Slow pulling or handling and cable tensioning operations, for which the pullies are often repositioned and must be both highly resistant and extremely light, with minimum winding ratios, such as R = 5 or 6.3, since the sheaves have a low turning rate.
Lifting at speeds or frequencies that vary according to winding ratios and ISO/FEM use groups.
Pulling or tensioning operations with overloads of up to 60 % of the maximum vertical static load (WLL) for lifting operations are permissible in situations where no shock occurs when the load does not leave the ground.
Pulley with unique advantages :
- lightweight : use of "HR" steel with good anti-aging properties and resistance to cold temperatures,
- does not unhook: the apparatus opens by releasing the locked shaft and turning the plate on the sheave shaft,
- interchangeable hanging parts: alloy hook with pawl or swivel and "HR" shackle or shaft and fixed socket centred for hooking,
- for oblique returns:the "cable guide" sheave groove is designed for 6 x 36-180 kg/mm2 cables,
- does not wear out: the hub of the bronze banded sheave, fitted with a lubricating unit, is mounted on a tempered, case-hardened shaft,
- permanent lubrication: sheave on sealed bearings,
- bichromate finish.