PROJECT NAME: Double-girder bridge crane DMD 5 t / 16,93 m

INVESTOR: Plamen Ltd.

LOCATION: Požega

YEAR OF PRODUCTION: 2013.

TECHNICAL CHARACTERISTICS:

• maximum crane capacity: 5 t
• bridge span: 16,93 m
• maximum lifting height: approx. 8,0 m
• load lifting speed (frequency reg.): 12/9/6/2.4 m/min
• hoist travel speed (frequency reg.): 20/15/10/5 m/min
• bridge travel speed (frequency reg.): 40/30/20/10 m/min

TECHNICAL DESCRIPTION:

For the needs of the investor, the company Plamen Ltd., a project was made for the installation of a double-girder bridge crane with a maximum load capacity of 5 t, a bridge span of 16,93 m and a lifting height of approx. 8 m. in companies productio hall in Požega on the existing crane tracks.

All working movements of the crane: driving the bridge, driving the hoist and lifting/lowering the load, are driven by electric motors and are controlled by frequency controls that allow easy starting and stopping with continuous acceleration or deceleration of working movements, without jerks and shocks. Also, the crane is equipped with an electronic system controlled via a PLC which in the operation of the crane ensures maximum mitigation of load oscillations when stopping the drive of a bridge or a hoist.

The crane is operated from the floor via a radio remote control unit or by means of a control panel in the control cabin which is welded to a service platform which is welded to one of the main girders. Given the conditions and frequency of operation, the crane is classified in III. drive class according to HRN M.D1.020, which roughly corresponds to group M6 according to ISO 4301/1 (or group 3m according to FEM 1.001), for mechanisms.

Double-girder bridge crane consists of:

• steel structure consisting of:
  • main girders manufactured as box girders welded from sheets with a cross section of 370 x 832 mm,
  • end carriages manufactured as box girders made of 8 mm thick sheet metal,
  • service platforms welded to the side of one main girder along its entire length,
  • control cabins welded to the service platform,
• electric driving hoist with a capacity of 5 t,
• electrical equipment.

The electrical equipment of the crane consists of:

• electric motor of lifting mechanism with brake,
• electric motors for driving a hoist,
• two electric motors for driving the bridge,
• main electrical cabinet,
• control cabinet for electromagnet and installations for power supply and control of electromagnet,
• limit switches of all drives,
• radio remote control system,
• control panel in the cabin,
• anti-sway system,
• main switches, and
• power and control cables within the crane itself.

At the ends of the crane tracks, steel bumpers are placed as safety against the crane falling off the tracks, and rubber bumpers are against stiff impact into the obstacle. In the same way, the movement of the driving hoist along the main supports of the double-girder bridge crane is limited.