Post on 24-Jan-2022
Designing Aid for Walkway Gratings
NAGÉV RÁCS Kft.
Walkway grating, stair, step, drainage, scraper grating, ventilation well cover, screen grid
NAGÉV
Tartalomjegyzék
1. INTRODUCTION ......................................................................................................................6
2. DEFINITIONS ..........................................................................................................................7
2.1. THE WALKWAY GRATING .........................................................................................................7
2.2. BEARING BAR ..........................................................................................................................7
2.3. CROSSBAR ..............................................................................................................................7
2.4. FRAME ELEMENT ....................................................................................................................7
2.5. BAR SPACING ..........................................................................................................................8
2.6. TREAD SURFACE .....................................................................................................................8
2.7. SURFACE PROTECTION ...........................................................................................................8
2.8. DIMENSION .............................................................................................................................9
2.9. SHAPE .....................................................................................................................................9
2.10. ILLUMINATION DIMENSION .....................................................................................................9
3. THE TYPES OF GRATINGS ....................................................................................................10
3.1. PRESS GRATING (SIGN: P) ...................................................................................................10
3.2. INTERLACED GRATING (SING: FZ) ........................................................................................10
3.3. WELDED PRESS GRATING (SIGN: SP) ..................................................................................11
4. INFORMATION REQUIRED FOR DESIGNING .......................................................................11
4.1. SELECTION, DIMENSIONING OF THE WALKWAY GRATING ...................................................11
4.2. LOADING MODELS ................................................................................................................13
4.3. OTHER DESIGNING HINTS ....................................................................................................16
4.4. FITTINGS OF THE WALKWAY GRATINGS ...............................................................................18
4.5. FASTENING OF THE WALKWAY GRATINGS ............................................................................20
5. THE DIMENSIONAL- AND GEOMETRICAL TOLERANCES OF THE WALKWAY GRATINGS ..223
Designing Aid
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5.1. LENGTH TOLERANCES OF BEARING BAR- (H) AND CROSSBAR (L) DIRECTION .................22
5.2. THE LENGTH DIFFERENCE OF THE DIAGONALS ...................................................................22
5.3. TOLERANCES OF THE CUTOUTS ..........................................................................................23
5.4. TOLERANCES OF SHAPE INACCURACIES .............................................................................23
5.5. SKEWNESS OF THE BEARING BAR, SKEW END-CUTTING ....................................................24
5.6. THE PROTRUSION OF THE CROSSBAR .................................................................................24
5.7. THE OVERHANG OF THE FRAME ELEMENT ...........................................................................24
5.8. THE OVERHANG OF THE CROSSBAR ON THE OUTERMOST BEARING BAR OR THE FRAME ELEMENT ...............................................................................................................................24
5.9. THE TORSION OF THE WALKWAY GRATING ..........................................................................24
6. PRODUCTS ...........................................................................................................................25
6.1. INDUSTRIAL WALKWAY GRATING ..........................................................................................25
6.2. STAIR GRATING .....................................................................................................................25
6.3. BOARD GRATING ...................................................................................................................26
6.4. DRAINAGE SYSTEMS .............................................................................................................27
6.5. SCRAPER GRATING ...............................................................................................................28
6.6. VENTILATION WELL GRATING ...............................................................................................28
6.7. SCREENING GRID .................................................................................................................28
6.8. TREE FOOT GRATING ............................................................................................................29
6.9. STAIRCASE STRUCTURES .....................................................................................................29
6.10. SHELF GRATINGS ..................................................................................................................32
6.11. L-STEEL FRAMED GRATINGS .................................................................................................33
7. SURFACE PROTECTION .......................................................................................................34
7.1. HOT-DIP GALVANIZING ..........................................................................................................34
7.2. PAINTING ...............................................................................................................................35
7.3. DUPLEX PROTECTION ...........................................................................................................35
8. PRICING ................................................................................................................................35
9. INQUIRY, ORDER ..................................................................................................................36
10. RELATED SERVICES .............................................................................................................37
10.1. CONSULTATION .....................................................................................................................37
10.2. ON-SITE SURVEY ...................................................................................................................37
10.3. DESIGNING ...........................................................................................................................37
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10.4. THE MANUFACTURE OF OTHER STRUCTURES .....................................................................37
10.5. DELIVERY ...............................................................................................................................37
10.6. ASSEMBLY .............................................................................................................................37
10.7. STOCKS .................................................................................................................................37
11. CERTIFICATIONS ..................................................................................................................38
Designing Aid
6
1. IntroductionThe name NAGÉV has now been well known among users of industrial walkway grating. The group, which has evolved from a 25 m2 plant, is an industrial enterprise having more than thirty years of his-tory. NAGÉV Ltd. was founded by Antal János Nagy in 1991 primarily as a private enterprise specialized in the manufacture of walkway gratings, with 100 percent sole ownership.
Since the beginning of its operation the company has been playing a signifi cant role among domestic producers of walkway grating. The products of the company are available all around the country; many of them are installed for major investment projects. They are perfectly suitable for bridging a particular span, as well as for bearing passenger and freight traffi c. The products are universal; they are linked not only to one industrial sector. The walkway gratings of NAGÉV RÁCS Ltd. are ideal for covering walk-ing surfaces of industrial plants, power plants, public utilities, bridges, stairs, work platforms, opera-tor’s platforms and footbridges of scaffold systems, as well as for making them securely passable.
In addition to domestic customers the NAGÉV type walkway grating is well-known, recognized and de-manded by foreign companies as well. In addition to industrial scale orders the manufacture of scraper grids for public use and rainwater trench drains used in front of garages represent a signifi cant volume.
The company’s activities, from its foundation to the present day, are characterized by the trinity of high quality, reasonable price and the strict compliance with the delivery dates. The products are own developments, and some of them are based on our own patent.
The NAGEV group includes Hungary’s most modern and Eastern Hungary’s largest hot-dip galvanizing plant. The factory in the city of Ócsa was opened in 2011, while the plant in Tiszacsege city has been operating successfully since 1998. With the completion of the high-tech facility in Ócsa an opportunity arose to galvanize industrial size steel structures in our country too.
The NAGÉV group is one of the market leaders in our country both in the walkway grating and the hot-dip galvanizing business sector.
With this brochure we would like to introduce the products of NAGÉV RÁCS Ltd. which belongs to NA-GÉV Group, helping you in your design and construction work.
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2. Defi nitions
2.1. The walkway grating
The walkway grating is a framed fl at surface structure, established between two supports, composed of bearing bars and cross bars, po-sitioned perpendicularly on one another, which is capable of bearing the load imposed on it (Fig. 1.)
Fig. 1. Structural design DIN 24537
2.2. Bearing bar
The bearing bar is the load-bearing element located perpendicularly to the supporting side, i.e. the contact side, which is prepared with the cross section selected on the basis of the support distance and load demand. Its height ranges from 20 mm to 150 mm; its thickness is between 2 mm and 10 mm.
2.3. Crossbar
It is the element running parallel to the support side, located perpendicularly to the bearing bars, the element holding them together through slots. Its main tasks are to prevent defl ection of the bearing bars, develop the tread, as well as to evenly distribute load on the entire surface of the grating. The height of the crossbar ranges from 8 mm to 50 mm, its thickness is between 2 mm and 10 mm. The determination of the cross-section of the crossbars depends on the production technology.
2.4. Frame element
This is the element that closes the bar-ends of the grating, increases its strength and load carrying capacity, and gives the grating an aesthetic contour. The frame elements of the gratings are prepared from the profi le that has the same cross section as that of the bearing bars. The overall dimensions of the grating are determined by the external dimensions of the frame element.
Frame element
Cross bar
Bearing bar
Support
Designing Aid
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2.5. Bar spacing
An ordered pair of numbers that defi nes the axial distance between the bearing bars and the crossbars, the sum of which is 11 mm or integral multiple of 11 mm. The fi rst number represents the spacing of bearing bars (sym-bol: t1), the second number indicates the spacing of cross bars (symbol: t2). For exam-ple: 33 / 33; 22 / 22 ; 33 / 66; 44 / 22 (Fig. 2.)
Fig. 2. Bar spacing
2.6. Tread surface
The surface of the walkway grating, where the upper edges of the bearing- and crossbars form a plane, is called the tread surface. Normally walkway gratings are constructed with fl at tread surface, but on request – for improved grip of the surface – the bearing and cross bars are made slip-proof. The symbol for slip-proof tread surface is CSM. Countersunk patterns, i.e. those produced by cutting out (CSM2), as well as patterns emergent from the tread (raised) (CSM4) are distinguished.
Fig.3: CSM2 tread Fig. 4: CSM4 tread
2.7. Surface protection
The most general and most reliable corrosion protection process of the walkway gratings made from carbon steel is hot-dip galvanizing, during which the surface of the products is supplied with an excel-lently corrosion-resistant metal coat, compared with other surface protection processes, having better mechanical properties. NAGÉV RÁCS Kft. sells its products primarily in a hot-dip galvanized design.On demand, the walkway grating is also sold with an electrostatically powder-coated plastic coat in colours as per the RAL colour chart.The application of the so-called duplex coat combining the advantages of the zinc and plastic protec-tive layer is recommended against the strong corrosion effects. In case of this technology the surface of the products hot-dip galvanized in our company is supplied with a plastic coat. In case of individual demands our walkway gratings are also sold in a natural design, i.e. without any coat. Our grating prod-ucts made from a corrosion- and acid-resistant base material with stained surface are recommended.
t1
H – B
earin
g-bar
way
dim
ensio
nL – Cross-bar way dimension
t2
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2.8. Dimension
It determines the overall, i.e. width and length dimensions of the walkway grating. The fi rst dimension fi gure indicates the size parallel with the direction of the bearing bar (sign: H), the second one indi-cates the size parallel with the direction of the crossbar (sign: L) (Fig. 5). In case of profi le (not rect-angular) gratings the overall dimensions (H x L) are meant as the dimension of the grating (Fig. 6).
Fig. 5: The dimensions of the grating Fig. 6: Dimension specifi cation of the profi le gratings
2.9. Shape
The concept determining the geometry of the walkway grating. The profi le is infl u-encing the price and produc-tion technology of the prod-uct. Each grating is classifi ed into any of the following shape groups (Fig. 7) when pricing.
Fig. 7: Shape groups
2.10. Illumination dimension
The walkway grating means the size of the slot arising from the thickness dimensions of the bearing- and crossbars, as well as that arising from their spacing. For exam-ple, in case of a grating with a 3 mm thick bearing bar and 2 mm thick crossbars, with 33/66 bar spacing, the illumination dimen-sion is 30 x 64 mm (Fig. 8).
Fig. 8: Light dimension
Light dimension
L – dimension of crossbar direction
H – dimension of b
earing
bar direc
tion
L
H
NORMALRectangular or square gratings. Designation: NORMAL
SIMPLE SQUARE-CUTMaximum 2 pc square-cut/grating. Designation: SQUARE-CUT E
COMPLEX SQUARE- CUTMore than 2 pc square-cut/grating. Designation: SQUARE-CUT B
SIMPLE PROFILEStraight-sided, maximum pentagon, but at least 2pc angles are 90°. Designation: PROFILE E
COMPLICATED PROFILEOther profi le-arched, polygon. Designation: PROFILE B
SIMPLE BREAKTHROUGH1 pc circle or rectangular shaped breakthrough parallel with the bar direction. Designation: BREAKTHROUGH E
COMPLEX BREAKTHROUGHOther breakthrough. Designation: BREAKTHROUGH B
STAIR, LANDINGWith BB-edge (i.e. safety leading edge) and access side plate. Designation: STAIR
Designing Aid
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3. The Types of Gratings
3.1. Press grating (sign: P)
Cold bent U-steel or fl at steel framed steel structure made from steel sheet, consisting of bearing- and crossbars machined to size, pressed together at the interconnection points of the bearing- and crossbars in a square- or rectangular grid form. The press grating offers low prices and short manufacturing deadline due to the automated production. Besides the low net weight it has high load-bearing capac-ity and aesthetic appearance (Fig. 9).
Fig. 9: Pressed walkway grating with solid joints
Upon designing the product it has to be kept in mind that the dimensions of the grating of the bearing- and crossbar direction should not exceed 2,000 mm, if possible. The gratings of larger crossbar dimen-sion - since the grating has no loading capacity in the direction of the crossbars (!) – have to be di-vided. In a given case the manufacture of gratings with larger surface than usual can also be resolved, however, their planning is not recommended due to the diffi culties of production technology, transport and installation.
The most important features of the P grating- low price- lightweight design- high load-bearing capacity- variable bar spacing- waste-free production- aesthetic appearance- automated production- short manufacturing deadline
3.2. Interlaced grating (sing: FZ)
The interlaced grating of NAGÉV type is differ-ent in comparison with the press grating in re-spect that the bearing- and crossbars are inter-laced at their slots with form-locking joints and fastened by welding. This group includes the walkway gratings of relatively large bearing bar cross-section, which cannot be produced by pressing (Fig. 10). Fig. 10: Interlaced walkway grating with form-locking joints
A special product of NAGÉV RÁCS Kft. is the screen grid made from bearing- and crossbars of the same cross-section, as well as the unique, so-called “heavy grating” of high load-bearing capacity, which is also produced by interlacing.
Crossbar
Slit crossbar
A
A section
Bearing bar
Frame element
A section
A
Frame elementBearing bar
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The most important features of the FZ grating- form-locking joint at the connection points- CO2 shielded arc spot-welded connection between the grating elements- wide size range- the possibility to apply bearing- and crossbars of the same cross-section- individual bearing- and crossbar sections
3.3. Welded press grating (sign: SP)
It is a walkway grating produced by pressing resistance welding, where the bearing bars are made from fl at steel, the crossbars are made from twisted square steel, which thereby form a skid-proof surface. The SP gratings are cut to size from 6100x1000 mm sheet and framed (Fig. 11).
The most important features of the SP grating- specifi c sheet dimension is 6100 x 1000 mm- standard bar spacing- special skid-proof tread surface- onsite shaping possibility arising from the sheet size and pressing. (The subsequent cutting to size is recommended only in case of a natural design, i.e. without hot-dip galvanizing.)
Fig. 11: The SP grating
4. Information Required for Designing
4.1. Selection, dimensioning of the walkway grating
To select the appropriate walkway grating its intended use, the quality of the base material, as well as the most typical loading type have to be examined.
4.1.1. The intended use of the walkway gratings
Upon selection of the type of the grating the circumstances of installation of the grating (e.g. stair, drain grid, door mat, food industrial application, the effect of chemicals, vehicle traffi c, the cover of steel platforms of large size) have to be clarifi ed. The correct selection greatly reduces the faults aris-ing during designing, installation and use of the walkway gratings.
Frame element
Bearing barCrossbar:5 mm twined
Designing Aid
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4.1.2. Applied base materials
The walkway gratings can be made from hot or cold rolled, unalloyed structural, as well as corrosion-resistant steel (Table 1). We can undertake the manufacture of the walkway gratings made from a dif-ferent base material only in case of a demand for large quantity.
Table 1: The qualities of base materials
4.1.3. Strength dimensioning
Upon dimensioning of the walkway gratings the basic case of the two-support beam is used. During the calculation the bearing bar is considered as the load-bearing element, the cross-sectional size of which is meant as the type of the grating. The appropriate model is selected for the known load type, and the support distance is determined from the geometry of the steel structure. By knowing the size of the load, as well as the support distance, the type of the walkway grating can be easily determined from the table related to the loading model. The loading capacity of the walkway gratings complies with the DIN 24537 standard.
The loading table may be used to determine the following features:
Table 2: Loading features
Upon determining the values included in our loading tables the following strength features were used:
Flexibility modulus E=21 [daN/mm2]Maximum Allowable bending stress σ h meg=16 [daN/mm2] (daN: dekanewton)Dynamic factor μ=1,3The number of the bearing bars n=The number of the bearing bars located under the transmitting the load specifi c surface + 2 pcs
The bearing capacity of the walkway gratings made from acid- and corrosion-resistant steel (WNR 1.4301) is nearly the same as the values included in the tables.
Material number (WNR) EN 10 025 DIN 2393-2 MSZ 500 Description
1.0038 S235JR ST37-2 A38Unalloyed structural steel for
general purposesRm 380 N / mm2
Material number (WNR) EN 10 217 DIN 17455 MSZ 4360 Description
1.4301 X5CrNi18-20 X5CrNi18 10 KO 33 Acid- and corrosion-resistant austenite chrome-nickel steell
Serial number Known data 1 Known data 2 Wanted value
1 Grating type Distance between two supports Load-bearing capacity
2 Grating type Load-bearing capacity Distance between two supports
3 Load-bearing capacity Distance between two supports Grating type
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4.2. Loading models
4.2.1. Concentrated loading model
Concentrated load occurs when the walkway grating is loaded on a 200x200 mm surface. It cor-responds to the load generated by a pedestrian.
Table 3: Loading capacity of the walkway gratings for concentrated force in case of 33 mm spacing of the bearing bars
Rác
stíp
usF
[daN
] (~
kg)
H (
mm
)
f (m
m)
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
20 x
2F
683
341
228
171
137
114
9885
7668
6257
5349
4643
4038
36f
0,51
0,86
1,35
1,98
2,74
3,63
4,64
5,79
7,05
8,45
9,97
11,6
213
,40
15,3
117
,34
19,5
021
,78
24,1
926
,73
20 x
3F
1 02
451
234
125
620
517
114
612
811
410
293
8579
7368
6460
5754
f0,
510,
861,
351,
982,
743,
634,
645,
797,
058,
459,
9711
,62
13,4
015
,31
17,3
419
,50
21,7
824
,19
26,7
3
25 x
2F
1 06
753
335
626
721
317
815
213
311
910
797
8982
7671
6763
5956
f0,
410,
691,
081,
592,
192,
903,
724,
635,
646,
767,
989,
3010
,72
12,2
413
,87
15,6
017
,43
19,3
621
,39
25 x
3F
1 60
080
053
340
032
026
722
920
017
816
014
513
312
311
410
710
094
8984
f0,
410,
691,
081,
592,
192,
903,
724,
635,
646,
767,
989,
3010
,72
12,2
413
,87
15,6
017
,43
19,3
621
,39
30 x
2F
1 53
676
851
238
430
725
621
919
217
115
414
012
811
811
010
296
9085
81f
0,34
0,57
0,90
1,32
1,83
2,42
3,10
3,86
4,70
5,63
6,65
7,75
8,93
10,2
011
,56
13,0
014
,52
16,1
317
,82
30 x
3F
2 30
41
152
768
576
461
384
329
288
256
230
209
192
177
165
154
144
136
128
121
f0,
340,
570,
901,
321,
832,
423,
103,
864,
705,
636,
657,
758,
9310
,20
11,5
613
,00
14,5
216
,13
17,8
2
30 x
4F
3 07
21
536
1 02
476
861
451
243
938
434
130
727
925
623
621
920
519
218
117
116
2f
0,34
0,57
0,90
1,32
1,83
2,42
3,10
3,86
4,70
5,63
6,65
7,75
8,93
10,2
011
,56
13,0
014
,52
16,1
317
,82
35 x
2F
2 09
11
045
697
523
418
348
299
261
232
209
190
174
161
149
139
131
123
116
110
f0,
290,
490,
771,
131,
572,
072,
653,
314,
034,
835,
706,
647,
668,
759,
9111
,14
12,4
513
,83
15,2
8
35 x
3F
3 13
61
568
1 04
578
462
752
344
839
234
831
428
526
124
122
420
919
618
417
416
5f
0,29
0,49
0,77
1,13
1,57
2,07
2,65
3,31
4,03
4,83
5,70
6,64
7,66
8,75
9,91
11,1
412
,45
13,8
315
,28
40 x
2F
2 73
11
365
910
683
546
455
390
341
303
273
248
228
210
195
182
171
161
152
144
f0,
250,
430,
680,
991,
371,
812,
322,
893,
534,
234,
995,
816,
707,
658,
679,
7510
,89
12,1
013
,37
40 x
3F
4 09
62
048
1 36
51
024
819
683
585
512
455
410
372
341
315
293
273
256
241
228
216
f0,
250,
430,
680,
991,
371,
812,
322,
893,
534,
234,
995,
816,
707,
658,
679,
7510
,89
12,1
013
,37
40 x
4F
5 46
12
731
1 82
01
365
1 09
291
078
068
360
754
649
645
542
039
036
434
132
130
328
7f
0,25
0,43
0,68
0,99
1,37
1,81
2,32
2,89
3,53
4,23
4,99
5,81
6,70
7,65
8,67
9,75
10,8
912
,10
13,3
7
40 x
5F
6 82
73
413
2 27
61
707
1 36
51
138
975
853
759
683
621
569
525
488
455
427
402
379
359
f0,
250,
430,
680,
991,
371,
812,
322,
893,
534,
234,
995,
816,
707,
658,
679,
7510
,89
12,1
013
,37
45 x
5F
8 64
04
320
2 88
02
160
1 72
81
440
1 23
41
080
960
864
785
720
665
617
576
540
508
480
455
f0,
230,
380,
600,
881,
221,
612,
062,
573,
143,
764,
435,
175,
966,
807,
718,
669,
6810
,75
11,8
8
50 x
2F
4 26
72
133
1 42
21
067
853
711
610
533
474
427
388
356
328
305
284
267
251
237
225
f0,
200,
340,
540,
791,
101,
451,
862,
312,
823,
383,
994,
655,
366,
126,
947,
808,
719,
6810
,69
50 x
3F
6 40
03
200
2 13
31
600
1 28
01
067
914
800
711
640
582
533
492
457
427
400
376
356
337
f0,
200,
340,
540,
791,
101,
451,
862,
312,
823,
383,
994,
655,
366,
126,
947,
808,
719,
6810
,69
50 x
4F
8 53
34
267
2 84
42
133
1 70
71
422
1 21
91
067
948
853
776
711
656
610
569
533
502
474
449
f0,
200,
340,
540,
791,
101,
451,
862,
312,
823,
383,
994,
655,
366,
126,
947,
808,
719,
6810
,69
50 x
5F
10 6
675
333
3 55
62
667
2 13
31
778
1 52
41
333
1 18
51
067
970
889
821
762
711
667
627
593
561
f0,
200,
340,
540,
791,
101,
451,
862,
312,
823,
383,
994,
655,
366,
126,
947,
808,
719,
6810
,69
60 x
5F
15 3
607
680
5 12
03
840
3 07
22
560
2 19
41
920
1 70
71
536
1 39
61
280
1 18
21
097
1 02
496
090
485
380
8f
0,17
0,29
0,45
0,66
0,91
1,21
1,55
1,93
2,35
2,82
3,32
3,87
4,47
5,10
5,78
6,50
7,26
8,06
8,91
70 x
5F
20 9
0710
453
6 96
95
227
4 18
13
484
2 98
72
613
2 32
32
091
1 90
11
742
1 60
81
493
1 39
41
307
1 23
01
161
1 10
0f
0,15
0,24
0,39
0,57
0,78
1,04
1,33
1,65
2,02
2,41
2,85
3,32
3,83
4,37
4,95
5,57
6,22
6,91
7,64
80 x
5F
27 3
0713
653
9 10
26
827
5 46
14
551
3 90
13
413
3 03
42
731
2 48
22
276
2 10
11
950
1 82
01
707
1 60
61
517
1 43
7f
0,13
0,21
0,34
0,50
0,69
0,91
1,16
1,45
1,76
2,11
2,49
2,91
3,35
3,83
4,33
4,87
5,45
6,05
6,68
90 x
5F
34 5
6017
280
11 5
208
640
6 91
25
760
4 93
74
320
3 84
03
456
3 14
22
880
2 65
82
469
2 30
42
160
2 03
31
920
1 81
9f
0,11
0,19
0,30
0,44
0,61
0,81
1,03
1,29
1,57
1,88
2,22
2,58
2,98
3,40
3,85
4,33
4,84
5,38
5,94
100
x 5
F42
667
21 3
3314
222
10 6
678
533
7 11
16
095
5 33
34
741
4 26
73
879
3 55
63
282
3 04
82
844
2 66
72
510
2 37
02
246
f0,
100,
170,
270,
400,
550,
730,
931,
161,
411,
691,
992,
322,
683,
063,
473,
904,
364,
845,
35H
/200
(m
m)
11,
52
2,5
33,
54
4,5
55,
56
6,5
77,
58
8,5
99,
510
Főb
ord
aosz
tás
(mm
)11
2233
4455
66
Szo
rzó
31,
51
0,75
0,6
0,5
Co
nve
rsio
n m
ulti
pli
ers
for
det
erm
inin
g th
e lo
adin
g ca
pac
ity
of
wal
kway
gra
tin
gs w
ith
oth
er b
ar s
pac
ing
20
01
50
f<
4 m
m
f<
H
f<
HF f
1/2
AB
BA
x
φφ
y
1/2
Not
e:
The
load
ing
can
be
tran
sfer
red
on
to t
he
grat
ing
on
a m
inim
um
200x
200
mm
sur
face
.
F=c
on
cen
trat
ed l
oad
[daN
](~k
g)
f=d
efl e
ctio
n (
mm
)
Designing Aid
14
4.2.2. Evenly distributed loading model
The load of the walkway grating is evenly distributed if the loading force is transmitted onto the grating in an evenly split way. The loading force usually refers to 1 m2 surface.This loading model is applied e.g. upon designing the shelf gratings of high loading capacity of warehouse systems.
Table 4: Loading capacity of the walkway gratings for evenly distributed force in case of 33 mm spacing of the bearing bars
p [
daN
/m2 ]
(k
gN/m
2 ) H
(m
m)
f (m
m)
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
20 x
2F
12 8
005
680
3 15
02
010
1 39
01
020
765
605
490
370
365
285
240
215
190
160
140
130
115
f1,
592,
383,
173,
964,
755,
536,
327,
127,
868,
679,
4010
,18
10,9
411
,84
12,5
713
,44
14,0
614
,55
15,2
8
20 x
3F
19 2
008
530
4 73
03
020
2 09
01
530
1 15
091
074
055
555
043
036
532
028
524
021
020
017
5f
1,59
2,38
3,17
3,97
4,76
5,53
6,34
7,14
7,91
8,67
9,44
10,2
411
,09
11,7
512
,57
13,4
414
,06
14,9
215
,50
25 x
2F
20 0
008
880
4 93
03
140
2 17
01
600
1 20
094
077
058
057
545
038
033
530
025
022
021
018
5f
1,27
1,90
2,54
3,17
3,80
4,44
5,08
5,67
6,32
6,96
7,58
8,23
8,87
9,45
10,1
610
,75
11,3
112
,03
12,5
9
25 x
3F
30 0
0013
330
7 40
04
720
3 26
02
400
1 80
01
420
1 16
087
086
567
557
050
545
037
533
031
528
0f
1,27
1,90
2,54
3,17
3,80
4,44
5,08
5,71
6,35
6,96
7,60
8,23
8,87
9,49
10,1
610
,75
11,3
112
,03
12,7
0
30 x
2F
28 8
0012
800
7 10
04
530
3 13
02
300
1 72
01
360
1 11
083
083
064
554
548
543
036
032
030
026
5f
1,06
1,59
2,12
2,64
3,17
3,70
4,21
4,74
5,27
5,77
6,33
6,83
7,36
7,91
8,43
8,96
9,52
9,95
10,4
3
30 x
3F
43 2
0019
200
10 6
506
790
4 70
03
450
2 59
02
040
1 67
01
250
1 24
097
082
072
564
554
048
045
040
0f
1,06
1,59
2,12
2,64
3,17
3,70
4,23
4,74
5,29
5,79
6,31
6,84
7,38
7,89
8,43
8,96
9,52
9,95
10,5
0
30 x
4F
57 6
0025
600
14 2
009
060
6 27
04
600
3 45
02
730
2 22
01
670
1 66
01
290
1 09
097
086
072
064
060
553
5f
1,06
1,59
2,12
2,64
3,17
3,70
4,23
4,76
5,27
5,80
6,33
6,83
7,36
7,91
8,43
8,96
9,52
10,0
310
,53
35 x
2F
39 2
0017
420
9 66
06
160
4 26
03
130
2 35
01
850
1 51
01
140
1 13
088
074
566
058
549
043
541
036
5f
0,91
1,36
1,81
2,26
2,72
3,17
3,63
4,06
4,52
4,99
5,43
5,87
6,34
6,78
7,22
7,68
8,15
8,56
9,05
35 x
3F
58 8
0026
130
14 5
009
250
6 40
04
700
3 52
02
780
2 27
01
710
1 69
01
320
1 12
099
088
073
565
061
554
5f
0,91
1,36
1,81
2,27
2,72
3,17
3,62
4,07
4,53
4,99
5,41
5,87
6,35
6,78
7,24
7,68
8,12
8,56
9,01
40 x
2F
51 2
0022
750
12 6
208
050
5 57
04
090
3 07
02
420
1 97
01
480
1 47
01
150
970
860
765
640
565
535
475
f0,
791,
191,
591,
982,
382,
773,
173,
563,
954,
344,
735,
145,
535,
926,
326,
727,
097,
487,
89
40 x
3F
76 8
0034
130
18 9
4012
080
8 36
06
140
4 60
03
640
2 96
02
230
2 21
01
730
1 46
01
290
1 15
096
085
080
571
5f
0,79
1,19
1,59
1,98
2,38
2,78
3,17
3,57
3,96
4,36
4,74
5,15
5,54
5,92
6,34
6,72
7,11
7,51
7,92
40 x
4F
102
400
45 5
1025
250
16 1
1011
150
8 19
06
140
4 85
03
950
2 97
02
950
2 31
01
950
1 72
01
530
1 28
01
130
1 07
095
0f
0,79
1,19
1,59
1,98
2,38
2,78
3,17
3,57
3,96
4,35
4,75
5,16
5,55
5,92
6,32
6,72
7,09
7,48
7,89
40 x
5F
128
000
56 8
8031
570
20 1
3013
930
10 2
407
680
6 06
04
940
3 72
03
690
2 88
02
430
2 16
01
920
1 60
01
420
1 34
01
190
f0,
791,
191,
591,
982,
382,
783,
173,
573,
964,
364,
755,
145,
545,
956,
356,
727,
137,
507,
91
45 x
5F
162
000
72 0
0039
960
25 4
8017
640
12 9
609
720
7 68
06
260
4 71
04
680
3 65
03
080
2 73
02
430
2 03
01
800
1 70
01
510
f0,
711,
061,
411,
762,
122,
472,
823,
173,
533,
884,
234,
584,
935,
285,
645,
996,
356,
687,
05
50 x
2F
80 0
0035
550
19 7
3012
580
8 71
06
400
4 80
03
790
3 09
02
320
2 31
01
800
1 52
01
350
1 20
01
000
880
840
740
f0,
630,
951,
271,
591,
902,
222,
542,
863,
173,
483,
814,
124,
434,
765,
085,
385,
666,
026,
29
50 x
3F
120
000
53 3
3029
600
18 8
8013
060
9 60
07
200
5 68
04
640
3 49
03
460
2 70
02
280
2 02
01
800
1 50
01
330
1 26
01
120
f0,
630,
951,
271,
591,
902,
222,
542,
853,
173,
493,
804,
124,
434,
755,
085,
385,
706,
026,
35
50 x
4F
160
000
71 1
1039
460
25 1
7017
420
12 8
009
600
7 58
06
180
4 65
04
620
3 61
03
040
2 70
02
400
2 00
01
770
1 68
01
490
f0,
630,
951,
271,
591,
902,
222,
542,
863,
173,
493,
814,
134,
434,
765,
085,
385,
696,
026,
34
50 x
5F
200
000
88 8
8049
330
31 4
6021
770
16 0
0012
000
9 48
07
730
5 81
05
770
4 51
03
800
3 37
03
000
2 50
02
220
2 10
01
860
f0,
630,
951,
271,
591,
902,
222,
542,
863,
173,
493,
804,
124,
434,
755,
085,
385,
716,
026,
33
60 x
5F
288
000
128
000
71 0
4045
310
31 3
6023
040
17 2
8013
650
11 1
308
370
8 32
06
490
5 48
04
860
4 32
03
610
3 20
03
030
2 68
0f
0,53
0,79
1,06
1,32
1,59
1,85
2,12
2,38
2,64
2,91
3,17
3,43
3,70
3,96
4,23
4,49
4,76
5,02
5,28
70 x
5F
392
000
174
220
96 6
9061
670
42 6
8031
360
23 5
2018
580
15 1
5011
400
11 3
208
840
7 46
06
620
5 88
04
910
4 35
04
120
3 65
0f
0,45
0,68
0,91
1,13
1,36
1,59
1,81
2,04
2,27
2,49
2,72
2,95
3,17
3,40
3,63
3,85
4,08
4,30
4,52
80 x
5F
512
000
227
550
126
290
80 5
5055
750
40 9
6030
720
24 2
7019
790
14 8
9014
790
11 5
509
750
8 64
07
680
6 42
05
680
5 38
04
770
f0,
400,
600,
790,
991,
191,
391,
591,
791,
982,
182,
382,
582,
782,
973,
173,
373,
573,
763,
96
90 x
5F
648
000
288
000
159
840
101
950
70 5
6051
840
38 8
8030
720
25 0
5018
850
18 7
2014
620
12 3
4010
940
9 72
08
130
7 20
06
820
6 04
0f
0,35
0,53
0,71
0,88
1,06
1,23
1,41
1,59
1,76
1,94
2,12
2,29
2,47
2,64
2,82
3,00
3,17
3,35
3,52
100
x 5
F80
0 00
035
5 55
019
7 33
012
5 86
087
110
64 0
0048
000
37 9
2030
930
23 2
7023
110
18 0
5015
230
13 5
1012
000
10 0
308
880
8 42
07
460
f0,
320,
480,
630,
790,
951,
111,
271,
431,
591,
751,
902,
062,
222,
382,
542,
702,
853,
023,
17H
/200
(m
m)
11,
52
2,5
33,
54
4,5
55,
56
6,5
77,
58
8,5
99,
510
Főb
ord
aosz
tás
(mm
)11
2233
4455
66
Szo
rzó
31,
51
0,75
0,6
0,5
Co
nve
rsio
n m
ulti
pli
ers
for
det
erm
inin
g th
e lo
adin
g ca
pac
ity
of
wal
kway
gra
tin
gs w
ith
oth
er b
ar s
pac
ing
20
01
50
f<
4 m
m
f<
H
f<
HF f
1/2
AB
BA
x
φφ
y
1/2
p=e
ven
ly
dis
trib
uted
lo
ad[d
aN/m
2 ](~
kg/m
2 )
f=d
efl e
ctio
n
(mm
)
NAGÉV
a (m
m)
100
150
200
250
300
400
500
600
b (
mm
)10
015
020
020
020
020
020
020
0
ba
4.2.3. Dynamic loading model
In case of a load changing fast in time, being impulsive or repeating periodically the dynamic loading model allows the test of the loads generated by the vehicles. Due to the extreme dynamic forces arising from starting and braking of the vehicles μ = 1.3 dynamic factor has to be calculated with in accordance with DIN 1072.
Table 5: Loading capacity of the walkway gratings for dynamic force in case of 33 mm spacing of the bearing bars
15From
the
tab
le t
he g
rati
ng t
ype
nece
ssar
y fo
r b
rid
ging
the
sp
ecifi
c H
op
enin
g ca
n b
e se
lect
ed b
y co
nsid
erin
g th
e lo
ad-t
rans
fer
surf
aces
and
the
val
ue o
f th
e w
heel
pre
ssur
e gi
ven
in a
ccor
dan
ce w
ith
DIN
107
2 m
ulti
plie
d b
y μ=
1,3
dyn
amic
fac
tor.
For
exa
mp
le: s
pec
ifi c
F=10
00 d
aN w
heel
pre
ssur
e, H
=100
0 m
m s
upp
ort
spac
ing,
A=2
00x2
00 m
m lo
ad
tran
sfer
sur
face
. Sol
utio
n: t
he d
ynam
ic w
heel
pre
ssur
e is
F=1
300
daN
. Goi
ng f
rom
the
A=2
00x2
00 m
m fi
eld
to
the
righ
t, w
e se
ek f
or t
he le
ngth
val
ue f
ulfi l
ling
the
H>1
000
mm
co
ndit
ion.
The
typ
e of
the
gra
ting
sui
tab
le f
rom
the
poi
nt o
f vi
ew o
f st
reng
th c
an b
e fo
und
in t
he t
op in
the
col
umn
of t
his
valu
e. In
acc
ord
ance
wit
h th
e ex
amp
le t
he N
AGÉV
w
alkw
ay g
rati
ng o
f 60
x5 g
rati
ng t
ype,
33/
33 b
ar s
pac
ing
mee
ts t
he s
pec
ifi c
req
uire
men
ts. I
n ca
se o
f a
smal
ler
load
tra
nsfe
ring
sur
face
the
line
bel
ongi
ng t
o th
e d
ynam
ic w
heel
p
ress
ure
is s
elec
ted
Din
amik
us
keré
knyo
más
[d
aN]
(~kg
)
Terh
elés
t át
adó
felü
let
Rác
stíp
us
20 x
220
x 3
25 x
225
x 3
30 x
230
x 3
30 x
435
x 2
35 x
340
x 2
40 x
340
x 4
40 x
545
x 5
50 x
250
x 3
50 x
450
x 5
60 x
570
x 5
80 x
590
x 5
100
x 5
[mm
x m
m]
H (
mm
)
520
100
x 10
010
014
015
021
020
030
039
027
040
035
051
068
084
01
060
530
790
1 05
01
300
1 87
02
530
3 30
04
170
5 15
015
0 x
150
150
200
210
300
290
420
550
380
560
490
720
950
1 18
01
490
750
1 11
01
470
1 83
02
620
3 55
04
630
5 85
07
210
200
x 20
018
024
025
035
034
049
064
045
065
057
083
01
100
1 36
01
710
870
1 28
01
690
2 10
03
000
4 07
05
300
6 69
08
250
650
100
x 10
090
120
120
170
170
240
320
220
320
280
410
550
680
850
430
640
840
1 05
01
500
2 03
02
650
3 34
04
120
150
x 15
012
017
018
025
024
034
045
031
045
040
058
077
095
01
200
610
890
1 18
01
470
2 10
02
850
3 71
04
680
5 78
020
0 x
200
150
200
210
290
280
400
520
370
530
470
680
890
1 10
01
370
700
1 03
01
360
1 69
02
410
3 26
04
250
5 36
06
610
975
100
x 10
060
9090
120
120
170
220
150
220
200
280
370
460
570
290
430
570
700
1 00
01
360
1 77
02
240
2 76
015
0 x
150
9012
013
018
017
024
031
022
031
028
040
052
065
081
042
061
080
099
01
410
1 91
02
480
3 13
03
860
200
x 20
012
015
015
021
020
028
036
026
037
033
047
061
075
093
048
070
092
01
140
1 62
02
190
2 85
03
590
4 42
0
1 30
010
0 x
100
5070
7010
090
130
170
120
170
150
220
280
350
440
230
330
430
530
760
1 03
01
330
1 68
02
070
150
x 15
080
100
100
140
140
190
240
170
240
220
310
400
490
610
320
460
610
750
1 07
01
440
1 87
02
360
2 90
020
0 x
200
100
120
130
170
160
220
280
210
290
260
360
470
570
710
370
540
700
870
1 23
01
650
2 15
02
700
3 33
0
1 95
015
0 x
150
6080
8010
010
014
017
013
017
016
022
028
034
042
022
032
042
051
072
097
01
260
1 58
01
950
200
x 20
080
100
100
130
120
160
200
150
210
190
260
330
400
490
260
370
480
590
830
1 12
01
450
1 82
02
230
2 60
020
0 x
200
7080
9011
010
013
016
013
017
015
020
026
031
038
021
029
037
046
064
085
01
100
1 37
01
690
200
x 25
080
9010
012
012
016
019
015
020
018
024
031
037
046
025
035
046
056
078
01
050
1 36
01
710
2 10
0
3 90
020
0 x
200
6070
7090
8010
012
010
013
012
015
019
022
027
015
021
026
032
044
058
075
093
01
140
200
x 25
070
8080
100
9012
014
011
015
013
018
022
026
032
018
025
032
039
054
072
092
01
150
1 41
0
5 20
020
0 x
300
6070
8090
9011
013
011
014
012
016
020
024
029
017
023
029
035
049
065
083
01
040
1 28
020
0 x
400
7080
8010
010
013
016
012
016
014
019
024
029
036
020
028
035
043
060
080
01
030
1 29
01
580
6 50
020
0 x
300
6070
7080
8010
012
090
120
110
140
170
200
240
140
190
240
290
400
530
680
840
1 03
020
0 x
400
6070
8090
9011
013
011
014
012
016
020
024
029
017
023
029
035
049
065
083
01
040
1 28
020
0 x
500
7080
8010
010
012
015
012
015
014
019
023
028
034
019
027
034
041
058
077
099
01
240
1 52
0
8 70
020
0 x
300
6060
6070
7080
100
8010
090
120
140
160
190
120
160
190
230
310
410
520
640
780
200
x 40
060
7080
9090
110
130
110
140
120
160
200
240
290
170
230
290
350
490
650
830
1 04
01
270
200
x 50
060
7070
9080
100
120
100
130
120
150
190
220
270
160
210
270
320
440
590
750
940
1 15
0
9 75
020
0 x
400
6060
7080
7090
100
9011
010
012
015
018
021
013
017
021
025
034
045
057
071
087
020
0 x
500
6070
7080
8010
012
090
120
110
140
170
200
240
140
190
240
290
400
530
680
840
1 03
020
0 x
600
6070
8090
9011
013
010
013
012
016
020
024
029
017
023
029
035
048
063
082
01
020
1 25
0
13 0
0020
0 x
500
6060
6070
7080
100
8010
090
120
140
160
190
120
160
190
230
310
410
520
640
780
200
x 60
060
7070
8080
9011
090
110
100
130
160
190
230
140
180
230
270
370
490
620
780
950
Designing Aid
16
4.3. Other designing hints
4.3.1. General tips
- If possible, provide all walkway gratings with an identifi er.- Aim at the same marking of the identical gratings upon dividing the platform of large surface covered with more walkway gratings.
- If one or two profi le walkway gratings are each other’s mirror image, they should get a different marking.- In order to prevent the shape- and size deformations arising during hot-dip galvanizing avoid such grat-ings where there is a proportionally large size difference between the sides “H” and “L” (H/L > 1/15).
- Select an appropriate receiving structure for the specifi c bearing bar height (e.g. for a 33 mm high grating hot rolled L35x35x4 mm frame element).
- Such solutions should be avoided, where it is complicated or impossible to obtain a hot rolled angle steel used to receive the walkway grating (e.g. for a 55 mm high walkway grating 55 mm frame element).
- In case of a walkway grating loaded with vehicle traffi c the direction of the bearing bar should be the same as the direction of the traffi c, if possible.
- Instead of arched contours use sections. For example, for rolling down circular ring platforms of large diameter apply trapezoid gratings of similar shape instead of the gratings of circular ring section shape.
- Design a mounting gap between the walkway gratings (see Chapter 4.3.6).
4.3.2. Conditions related to the bearing bar
- The bearing bars should be placed perpendicularly to the longitudinal axis of the support.- Avoid the application of the walkway gratings of bearing bar direction not perpendicular to the sup-ports (“nun grating”).
- The supporting structure shall be formed in such a way that the length of support of the bearing bars should be larger or the same as the height of the bearing bar, but it should reach minimum 30 mm.
- The size of bearing bar direction is indicated by the fi rst dimension number.
4.3.3. The rules of the bar spacing
- Under the effective law the bar spacing of the walkway gratings installed in public areas may be maximum 22 / 22 mm. For the step slabs, terrace- and trench gratings of family houses it is also rec-ommended to select smaller bar spacing than the standard 33 / 33 mm.
- If the walkway grating is designed for pedestrian traffi c, avoid the use of products of larger bar spac-ing than the usual.
4.3.4. The construction of the tread
If the walkway grating is designed for pedestrian traffi c and the walkway grating is installed in a slip-pery, oil environment, or the angle of intersection of the application surface with the horizontal plane exceeds 2°, installation of walking gratings made skid-proof is recommended.The tread may be classifi ed further on the basis of the extent of making skid-proof:
- bearing- and crossbars without making them skid-proof (smooth thread; in accordance with some standards R10)
- only the crossbar is made skid-proof (R11)- both the bearing bar and the crossbar are made skid-proof (CSM2; R12)
The bars of the walkway gratings can be made skid-proof up to 5 mm sheet thickness.Ask for our workers’ assistance for the possibility to make the walkway gratings with different bar spacing than 33 / 33 mm skid-proof.While upon the application of the gratings with CSM2 thread due to the decrease of the cross-section the loading capacity also decreases, for the CMS4 type developed and patented by NAGÉV RÁCS Kft. the bearing capacity remains 100%. Another great advantage of the CSM4 tread is the substantially better adherence. Theoretically, the beading of the gratings would contact the foot-wear only at one point, but as a consequence of the different fl exibility of the materials and the action-reaction the less resistant shoe sole “clings to” the harder, prominent beading. The force distributed on the larger surface provides greater adhesion friction in comparison with the smooth walkway gratings or those with CMS2 thread.
NAGÉV
17
The skidding properties related to the different treads are characterized by the size of the angle (α) belonging to skidding of the load and the height of the slope (h). Our measurements carried out in accordance with DIN 51130:1991 are summarized in Table 6.
Table 6: Skidding properties of the threads
4.3.5. Conditions related to the size and shape
- Upon determining the dimensions of the walkway grating it is worth keeping the manufacturing size ranges, as well as the hot-dip galvanizing, packaging, transport and installation conditions in mind. The well-considered designing facilitates, accelerates the installation, moreover, it does not endanger the safety of working.
- Avoid designing square gratings. If it cannot still be resolved, it shall be ensured that the direction of the bearing bars and crossbars cannot be inverted, when they are installed.
- Aim at designing as many square walkway gratings, i.e. those belonging to the NORMAL subcate-gory as possible.
- The large profi le gratings (1.5 m2<Territory<2 m2) should preferably be cut off into smaller-size NORMAL and profi le sections.
- Use as many gratings of the same size as possible to cover a specifi c surface.- The territory of the walkway gratings should be in the range between 0.71 m2 and 2.0 m2, if pos-sible.
- Avoid designing gratings with breakthrough loaded by extra charges, which can be installed in a complicated way. The breakthrough of the walkway grating adversely infl uences the loading ca-pacity of the gratings. In such a case its effect exercised on its loading capacity shall be taken into consideration, and appropriate supporting of the bearing bars affected by the breakthrough shall be provided for. At the same time the mountability of the fi tting, pipeline, support going through the breakthrough of the grating shall be kept in mind.
- Aim at simplifying, combining the cutouts. The cutouts, breakthroughs near each other should be “torn’ into one piece.
- Instead of arched cutouts with a radius smaller than R = 300 mm located in the contour of the walkway gratings, apply cutouts parallel with the sides of the gratings, limited with sections. If the application of the arch is still unavoidable, carry out bordering of the arcs with a radius small-er than R = 120 mm with fl at steel for both frame types.
- In relation to the profi le it has to be noted that the beginnings of the bearing bars and crossbars of the NORMAL and profi le gratings of the same overall dimensions and type (the distance of the fi rst bearing bar or crossbar measured from the inside edge of the frame element) are not the same in any case. (In case of gratings installed next to each other the bars do not “run”.)
- If possible, the overall dimensions of the walkway- and stair gratings should be divided by 5.- It is worth placing the barrier surrounding the platform in the external fl ange of the structure, since in this way designing of profi le gratings resulting from the connection of the barrier posts can be avoided.
Our grating products are supplied with a 59x38 mm NAGÉV® trade mark made from 0.75 mm thick steel sheet on the tread.
Grating type Tread
Load transfering
surfaceWooden pallet Metal tool crib Rubber-sole shoes
Quality of the surfaces Dry Wet Oily Dry Wet Oily Dry Wet Oily
h [mm] 600 720 490 280 260 240 540 520 450
30x2 α 23° 28° 19° 10,7° 10° 9° 21° 20° 17°
h [mm] 680 730 600 340 300 280 610 590 510
30x2 CSM2α 27° 29° 23,5° 13° 11,5° 10,7° 24° 23° 20°
h [mm] 920 900 780 360 350 350 740 730 690
30x2 CSM4 α 38° 36° 31° 14° 13,5° 12° 30° 29° 27°
Designing Aid
18
4.3.6. Mounting gap
Upon division, designing, installation of treads used to cover steel platforms of a specifi c size, rela-tively large extent a mounting gap shall be applied between the walkway gratings. The mounting gap and its size are accounted for or infl uenced by the following factors:
- the size, proportions, complexity of the area to be covered- the type, geometrical shape, overall dimensions of the walkway grating- the geometrical- and dimensional tolerance of the walkway grating- fastening of the walkway grating- other accessories placed onto the walkway grating (e.g. ankle rail)- construction of the supporting- and receiving element- the tolerances of the steel structure supporting the gratings- the extent of thermal expansion- the contaminating impact of the work and technology executed on the walkway grating
In accordance with several decades’ designing and manufacturing experience of NAGÉV RÁCS Kft. the recommended size of the mounting gap is 5-15 mm.
4.3.7. Supporting structures
For industrial application of the walkway gratings it is practical to construct the supporting structure from a kind of hot rolled, open EURO section. It has several advantages:
- appropriate strength features- commercially easily available- easy formability, mountability- it conforms to the hot-dip galvanizing technology- fastening of the walkway gratings, stairs can be easily resolved
If another section is selected, the proper fastening, keeping in position, orientation of the gratings shall be provided for by placing mounting lugs or other accessories.
4.4. Fittings of the walkway gratings
On demand, the walkway gratings are provided with an appropriate number of fi ttings of proper posi-tion. E.g. ankle rail, safety leading edge (BB-edge), mounting sideplate, strap, handle, padlock loop, fi xing lug, etc. However, there are such situations, when the intended use of the gratings almost com-pulsorily entails the necessary accessories (for example, stairs, landings).
4.4.1. Ankle rail
The ankle rail is such a fi tting made from fl at steel, which prevents skidding down of the objects, tools used on the walkway gratings and the legs of the people going on the grating, stretching above the thread. If the walkway gratings is built in at a relatively large height and the placement of the ankle rail cannot be resolved in any other way – mounted on a protective barrier, supporting structure –, the application of an ankle rail is recommended on the edges of the walkway gratings. The recommended height of the ankle rail may be between 60x5 mm and 150x5 mm.
NAGÉV
19
In case of fl at steel bordering the ankle rail is constructed by increasing the height of the frame element (m2) (Fig. 12).
Fig. 12: Ankle rail on a fl at steel framed grating
4.4.2. Safety leading edge (BB-edge)
It is a perforated fi tting located in the treading side for the stair-, landing- and exit gratings. Its ap-plication is accounted for from security and worker protection point of view, since it signifi cantly increases the adherence between the edge of the grating and the shoe sole.NAGÉV RÁCS Kft. uses the leading edges shown in Fig. 13 – depending on the technology – for the different grating products.
Fig. 13: Types of the BB-edge
4.4.3. Mounting sideplate
It is the drilled steel plate used for fastening the stairs and landing gratings, which is usually located in two parallel – perpendicular to the bearing bar – sides of the grating (Fig. 14).
Fig. 14: Position of the mounting sideplate
h
70
Mounting plate - 70x3
Bearing bar
Crossbar
hm
2
Designing Aid
20
4.5. Fastening of the walkway gratings
The different fastening fi ttings of NAGÉV RÁCS Kft. mean the solution for the fast, disconnectable con-nection between the walkway gratings and the supporting structure. Fastening of the gratings is rec-ommended at 4 points by square meter and/or grating slab. To fasten two or more neighbouring walk-way gratings to each other a fastening fi tting of grating-grating type is recommended.The fastening fi ttings are not part of the walkway gratings, can be ordered as an option.
The construction of the fastening fi ttings and the fastening possibility of the walkway gratings are as follows.
4.5.1. Fastening fi tting 33
For 33 mm and 34 mm bar spacing, up to 5 mm thickness of the bearing bar, in a hot-dip galvanized design (lower element + upper element + DIN 933 M8x70 full-thread bolt, strength class 5.6 + DIN 557 M8 quadrangle nut, strength class 5) (Fig. 15).
Fig. 15: Fastening fi tting 33
4.5.2. Fastening fi tting 22
For 22 mm bar spacing, up to 3 mm thickness of the bearing bar, in a hot-dip galvanized design (lower element + upper element + DIN 912 M8 internal opening bolt + DIN 557 M8 quadrangle nut, strength class 5) (Fig. 16).
Fig. 16: Fastening fi tting 22
NAGÉV
21
4.5.3. Grating-grating fastening fi tting
For 33 mm and 34 mm bar spacing, up to 5 mm thickness of the bearing bar, in a hot-dip galvanized design (lower element h=150 mm + 2 pc upper elements + 2 pc DIN 933 M8x70 full-thread bolts, strength class 5.6 + 2 pc DIN 557 M8 quadrangle nuts, strength class 5) (Fig. 17).
Fig. 17: Grating-grating fastening fi tting
4.5.4. Hooked fastening fi tting
For 33 mm and 34 mm bar spacing, up to 5 mm thickness of the bearing bar, in a hot-dip galvanized design (Ø mm bent, threaded round steel + DIN 557 M8 hexagonal nut, strength class 5) (Fig. 18).
Fig. 18: Hooked fastening fi tting
Designing Aid
22
4.5.5. Stainless fastening fi tting
For 33 mm and 34 mm bar spacing (lower element + upper element + DIN 933 M8x70 full-thread bolt + DIN 934 M8 hexagonal nut A2). Its construction is the same as shown in Fig. 16.
4.5.6. Fastening fi tting 11
For 11 mm bearing bar and crossbar spacing, up to 3 mm thickness of the bearing bar, in a hot-dip galvanized design (lower element + DIN 7985 M8x70 full-thread bolt, strength class 4.8 + DIN 557 M8 quadrangle nut, strength class 5) (Fig. 19).
Fig. 19: Fastening fi tting 11
5. The Dimensional- and Geometrical Tolerances of the Walkway Gratings
The following dimensional- and geometrical tolerances are valid for the walkway gratings of maximum 2,000 mm side size and 2 m2 area.
5.1. Length tolerances of bearing bar- (H) and crossbar (L) direction
The technology applied by NAGÉV RÁCS Kft. meets the requirements of dimensional accuracy from all points of view. The tolerances applying to the overall dimensions (H, L) and the grating spacing (t1, t2) are specifi ed in Tables 7 and 8.
Table 7: Tolerances of the normal gratings
Table 8: Tolerances of the bar spacing Fig. 20: Tolerances of the normal gratings
5.2. The length difference of the diagonals
The angle preservation is given by the deviation of the length of the diagonals measured to each other, expressed in percentage. For NORMAL walkway gratings the length of the diagonals may deviate from each other by maximum 0.5 %. The tolerances of the diagonals are determined in accordance with the following formula: Amax–Amin ≤ 0,005 x Amin
Size [mm] Tolerance [mm]
<500 -2; 0
501-1000 -3; 0
1001-1500 -4; 0
1501-2000 -5; 0
Bar spacing [mm] Tolerance [mm]
t1; t2 +0.5
L
H
t2
t1
A1
A2
NAGÉV
Fig. 21: Tolerances of the cutouts
Fig. 22: Convexity shape inaccuracies
Fig. 23: Concavitiy shape inaccuracies
23
5.3. Tolerances of the cutouts
The dimensional accuracy of the cutouts of the grat-ing (e, f) is of decisive importance from the applicabil-ity of the profi le walkway gratings. The allowable val-ues are shown in Table 9.
Table 9: Tolerances of the cutouts
5.4. Tolerances of shape inaccuracies
The manufacturing operations of the products (pressing, welding, framing) may cause unwanted changes in the shape, but these should not restrict the usability of the walkway gratings. The bearing bars and/or crossbars may bend above the theoretical plane of the thread or arched below it (convexity: Fig. 22, concavity: Fig. 23). The allowable size of the faults of fl atness depends on the bar length. The values of the deviations (a, b) are shown in Tables 10 and 11.
Table 10: Convexity shape inaccuracies
Table 11: Concavity shape distortions
Size [mm] Tolerance [mm]
e; f 0; +8
If the bar length is
a>450 [mm] ≤450 [mm]
< bar length/150, but max. 8 ≤ 3
If the bar length is
b>600 [mm] ≤600 [mm]
< bar length/200, but max. 5 ≤ 3
H
f
e
L
aa
bb
Designing Aid
24
5.5. Skewness of the bearing bar, skew end-cutting
The bearing bars are manufactured on automated equipment. In spite of this, when end cutting or pressing such deviations (p) may occur, which shall be strictly limited (Fig. 24).
p ≤ 2 mm
Fig. 24: Skewness of the bearing bar, skew end-cutting
5.6. The protrusion of the crossbar
After pressing the crossbars may raise from the plane of the tread to a minimum extent. The value of the deviation (q) is shown in Fig. 25.
q ≤1 mm
Fig. 25: Protrusion of the crossbar
5.7. The overhang of the frame element
The protrusion of the fl at steel frames measured from the tread, and its stretching down understood from the lower plane of the grating (r) were established in compliance with the other tolerances (Fig. 26).
r ≤ 1 mm
Fig. 26: The overhang of the frame element
5.8. The overhang of the crossbar on the outermost bearing bar or the frame element
For the appropriate bonding strength of the bearing bar and the crossbar the crossbar shall entirely fi ll the gap cut out in the bearing bar for it. The overhang of little extent of the crossbar (s) is allowable in this case if it does not disturb the usability of the product (Fig. 27).
s ≤ 1,5 mm
Fig. 27: The overhang of the crossbar
5.9. The torsion of the walkway grating
The fourth corner point may deviate from the plane formed by any three corner points of the walkway grating by + 3mm.
b
S
r
rP P
K K
NAGÉV
25
6. ProductsWe meet different applications of the industrial walkway gratings in several areas of everyday life. Below we present the most general possibilities of the use of the products of NAGÉV RÁCS Kft.
6.1. Industrial walkway grating
It is a grating product primarily used to cover the steel structures of construction industry investments, industrial installations, but it is more and more popular in other areas as well by recognizing and exploit-ing its varied possibilities of application.
6.2. Stair grating
The stair grating is used to construct the tread of the stair structures raising in a straight line or in an arch. Nowadays it has gained more and more ground for the outdoors and internal steps of residential-houses, condominiums and family houses, as well as holiday homes and public institutions.
Basically three types are distinguished in accordance with the shape of the stair grating:- straight, H x L sized “traditional” stair (Fig. 28);- drawn, i.e. having any regular or irregular polygon shape (Fig. 29);- and those stairs that can be fi tted to spiral staircases, generally circular ring section or trapezoid shaped (Fig. 30).
The stair grating is such an individually constructed walkway grating, where safety leading edges are placed onto its entering side (in parallel with the bearing bar), and mounting plates are placed onto its two short-er sides. The stair can be fastened to the fl ight of stair by means of holes formed in the mounting plates. The stairs are made in accordance with the specifi cations of DIN 24531.
Fig. 28: Stair
Fig. 29: Drawn stair Fig. 30: Spiral stair
BB-él
H
L
35
Ø13
15
30
70
13
30
x3
L – 120
L
Mounting plate
Designing Aid
26
The overall dimensions of the stair gratings introduced by NAGÉV RÁCS Kft. are varying between the following limits:
- width (H): 600-1200 mm (with a scale of 5 mm);- entering depth (L): 230-330 (with a scale of 5 mm).
The cross-sections of the bearing bar belonging to the stairs:- 30x2; 30x3; 40x2; 40x3.
The sizes of the frequent stairs of bearing bar and crossbar direction are summarized in Table 12.
Table 12: Frequent stair sizes
We can undertake the manufacture of stairs of other type, size, construction after preliminary discus-sion.
6.3. Board grating
The board grating is a pressed walkway grating having large overall dimensions. Its advantages are the precise cutting to size that can be carried out in the workshop or on the spot, and the short manufac-turing deadline. The subsequent cutting to size is recommended only in natural design, i.e. without hot-dip galvanizing.
The frequent bearing bar cross-sections belong-ing to the board gratings:
- 25x2; 30x2; 30x3; 35x2; 35x3; 40x2; 40x3.
Our board gratings are made with the following bar spacings:
33 / 22; 33 / 33; 33 / 44; 33 / 66; 66 /33
Our board gratings are manufactured with smooth and CSM2 tread. The board gratings are made in the nominal sizes as per Table 13.
Size of bearing bar direction – H [mm] Size of crossbar direction – L [mm]
600
240
250
270
800
240
250
270
900
240
250
270
1000
240
250
270
300
1200
240
250
270
300
Size of bearing bar direction [mm]
Size of crossbar direction [mm]
3000 1000
3000 1200
6000 1000
6000 1200
13. táblázat: Járatos táblarácsméretek
NAGÉV
27
6.4. Drainage systems
Under the following weather conditions due to the heavy rainfalls the safe drainage of the rainwater falling suddenly in great amount has to be provided for. The grated trench of NAGÉV offer a solution for this, which are steel structures of long service life, high load-bearing capacity, to be built into the road- and outdoors pavement made with walkway grating cover.
Application alternatives:- rainwater drainage- drainage in front of deep-level garages- industrial water drainage of factories, plants- covering of trench channels crossing the road surface
Basically two constructions are distinguished:1. NC-21: The structure receiving the grating is made of rolled angle steel adjusted to the bearing bar size of the grating, which is supplied with an appropriate number of wall anchors in an appropriate position. The channel used to conduct the liquid is constructed from square concrete cast on the spot. Upon designing the product it is worth keeping the commercially available sizes of the L-steels , and the considerations of transport in mind (Fig. 31).
Fig. 31: NC-21 typed drainage
2. NC-22: In this version the trench body is made of steel sheet, thereby eliminating the adverse properties of the trenchess constructed from the prefabricated concrete elements or the square concrete cast on the spot. The product constructed as a result of multi-stage development can be built in faster, has longer service life and better resistance to the dynamic loads. The product is manufactured in standard sizes, however, after rec-onciliation there is a possibility to satisfy individual requirements be-sides taking the available board sheet sizes and layout of the trench body into consideration (Fig. 32). Fig. 32: NC-22 typed drainage
External dimension of the frame
Wall anchor
Wall anchor
L-steel
Concrete
Internal dimension of the shaft
Trench grating
Trench grating
Trench body
Designing Aid
28
6.5. Scraper grating
The technical construction of the doormat grating is similar to the rainwater drainage system marked NC21 presented beforehand. Upon the concrete work of the frame a “bay” is formed under the door-mat so that the contamination falling through the grating during the use can be easily removed. The mud-scraping capacity of the grating is increased in such a way that the crossbars perpendicular to the travel direction are supplied with beading (CSM4) (Fig. 33).
The advantages of our doormats:- simple, fast installation- lightweight construction- effi cient mud-scraping- safe treading- easy to keep clean- removable grating panel- long service life
Fig. 33: Doormat grating
6.6. Ventilation well grating
The ventilation well is used to ventilate, illuminate the rooms being below the surface of the ground of the buildings, but having windows. The ventilation well is constructed sunk into the ground in front of the window. By means thereof the room and the walls can be kept dry, since the ground- and rainwater is collected in the bottom of the ventilation well. Its application cannot be neglected from the point of view of energy onsumption, since a certain degree of natural illumination can be achieved through the ventilation well. The cover of the ventilation wells, protection against intrusion and vandalism are pro-vided by the walkway grating used to cover it, as well as the frame used for positioning it.Upon designing the grating the position of the supported sides and the function of the specifi c ventila-tion well shall be taken into consideration:1. Our aim is to let as much light into the ventilation well as possible. At this time the direction of the
bearing bar is perpendicular to the plane of the wall, therefore the one of the two parallel supporting structures has to be fastened onto the wall.
2. Illumination is not a consideration or is not the most important consideration. In this case we can also use gratings with a bearing bar running in parallel with the wall, so the support fastened onto the wall is not necessary.
6.7. Screening grid
In accordance with the specifi cations of the National Settlement Planning and Construction Require-ments (OTÉK), during designing and implementation of the frontals of the new buildings the protection against the excessive summer warming, i.e. the “sun-path”, has to be provided for with architectural devices (e.g. external screen). The walkway gratings developed by NAGÉV RÁCS Kft., having an identi-cal bearing bar and crossbar, of low net weight are also suitable for screening.Our screening grids of this type are manufactured with not more than 60 mm bearing bar height.
External size of the frame
Scraper gratingConcrete
Wall anchor
L-steel
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6.8. Tree foot grating
The tree foot grating (tree protecting grat-ing) consists of a removable grating made from two pieces and the related frame that can be concreted in, so it can be built in either subsequently. In this case the frame is also made from two pieces. The construction allows the watering of the plant, leakage of the collected rainwater, at the same time by removing the gratings the soil cultivation around the trunk can be easily executed. Our tree foot gratings manufactured on the basis of individual requirements can be built in the squares, promenades, parking places of shopping centres (Fig. 34).
Fig. 34: Tree foot grating
6.9. Staircase structures
6.9.1. About the staircase in general
The staircase is a part of the industrial establishments, buildings, residential houses of decisive im-portance. NAGÉV RÁCS Kft. offers different staircase constructions to bridge the level differences, which can be with straight- and broken fl ight of stairs, drawn stairs, as well as spiral staircases. On the basis of their intended use we can speak about, for example, industrial outdoors and interior, rescue- and fi re-escape staircases, attic stairs, staircases of family houses and condominiums.
The general design regulations for staircases are determined by the provisions of Article 63-67.§ of Governmental Decree 253 / 1997 (XII. 20.) on the National Settlement Planning and Construction Requirements.
Upon designing the staircase structures the following key aspects shall be taken into consideration:- type, intended use of the staircase- tread width, direction of travel- on the spot installation, space requirements- fastening of the structure- 2m+sz=630 mm; m=unit rise, or riser height, sz=unit run, or tread width; (Francois Blonder rule)- the number, shape, fastening of the stairs, landings- in case of unlined design steps need to be designed with coverage- one fl ight of stair may contain not more than 20 risers, thereafter a landing shall be inserted- the depth of the landing is usually the same as the width of the fl ight of stairs- placement of safety accessories (e.g protective barriers, ankle rails, safety leading edges)- the usual barrier height is between 900-1100 mm
Our staircase structures are characterized by appropriate strength properties, light structural ele-ments, construction of module structure, bolted connections, fast installation and adequate stability. Our staircases are primarily made in hot-dip galvanized design, but can also be ordered with either duplex surface protection.
Break-through
Gratings
L-frame
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30
Az acéllépcsőkkel kapcsolatos fogalmakat a 35. ábrán foglaltuk össze.
Fig. 35: Steel staircase
Exit platform
A section
Barrier post
Unit run
Overlapping
Hand guide
Space rail
Base plate
Lépcsőfok
Length
Width
Tread width
Flight of stairs
Uni
t ri
se
Bar
rier
hei
ght
Ove
rlap
ping
hei
ght
Carriage
Stair
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6.9.2. Connections of the stair-supporting structure
Several solutions are offered to fasten the stairs to the supporting structure. From them exclusively the variations used most, considered as the most favourable by NAGÉV RÁCS Kft., are presented below.
1. The “traditional stair is mounted between fl ights of stairs (supported girder, bearer beams, bearer supports) with screw joint (“classical” placement). It is popular mostly in industrial envi-ronments, since the other structures connecting to the staircase are also constructed from similar sections. In this case the fl ights of stairs – beyond the considerations of strength – are selected in such a way that they should cover the stairs from side view. Its typical beam sections are hot rolled U-steel of larger cross-section (UNP), cold bent U-steel, cold bent C-section, board sheet of ap-propriate thickness. These steel beams allow sim-ilar fastening modes of other gratings of the stair-case structures (landings, exits) to the stairs. Typical forms of staircases: straight, or broken, one-, two- or multi-fl ight staircases (Fig. 36). Fig. 36: General layout
2. The stair plate is mounted onto the L- or fl at steel supports placed in the internal side of the fl ights of stairs with a fastening fi tting suitable for the bar spacing (Fig. 37). In this case the walkway grating is without a mounting plate, is supplied only with a safety entering edge (NORMAL + BB band). It is applied primarily for staircases of maximum one-storey – overlapping height. For this construction “hiding” of the stair plates is not evident behind the beams. Its typical beams: the sections mentioned in the foregoing, but being smaller, as well as the closed sections of quadruple or rectangular cross-section. For the stairs, landings same fastening is used in this case. Its typical forms of stairs: straight, one-fl ight, and drawn stair or quarter-arched staircases.
Fig. 37: Other construction
Unit run
Gratings
Fastening fi tting
Carriage
Carriage
Stair
Overlapping
Uni
t ri
se
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3. In this variation the gratings are mounted onto supports constructed properly for rising and tread-ing, placed in the middle (on the treading line) or in two sides of the staircase (Fig. 38). Its typical supports: L-steels, closed sections, hot rolled I-supports. Here the use of the NORMAL + BB band construction is also favourable by stair. Its main types of staircases: straight, one-fl ight, as well as girder and chain stairs.
Fig. 38: Other construction
4. The circular- and spiral staircases form a separate group. Their structural construction is so varied that it would be diffi cult to classify them in accordance with any considerations. As a result, their grat-ings are designed exclusively on the basis of individual requirements.
6. 10. Shelf gratings
By spread of the warehouses, industrial in-stallations, logistic centres there is an ever increasing demand for the professional stor-age of large quantities of spare parts, com-modities. The shelf gratings of NAGÉV RÁCS Kft. of different size, construction and load-ing capacity offer solutions for this. In our brochure we call your attention to the two most frequent types in accordance with keep-ing the gratings in position, their catching.
1. In the sides perpendicular to the bearing bars a frame of larger size than usual is weld-ed onto the grating (Fig. 39). The frame “over-hanging” onto the supports prevents the dis-location of the shelf grating. Fig. 39: Shelf grating with overhanging border
2. An overhanging border is also placed in parallel with the supports, but the catching is supplemented with pinched frame elements corresponding to the sizes of the supports (Fig. 40).
Fig. 40: Shelf grating with pinched frame
Overhanging frame
Overhanging frame
Pinched frame
Frame
Support
Support
Gratings
Fastening fi ttingCarriage
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6.11. L-steel framed gratings
In the otherwise varied world of forms of the walkway gratings the grating products framed with L-steel mean a newer patch of colour (Fig. 41). The main characteristic of the construction is the border of “L” cross-section fi tting perpendicularly onto the bearing bars, which is also responsible for the transfer of load. For strength, produc-tion technology and aesthetic reasons it is worth selecting such hot rolled symmetri-cal or asymmetrical angle steels, in case of which the length of their leg connected to the bearing bars corresponds to the height of the bearing bars. The gratings supplied with such a frame are also suitable to cov-er shelf systems, but we can meet them as a drain grating or air gratings built in per-pendicularly. Fig. 41: L-bordered gratings
Support Frame
L-border
Designing Aid
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7. Surface ProtectionThe products manufactured by NAGÉV RÁCS Kft. are supplied with surface protection of the quality meeting the customer’s requirements. The primary objective of the protection is the preservation of the structural material against the corrosive impacts of the atmosphere. The most advanced technologies are offered to our customers in accordance with what corrosion and other requirements are raised against the products.
7.1. Hot-dip galvanizing
The NAGÉV group has own hot-dip galvanizing plants. At the site in Tiszacsege and that handed over in Ócsa in 2011 the Technigalva(R) process is applied. The main point of the method is that protective layer is formed in such a metal bath of a special zinc-nickel (Zn-Ni) alloy, on the effect of which the coats – also in case of steel qualities of some unfavourable chemical com-position – will be economical and aesthetic. The so-formed surface complies with the strictest requirements included in the MSZ EN ISO 1461 standard.In Hungary the so-called passivation can be utilized exclusively in one place – in the hot-dip galvanizing plant of NAGÉV CINK Kft. in Ócsa –, which means the special subsequent treatment of the freshly hot-dip galvanized products. As a result of the process such an acryl layer is formed on the surface of the product, which preserves the aesthetic brightness of the zinc layer for months and prevents the forma-tion of white rust for a year. The protective coat of our products – arising from their excellent corrosion properties – provides a long service life and maintenance-free operation for decades. The specifi cations of MSZ EN ISO 14713, ISO 9223 provide information on the corrosion service life of the zinc (Table 15).
The basin dimensions of our hot-dip galvanizing plants (Fig. 42/A and 42/B):
Tiszacsege
Length: 7200 mm Width: 1050 mmDepth: 2400 mm
Fig. 42/A: The useful sizes of the hot-dip galvanizing plant in Tiszacsege
Material thickness [mm]
Average thickness of the zinc layer
(minimum value) [μm]
1,5 ≤ v ≤ 3 55
3 < v ≤ 6 70
v >6 85
Corrosivity category Corrosion load Average corrosion rate (μm/year)
Internal space: dry Very little ≤ 0,1
Internal space: occasionally vapour con-densation; External space: rural inner
area standing freely Little 0,1-0,7
Internal space: high humidity, medium air pollution; External space: inner-city
area, or slight coast Medium 0,7-2
Internal space: swimming pools, chemi-cal plants, etc. External space: industrial
inner area, or urban coastLarge 2-4
External space: industrial area with high humidity or coast with high salt content Very large 4-8
Seawater in temperate zone areas Very large 10-20
Table 14: Coat thickness in accordance with Table 3 of MSZ EN ISO 1461:2009
1050 mm
7200 mm
2400
mm
Table 15: The corrosion service life of the zinc (EN ISO 14713)
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Ócsa
Length: 15 000 mm Width: 1 800 mmDepth: 3 000 mm
Fig. 42/B: The useful sizes of the hot-dip galvanizing plant in Ócsa
7.2. Painting
If the corrosion circumstances allow or the aesthetic expectations require, the steel surface is provided with an electrostatically powder-sprayed plastic coat instead of a zinc coat. Our products are supplied in the colour (on the basis of the RAL colour chart and surface quality (bright, matt, silky or nacreous) as per our customers’ demand. For the selection of the coat type suitable for the corrosion load the MSZ EN ISO 12944-4 standard provides assistance.
7.3. Duplex protection
For extremely large corrosion load the hot-dip galvanized surface is provided with a further plastic layer (duplex coat). In such cases after hot-dip galvanizing – particularly taking care of the cleanness of the zinc coat – we apply a plastic coat suitable for the zinc surface in a colour and quality meeting the customer’s requirements. Upon selection of the coat type it is practical to take the requirements of the MSZ EN ISO 12944-3 standard into consideration.The protective layer produced by electrostatic powder-spraying is solid and pore-free, so it provides excellent protection for the zinc layer under it, and the zinc protects the plastic cover against peeling (synergy-effect).
8. PricingNAGÉV RÁCS Kft. calculates the unit price of the walkway grating on the basis of the size of the tread. Further size- and shape fees may be charged to the unit price, which are determined by classifi cation in accordance with Table 16.
Table 16: Size- and shape groups
As it can be seen from the foregoings, it is recommended to plan the largest rate of NORMAL walkway gratings of 0.71-2 m2 for cost-saving.
Size ranges
I. < 0,15 m2
II. 0,16-0,3 m2
III. 0,31-0,5 m2
IV. 0,51-0,7 m2
V. 0,71-2 m2
VI. 2 m2 >
Shape groups
I. Normal
II. Square S
III. Square C
IV. Profi le S
V. Profi le C
VI. Breakthrough S
VII. Breakthrough C
1800 mm
15 000 mm
3000
mm
Designing Aid
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9. Inquiry, OrderYour demand for the walkway grating can be forwarded to us by fax, electronic mail or by post, but personal contact is also possible through our sales representative.The certifi cates available in the homepage of the NAGÉV group provide assistance for making the inquiry. Your letter of inquiry fi lled in with the data of the necessary walkway gratings can be sent on-line or you can select the downloadable Demand Recording Sheet, which can be forwarded to us by fax later on. In case of companies the precondition for sending a quotation is the receipt of its tax number, by which our customers are identifi ed in our internally used company management system.Fig. 43 also helps you with identifi cation of the products included in the certifi cates. We refer to the inquiry with the proposal number (e.g. 12345A), whereas to the order we refer with the job number (e.g. HB12.1234).
Make Shape designation Bar spacingSign of the grating Tread Grating type Size of the bearing bar Surface protection Size of the crossbar Type of the frame element Fig. 43: Quotation sample (the prices indicated in the fi gure is only for demonstration)
The following features shall be determined for making a proposal (but at least upon ordering):- cross-sectional sizes of the bearing bar- cross-sectional sizes of the crossbar (in a basic case it depends on the production technology)- type of the frame element- sizes of the bar spacing- construction of the thread- overall dimensions and shape designation- quantities- raw material quality- surface protection- intended use of the walkway gratings- additional fi ttings
We have indicated earlier that that we refer to the size of bearing bar direction with the fi rst dimension fi gure. For textual description (without any drawing) it is worth indicating the size of the side parallel with the bearing bar with bold numbers, or by underlining (e.g. 850 x 1000, or 1200 x 900).If the walkway grating is not rectangular or square (NORMAL) shaped, i.e. cannot be described clearly with the H x L overall dimensions and/or contains any accessory, an agreed, clear drawing documenta-tion is required to be attached to the order in any case.
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10. Related ServicesNAGÉV RÁCS Kft. is at its customers’ disposal with the following services in addition to the manufac-ture of the varied grating products – by adjusting itself to the market demands.
10.1. Consultation
In order that our partners can own the product being the most suitable for them, our experienced colleagues are readily at our customers’ disposal by phone, e-mail or personally.
10.2. On-site survey
In case of an order our colleagues – after preliminary agreement – carry out an on-site survey for con-structing the products and making the sizes more accurate.
10.3. Designing
For the appropriate and economical walkway grating selection, division, construction and installation our colleagues make the most optimal implementation plans for you by means of modern designing software.
10.4. The manufacture of other structures
Besides those mentioned in the foregoing, we undertake the manufacture of smaller steel structures connecting to the gratings as well.
10.5. Delivery
Vehicles of different sizes and load-bearing capacities are available in the NAGÉV group to satisfy the transport demands. The grating products of lower weight and size are delivered to our customers through collaboration of companies specialized in collective transportation.
10.6. Assembly
Upon separate order we undertake the installation, building-in of the products manufactured by us as necessary.
10.7. Stocks
For the faster service NAGÉV RÁCS Kft. has warehouse stocks from walkway- and board gratings, stairs of certain types, sizes, as well as all versions of the fastening fi ttings.
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11. Certifi cationsNAGÉV RÁCS Kft. puts great emphasis on the implementation of its environmental- and quality policy. Our aim is that the name of NAGÉV RÁCS Kft. means the same as the quality- and environment-conscious grating production.
For this we introduced the quality- and environment-centred management systems as per the MSZ EN ISO 9001:2008, MSZ EN ISO 14001:2004 standards, which were certifi ed by SGS Hungária Kft.
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Notes
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Designing Aid
www.nagev.hu
Contact NAGÉV RÁCS Kft.4220 Hajdúböszörmény, Kinizsi u. 5.Tel.: +36-52-563-113Fax.: +36-52-563-178E-mail: nagev.racs@nagev.huGPS coordinate: North 47°4’ 43.78” and East 21°32’ 04.59”
Year of publication: 2012 (revised edition)
NAGÉV