Multi-layer kraft paper valve bags are high-end automated packaging products specifically designed for industrial powders and granular materials. These bags feature a composite structure of three layers of paper and one layer of film, combined with a square valve and three-dimensional square bottom design for compatibility with fully automated filling machines.

The bags provide high strength and excellent sealing performance, ensuring dust-free operations without powder leakage. Their neat stacking capability enhances storage and transportation efficiency, making them ideal for packaging materials weighing 25-50kg in industries including metallurgy alloys, refractory materials, chemical powders, and construction additives.

• Dust-Free Filling, Zero Powder Leakage: Dedicated valve design compatible with automatic impeller-type and gravity filling machines ensures rapid air discharge without powder spillage, eliminating workshop dust pollution.
• High Strength and Durability: Multi-layer kraft paper composite with thickened inner film provides excellent resistance against tearing, puncturing, and dropping, minimizing transportation damage.
• Moisture-Proof and Anti-Oxidation: Built-in waterproof barrier inner film blocks air and moisture intrusion, preventing deterioration of sensitive materials like vanadium-nitrogen alloy and refractory fine powders.
• Neat Form and High Storage Utilization: Pasted flat-bottom design maintains square, upright shape for even stacking without slipping, maximizing warehouse space and facilitating forklift handling.
• Cost Reduction and Efficiency Improvement: Highly adaptable to fully automated filling, eliminating manual sewing or sealing, boosting packaging efficiency and saving labor costs.
• Environmentally Friendly and Recyclable: Made from degradable, recyclable high-strength kraft paper without harmful additives, meeting environmental compliance requirements.

• Material Requirements: All materials comply with industry standards and are tailored to specific application scenarios and operational conditions.
• Valve Neck Process Technology: Advanced valve neck molding precisely controls material flow rate, enhancing sealing and compatibility across various filling, transportation, and storage environments.
• Physical Performance: Adequate strength, toughness, and environmental resistance to withstand moisture, compression, tearing, and impact factors.
• Printing Requirements: High-definition printing ensures clear, vivid graphics and text with uniform color distribution for perfect brand presentation.
• Dimensional Accuracy: Strict control over product dimensions with minimal tolerance errors ensures perfect compatibility with various filling equipment.

• Metallurgical Alloy Industry: Specially designed for powdered and granular ferrous alloy materials including vanadium-nitrogen alloys, ferromolybdenum, silico-calcium alloys, ferrosilicon, and rare earth alloys.
• Refractory Materials Industry: Suitable for refractory castables, high alumina powders, refractory mud, fireproof powders, and insulating mortars with excellent moisture and dust resistance.
• Chemical and Building Materials Industry: Compatible with various industrial dry powder materials including dry mortar, putty powder, calcium carbonate, talc powder, and chemical additives.
• Agricultural, Food, and Feed Industries: Customizable food-grade materials for clean packaging applications involving fertilizers, feed powders, and food raw material powders.

• Size Customization: Non-standard sizes from 20kg to 50kg tailored to fit both small and large filling equipment
• Layer Customization: Options include 2-layer, 3-layer, or 4-layer kraft paper to adjust strength and toughness
• Inner Film Customization: Choices between standard PE waterproof liners and reinforced thicker liners
• Printing Customization: Company logos, names, contact information, product specifications, and multicolor graphical prints
• Process Customization: Features such as anti-slip treatment, waterproof lamination, reinforced valve openings, thickened bag bottoms, and abrasion resistance
• Packaging Customization: Adjustments on full package quantity, packing methods, pallet packaging, and customized outer cartons