Safety lifting brakes can be divided into two categories :
- Safety disk brakes
- Safety drum brakes
Special safety disc brake
Special disc brake, designed as lever assembly, consists of the own body of brake, jaws with brake lining, springs assembly, lever system, linear hydraulic motor and sensing unit of brake condition (Brakes on – Brakes off).
The brake is a part of independent emergency brake system (NBS). It works as a safety component of the hoisting unit on the principle of monitoring of the immediate state and behaviour mainly of the rope drum and further important components of NBS and early evaluation of occurrence of the dangerous condition of the observed parameters with the subsequent putting brakes into operation.
The braking moment is created by means of springs, that ensure braking – in hydraulic circuit there is no pressure. The releasing of the brakes is solved by means of hydraulic motor. Also in the case of electric power failure, damage or loss of pressure in hydraulic system, there always occur the automatic braking of rope drum motion. NBS system or its further proved variants of solution are (by their parameters and also dimensions) very suitable also for additional installation on already operating cranes, handling mainly molten metal and radioactive materials, travel over expensive technology, etc.
Radical decrease of risk of material damages and mainly the decisive increase of work safety is unambiguous.