Development
In the Spring and Autumn Period and Warring States Period, China not only used human senses to evaluate the quality of silk fabrics, but also used five-color pheasant feathers as the color standard for evaluating fabric dyeing. Starting from the Zhou Dynasty, the length and width of fabrics were measured with a ruler, and public standards were drawn up. With the development of textile technology, special instruments are required to inspect products to ensure stable product quality. Since the 20th century, textile enterprises have used manual and mechanical instruments to test semi-finished products and finished products. On the one hand, they check the quality, and on the other hand, they have become a tool to control the normalization and standardization of textile production. After the emergence of chemical fibers, more test items and instruments are required to reflect the quality and characteristics of the products. With the rapid development of modern electronic technology and computer technology, some modern textile instruments adopt direct digital display, and some are equipped with a micro-processing calculation system to directly print out the average number and dispersion index of test results, which improves the test efficiency and reduces Human error. There are many types of textile testing equipment, including mechanical property testing equipment, appearance quality testing equipment, fabric style testing equipment, physical property testing equipment, and process property testing equipment.
Mechanical property testing instrument
Test various properties of textile materials under mechanical external force, including tensile property testing instrument and wear resistance testing instrument.
Tensile property testing instrument
There are three types: ①Constant elongation type (CRE): The deformation rate per unit time of the sample is kept constant during the tensile process;
②Constant load type (CRL): The load increase rate of the sample is basically kept constant when the sample is stretched;
③Constant traction type (CRT): The sample is subjected to a clamp When pulling, the upper clamp has an irregular displacement according to the stress-strain characteristics of the material. The constant velocity traction type instrument appeared early and widely used, belonging to the mechanical type, often called the pendulum powerful machine.
Using appropriate fixtures and automatic recording devices, multiple tensile properties can be tested. However, because the inertia of the pendulum and the strain rate per unit time vary with the stress-strain characteristics of the material, the accuracy of the instrument is low and the comparability is poor. The representative of the equal load type instrument is the inclined plane strength machine, which can be used to determine the tensile properties of fibers and yarns. Among them, the electromechanical inclined plane strength machine can continuously and automatically stretch 10 bobbins according to the specified number of tests and exchange bobbins. At the same time, it can also draw graphs of breaking strength and breaking elongation. The instrument is equipped with a data processing system, which can directly print out the test results. At the end of the 1970s, a constant-speed elongation electronic full-automatic single-yarn strength meter was developed, which uses strain-type sensors to measure force, with high accuracy and automation, low inertia and full functions. According to the different capacity, it can be divided into general type and special type. The universal instrument can measure the tensile properties, elasticity and compressibility of fibers, yarns and fabrics by changing sensors of different capacities. If equipped with appropriate accessories, shear, bending and friction performance tests can also be carried out. This kind of instrument is sometimes called a universal strength tester, which can digitally display, automatically process data, and print out test results. Some models of instruments are also attached with high and low temperature test devices. The desktop single-fiber electronic strength tester (Figure 2) successfully developed in China is a special type with a maximum capacity of 100 grams force, which can be digitally displayed and automatically recorded, and some can also print out the average number of tensile properties and the coefficient of variation. In the 1980s, a fully automatic short fiber strength tester was made.
A variety of test results can be obtained by testing with a tensile property tester, such as breaking strength, breaking elongation, multiple tensile fatigue, constant load or constant elongation elasticity, and fabric tearing strength , Bursting strength, sewing strength, etc. In addition, the initial modulus, breaking power and other indicators can be obtained by calculation using the record drawing (see yarn strength).
Abrasion resistance test instrument
Abrasion resistance test can predict the abrasion resistance of textile materials in spinning, weaving and other processing procedures and the degree of wear resistance during wearing. Abrasion resistance testers are used for filament and staple fiber yarns, and also used for fabrics. There are many types of fabric abrasion resistance testers, including flat grinding (rotary, inflatable, reciprocating flat, reciprocating drum), curved grinding , Hemming grinding and accelerated grinding, etc. Figure 3 is a rotary fabric flat grinder. The wear motion mode and abrasives of the wear resistance tester are mostly designed to imitate the actual usage. The indicator of the wear resistance of textile materials is generally expressed by the number of wear to break, the change of certain properties (strength, weight, etc.) after a certain wear, or the number of wear resistance when the fabric wears holes.
Appearance quality tester
Used to test the appearance quality of yarns and printed and dyed fabrics. Appearance quality usually refers to yarn evenness, yarn defects, and dye fastness of printed and dyed fabrics. There are three methods for inspecting yarn evenness and yarn defects: eye evaluation method, weighing method and instrument method. The eye evaluation method only requires a simple blackboard shaker. The weighing method uses a semi-automatic electronic count balance, which can quickly weigh out the count of the fixed-length hank, and print out the average count and count unevenness. The instrument method mainly uses the Uster evenness tester.
Uster Evenness Tester
It is used to measure the evenness of cotton sliver, roving and spun yarn (Figure 4). The instrument is designed according to the principle that the capacitance changes with the linear density of the yarn when the yarn passes between the capacitor plates. This instrument was successfully developed by the Swiss Uster company in the 1940s, and later gradually developed various models. The B type is suitable for short fiber yarns such as cotton, wool, rayon and hemp yarn, and the C type is suitable for chemical fiber filaments and synthetic fiber yarns. Early instruments can automatically record the unevenness curve, and can integrate the average difference coefficient of the yarn sliver. The instrument that came out in the 1970s has high test efficiency and can automatically calibrate the zero point. The instrument in the 1980s can automatically change the bobbin, automatically adjust the average value, and automatically print out the coefficient of mean square error or coefficient of average difference. This instrument is also equipped with a spectrometer, which can draw a spectrum of yarn unevenness to analyze the uneven nature of the yarn and the cause of the unevenness; the neps and trash meter can determine the size of a certain length of yarn according to the specified size. Number of neps and impurities in cotton and wool yarns.
Dyeing and dyeing fabric fastness tester
It is used to test the degree of fading of printed and dyed fabrics after exposure to sunlight and friction. Most of them are designed to imitate the actual use of printed and dyed fabrics, such as light fastness tester, soap fastness tester, rubbing fastness tester, sublimation fastness tester and so on. The color fastness test method varies with the type of equipment.
Fabric style testing instrument
An instrument that tests certain physical and mechanical properties of fabrics to comprehensively evaluate fabric styles. The fabric style in a broad sense refers to the response of the fabric to human tactile and visual faculties; in a narrow sense, it only refers to the sense of touch, which is usually called the feel. Fabric style is also divided into value style and characteristic style. Value style refers to the aesthetics and comfort of clothing; characteristic style can be divided into single factor characteristic style (such as smooth, full, crisp, etc.) and multiple factor characteristic style (such as wool type) Sensation, silky sensuality, hemp-type sensation, etc.). Fabric style has always been evaluated by hand feel and visual inspection, and this method still occupies a dominant position. In 1930, the cantilever beam method was used to measure the bending length and bending stiffness of fabric samples to express the feel properties of the fabric. In the 1950s, American scholars proposed to use the maximum traction of a circular sample through the loop to express the feel of the fabric, and the early feel tester appeared. In the test, the sample is subjected to bending, compression and surface friction at the same time, so the measurement result has a comprehensive nature. In the early 1970s, Japanese scholar Kawabata Yoshio proposed that the fabric’s pure bendability, surface properties (coefficient of friction and roughness), stretchability (including shear), compressibility, etc. should be used to comprehensively reflect the fabric style, and consist of instruments that test these properties. KES-F series fabric style instrument. Using this series of four instruments to measure 16 indicators, evaluate basic style values such as stiff (scratched), smooth (sweet), and full (full) according to different uses of the fabric, and then input the computer to obtain the comprehensive style value. China has developed a fabric style instrument and corresponding testing methods. The instrument has a simple structure and good performance. The fabric is often subjected to various external forces during actual use, resulting in wrinkles, surface defects and dimensional changes, etc., which are closely related to the shape retention and surface uniformity of the clothing and belong to the range of fabric styles. Instruments for testing these properties include a wrinkle recovery angle tester, a surface uniformity tester, and a shrinkage rate tester. Donghua University (formerly China Textile University) has developed a new type of fabric drape tester (fabric style meter) that uses image processing methods to test the static and dynamic drape properties of fabrics. The drape performance index includes two parts: basic drape index and auxiliary drape index. The basic index is drape coefficient, wave number, crest amplitude uniformity, crest included angle uniformity, dynamic and static drape coefficient ratio. Auxiliary indexes are maximum crest amplitude and minimum crest. Amplitude, maximum crest angle, minimum crest angle and other indicators.
Fabric wrinkle recovery angle tester
Fold the fabric sample in half and apply pressure close to the weight of the human body (150-300 g/cm2) to make the sample form a crease. After acting for a certain period of time, press to restore the crease. The larger the recovery angle, the better the wrinkle resistance of the fabric. China has used semi-automatic fabric wrinkle elasticity tester.
Fabric surface uniformity tester
Fabric often fuzzing and pilling and snagging during taking, this phenomenon will obviously destroy the uniformity of the fabric surface, thereby affecting the appearance of the fabric quality. The fabric fuzzing and pilling instrument is roughly divided into two types: first fuzzing and then fuzzing and simultaneous fuzzing and pilling. The brush pilling instrument first uses a brush to rub the sample and then pilling with the same fabric or other standard abrasives in a soft state. Drum-type tumbling instrument and square box-type tumbling instrument place the sample in a box (or drum) to continuously roll and interact with the abrasive, and the fuzzing and pilling are completed in one step in the instrument. For fabric snagging tests, many countries use the mace-type snagging instrument. In China, besides the mace-type snagging instrument, there is also a needle-rolling snagging instrument.
Physical property testing instrument
An instrument for testing the air permeability, moisture permeability and electrical properties of textile materials. The tests of these properties can reflect the comfort and sanitation of the clothing fabrics when taken. There are air permeability tester, moisture permeability tester, warmth retention tester and fiber specific resistance tester, etc.
Air Permeability Tester
Some instruments use the amount of air per unit area of the fabric under a certain pressure to express the air permeability of the fabric; some instruments pass the fabric under a certain load The time required for a fixed volume of air to express the breathability of the fabric.
Moisture permeability tester
There are two types of evaporation method and absorption method: the evaporation method tester is to cover the container with water with a fabric sample to measure the water in the container The weight loss after evaporation through a certain sample area per unit time; the absorption method tester is to cover a container containing a desiccant with a fabric sample, and measure the desiccant in the container to absorb moisture through a certain sample area per unit time After the weight increase.
Heat retention tester
There are two types: the constant temperature method and the cooling method: the constant temperature method is to place both sides of the sample in a constant temperature source and a lower temperature environment, and measure for a certain period of time The heat lost through the sample is used to indicate the warmth retention of the fabric. The constant temperature source can generally be close to the temperature of the human body (35℃), and the low temperature environment is 21℃; the cooling method is to coat a container with warm water with a sample and place it in a low temperature environment to cool down, and measure the temperature required for each decrease in temperature. Time is used as an indicator of fabric warmth.
Fiber resistivity meter
There are two types of fiber resistivity meter: ①Fiber volume resistivity meter: Put a certain weight of fiber into a container and squeeze it into a certain volume before measuring Obtain the resistance value and find the fiber volume specific resistance value; ②Fiber mass specific resistance meter: clamp an appropriate number of fibers into two clamps at a certain distance, measure the resistance value with a high-insulation resistance meter, and then weigh the two clamps The fiber weight between the holders, and the fiber mass specific resistance value is calculated.
Technical property testing instrument
An instrument for testing technical properties such as fiber length, fineness, crimp, yarn twist, yarn hairiness and moisture regain. There are fiber length tester, fiber fineness tester, fiber crimp tester, yarn hairiness tester, yarn twist tester, moisture regain tester, etc.
Fiber Length Meter
An instrument for testing fiber straight length. At the beginning of the 20th century, people used the hand-pulling method to measure the length of the fiber bundle. In the early 1930s, the arranging and combing methods began to test the length. In the 1950s, manual adjustment and testing were used, and soon it was changed to servo motor automatic tracking. In the 1970s, the United States developed a new camera length meter, which can measure the length of cotton fiber and chemical fiber, up to 63 mm. In the 1980s, it has been further developed into digital display, automatic data processing and printing out related length indicators, and the test efficiency has been significantly improved. The Arealometer capacitive wool length meter produced in Belgium is equipped with an automatic fiber finishing mechanism, which can arrange the fibers into a neat bundle at one end. When the hair bundle is placed on the plastic film and passed through the electric field, the average length of the hairs and the weight-weighted average length can be obtained. This kind of instrument is only suitable for wool tops, and the error is relatively large when used for loose wool. The length of cotton fiber in China mainly uses a roller-type length tester. The fibers neatly arranged at one end are placed on the instrument, and the weight-weighted average length and other indicators are obtained after grouping and weighing at a certain interval. The length of wool fiber is generally measured with a comb length meter. The length of raw silk and chemical fiber filaments is measured with a yarn frame length gauge with a certain circumference.
Fiber Fineness Tester
The methods for testing fiber fineness are: ①Direct method: or mid-cut method, cut the fiber bundles of fixed length, parallel and straight, after weighing, After counting the number of fibers to calculate the metric count, denier or special number of a single fiber, only some simple weighing instruments are needed. ②Indirect method: There are airflow method and sound pressure method. When airflow or sound waves pass through a quantitative cluster of fiber aggregates, the air pressure and sound pressure change, and the magnitude of the change varies with the thickness of the fiber. Generally, the thinner the fiber, the more the air pressure and sound pressure decrease. Various types of airflow fineness meters based on this principle appeared in the early 1950s. Later, China developed a digital micro-pressure airflow fineness meter suitable for a variety of fibers. ③Vibration method: adopt the principle of string vibration to measure the natural vibration frequency of the fiber under a certain length and tension of the vibrating string, and automatically calculate the linear density of a single fiber by the string vibration formula, and obtain the linear density variation coefficient (reflecting the quality of fiber thickness distribution). Linear density unevenness). The vibrating fineness meter and the tensile strength meter are used online to calculate the specific strength, modulus and specific work of a single fiber related to the fiber linear density. It is the international chemical fiber inspection method standard (ISO5079-1995 and international chemical fiber standardization) The Bureau (BISFA) test method standard) recommends the preferred fiber strength test method, which represents the development direction of fiber testing. This test method is widely used internationally and basically replaces the original operation of the middle section weighing method to measure the fiber linear density. The fiber width tester measures the radial projection width of the fiber in its natural state. When the cross-section of the fiber is circular, this width corresponds to the fiber diameter. The diameter of wool fiber is used as the basis for quality evaluation. The fiber width or diameter is generally tested with a biological microscope or projector, but it is more troublesome and the efficiency is very low. Therefore, an instrument for measuring fiber diameter with a laser appeared. This instrument is designed based on the fact that when the fiber dispersed in the liquid stream passes through a 1 mm laser, the amount of laser scattering is proportional to the fiber diameter. With this instrument, the diameter and distribution of individual fibers can be measured.
Electrostatic meter
There are two types: friction type and induction type. The friction electrostatic meter is to directly measure the static voltage on the sample after the sample is triboelectrically generated; the induction electrostatic meter is to measure the static voltage or half-life of the sample after the sample is charged in an electric field.
Friction coefficient tester
There are many ways to determine the friction coefficient of fibers. Generally, the friction coefficient of short fibers is determined by the friction coefficient tester of the winch method. This kind of instrument is also called Rhodes (R? der) method friction coefficient tester. This instrument can not only test the coefficient of friction between fiber and fiber, but also test the coefficient of friction between fiber and metal, fiber and other materials (Figure 6). In addition, there are various types of friction coefficient testers for yarns and filaments. Since the 1980s, there has also been an internationally developed dynamic and static friction coefficient measuring instrument that can automatically measure and record.
Crimping tester
An instrument for measuring the number of crimps per unit length of fiber. There are generally two methods for measuring curling: visual inspection and projection. The mechanical crimp elasticity meter produced in Japan can measure the crimp rate and crimp elasticity. The fiber crimp elasticity meter (Figure 7) developed by China for measuring displacement by the grating method has high accuracy and has certain characteristics for measuring the crimp of chemical fiber short fibers. The new fiber crimp elasticity meter uses image processing method to automatically detect the fiber crimp number, eliminating the uncertainty of the measurement result caused by manually counting the fiber crimp through a magnifying glass.
Yarn Hairiness Tester
An instrument for testing short fiber yarn surface hairiness. Most of these instruments are designed using the principle of photoelectric counting. The hairiness tester produced in Japan can automatically count the number of hairiness and hairiness length, and can print the results. The instrument can measure staple fiber yarns below 3000 denier, the measurable hairiness length is 0-10 mm, and the yarn speed is 30 m/min. Another type of hairiness counter has two sensors, which can be used for both short fiber yarns and filaments below 1500 denier. Yarn speed is 10～1500m/min, four-digit display. There are also instruments that use dark field to detect hairiness, with high accuracy (0.2 mm), and the hairiness length can be divided into three levels of 3, 5, and 7 mm for detection. The photoelectric hairiness tester developed by China in the early 1980s has good performance.
Yarn twist meter
An instrument for testing the number of twists per unit length of the yarn and the twist shrinkage. There are two methods for testing yarn twist: complete untwisting method and "untwisting-twisting" method. The complete untwisting method is suitable for roving and strand yarn. The twist test of single yarn mostly adopts the "untwist-twist" method, and the instrument used is an electric twist meter. Since the end of the 1970s, the degree of automation of the twist meter has been significantly improved. Japan has a single fully automatic twist meter, which can continuously and automatically measure the twist value and print the result. Some automatic twist meters can test the twist by one-time untwisting-twisting method, double untwisting-twisting method and other methods. 10 bobbins can be automatically changed according to the specified number of tests, and the results are printed out.
Moisture regain tester
There are two types of direct drying and indirect measurement. In addition to the most commonly used ovens, direct drying also includes rapid drying using infrared, high frequency and microwave Dry instrument. The application of these fast dryers in textiles is still not very popular. There are mainly two types of indirect measuring instruments: resistance moisture meter and capacitance moisture meter. These two instruments are designed based on the principle that the resistance and dielectric constant of textile materials are related to the amount of moisture contained in the material. Among them, the resistance moisture meter has been widely used. Some countries have formulated a series to quickly determine the moisture regain of fibers, yarns, fabrics, and even sizing agents. Some instruments also have the function of controlling production. The resistance type raw cotton and cheese moisture regain tester made in China has been widely used in production and has good performance.
Fabric fabric testing equipment
Fabric strength tensile machine, zipper fatigue tester, fabric pilling tester, ICI pilling tester, button tension tester, zipper reciprocating fatigue test Machine, roller box pilling meter, moisture tester, fabric flat grinding meter, fabric thickness meter (fabric thickness meter, portable fabric thickness meter), fabric density mirror, fabric tearing meter, fabric weight meter, impact Button machine, cloth weight balance (fabric weight balance), sample cutter (Hong Kong sample cutter, domestic sample cutter), cutter (manual sample cutter), electronic yarn count detection system, universal resistance Grinding instrument, thermal and moisture resistance tester, PINKUI, air permeability tester, burst tester, light fastness tester, water permeability tester, moisture management system tester, printing and dyeing Color fastness textile instrument
Color fastness to perspiration tester, rubbing color fastness tester (rubbing color fastness tester, AATCC rotary rubbing color fastness tester), color fastness rubbing tester, Horizontal burning tester, vertical burning tester, 45 degree burning tester, washing fastness tester, shrinkage tester (domestic standard washing machine, AATCC standard washing machine (Whirlpool washing machine, Kenmore washing machine), AATCC standard clothes dryer ( Whirlpool clothes dryers, Kenmore clothes dryers), textile viscometers, textile coding machines,
universal textile inspection equipment
metal detectors (hand-held metal detectors) , Flat-panel metal detector, gantry metal detector), standard color matching light box (VerVideCAC60 color matching light box, UK VerVideCAC120 color matching light box, British VerVide color review light box CAC150, JudgeII imported standard light source color matching light box, SPECTRALIGHTⅢ American standard light box , SPLIII imported standard light source to color light box, LG-600 four light sources, LG-600 five light sources, LG-600 six light sources), needle detector (luxury desktop needle detector, double safety needle detector, anti-interference needle detector Machine, wide conveyor type needle detector), magnifying glass (three-fold magnifying glass, 40 times reading magnifying glass)
Textile simulation environment test instrument
Pointer push-pull force meter, digital display Push-pull force meter, digital display temperature and humidity meter, infrared thermometer, illuminance meter, noise meter, constant temperature and humidity box, drying box, wind speed thermometer, color difference meter, constant temperature incubator, temperature and humidity recorder
Textile testing consumables
AATCC white cotton cloth, European wash cloth, American standard wash cloth, Japanese standard stained gray ruler, Japanese standard faded gray ruler, European standard stained gray ruler, European standard faded gray ruler , American standard nine-level color chart, American standard stained gray ruler, American standard faded gray ruler, textile marker pen, faded pen, JAMESH.HEAL series (Jeams.H.Heal yellowing control film Jeams.H.Heal yellowing Control cloth Jeams. H.Heal yellowing test paper), American standard shrinkage scale, AATCC1993 detergent, 1993WOB detergent, AATCC multi-fiber cloth, AATCC nine-level colorimetric card, AATCC gray card, AATCC stained gray card, SDC soap powder, IEC(B) detergent, IEC(A) detergent, ECE(B) detergent, ECE(A) detergent, SDC standard friction cloth, SDC multi-fiber DW fabric, ISO/BS discoloration gray card, ISO/BS stain Color gray card, TPX color card, CU color card, AATCC friction cloth/code, AATCC friction cloth/box, stainless steel ball, rubber plate, stainless steel blade, yellowness test material, temperature test paper. In addition, it is often used in textile production. Use yarn tension meter, yarn speed meter, slurry moisture regain tester and roller pressure tester to test yarn tension, yarn feeding amount, moisture regain and roller pressure, so that the products produced can meet the quality requirements.