The global consumption of fibers is constantly increasing. This trend is partly due to the increasing demand for staple fiber yarns. The fiber consumption among spinning companies in 2016 was around 50 million tons. Thereby worldwide 250 million short staple spindles and 30,000 long staple spindles consume around 50 million tons of staple fibers. The fiber consumption is likely to increase even further over the coming years.
Groz-Beckert wires are indispensable for carding the fibers in spinning operations. While fibers with a staple length of 60 mm and above are processed in long staple spinning mills, fibers with a staple length of less than 60 mm are processed in short staple spinning mills. In the production of short and long staple yarns, the carding process is decisive for the quality of the yarn: Although the carding process is carried out with roller cards in long staple spinning and revolving flat cards in short staple spinning, Groz-Beckert card clothing is equally important in both.
Carding in long staple spinning
In the beginnings of fiber processing, mainly wool, wool-like fibers and natural fibers with longer fiber lengths were carded. From this developed the long staple spinning technology which today makes up a low market share with around 30,000 spindles only, compared with short staple spinning. This is due mainly to high raw material prices: While the price of wool is between 10 and 13 US dollars per kilogram, cotton and polyester fibers are comparatively cheap at a value of 1.7–2.5 US dollars per kilogram. Typical end products of long staple spinning include carpet yarns, high-quality suits and clothing for women and men. Today, synthetic raw materials like polyester, acrylic and polyamide fibers are also used.
In the carding process the spinner pays high attention on maintaining the fiber length, which is also reflected in the value of the yarns. In this field, Groz-Beckert offers both metallic card clothing such as licker-in wires, worker and doffer wires, as well as flexible card clothing. These are specially adapted to the requirements of the spinning industry. The unique SiroLock® card clothing from Groz-Beckert was originally developed for long staple spinning to maintain the valuable fiber length of wool. Today, the SiroLock® card clothing makes a significant contribution to increasing the fiber yield.
Carding in short staple spinning
Short staple spinning originates from cotton fiber processing. This still plays a key role today; increasingly, synthetic fibers such as polyester or rayon are also carded. While the share of cotton stagnates, the share of synthetic fibers is constantly increasing. The production process for yarns starts in the blowroom. Here, the fiber bales are opened, cleaned and the desired fiber blends created. The product range of Groz-Beckert includes special blowroom wires that guarantee good cleaning and opening performance of the blowroom machines. Once the fibers have been opened and blended, they are fed to the card. In the card, the separation and parallelization of the fibers – named carding – takes place. Starting with the licker-in wire, single fibers are released from the fiber mat and transferred to the cylinder. Together with the revolving tops and stationary flats main carding work takes place on the cylinder.
Groz-Beckert offers a wide range of cylinder wires, revolving tops and stationary flats which can be used for various applications. The doffer wire then takes the fibers from the cylinder and passes them on to the downstream processes. For processing synthetic fibers in particular, Groz-Beckert offers a special synthetic doffer wire D40-30-52C CBF with a curved tooth profile. This achieves a better fiber transfer from the cylinder to the doffer, thus creating an improved yarn quality and higher efficiency of the revolving flat card. The product of the revolving flat card is a carded sliver, which is processed into a roving in the downstream processes and finally spun into yarn.
Well carded is half spun
The quality of the yarn largely depends on the quality of the carding process. The optimal card clothing selection, in conjunction with the optimal card setting, guarantees a high fiber yield and avoids fiber damage. When opening fiber tufts to individual fibers, foreign particles are removed and neps are opened or eliminated. Both factors are extremely important for the quality of the yarn, which is why the phrase “Well carded is half spun” is common in the spinning industry. There are many application fields for the spun yarn, ranging from weaving, knitting and warp knitting, to sewing and embroidery. For you as a customer, Groz-Beckert offers the right card clothing for a wide range of applications.