Audited Supplier
1. external steel stairs- metal stair treads
We manufacture different styles of stair ladders that used in family,industry and construction.
Material: mill steel black and hot dip Galvanizing / and stainless grating
Usage: ladder, flooring walkway, platform ,steel structures, stair tread, well cover, trench cover, sump cover,compound gratings, storage shelves,fences and handrail so on for construction project, oil project, seaport, power plant, water plant, defense project, chemical factory and so on.
2 metal stair treads type.
1)There are six kinds of steel grating stair T1,T2,T3,T4.T5,T6
T1 Welded fixing and Without nosing
T2 Bolted fixing and without nosing,easy to installation and dismantle
T3 Welded fixing and with checkered plate nosing, can be anti-skid.
T4 Bolted fxing and with checkered plate nosing, can be anti-skid ,easy be installation,
T5 Welded fixing and with striped plate nosing, can be anti-skid.
T6 Bolted fixing and with striped plate nosing, can be anti-skid.
2) Material: Mild Steel (Low Carbon Steel) or Stainless Steel
3) Surface Treatment:
Untreated, Painting ,Powder coated or Hot dip Galvanizing
4) Steel grating standards:
A) China: YB/T4001-1998
B) USA: ANSI/NAAMM (MBG531-88)
C) UK: BS4592-1987
D) Australia: AS1657-1988
E) Japan: JJS
Pitch of Bearing bar | Cross-bar Pitch | Specification of bearing bar load(width×thickness) | |||||
32×5 | 40×5 | 45×5 | 50×5 | 55×5 | 60×5 | ||
30 | 100 | G325/30/100 | G405/30/100 | G455/30/100 | G505/30/100 | G555/30/100 | G605/30/100 |
50 | G325/30/50 | G405/30/50 | G455/30/50 | G505/30/50 | G555/30/50 | G605/30/50 | |
40 | 100 | G325/40/100 | G405/40/100 | G455/40/100 | G505/40/100 | G555/40/100 | G605/40/100 |
50 | G325/40/50 | G405/40/50 | G455/40/50 | G505/40/50 | G555/40/50 | G605/40/50 | |
60 | 50 | G325/60/50 | G405/60/50 | G455/60/50 | G505/60/50 | G555/60/50 | G605/60/50 |
Max. Stair treads lengths
Steel grating specification Bearing bar size | 25*3 | 25*5 | 32*5 |
Bearing bar pitch30mm | 550 | 900 | 1300 |
Bearing bar pitch 40mm | 450 | 750 | 1200 |
Recommend stair tread widths
T1,T2,T3,T4 Bearing bar pitch 30mm | 95 | 125 | 155 | 185 | 215 | 245 | 275 |
T1,T2,T3,T4 Bearing bar pitch 40mm |
| 125 | 165 |
| 205 | 245 | 285 |
| 115 | 155 |
| 195 | 235 | 275 | |
Fixing hole centers | 45 | 75 | 100 | 150 | |||
Note:bearing bar thickness 5mm
