In the field of textile technology, it is often necessary to measure the length of yarn. Currently, the main method for measuring yarn length involves manually straightening the yarn and then using a ruler to take the measurement. This method, which relies on manual straightening of the yarn, suffers from significant errors due to the inability to control the force applied during each measurement, and even greater variations in force applied by different workers.  Therefore, the accuracy of yarn length measurement is low.

Based on this, there is a need to provide a yarn length measuring device that can improve measurement accuracy.

A yarn length measuring device includes: a tension detection mechanism, comprising a tension detection body and a yarn fixing component, wherein the yarn fixing component includes a fixing part and a connecting part, the fixing part and the connecting part are positioned opposite each other and are used to connect the two ends of the yarn, and the tension detection body is connected to the connecting part and can move relative to the fixing part to apply tension to the yarn and detect the magnitude of the tension applied to the yarn; and a laser ranging mechanism, used to detect the distance between the fixing part and the connecting part when the tension applied to the yarn reaches a preset value.

In the above yarn length measuring device, the fixing component of the tension detection mechanism fixes both ends of the yarn, and the tension detection body moves relative to the fixing part to straighten the yarn and apply tension to the fixed yarn. The tension detection body detects the tension acting on the yarn. When the tension detection mechanism detects that the tension applied to the yarn reaches a preset value, the laser ranging mechanism detects the distance between the fixing part and the connecting part. In this way, during yarn length measurement, the tension detection mechanism ensures that the tension applied to the yarn is the same during each measurement, and the laser ranging mechanism accurately measures the length of the yarn, avoiding the problem of large measurement errors caused by uncontrolled measurement force, thus improving measurement accuracy.

In the textile industry, yarn is spun into strands, which are called "strands of yarn" or "skeins of yarn" in some regions. These strands can be used to test indicators such as yarn length, breaking strength, and elongation. One piece of professional laboratory equipment is the yarn length measuring instrument, also known as a yarn length tester. This instrument is one of the devices used to evaluate the linear density technical indicators of yarns and filaments. Some foreign users also use it for sample preparation for yarn strength testing. It is widely used in the central laboratories of textile enterprises, testing institutions, quality inspection and enforcement units, and research institutions.

What is a Skein?

A skein is yarn wound into a hank of a specified length and number of turns from a cone or bobbin. Its shape is suitable for inspection and dyeing and finishing processes, and facilitates packaging, transportation, and storage. Skein dyeing is a dyeing method where staple fiber yarn or filament yarn is transformed into interconnected hanks on a reeling machine, and then dyed by immersion in various types of dyeing machines.

There are various forms of skeins, such as straight-wound skeins and fancy-wound skeins, each suitable for different yarns and dyeing and finishing requirements. Straight-wound skeins are mostly used for dyeing, bleaching, and selling wool yarn, while fancy-wound skeins are mostly used for dyeing, bleaching, and selling cotton yarn and silk. Because skeins can be packaged tightly, facilitating transportation and storage, cotton yarn, wool yarn, and silk are often sold in skein form.

Process of Skein Dyeing

The process of skein dyeing includes the following key steps:

Reeling process: The yarn is unwound from the cone or bobbin using a reeling machine and then rewound into a skein structure according to preset parameters.

Quality inspection: The standardized winding form of the skein facilitates the sampling of yarn in the laboratory for testing key quality indicators such as yarn strength, evenness, and moisture regain.

Dyeing process: Skein dyeing is a dyeing method where staple fiber yarn or filament yarn is transformed into interconnected hanks on a reeling machine, and then dyed by immersion in various types of dyeing machines.

Because skeins can be packaged into small and compact packages, which is beneficial for transportation and storage, cotton yarn, wool yarn, and silk are often made into skeins for packaging and sale.

Working Principle

The instrument drives the yarn frame to rotate through a motor, winding the yarn into a set number of turns (2-9999 turns can be preset), and the speed can be continuously adjusted (30-280 revolutions/minute). After winding, the yarn weight is measured, and the linear density (such as Tex = mass/length × 1000) is calculated based on the number of turns and the length per turn. Some models support soft start and slow stop functions to avoid yarn breakage and ensure smooth operation without additional tension impact.

The operating procedure 

Turn on the instrument's power switch, click "Parameter Settings," and set the parameters according to the standard and the nominal linear density of the yarn.

Set the appropriate number of turns and the number of bobbins.

After setting the parameters, enter the test interface and click "Reset."

Adjust the pretension according to the nominal linear density of the yarn.

Perform a pre-test, select a sample according to the standard, and adjust the sample.

Insert the yarn bobbin onto the bobbin holder, and discard the first few meters of yarn.

Thread the yarn through the tension regulator, tension sensor rod, and traverse guide hook, and clamp the yarn into the yarn clamp.

Return the blade to its original position and click "Start."

The machine will automatically stop when the yarn roll reaches the set number of turns. Remove the yarn, weigh the sample, and calculate the actual pretension.

Adjust the tension weight accordingly and perform the formal test using the same method.

The above steps can help users correctly operate the yarn length tester, ensuring the accuracy and reliability of the test results.

In summary, whether it's the innovative yarn length measuring device, the traditional and widely used skein length testing instrument, or the hank method with its unique process characteristics, they all play an indispensable role in the field of textile technology. From precisely measuring yarn length to comprehensively testing various key indicators of yarn, and facilitating the inspection, processing, transportation, and storage of yarn, these methods and technologies continuously drive the progress and development of the textile industry. With the continuous innovation of technology, it is believed that more advanced and efficient textile technologies will emerge in the future, injecting new vitality into the upgrading and transformation of the textile industry and helping the textile industry move towards a higher quality development stage.