare

The sum of the quality of all the bedding, packaging, strapping, spool, bobbin, etc. related to the lot and packaging.

2.11.9 Net mass

The difference between gross mass and corresponding tare mass.

2.11.10 Conventional mass

The mass of the fiber at a given moisture regain.

2.11.11 Commercial mass

The mass of the fiber under the commercial moisture regain or the mass of fiber with dry mass of the fiber after extraction plus the mass of the corresponding commercial allowance.

2.12 Terms of inspection for appearance

2.12.1 Lousiness

The broken filament ends of the monofilament that protrudes from the surface of the multifilament, or the hairy phenomenon of the multifilament that is scratched.

2.12.2 Lousiness lump

The single or multiple filaments that protrude on the surface of the multifilament are broken and twisted into clumps.

2.12.3 Pearl string

A monofilament with continuous minute particles in a multifilament.

2.12.15 Brittle rupture filament

Brittle and breakable filaments that are formed by improper production process.

2.12.16 Tail filament

The filament head with the bottom of the filament tube wounding around one end of the bobbin.

2.12.17 Milky filament

The strand silk that appears the semi-finished filament in lustrous silk or matt strand silk.

2.12.18 White spatted filament

The strand silk that appears the white dots.

2.12.19 White knopped filament

The strand silk that appears in segments.

2.12.20 White specked filament

The filament with white misty spots on the surface.

2.12.21 Stained filament

Fiber that is stained with oil stains such as in yellow or black, etc. colors.

2.12.22 Leap filament

On the end face of the filament tube, the strand silk is deviated from the normal winding track and turns into a chord from an arc.

2.12.23 Joint

The connection after the strand silk breaks.

2.12.24 Stain

Oily filament, rusty filament and stains that cannot be washed by water.

2.13 Terms of inspection for defect

2.13.1 Defect

2.14 Other terms of inspection for fibers

2.14.1 Compression elasticity

The performance of fiber, after the textile fiber is subjected to pressure, its volume is reduced, and after the pressure is released, it can return to its original state to a certain degree.

2.14.2 Degree of bulkiness

An index that indicates the bulkiness of textured [bulked] yarn (filament). It is generally expressed by the volume of the textured yarn (filament) per unit mass under a certain pressure. Its unit is cubic centimeter per gram (cm3/g).

2.14.3 Degree of hollowness

An index that indicates the degree of hollowness of the hollow fiber. It is generally expressed by the ratio of the hollow part of the fiber cross-sectional area to the cross-sectional area.

2.14.4 Hole number

The number of cavities on the fiber cross-sectional area.

2.14.5 Degree of profile

An index that indicates the degree to which the abnormal fiber conforms to the abnormal specifications, which is expressed by the degree of difference between the fiber cross-sectional shape and the round shape.

2.14.6 Degree of acetalization

When polyvinyl alcohol fiber undergoes acetalization treatment, the percentage of the number of hydroxyl groups that are combined with aldehyde accounts for the total number of hydroxyl groups.

2.14.7 Monomer content

The percentage of the remaining unpolymerized monomers and oligomers in the synthetic fiber to the drying mass of the fiber.

2.14.8 Unevenness

The degree of unevenness in the thickness of the filament along the length direction.

2.14.9 Water retention

2.14.18 Residual sulfur content

The mass of residual sulfur in viscose fiber. It is expressed by milligrams of sulfur mass that is converted by the sulfur or sulfide remains in the 100g of absolutely dry fiber.

2.14.19 Sodium thiocyanate content

In orlon that is made by sodium thiocyanate method, the percentage of the mass of residual sodium thiocyanate accounts for the drying mass of the fiber.

2.14.20 Pulp content

The percentage of the mass of the oil agent and pulp in the textile fiber that is measured by the prescribed method accounts for the drying mass of the fiber.

2.15 Terms of inspection for raw materials of man-made fibers

3.1 Individual value

The result of any one observation (breaking strength, linear density, etc.) in a series of tests is called an individual value. The identification of individual value for the ith observation in a series of n observations is taken as xi.

3.2 Arithmetic mean

The sum of n individual values is divided by the number of individual values, n.

3.3 Variance

The sum of the squares of the difference between each individual value and the arithmetic mean in the n individual values, which is divided by (n-1). […]

3.4 Standard deviation