In the corrugated cardboard industry – on corrugators – and paper and converting industries – on cutters, unwinders, etc – roll stands can be equipped with mechanical chucks or expanding shafts and with pneumatic brakes.

How to select the suitable pneumatic brake for your roll stand

Brakes are mounted on roll stands and unwinders within closed or open web tension control systems.

They are used together with tension control systems to adjust the torque in order to always obtain the web tension required and to guarantee a high quality final product.

Pneumatic brakes must maintain an accurate and constant web tensioning at any line speed and in emergency stop situations.

How to select the suitable pneumatic brake to your application?

UNIT OF MEASUREMENT:

  • T max: Maximum web tension [N]
  • T min: Minimum web tension [N]
  • Ts: Web tension per centimeter [N/cm]
  • D max: Maximum roll diameter [m]
  • D min: Minimum roll diameter [m]
  • L max: Maximum web width [cm]
  • L min: Minimum web width [cm]
  • m: Roll maximum weight [kg]
  • v: Web speed [m/min]
  • p: Heat dissipated [kW]
  • t: Breaking time [s]

SPECIFIC TENSION VALUES FOR MATERIAL

Paper

Weight g/m2103060100150200
Web tension [N] per centimeter Ts0,312,53,244,8

Other materials

Cellophane (N/cm for µ of thickness)0,042
Polyethylene (N/cm for µ of thickness)0,02
Polypropylene (N/cm for µ of thickness)0,025
Aluminum (N/cm for µ of thickness)0,025

USEFUL FORMULAS

Roll inertia
Minimun/maximum revolutions per minute
Web speed

WEB TENSIONING

Calculation example:

How to select the suitable pneumatic brake for your roll stand
  • Paper Weight = 150 gr/m²
  • Dmax = 1,8 m
  • Dmin = 0,17 m
  • Lmax = 220 cm
  • Lmin = 100 cm
  • v = 240 m/min
  • m = 3500 kg
Maximum web tension
Minimum web tension
Maximum torque
Minimum torque
Heat dissipated
Minimum avarage rounds per minute

EMERGENCY STOP

Torque

RECOMMENDED BRAKE = TURBOREX TX HD 180.120

Multidisc brake with double fan. The Turborex, pioneer of eco-friendly brakes improves the unwinding efficiency while ensuring the highest performance and the least maintenance requirements for spare parts.

Thanks to double fan ventilation, it works at lower temperatures also on the toughest applications -7/24- where working conditions are extreme and working temperatures need to be drastically dissipated (example: bridge applications).

Low operating temperatures avoid brake components overheating – which consequently causes a loss of tension coinsistency – and contribute to the consistent reduction of the pad wear and powder pollution. Turborex can fit any applications and roll stand even in its dimensions thanks to its high versatility that ensures the maximum sensitivity in every kind of production.

Maximum torque 2800 Nm, maximum heat dissipation up to 12 kW.

  • 100% interchangeable with all brakes
  • Easy and fast installation
  • 100% Plug & Play
  • Maximum sensitivity
  • Maximum heat dissipation
  • Pads RoHs compliant
  • Pads life span up to 42 000 working hours even in extreme working conditions
  • External pad wear indicator