Assembly and sewing of EVA tool bags

Assembly and sewing of EVA tool bags

EVA tool bags are favored by many international wholesale buyers for their excellent performance such as lightness, durability, waterproofness and shockproofness. Whether it is outdoor adventure, industrial maintenance or daily home use, EVA tool bags can meet diverse usage needs.

1. Assembly process of EVA tool bags
(I) Raw material preparation and pretreatment
The production of EVA tool bags starts with the selection of high-quality raw materials. EVA material itself has good softness, elasticity and chemical stability. During the production process, it is necessary to select EVA sheets of appropriate thickness, hardness and color according to product requirements, and match them with auxiliary materials such as zippers, webbing, hardware buckles, etc. Some EVA materials also need to be pretreated before use, such as pre-pressing or surface treatment, to improve printing or bonding effects.
(II) Lamination and cutting
Laminating the fabric and lining with EVA materials is one of the key steps. Glue or hot melt technology is usually used to tightly fit the layers of materials to form a multi-layer structure. The laminated materials need to be dried to remove moisture, and then cut into small pieces of the required size according to the design drawings. This step relies on a die cutter or a vertical cutter to ensure that the edges are smooth.
(III) Molding process
The molding process is the core step in the production of EVA tool bags. The cut EVA sheets are placed in an oven for baking (temperature is about 130°C), and then pressed and shaped by a cold press. The mold design needs to match the bag structure, and complex parts need to be customized with multiple sets of molds. The pressed product needs to be placed for a period of time, and it can be cut after it is completely cooled.
(IV) Assembly
In the assembly stage, the various parts need to be spliced. Some hardware accessories such as D-rings and buckles will be installed on the bags first, and riveting or ultrasonic welding may be used. Splicing and stitching mainly use high-frequency welding or sewing. High-frequency welding uses a high-frequency machine to heat the EVA seams to fuse them, without stitching, and has good waterproof properties; sewing uses an industrial sewing machine to sew the edges, and waterproof thread or tape is used to seal the pinholes.

2. Sewing process of EVA tool bags
(I) Preparation before sewing
Before sewing, make sure all materials and equipment are ready. Choosing the right EVA material and suture is the basis. At the same time, the material must be pre-processed as necessary, such as cutting and grinding. In addition, cleaning work should not be ignored. Before assembly, make sure all surfaces are clean and dust-free.
(II) Sewing skills
During the sewing process, pay attention to the following tips:
Suture tension control: Ensure that the suture tension is uniform to avoid wrinkling or uneven sutures.
Sewing machine settings: Adjust the stitches and speed of the sewing machine according to the thickness and type of the material to achieve the best sewing effect.
Suture color matching: Choose sutures that match the color of the EVA material to enhance the aesthetics of the product.
Reinforcement treatment: Reinforcement sewing is performed in key areas such as handles and pockets to ensure the durability of the product.
(III) Quality control
After sewing, strict quality inspection is required. Check the firmness and flatness of the sutures. Problems found, such as loose sutures and skipped stitches, should be repaired in a timely manner. Only products that have undergone strict quality inspection can ensure their reliability and durability during use.

3. Strategies to improve assembly and sewing efficiency
(I) Mold reuse and simplified design
By simplifying the design, reducing the number of molds, or using universal molds to adapt to multiple products, production costs can be effectively reduced and production efficiency can be improved. This not only reduces the frequency of mold replacement, but also shortens production preparation time.
(II) Batch production
Stamping and cold pressing technologies are suitable for large-volume orders. Through batch production, the production capacity of the equipment can be fully utilized and the production cost per unit product can be reduced. At the same time, batch production can also improve the stability and consistency of the production process.
(III) Application of intelligent equipment
The introduction of intelligent equipment such as CNC die cutting can improve production efficiency and precision. These equipment can accurately perform cutting and molding operations and reduce manual errors. In addition, intelligent equipment can also realize automated production and further improve production efficiency.
(IV) Environmental improvement
During the production process, use degradable glue or recycle scraps to reduce the waste rate. This not only helps environmental protection, but also reduces production costs. At the same time, the use of environmentally friendly materials also meets the requirements of the international market for sustainable development.