Ton bag, also known as container bag, space bag, etc., is a medium-sized bulk container and a type of container unit equipment. When equipped with a crane or forklift, containerized unit transportation can be achieved. It is convenient for shipping bulk powdery materials. It has the characteristics of large volume, light weight, and easy loading and unloading. It is one of the common packaging materials. It is characterized by simple structure, light weight, foldability, small space for emptying, and low price; it can carry 0.5-2 tons and is generally a rectangular structure. Ton bag is a flexible transportation packaging container, which is widely used for transportation and packaging of powdery, granular and lumpy items such as food, grain, medicine, chemicals and mineral products. Developed countries generally use FIBC bags as packaging for transportation and storage. product.
- Base fabric material
When designing a FIBC bag, first understand the weight of the loaded goods, and determine the volume of the ton bag according to the specific gravity of the loaded materials. It also depends on whether the loading materials contain sharp and solid block materials. If so, when designing the ton bag, the base fabric should be thicker, otherwise it can be thinner. In practical design, for ton bags with a load of 500kg, the base fabric is generally selected (150-170) G/m2, the longitudinal and transverse tensile strength of the base fabric is (1470-1700) N/5cm, and the elongation is 20-35%. Ton bags with a load of more than 1000kg. The base fabric generally uses (170~210) G/m2, the longitudinal and transverse tensile strength of the base fabric (1700-2000) N/5cm, and the elongation rate is 20~35%. - Structural design
When designing the structure of the FIBC bag, the national standard stipulates that the strength of the waist cuff should be more than twice the strength of the base fabric. However, in practice, the design effect is not good because the base fabric and the waist cuff have different strengths, causing the base fabric to crack first. During design, the waist cuff and the base fabric should be made of base fabric materials with opposite strengths to avoid this problem. - Sewing process
In addition to the sewing requirements according to national standard rules, FIBC bags also need to consider the aging resistance of the stitches and the impact of the stitches on the tensile strength of the base fabric. When packaging powdery, toxic, or contaminated items, the sealing problem must be dealt with first. Therefore, in practical design, ton bags are sewn with thick threads and fine needles or non-woven fabrics and base fabrics to ensure the sealing of the bags. In addition, when sewing FIBC bags, it is required to use polyester threads with a strength of more than 18kg to ensure that the sewing strength meets the national standard requirements. - Monofilament strength
To ensure the strength of the base fabric of the FIBC bag, the tensile strength of the flat yarn must be ensured. The perceptual strength of flat yarn should be above 0.4N/tex, and the elongation should be 15-30%. In the actual production and processing process, the amount of filler masterbatch needs to be strictly controlled, generally around 2%. If the masterbatch is added excessively or recycled materials are added, the strength of the base fabric will be reduced. Therefore, the quality of raw materials must be strictly controlled. Ton bags must use drawing raw materials from manufacturers whose melt index reaches the national standard. - Sling material selection
In FIBC bag design, the selection of strap materials is crucial. The national standard clearly stipulates a safety factor of 1:6. In the actual design of ton bags, firstly, the loss of strength of the sling caused by the sewing process must be considered, and secondly, the lifting method must be considered. For example, for a ton bag with a load of 500kg, the sling generally uses (50-60) g/m, and the tensile force is (1300-1800) N/m; for a ton bag with a load of 1000kg, (60-75) g/m is generally used, and the tensile force is (1800-2100) )N/m, the sling must meet the weaving density requirements. When designing slings for ton bags, two-ring or four-ring methods can be used to increase the tensile strength. - Whether to add additives
In order to stabilize the anti-aging performance of the plastic FIBC bag under sunlight, a certain amount of anti-violet agent and stabilizer must be added during the flat yarn drawing process. The amount of addition is determined according to the service life of the ton bag (half a year or one year), usually between (0.1~3)%. Some companies will add anti-aging masterbatch mixed with stabilizers, anti-violet agents and other additives, and the effect is also very good.
