There are multiple challenges in manufacturing this type of box:
PP hollow sheet features high plastic resilience, which causes the folded box to spring open easily. The smooth panel surface leads to slipping during feeding and double-sheet picking. Minor misalignment of square panels will result in rhombus-shaped finished boxes. In addition, the low box height leaves limited operating space for mechanisms, often causing incomplete locking of box tabs.
To solve these issues, we implemented targeted upgrades to the original machine:
◆ Enlarged material warehouse with adjustable multi-point suction cups to eliminate edge warping and double-sheet picking for large panels
◆ Added segmented pre-folding and pressure-holding structure. Instead of rigid compression forming, this counteracts plastic springback to keep boxes intact after folding
◆ Widened forming station with bidirectional positioning mechanism, specially designed for square boxes to prevent shifting and deformation
◆ Optimized folding blade structure for low-profile boxes with extended stroke adjustment, enabling easier format changeover for multiple box sizes
The modified machine can operate as a standalone unit or integrate with a full automated production line.
Actual production capacity reaches 400–600 boxes per hour. It eliminates manual folding and enables stable automated manufacturing.
Tip: Crease quality of raw PP hollow sheet is critical. Incoming material condition directly affects the finished product yield.