Home » Case history » CENTRO DI LAVORO A 5 ASSI PER LAVORAZIONI  SU TELAI IN LEGA LEGGERA

5-AXIS MACHINING CENTRE TO PROCESS LIGHT ALLOY FRAMES

1.0 PURPOSE OF SUPPLY

The creation of a machining centre for milling, drilling and tapping on light alloy door and window frames for the railway sector.

The work area can be divided into 2 distinct areas for commuting operations; for each area there is a tool store.

The equipment for the staff of the work pieces is also supplied

2.0 SUPPLY COMPOSITION

The supply includes:

  • n. 1 CNC 5-axis machining centre – 3 linear axes + 2 rotating axes
  • n. 1 16KW electric spindle complete with SIEMENS command and control unit
  • n. 1 cast iron work table complete with 18 longitudinal  T slots
  • n. 24 columns for supporting the work piece
  • n. 24 pneumatic brackets
  • n. 10 clamping brackets
  • n. 1 vacuum system

3.0   TECHNICAL FEATURES

 

Speed X axis 50 m/min
Speed Y axis 50 m/min
Speed Z axis 30 m/min
Speed C axis 30 g/min
Speed A axis 36 g/min
Stoke X axis 4300 mm
Stoke Y axis 2800 mm
Stoke Z axis 900 mm
Stoke C axis ±185°
Stoke A axis ±110°
Power  X axis 10 Kw
Power  Y axis 5 Kw
Power  Z axis 5Kw
Power electric spindle 16 Kw

4.0   DESCRIPTION OF THE MACHINE

4.1 Structure and movement of linear axes

It is a portal made up of 2 closed-ring structures joined together at the top by 2 connecting beams. The width of the machine allows to obtain an area around the table of about 80 cm of width along the entire perimeter. In the lower part the portal is fixed to the floor by means of foundation bolts On the 2 upper longitudinal beams of the closed ring, the 4 sliding guides and the 2 X axes control racks are placed. This configuration – in electro-welded and normalized steel – fixed conveniently to the floor – guarantees the rigidity necessary to the robot to support the working thrusts.

The Y axis is constituted by a mobile beam that slides on the 2 upper beams of the closed ring of the fixed structure. On the Y mobile beam runs the Y-axis carriage carrying the vertical Z-axis sliding guides. The axes components are selected from our more rigid standard components to guarantee a vibration-free machining and deviations from the programmed trajectories. All linear axes are driven by brushless motors (SIEMENS) and by an O-shaped gearbox. The X and Y axes actuators are preloaded rack-and-pinion , while the Z-axis control is recirculating ball screw with double preloaded spiral. All guides of the linear X, Y and Z axes are recirculating ball bearings with preloaded skids.

4.2 Rotating axes and electric spindle movement

At the end of the vertical arm there is a head with a rotation group with 2 controlled axes: A axis and C axis. The head is a simple fork and supports the electric spindle.

The A and C axes are equipped with automatic hydraulic brakes. The electric spindle can work with variable and programmable speeds during the working cycle. The electric spindle is equipped with a droplet (evaporable) oil sprayer and air which lubricates the tool and evacuates the chip. Tools with HSK-F63 attachments are placed on a fixed 12-position rack. The tool change is achieved by moving the portal’s X, Y and Z axes.

 

4.3 Perimeter security enclosure

The work centre will be enclosed on the 3 sides with a sheet metal casing and transparent methacrylate fixed to the structure of the machine and with a front door with an opening of approximately 2.4mt to side packaging with safety sensors.

5.0 DESCRIPTION OF THE WORKING TABLE

Table in cast iron G30 dimensions 3800mm x 1800mm thickness 75mm hardness HB 190/200 free of blowing and porosity material that absorbs the vibrations and allows after appropriate treatments to get a good distension, eliminating internal tensions and ensuring excellent dimensional stability. 18 T-slots Incorporated, 3600mm long, hollow centre distance 100mm hollow dimension 18H7. The table is complete with compressed air/vacuum system with square collector placed on the 4 sides of the table (pipes, fittings, air solenoid valve, FRL group).

6.0 WORK PIECE FIXING EQUIPMENT

Work piece support column: each bracket is supported by a steel column h = 300mm for work piece support with table fixing system and predisposition for the attachment of the holding plates (suction cups)

Pneumatic pressure bracket with a movable bracket which works under pressure (for extruded)

7.0  DESCRIPTION OF THE COMMAND AND CONTROL UNIT

The electrical cabinet with command and control panel contains the control unit of the 5 controlled axes, the video, the operating programming keyboard, the logic unit, the drives for the motors and the power device. The CNC control is SIEMENS 840D type with basic graphic interface and programming in ISO language.