Yarn twist measuring system
Yarn twist measuring system
Yarn twist is a crucial parameter in the textile industry, as it determines the quality and performance of textile products. Measuring yarn twist is important to ensure that the yarn is suitable for its intended use and to maintain consistency in production. In this article, we will discuss yarn twist measuring systems, including their principles, types, and applications.
Principles of Yarn Twist Measuring Systems:
Yarn twist is the number of turns per unit length of yarn. The twist direction can be either Z-twist (clockwise) or an S-twist (anti-clockwise). There are different methods to measure yarn twists, but all methods are based on the same principle of determining the number of twists in a given length of yarn.
There are two main types of twist measuring systems: direct and indirect. Direct systems measure the twist directly by counting the number of twists in a known length of yarn. Indirect systems measure twists by measuring the angle of twists in the yarn.
Direct Yarn Twist Measuring Systems:
Direct yarn twist measuring systems are the most commonly used systems in the textile industry. The systems count the number of twists in a known length of yarn. The most common direct twist measuring systems are the skein method, the twist tester, and the package tester.
Skein Method:
The skein method is a simple and widely used method for measuring yarn twists. In this method, a skein of yarn is made by winding a known length of yarn on a reel. The skein is then untwisted by hand, and the number of twists in the known length of yarn is counted. The twist per unit length is calculated by dividing the number of twists by the length of the yarn.
The skein method has some limitations. It is time-consuming and requires skilled workers. The accuracy of the method depends on the worker's ability to untwist the yarn uniformly.
Twist Tester:
A twist tester is a machine that measures the twist directly by rotating a known length of yarn and counting the number of twists. The machine consists of two clamps that hold the yarn at both ends. One clamp is fixed, and the other clamp rotates at a constant speed. The number of twists is measured by counting the number of turns made by the rotating clamp.
The twist tester is a precise and efficient method for measuring yarn twist. It is widely used in the textile industry, especially for quality control purposes. The machine can measure the twist in both Z and S directions.
Package Tester:
The package tester is a direct twist measuring system that measures the twist in a package of yarn. The machine measures the twist by rotating the package at a constant speed and counting the number of turns made by the yarn. The machine can measure the twist in both Z and S directions.
The package tester is an efficient method for measuring the twist of large quantities of yarn. It is commonly used in the textile industry for quality control purposes.
Indirect Yarn Twist Measuring Systems:
Indirect yarn twist measuring systems measure the twist by measuring the angle of twist in the yarn. The most common indirect twist measuring systems are the twist multiplier and the capacitance-type twist tester.
Twist Multiplier:
The twist multiplier is an indirect twist measuring system that measures the angle of twist in the yarn. The system consists of a light source, a mirror, and a lens. The light source is directed toward the yarn, and the reflected light is projected onto a screen. The angle of twist in the yarn is measured by the displacement of the image on the screen.
The twist multiplier is an accurate and efficient method for measuring the twist of fine yarns. The method is commonly used in research laboratories and quality control laboratories.
Capacitance Type Twist Tester:
A capacitance-type twist tester is an instrument used to measure the amount of twist or torsion applied to a material or component. It works based on the principle of measuring the change in capacitance that occurs as the material is twisted.
The instrument consists of two plates, one fixed and the other movable, separated by a small gap. The movable plate is connected to the material being tested, and as the material is twisted, the distance between the plates changes, altering the capacitance. This change in capacitance is then measured and recorded by the instrument, providing an indication of the amount of twist applied to the material.
Capacitance-type twist testers are commonly used in the manufacturing and testing of components such as cables, wires, and springs, where the amount of twist or torsion applied to the material is critical to its performance.
Determination of yarn twist:
A twist tester is a device used to determine the twist level of a yarn. The twist level is an important parameter of yarn, as it affects the strength, appearance, and behavior of the yarn in subsequent processes. Here are the general steps to determine yarn twist using a twist tester:
Cut a sample of yarn of a known length from the yarn to be tested.
Attach the ends of the yarn sample to the twist tester.
Set the twist tester to the appropriate gauge for the yarn being tested. This will depend on the yarn count or thickness of the yarn.
Insert the yarn sample into the twist tester and start the machine.
Observe the number of twists in the yarn sample. This can be determined by counting the number of turns in the yarn as it is being untwisted by the machine.
Calculate the twist per inch (TPI) or twist per meter (TPM) of the yarn sample by dividing the number of twists by the length of the sample.
The twist level required for a particular yarn will depend on the intended use of the yarn. A yarn with too little twist will be weak and prone to breaking, while a yarn with too much twist may be harsh and rough to the touch. The twist level can be adjusted by changing the spinning parameters during the production of the yarn.