To ensure the quality and stability of the welding wire paper barrels, it is necessary to implement the following measures from four core dimensions: raw material control, process strictness, structural reinforcement, and finished product inspection. These measures should fully meet the core requirements of preventing moisture, pressure resistance, and damage during the storage and transportation of welding wire. The specific measures are as follows:
Control raw materials from the source to lay a solid foundation
The raw materials are the prerequisite for quality. Precise selection and pre-treatment are necessary. Preferentially use 250-350g/m² fully wood-pulp kraft paper or high-strength boxboard to ensure that the paperboard is free of impurities, no layering, and meets the stiffness requirements. Reject recycled mixed paper; During cutting, strictly control the size tolerance, with an error of no more than ±2mm to avoid misalignment during barrel assembly. The key pre-treatment step must be double-sided coating, using waterproof PE film, covering both the inner and outer barrel walls, to fundamentally enhance the moisture resistance and prevent the welding wire from getting damp and rusting; The adhesive used for fixation is an environmentally friendly polyvinyl alcohol solution, which is applied evenly without any missed coating, ensuring no air bubbles and maintaining both strength and environmental friendliness.
Control the forming process to ensure structural integrity
The barrel formation directly affects stability. Focus on the double-layer structure and precision control. Adhere to the double-layer wall design, with the inner and outer barrel walls bending and closing separately, and the connection point using "glue bonding + industrial staples for double fixation" to prevent delamination; Ensure the concentricity deviation is ≤5mm during assembly, with the inner and outer walls tightly adhering without loosening, to enhance the overall pressure resistance. During bending formation, strictly control the accuracy of the crease, without dead folds or damages, to avoid stress concentration leading to later pressure cracking, ensuring the barrel body is round and upright without distortion.
Strengthen assembly reinforcement to enhance durability
Targeted reinforcement of weak parts is carried out in the assembly process to meet the requirements of storage and transportation stacking and handling. The connection between the barrel bottom and the barrel body needs to be "fully glued + dense staples" fixed, with the staple spacing not exceeding 2cm to prevent detachment at the bottom; The barrel mouth is a vulnerable part, and round paper barrels must be equipped with galvanized iron hoops to prevent rust and enhance the pressure resistance of the opening, to prevent deformation during handling; For paper barrels that need to be lifted, non-metallic high-strength lifting rings are provided to avoid lifting breakage. The barrel cover adopts a folding + locking ring design to ensure a tight seal, which can prevent dust and water vapor from entering and also prevent the barrel cover from collapsing when stacked, further ensuring the sealingity and stability.
Comprehensive inspection throughout the process to守住 the factory bottom line
Finished product inspection should be comprehensive and in accordance with the GB/T 14187 standard. The appearance inspection： no dents， glue separation， curled coating， or blurred labels， no scratches or damages on the barrel body； Dimension re-inspection： the diameter， height， and wall thickness tolerances comply with the drawing requirements， and the concentricity does not exceed the limit； Performance tests： pressure stacking test (simulating storage and transportation stacking， with a pressure standard that does not collapse)， impact test (no damage or glue separation during drop)， and moisture resistance test (moisture resistance meets the standard under sealed conditions)； The sampling ratio is no less than 3%， and non-conforming products must not be allowed to leave the factory， avoiding storage risks from the source.
Additional auxiliary guarantees
During storage， it should be placed in a dry and ventilated environment to avoid the paperboard absorbing moisture and becoming soft； During the production process， the environmental humidity is strictly controlled (maintaining 40% - 60%)， to prevent the paperboard from absorbing moisture and deforming， further maintaining the stability of the paper barrel.