I Events
The Chinese textile machinery market urgently needs the innovation of jacquard loom technology
1. The impact of the development of the domestic textile industry on the jacquard harness market
China is a major textile country. In 2006, there were nearly 40,000 enterprises above designated size in the textile industry in my country, an increase of nearly 10% over the same period in 2005; the cumulative total industrial output value was 2.5 trillion yuan, a year-on-year increase of 21.24%; the cumulative total realized profit was 88.294 billion yuan , An increase of 27.96% year-on-year. According to customs statistics: in 2006, my country’s textile and clothing exports totaled US$147.085 billion, an increase of 25.14% year-on-year, accounting for 15.18% of the country’s total foreign trade exports. my country's textile fiber processing volume accounts for more than 36% of the global fiber processing volume. In 2007, driven by the sound development of the national economy, it is expected that the textile industry will maintain a healthy, stable and rapid development, and the output value and exports will maintain a growth of about 20%. The textile industry is still one of my country's main pillar industries. With the continuous improvement of people's living standards, the domestic and foreign demand for textiles has gradually evolved from an increase in quantity to an improvement in quality. The production of high-quality textiles requires high-quality weaving equipment, and high-quality weaving equipment requires high-quality accessories to operate efficiently. As an important auxiliary accessory on the jacquard loom, the jacquard thong thread plays a very important role in the production of high-quality jacquard fabrics.
According to the survey, there are currently more than 200,000 jacquard looms in China. If each loom is equipped with 5,000×3m/each variety harnesses, and two varieties are replaced each year, the national average annual The demand for harness wires of 1850 tons (imported harness wires up to 200 tons) is even more astonishing if the demand for harness wires from abroad is added. It is worth noting that imported harnesses are expensive, generally between 350,000 to 400,000 yuan/ton, which is eight times the average price of domestic harnesses. Therefore, the development of high-quality harnesses has broad application prospects and economic value at home and abroad.
2. The rapid development of the weaving industry has triggered technological innovation in jacquard harness manufacturing
There are nearly ten manufacturers of jacquard harnesses in my country, most of them are small enterprises operating in the mode of family workshops, with large personnel turnover, relatively backward equipment, unstable product quality, and customers have strong feedback on product quality. In view of the fact that most of the domestic jacquard looms are low-speed, narrow shuttle looms, each jacquard loom requires a small number of harnesses and short lengths, so the quality requirements for harnesses are not high. For a long time, most of the harnesses of domestic jacquard looms have been made of vinylon. Vinylon has always been the material of choice for jacquard harnesses because of its relatively low price, relatively high strength, high modulus, durability and ability to adapt to various environments. Vinylon harness is basically suitable for weaving on low-speed, narrow-width looms.
However, since the 1980s, Chinese textile enterprises have begun to introduce, manufacture and use a large number of high-speed, wide-width jacquard looms. The speed of the loom has been increased from 100 rpm to 250-300 rpm. Imported high-speed jacquard The machine has reached 600 rpm, and the width of the loom has also been widened from 1.1 meters to 4.6 meters wide. As the key component of the opening mechanism of the jacquard loom, the harness wire has greatly increased its length and number, and the quality and technical index requirements (such as strength, modulus, wear resistance, etc.) have also been greatly improved.
The harness is one of the opening parts of the jacquard loom. Depending on the width of the loom, a jacquard loom requires thousands or even tens of thousands of harnesses, each with a length of 2 to 4.6 meters; Wide, the more harnesses on the loom, the longer the required length. When weaving on a loom, each harness wire has to open and close the shed through hundreds of thousands of repeated lifting movements a day, that is, the harness is subjected to hundreds of thousands of stretching and friction a day. Repeated stretching tends to cause the harness to fatigue, and the stretch rate of the harness is easy to change; repeated friction easily causes the harness to fuzz and damage until it breaks; in addition, the humidity changes in the workshop, for those that are easy to absorb and dehumidify. As far as silk is concerned, it will cause uneven expansion and contraction of the harness, which will affect the clear opening of the loom's shed.
At the end of the last century, with the increase in the width and speed of jacquard looms, companies that have long been accustomed to using vinylon harnesses began to find that the frequency of unclear shed openings on looms has gradually increased, and the resulting weaving defects have increased unabated. Especially when the Jiangnan area encounters the yellow mold season, the unclear shed can seriously affect the normal weaving of the loom, which has a great impact on the quality of the product. In the end, the factory has to cut all the harnesses and reinstall them. Cause certain economic losses to customers.
What caused ? The answer is: the number of harnesses on the loom increases, and the length increases, but the quality of the harnesses used does not increase simultaneously. The traditional vinylon harnesses are beginning to be unsuitable. More precisely, it starts with vinylon harnesses produced by traditional technology. It is not suitable for the weaving of high-speed, wide-width jacquard looms, mainly in: (1) Vinylon thong yarn produced by traditional technology is easy to absorb and dehumidify, and its high sensitivity to changes in air humidity makes it more sensitive to changes in air humidity. In the environment, even if the load is small, the expansion rate changes greatly; and the tens of thousands of densely packed harness wires above the loom will cause uneven moisture absorption and dehumidification due to the difference in surrounding conditions, which will cause different positions. The difference in the elasticity of the harness causes the shed of the loom to be unclear, and it is easy to form weaving defects, which affects the quality of the fabric product and reduces the weaving efficiency of the loom. Especially those small weaving factories or workshops usually lack effective control of the temperature and humidity in the weaving workshop. When the weather is humid, rainy or dry, there is little difference between the temperature and humidity in the workshop and the outside, and the above situation has a particularly large impact; (2) ) Vinylon harness produced by traditional technology has a certain lack of abrasion resistance under high-speed weaving conditions. After a period of use, it may be fluffed and damaged, which affects its breaking strength.
At that time, the defects of the domestic vinylon harness's higher expansion rate and uneven expansion rate were very prominent contradictions with the high speed, wide width, and high quality of the loom, which became the bottleneck for the development of jacquard fabrics and the improvement of fabric grades. Therefore, only by supporting high-quality harnesses as soon as possible, the expensive jacquard looms can show their talents, its weaving efficiency can be effectively improved, and the high added value of its products can be guaranteed. With the further development of jacquard looms in the direction of high speed and wide width, the market's demand for high-quality harnesses (high strength, wear resistance, and low expansion rate) is increasing day by day.
How to make the harness we use adapt to the weaving of high-speed, wide-width jacquard looms? The simplest answer is to buy imported harnesses, but that is almost eight times the high price of domestic harnesses. For most textile companies with less than 5% profit at present, they can only be discouraged; the only way out is to use their own scientific and technological power to improve the The quality of the silk can be improved at the least cost to improve the fabric quality of the jacquard loom, which may bring us higher added value, and improve the weaving efficiency of the loom. Obviously, it is inevitable to develop high-quality domestic harness based on its own, and to promote its application to modern high-speed, wide-width jacquard looms, which has a positive and far-reaching significance.