Rusting of Stitching Pins in Corrugated Boxes — Why It Happens and How ASPV Prevents It
A Small Component That Creates Big Problems
When you think about corrugated boxes, you probably think about the paper quality, ply strength, or printing. But one of the most overlooked factors that directly impacts durability and customer satisfaction is the type of stitching pin used in the box.
In traditional box manufacturing, metallic stitching pins are used to hold the flaps securely together. However, these pins are highly prone to rusting when exposed to moisture — a common issue during humid weather, storage, or shipping.
Rusting may seem like a minor cosmetic problem, but in reality, it causes major losses in packaging appearance, product hygiene, and brand reputation. At ASPV Industries Pvt. Ltd., we’ve eliminated this issue completely by using copper stitching pins — designed to resist rust, extend box life, and maintain a clean, professional finish.
Why Rusting Happens in Corrugated Box Pins
Rusting is the result of a simple chemical reaction — iron + moisture + oxygen = rust (iron oxide).
Traditional box stitching pins are made of mild steel or galvanized metal, which oxidize quickly in humid or damp conditions. In corrugated manufacturing, moisture exposure occurs at multiple stages:
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During Manual Pasting:
Excess glue introduces water into the sheet, which transfers moisture to the pins during stitching. -
Ambient Humidity in Production Areas:
In regions like Delhi NCR, moisture levels rise sharply during monsoon months, leading to condensation and oxidation on metallic pins. -
Storage & Transportation:
Boxes stacked in warehouses or transported over long distances face fluctuating humidity levels. Even small traces of moisture inside packaging layers trigger rust formation. -
Moisture from Products Inside Boxes:
Boxes used for food, FMCG, or footwear often contain products with mild moisture or oils, accelerating rust formation at pin joints.
The Hidden Cost of Rusted Pins
Rusting is not just an aesthetic issue — it affects multiple aspects of the packaging lifecycle.
1. Damage to Product and Branding
When rusted pins stain the paper, the box looks old and unclean. For brands selling consumer goods, it creates a negative first impression. Rust marks can also transfer to the product inside, damaging clothing, shoes, or food packaging.
2. Reduced Box Durability
Corroded pins lose structural integrity over time, making the stitched joint weak. This leads to box deformation, open flaps, and potential product spillage during transport.
3. Increased Rejection Rates
Export clients and organized retail buyers often reject boxes showing rust marks or discolored edges, leading to direct financial losses for suppliers.
4. Shortened Shelf Life
Boxes with rusted pins degrade faster, especially in long-term storage or humid conditions. Even high-quality 5-ply cartons lose strength if the joints corrode.
Why Manual Stitching Makes It Worse
In manual stitching processes, operators often use low-cost mild steel pins and apply them to semi-dry boxes. Since these boxes retain internal moisture, corrosion starts almost immediately — sometimes even before dispatch.
Moreover, manual processes cannot control:
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Pin depth and alignment (causing uneven sealing)
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Pin density (too few pins weaken the joint)
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Handling conditions (touching with bare hands adds oil and salts, accelerating rusting)
As a result, boxes that look perfect on day one begin showing rust marks within days, especially in humid storage environments.
ASPV’s Solution: Copper Stitching Pins for Rust-Free, Long-Lasting Boxes
At ASPV Industries Pvt. Ltd., we go beyond conventional manufacturing to ensure that every component of your box — from flute to finish — performs reliably. One of our key quality measures is the use of copper stitching pins instead of traditional metal pins.
Here’s how our copper solution solves the rusting problem completely:
1. 100% Rust-Proof Composition
Copper doesn’t oxidize in the same way as iron. It forms a thin protective layer called patina, which prevents further corrosion. This means ASPV boxes stay rust-free even in the most humid conditions.
2. Hygienic and Clean Finish
Copper pins don’t leave brown stains or streaks on paper. The box surface remains clean, ensuring it’s suitable for food, pharmaceuticals, cosmetics, and premium retail packaging.
3. Enhanced Joint Strength
Copper pins have higher tensile strength and elasticity, ensuring tight joints without damaging the paper. They hold up better under pressure and vibration during shipping.
4. Compatible with Fast-Dry Boxes
Because ASPV’s boxes are produced using moisture-controlled corrugation and fast-dry adhesives, copper pins remain unaffected by any residual humidity in the sheet.
5. Longer Shelf Life
Boxes stitched with copper remain structurally sound for months, even in variable humidity — ideal for exporters and warehouses storing boxes in bulk.
6. Premium Visual Appeal
The copper stitching gives a distinct golden finish that complements high-quality printed boxes, making them look polished and professional.
Integrated with ASPV’s Complete Moisture-Control Process
ASPV doesn’t just add copper pins as a surface-level solution — it’s part of our integrated manufacturing philosophy.
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Our automated pasting and drying systems ensure sheets are moisture-balanced before reaching the stitching stage.
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3-ply and 5-ply boards are tested for proper adhesion and strength before pinning.
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Two-colour Flexo printing is performed only after boxes are completely dried and hardened.
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Copper stitching pins are used as the final reinforcement to guarantee durability and appearance.
This combination ensures a moisture-free, rust-free, ready-to-deliver box — every single time.
Real-World Example: A Food Exporter’s Rust Problem Solved
A client from the food packaging sector faced repeated complaints about rust marks appearing on their export cartons during sea shipments. The issue wasn’t with paper quality but with traditional iron stitching pins corroding due to marine humidity.
After switching to ASPV’s copper-pinned boxes, the results were immediate:
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Zero rust stains after 45 days of sea transit
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Improved joint strength even after stacking in humid conditions
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Better export presentation, as boxes retained their clean look on arrival
Today, the client exclusively sources all corrugated packaging from ASPV for both domestic and international markets.
Conclusion: It’s Time to Upgrade from Iron to Copper
A box’s durability depends on more than its paper quality — it depends on every detail, right down to the pins that hold it together. Rusted joints can silently destroy months of hard work, affecting both aesthetics and safety.
With ASPV’s copper-stitched, moisture-controlled corrugated boxes, you can guarantee that your packaging remains clean, strong, and rust-free, no matter the weather or storage duration.
When precision meets protection, your packaging doesn’t just perform better — it reflects excellence.
Choose ASPV. Choose strength that lasts.
📞 Contact ASPV Industries Pvt. Ltd.
Address: A-79, Mangolpuri Industrial Area Phase-II, New Delhi - 110086
Phone: 011-41528289, 9999821806
Website: www.aspvind.com
Email: info@aspvind.com
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