Planning and design, floor gratings

GRATINGS, PLANNING AND DESIGN

Our drawing office is at your service for questions on the dimensioning, drawing and design of floor gratings.


Geometry

The grating's component parts are load bearing bar, cross bar and edge bar.
During all planning involving pressure welded grating, you should as far as possible adapt the layout to the grating's standard width (1000 mm) to obtain the most economical alternative.

If the grating is to be laid across several supports, it is best to choose grating in larger sizes. This gives a more beautiful pattern with fewer joints.

To prevent incorrect placement of the load bearing rod (the grating's bearing structure), avoid grating with square dimensions.


Mesh widths

We have a wide range of different mesh sizes for grating. For the mesh width, these sizes are specified c/c. The first dimension is always c/c load bearing bar and the second dimension is always c/c cross bar.

Name Mesh width c/c
AxB (mm)
Load bearing bar thickness T (mm) Load bearing bar heights
C (mm)
B9 12 x 100 3 20, 25, 30, 35, 40
N4 17 x 50 2 20, 25, 30, 35, 40
N4 17 x 50 3 20, 25, 30, 35
N6 17 x 75 2 20, 25, 30
N9 16 x 100 3 20, 25, 30, 35, 40, 45, 50
D4 22 x 50 3 20, 25, 30, 35, 40, 45, 50
D4 22 x 50 4 30, 35, 40, 45, 50, 60
D4 22 x 50 5 20, 25, 30, 35, 40, 45, 50, 60
D6 22 x 75 2 25
D6 22 x 75 3 20
F4 25 x 50 3 20, 25, 30, 35, 40, 45, 50
F4 25 x 50 4 30, 35, 40, 45, 50, 60, 70, 80
F4 25 x 50 5 20, 25, 30, 35, 40, 45, 50, 60, 70, 80
H3 33 x 37 2 20, 25, 30, 35, 40
H3 33 x 37 3 20, 25, 30, 35, 40 45, 50
H3 33 x 37 4 30, 35, 40 45, 50, 60, 70, 80
H3 33 x 37 5 20, 25, 30, 35, 40 45, 50, 60, 70, 80
H4 33 x 50 2 20, 25, 30, 35, 40
H4 33 x 50 3 20, 25, 30, 35, 40, 45, 50
H4 33 x 50 4 30, 35, 40, 45, 50, 60, 70, 80
H4 33 x 50 5 20, 25, 30, 35, 40, 45, 50, 60, 70, 80
H6 33 x 75 2 25, 30, 40
H6 33 x 75 3 20, 25, 30, 35, 40, 45, 50
H9 33 x 100 3 20, 25, 30, 35, 40, 45, 50
H9 33 x 100 4 30, 35, 40, 45, 50
H9 33 x 100 5 20, 25, 30, 35, 40, 45, 50, 60
J9 41 x 100 3 20, 25, 30, 35
J9 41 x 100 4 30, 35, 40, 45, 50, 60
J9 41 x 100 5 20, 25, 30, 35, 40, 45, 50, 60
I6 66 x 75 3 20, 25, 30
I4 68 x 50 2 20
I9 100 x 100 3 20, 25, 30
Name Mesh width c/c
AxB (mm)
Load bearing bar thickness T (mm) Load bearing bar heights
C (mm)
N9-T 16 x 100 3 25, 30, 35, 40
H4-T 33 x 50 2 25
H4-T 33 x 50 3 25, 30, 35, 40, 45, 50
H4-T 33 x 50 4 30, 35, 40, 45, 50, 60, 80
H4-T 33 x 50 5 25, 30, 35, 40, 45, 50, 60
F4-T 25 x 50 3 25, 30, 35, 40, 45, 50
F4-T 25 x 50 4 30, 35, 40, 45, 50, 60
F4-T 25 x 50 5 25, 30, 35, 40, 45, 50, 60
H9-T 33 x 100 3 25, 30, 35, 40, 45, 50
H9-T 33 x 100 4 30, 35, 40, 45, 50
H9-T 33 x 100 5 25, 30, 35, 40, 45, 50, 60
J9-T 41 x 100 3 25, 30, 35, 40, 45, 50
J9-T 41 x 100 4 30, 35, 40, 45, 50, 60
J9-T 41 x 100 5 20, 25, 30, 35, 40, 45, 50, 60
HN9-T 35 x 100 3 25, 30, 35, 40, 45, 50
HN9-T 35 x 100 4 25, 30, 35, 40, 45, 50
JN9-T 41 x 100 3 25, 30, 35, 40
JN9-T 41 x 100 5 25, 30, 35, 40, 45, 50, 60
Name Mesh width c/c
AxB (mm)
Load bearing bar thickness T (mm) Load bearing bar heights
C (mm)
A22x22 22 x 22 2 20, 25, 30, 40, 50
A33x11 33 x 11 2 20, 25, 30, 40, 50

Construction dimensions with whole mesh widths

In the table, the construction dimensions in which the grating can be obtained (with full mesh) are set out.

Marked dimensions specify standard widths.

H also
for SS.
c/c 33
(mm)
H also
for SS.
c/c 34
(mm)
F

c/c 25
(mm)
D

c/c 22
(mm)
N

c/c 16
(mm)
N

c/c 17
(mm)
B

c/c 12
(mm)
I4 20/2

c/c 68
(mm)
J

c/c 41
(mm)
JN9-T

c/c 41
(mm)
HN9-T

c/c 35
(mm)
1000 1000 1000 1000 1000 1000 700 969 1000 1000 1000
966 962 973 972 982 983 685 898 957 955 961
933 927 949 950 966 965 672 830 914 915 926
900 893 923 928 >949 949 659 761 872 874 890
867 858 898 906 933 931 646 692 830 832 855
834 825 873 884 916 914 633 624 788 791 820
801 790 849 862 900 897 620 554 745 750 785
768 756 825 840 883 880 608 487 700 709 750
734 722 799 818 867 862 596 420 662 668 714
700 687 774 797 850 845 584 350 621 626 679
668 653 750 775 834 827 571 282 580 585 644
635 618 725 753 817 811 559 213 540 544 608
602 584 700 731 801 793 547 143 500 503 573
568 551 674 709 784 776 535 75 456 462 538
534 516 650 687 768 759 522 416 421 503
500 485 625 665 751

742

511 375 380 467
469 451 600 643 734 724 500 334 338 432
436 417 575 621 718 707 485 293 297 397
403 383 550 599 700 690 473 252 256 362
370 348 526 577 683 673 460 211 215 326
337 314 500 555 665 656 448 171 174 291
304 280 475 533 649 639 436 130 132 256
271 246 451 511 632 622 424 89 91 221
238 211 426 490 616 605 411 48 50 185
205 178 401 468 600 587 399 150
171 144 377 446 583 570 387 115
139 109 352 424 568 553 374 80
106 75 327 402 550 536 362 44
73 40 302 380

534

519 350
40 278 358 518 502 338
253 336 500 486 326
228 314 483 469 313
204 292 465 452 301
179 270 449 435 289
154 248 433 418 276
130 226 416 400 264
105 204 400 383 252
81 182 383 366 240
56 160 367 349 228
32 139 351 332 215
117 334 315 203
95 318 298 191
73 302 280 178
51 285 262 166
29 269 246 154
252 229 142
236 212 130

220 195 117
203 178 105

187 160 93
171 143 80

154 126 68
137 109 56
122 92 44
105 74 31
89 57 19

72 40
56 23
40

Opening area

By opening area, we mean the free dimension in the grating. A piece of information that often comes up in discussions about the transmission of light.

Name Mesh width Load bearing steel dim. Cross bar steel dim. Opening area %
B9 12 x 100 3 6.5 68.9
N4 17 x 50 2 5 77.8
N4 17 x 50 3 6.5 68.7
N6 17 x 75 2 4 82.6
N9 16 x 100 3 5 77.3
D4 22 x 50 3 6.5 73.2
D4 22 x 50 4 6.5 68.6
D4 22 x 50 5 6.5 64.0
F4 25 x 50 3 6.5 74.7
F4 25 x 50 4 6.5 70.6
F4 25 x 50 5 6.5 66.5
H3 34 x 37 2 4 83.2
H3 34 x 37 3 4 80.2
H3 33 x 37 4 6.5 70.1
H3 33 x 37 5 6.5 67.0
H4 33 x 50 2 5 83.8
H4

33 x 50

3 5 80.7
H4 33 x 50 4 6.5 74.6
H4 33 x 50 5 6.5 71.5
H6 34 x 75 2 4 88.4
H6 33 x 75 3 5 83.7
H9 33 x 100 3 6.5 84.2
H9 33 x 100 4 6.5 81.1
H9 33 x 100 5 6.5 78.0
J9 41 x 100 3 6.5 86.0
J9 41 x 100 4 6.5 83.5
J9 41 x 100 5 6.5 81.0
I6 66 x 75 3 5 88.2
I9 100 x 100 3 6.5 90.2
Name Mesh width Load bearing steel dim. Cross bar steel dim. Opening area %
N9-T 16 x 100 3 5 77.3
H4-T 33 x 50 2 5 83.8
H4-T 33 x 50 3 5 80.7
H4-T 33 x 50 4 6.5 74.6
H4-T 33 x 50 5 6.5 71.5
F4-T 25 x 50 3 6.5 74.7
F4-T 25 x 50 4 6.5 70.6
F4-T 25 x 50 5 6.5 66.5
H9-T 33 x 100 3 6.5 84.2
H9-T 33 x 100 4 6.5 81.1
H9-T 33 x 100 5 6.5 78.0
J9-T 41 x 100 3 6.5 86.0
J9-T 41 x 100 4 6.5 83.5
J9-T 41 x 100 5 6.5 81.0
HN9-T 35 x 100 3 6.5 70.8
HN9-T 35 x 100 5 6.5 65.0
JN9-T 41 x 100 3 6.5 69.2
JN9-T 41 x 100 5 6.5 64.2
Name Mesh width Load bearing steel dim. Cross bar steel dim. Opening area %
A22x22 22 x 22 2 2 82.0
A33x11 33 x 11 2 2 76.0

Tolerances, Dimensions

Length, width & diagonal dimensions

Our production is based on fixed tolerances for the length, width and diagonal dimensions. The tolerance is set to +0 / -4 mm.

Max. length of cross bar ends

Cross bar ends have a maximum protrusion of 2 mm.

 

Load bearing bar deflection

During the manufacture of grating, the product naturally becomes convex. The maximum load bearing bar deflection is 1/200 of the span.

Cross bar division

Our production is based on fixed tolerance for the cross bar division. The placing of the cross bars follows the specified mesh width with tolerances according to the diagram.


Fixing

For fixing gratings, we off a number of different fixings. Both complete clamps consisting of top section, bottom section, bolt and nut or, alternatively, top section and fixing screw. For gratings trafficked by heavy vehicles, we also offer mounting lugs welded to the bottom of the grating's mesh.


Marking

Each grating can be provided with a substantial identification tab with clear characters that refer to the layout drawing, which makes the assembly work easier. Frequently used for slightly larger projects.


Surface treatment

Hot dip galvanisation

The diagram shows the average service life for different thicknesses of zinc in different environments.

Treatment of stainless steel

Stainless steel grating is pickled to attain a good surface finish.

Treatment of aluminium

Aluminium grating is pickled to attain a good surface finish.


Film Z-profile kerb angle frames assembly


Load tables

Assumptions for load tables
Calculations according to Eurocode are performed with a calculation program. (NSAB)
Partial coefficient for load = 1.5
Table values indicate characteristic loads for safety class 2
For safety class 1: multiply the value by 1.1
For safety class 3: multiply the value by 0.91

To consider!
When dimensioning chequer plate for pedestrian traffic, you should calculate using a distributed load of 5 kN, even if the design load for the supporting structure is lower.

Material grade
Load bearing bar 2-3 mm: Fyk = 235 N/mm²
Load bearing bar 4-5 mm: Fyk = 355 N/mm²

Cross bar d=4-6.5 mm: Fyk = 235 N/mm²


Documentation

Load table Grating & vehicular grating