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Senior forge-welded gratings are made by high-power electric resistance welding machine. Steel gratings are constructed of bearing bars in longitudinal direction and cross bars in transverse direction. The cross bars which lined up in certain spacing are pressed into the upper edges of bearing bars standing up side by side; The machine electro-forges them into grating panel with strong welds and rectangular openings surface.

According to the upper edges of bearing bars, Senior gratings can be classified Into three types,namely, plain style, serrated type, and I type, Plain type steel gratings are most commonly used;With perfect anti-skid performance, serrated type steel gratings are mainly used for operate platform with oil pollution and walkway with slope. Featured by material saving under the same load, attractive appearnce, and high price, I type steel gratings are mainly used for export contracts. On the basis of the sizes and pitches of bearing bars and the pitches of cross bars, Senior steel gratings can form more than 300 varieties, may be made surface-protective treatment in light of different using environments.