The frame is the edge steel section around the mesh; bent and welded frames differ markedly in forming, cost, and rigidity, directly affecting corner impact resistance. The frame is unassuming, but it is the key to keeping wires in and the cage from loosening.
Bent frames are formed from a single steel strip bent in one operation into a frame, with rounded corner transitions, few welds, flat appearance, and low internal stress—suitable for mass standard cages; but the bending die is fixed, and changing size requires a new die, raising cost for small batches or non-standard sizes.
Welded frames are made by cutting and welding several steel sections into a frame, with welded corners; they are highly flexible and can be made to any size, suitable for non-standard customization; the downside is many corner welds, and if post-weld grinding is inadequate, corners crack on impact.
Rigidity comparison: with equal materials, bent frames are more integral and torsion-resistant; welded frames rely on weld seams, making weld corners weak points. For heavy-duty cages with frequent forklift impacts, choose bent frames, or add corner gusset welds to welded frames. Bent-frame rounded transitions also avoid hand cuts and cloth snags.
Selection advice: for standard sizes and high-volume products choose bent frames—fast lead time and stable price; for non-standard sizes or special loads choose welded frames and require full corner welding plus gussets. When requesting a quote, ask the manufacturer to state whether the frame is bent or welded—both price and rigidity differ. Tongnuo does both processes and recommends by batch size.