There are two methods for manufacturing grating panels: machine pressure welding and manual fabrication.
Machine pressure welding utilizes a high-pressure resistance welding machine. A robotic arm automatically places crossbars across evenly spaced flat steel bars; high welding power and hydraulic pressure then press-weld the crossbars into the flat bars, resulting in high-quality steel grating with strong weld points and exceptional stability and strength. This process is influenced by equipment specifications and the matching of current and voltage; generally, welding two crossbars yields higher strength than welding a single one. The process also depends on the dimensions of the raw flat steel; significant width variations in the flat steel can affect weld strength and lead to inconsistency. Potential defects include "false welds" (incomplete fusion) and "weak welds" (poor bonding), which can cause the crossbars to detach. Due to equipment capacity limitations, this process cannot produce heavy-duty grating with large cross-sections. Typically, equipment with a rated capacity below 800 kVA is limited to producing grating with flat bars up to 4 mm thick, while 1250 kVA equipment can handle thicknesses of 5–6 mm.
Manual fabrication methods include press-locking, welding, and interlocking (weld-free) assembly. For manually welded grating, holes or notches are first punched into the flat bars; crossbars are then inserted and spot-welded in place. While small gaps may exist between the crossbars and flat bars, every contact point is welded (or, for closely spaced crossbars, alternating points may be welded). This production method offers flexibility and product diversity, enabling the manufacture of a full range of grating types-with particular advantages in heavy-duty applications. However, because welding is performed entirely by hand, there is a risk of insecure welds, missed welds, or false welds, all of which can compromise structural strength.
