The sewing machine is a device for sewing plastic woven bags (objects), paper bags (objects), paper-plastic composite bags (objects), aluminum-coated paper bags and other bags with thread.

The sewing machine mainly completes the stitching and seaming of bags or woven fabrics. The process is characterized by good sealing performance after stitching, such as a flour bag; high strength, such as a cement bag; easy to disassemble, it will be loosened when the thread tail is found, and the bag can be reused. The domestically-made general model is GK. GK series industrial sewing machines, and imported DS series produced by Japan's Newland Company and made in the United States. According to the stitches, there are two kinds of single-thread chain type and double-thread chain type. According to the number of needles, it is divided into single needle and double needle. According to the usage, it is divided into desktop sewing machine, portable sewing machine, and vertical sewing machine. The domestic portable sewing machine is mainly the GK9 series, which has been used for many years. In addition, there are domestic portable sewing machines that imitate Japan and Germany; the foreign brand is the Japanese Newland NP series, including single-thread and double-thread portable. The most popular domestic vertical sewing machine is the GK35 series, which is an imitation of German products and belongs to the low-end products, while the high-end products are from Japan.

Requirements f sewing machine:
The hand-held sewing machine is a hand-held sewing machine, which is flexible and simple, but the labor intensity of workers is large and the productivity is low. Because it is a single thread, the strength after sewing is lower. And once the thread is continuous or the sewing is poor, the bag mouth will be affected. open. The vertical sewing machine should form an assembly line with the conveyor and be used in conjunction. In a relatively high-automated factory, the sewing machine must be combined with a packaging scale, a folding machine, a printer, and a palletizing device. It can realize high-speed, unmanned highly automated weighing and packaging.