Welded platform gratings are made from parallel bearing flat bars that are joined transversally by grooved rounded bars in such a way that those elements create one surface at the top of the grating.
Fig. 2. Standard grating
Serrated grating (SERR)
In case of a serrated grating, bearing flat bars with trapezoidal cuttings are used (Fig.4). It is a grating with a higher nonslip level and this is why it is often used in particularly dangerous places, such as sloppy walkways, greasy floors and so forth.
Fig. 3 Serrated grating
Fig 4. Serration parameters
Security Mesh (SM) grating
A Security Mesh grating may be produced on the basis of a standard or a serrated grating by welding a flat bar of a thickness g=0.5mm and with openings 8mmx8mm at the bottom of the grating, between the bearing flat bars
Fig.5. Standard SM grating
Fig. 6. Serrated SM grating
Fig. 7. Diagram of a Security Mesh flat bar
Grating type WBB can be made on the basis of a standard or a serrated grating by welding a grooved bar 4.8mm in diameter at the bottom of it, between bearing flat bars.
Fig. 8. Standard WBB grating
Fig. 9. Serrated WBB grating
Special shapes (burnt – out) gratings
Burnt – out gratings are gratings of various shapes manufactured on a basis of a technical drawing. In case of burnt – out gratings (but not exclusively), it is possible to use the “sideboard” framing.
The sideboard may be made of a material of a thickness which not exceeding g=5 mm.
Fig. 10. Grating with arc and straight lines
When calculating parameters L and B, the smallest rectangular in which the given grate could be written in should be chosen, as shown in Figure 11.
Fig. 11. Dimensioning of special shape grating
Gratings of special dimensions (XX and YY)
Grating type XX is characterised by symmetry towards parameter B. If the width of the grating is other than it should result from the size of the mesh, the extreme mesh ends size are the same, but not equal to 34,3 mm, Grating type YY is characterised by symmetry towards parameter L. The ends of bearing bars (or of the frame) are all at the same distance from the closest transverse bar.
Fig. 12. Diagram of a XX and YY grating
Stainless steel gratings
Thanks to its modern production lines, the TERMETAL Group also produces stainless steel gratings of the INOX 304 or INOX 316 type.
In case of stainless steel gratings, a rounded flat bar is used with a diameter Ø= 5 mm.
Production programme based on the graduation
Table 1. Grating production programme
Worth knowing: Tolerances for such widths +/- 3 mm.
Table 2. Recommended grating widths for B#i000