Raw Material Standards
The main raw material for flexible FIBCs (Flexible Intermediate Bulk Containers) is plastic flat yarn such as polypropylene (PP) or polyethylene (PE). These raw materials should possess good physical properties, such as sufficient strength, toughness, and aging resistance. The purity of the raw materials must be high, and they should not contain excessive impurities, otherwise it will affect the overall quality of the FIBC. For example, impurities may cause the flat yarn to break during weaving, reducing the strength of the FIBC.
Weaving Process Standards
The weaving process directly affects the strength and appearance of the FIBC. The weaving density should meet relevant standards. Generally, the weaving density per 100mm × 100mm should reach a certain value to ensure that the FIBC has sufficient load-bearing capacity. The warp and weft threads should be uniform and tight, without defects such as missing warp or weft threads, or skipped stitches. In addition, the surface of the woven bag should be flat, without obvious wrinkles or damage.
Sewing Standards
The sewing quality of the FIBC is also crucial. High-strength, abrasion-resistant materials such as polyester thread should be used for sewing. The stitch spacing should be uniform, and the number of stitches per 100mm should generally be within the specified range. The stitching must be secure, especially the connection between the lifting straps and the bag body, which must be able to withstand a certain tensile force to prevent breakage during lifting.
Physical Performance Standards
Flexible intermediary bags (FIBCs) need to possess certain physical properties. For example, their tensile strength should meet requirements, enabling them to withstand the weight of the loaded goods without breaking. Tear resistance is also an important indicator; during loading, unloading, and transportation, FIBCs may be scratched by sharp objects, and good tear resistance can prevent damage. Furthermore, FIBCs should also have a certain degree of UV resistance to adapt to different storage and transportation environments.