The Graepel-Universal spiral stair tread is available in two versions:
- for on-site welding
- with a welded step tube that can be directly attached to a stair center tube. This version complies with the DIN EN ISO 1461 standard.
The Graepel-Universal spiral staircase step is made of steel (DD 11) and is suitable for industrial use. It is designed for a uniform load of 5 kN/m² and a point load of 1.5 kN on a 200 x 200 mm area.
Spiral stair treads with a tread tube are supplied with tread bolts and screws.
The surface features holes punched upward (d = 7 mm) and downward (d = 14 mm). The open area is approximately 19%. This step features an attractive perforation pattern and offers excellent slip resistance, a large void volume, and good drainage properties. The perforated leading edge prevents slipping over the step edge.
