The door frame determines from which side materials are picked and whether you can reach in without moving the cage; common types are double doors, flip-up doors, and side-opening doors. Choosing the right door type makes a real difference in picking efficiency; choosing wrong means dragging the whole cage out to rummage.
Double doors consist of two hinged leaves left and right, joined in the middle by a latch or lock; when opened, the front is fully open, suitable for front picking and line-side replenishment of material carts—the most versatile type. The downside is that opening requires about half a door width of space in front, making it hard to open when cages are placed tightly. Large door faces should have vertical stiffeners to prevent sagging after long-term opening and closing.
Flip-up doors hinge at the top and flip upward, taking no front floor space when open, suitable for warehouses where cages sit tight against racks or side-by-side. However, on tall cages the door panel's center of gravity rises when flipped up, and closing it takes force; heavy doors are recommended to have gas spring assistance.
Side-opening doors open along one long side as a full panel, suitable for long bars, shafts, and tubes picked from the side; they also make it easy to keep the cage fixed on a rack and open only the door to replenish. Side doors are structurally complex and slightly more expensive, and because the hinges undergo long-term torsion, choose reinforced hinges.
Selection points: frequent front picking at line side chooses double doors; tight placement with infrequent opening chooses flip-up doors; long materials choose side doors. Nanjing Tongnuo Warehouse Equipment Manufacturing Co., Ltd. supports mixing the three door types and customizes by workstation flow to avoid door-opening interference.