Can Valve Bags Hold Liquids Without Leakage?

1. Core Answer: Prerequisites for Leak-free Liquid Packaging in Valve Bags

• Materials should adopt a multi-layer composite structure (e.g., PET+AL+PA+PE, PVDC composite film), with an inner waterproof layer (PTFE film) or barrier layer to ensure corrosion resistance and impermeability.
• Valves need to be equipped with double-seal design (silicone + rubber sealing) or automatic airtight resealing system, which can close instantly after filling and withstand pressure above 0.5MPa.
• Match the characteristics of liquids: low-viscosity liquids (fruit juice, alcohol) focus on sealing performance; high-viscosity liquids (jam, lubricating oil) require optimized valve caliber; strong corrosive liquids (sulfuric acid, sodium hydroxide) should use PTFE valve materials.

2. Technical Logic & Practical Verification of Leak-proof Performance

• Technical Core: Solvent-free lamination technology prevents material delamination; heat-seal strength reaches over 20N/15mm, with external pressure resistance of 200KG. Combined with fixed bottom structure, it avoids damage caused by transportation bumps.
• Industry Cases: After using customized Valve Bags, a certain alcohol enterprise reduced its leakage rate from 5% to 0.1%; a sulfuric acid packaging project cut its loss rate from 8% to 2% after PVDC material optimization.
• Testing Standards: Pass sealing test (no leakage under 0.5MPa pressure), drop test and corrosion resistance test, complying with ISO9001, FDA or EU REACH regulations.

3. Pitfall Avoidance Guide: Selection, Usage & Manufacturer Choosing Tips

• Selection Key Points: Clarify liquid viscosity, corrosiveness and capacity requirements. Specifications ranging from 1L to 250L should correspond to valve types (leak-proof valves, quantitative valves). Food-grade products need to select materials with no solvent residue.
• Correct Usage: Check the integrity of the sealing film before filling; match the caliber of the filling machine; control temperature and duration for heat-seal types; avoid excessive extrusion or storage in high-temperature environments.
• Manufacturer Screening: Prioritize enterprises with closed-loop production lines integrating "injection molding - lamination - bag making". Pay attention to customization capabilities and after-sales response (24-hour solution + 48-hour on-site service).