Forged rolls for plate levelers

WORK ROLLS and BACK UP ROLLS for COLD and HOT PLATE LEVELERS

Up to dimensions of: Ø400 x 7000 mm max length

Since the establishment in 1967, BSA has developed and selected specific mechanical and heat treatment methodes in order to improve the quality of production and the worldwide customer service.

On the base of the experiences achieved in many years of activity BSA recommends to selest the correct grade of the steels and the relative surface hardness of rolls depending on the thermal working conditions of the levelers. This is very important because the entire heat treatment cycle of the work rolls depends on the requested final working conditions of the machines, therefore:

For temperatures of the rolled plates up to 420 °C -> follow COLD LEVELERS

For temperatures of the rolled plates higher than 420 °C -> follow HOT LEVELERS



BACK UP ROLLS for HOT and COLD PLATE LEVELERS

The back up rolls must join the characteristics of wear resistance, journal thoughness and great surface compressive strenght.
The main grades used for the production of these rolls are Chromium Molybdenum Vanaium steels, with addition of Nickel to improve the mechanical characteristics, in particular thoughness and shock resistance.



WORK ROLLS for COLD PLATE LEVELERS

The material of the work rolls for cold working operations must be very highly wear resistant and though.
This is necessary because of the high thickness of the material rolled and due to the presence of scale on the plate surfaces which is very aggressive.
For this reason to avoid an early wear of the rolling surface the induction heating process must guarantee the higher hardness reachable, without allowing any brittleness of the work roll body and surface.



WORK ROLLS for HOT PLATE LEVELERS

After the plate rolling mill the temperature of the plates is usually more than 860°C.
This means that the hot leveler receives the material at high temperature and will be subject both of mechanical and thermal stresses.
For this reason the choice of the steel grades for the rolls must mergethe characteristics of:

One relevant characteristic of these rolls is based on the heat propagation capacity in the cross section of the roll body to obtain quick cooling of the working surface; overheating can cause cracks or reduction of the hardness.

Work rolls Ø 360mm for hot plate leveler
Work rolls Ø 360mm for hot plate leveler
Material: X40CrMoV5.1 Hardened an ground


Recommended grades for back up rolls:

Material (DIN) Tensile strength (N/mm2) Recommended hardness for cold levelers Recommended hardness for hot levelers
58CrMoV4 860÷1000 58÷60 HRC //
86CrMoV7 900÷1050 58÷60 HRC 48÷52 HRC
56NiCrMoV7 950 ÷1100 56÷58 HRC 48÷52 HRC
30NiCrMoV7 860÷1000 // 46÷50 HRC


Recommended grades cold work rolls:

Material (DIN) Tensile strength (N/mm2) Recommended hardness Temperature range
58CrMoV4 860÷1000 64÷66 HRC <= 80°C
86CrMoV7 900÷1050 62÷64 HRC <= 200°C
56NiCrMoV7 950÷1100 54÷58 HRC 200°C < T < 400°C


Recommended grades hot work rolls:

Material (DIN) Tensile strength (N/mm2) Recommended hardness Temperature range
56NiCrMoV7 950÷1100 44÷48 HRC >= 550°C
X38CrMoV5.1 950÷1100 48÷52 HRC >= 550°C
X40CrMoV5.1 950÷1100 52÷56 HRC >= 550°C