Flexibility on 5 axis universal machining centre

Story added 11 April 2012.

The dihedral angles formed by the surfaces of two planes from -15 to +105 deg can now be machined using a single axis of a Reiden five-axis universal machining centre following the development by Reiden, the Swiss machine tool builder, of a trigonal milling head.

Fitted to the latest Reiden RX18, five-axis universal machining centre now marketed in the UK by 2D CNC of Rusden Northants, the trigonal head design used in the horizontal spindle position ensures that both the X- and Y-axes are continuously loaded in the same direction to significantly reduce any influence and inaccuracies caused by cross-stressing on the component.

In addition, combined milling and turning operations can be performed on components up to 2,600 mm diameter by 1,610 mm high. As the turning cycle is initiated, the main spindle is pneumatically clamped and the rotary worktable turned through a gearless drive at up to 250 revs/min.

The Reiden RX18 is a heavy duty machine which is constructed around a Hydropol® composite steel/concrete mix for the machine bed and column which together weigh some 12 tonnes. The X-axis is 2,200 mm (1,800 mm when the trigonal milling head is fitted) the Y-axis is 2,200 mm and Z-axis is 1,610 mm. The C-axis rotary table is 1,800 mm diameter and the maximum table loading eight tonnes.

Controlled by Heidenhain iTNC 530 HSCI or Siemens 840 DSI DND units, the HSK 100-A taper spindle is available with three levels of power to suit the application. As standard the 8,000 revs/min spindle has a 102 kW drive that develops 557 Nm of torque while the 15,000 revs/min option spindle is powered by a 73 kW motor which has 348 Nm of torque available. Meanwhile, for high speed production cycles a 20,000 revs/min spindle variant has 187 kW of power and 102 Nm of torque. Rapid feed rates are 40 m/min in X, Y and Z axes.

The trigone head uses a worm drive that repositions from vertical to horizontal positions within one second. In the horizontal position the spindle centre line can be driven 10 mm below the edge of the table with the advantage of using maximum stability from the table face in the set up without the need for fixturing.
Linear measuring scales are integrated into the spindle head and a ‘smart-vision’ camera-based system is available to monitor the machining process with the viewing screen mounted above the control system console.

Attention to ergonomics means the machine has been developed for operator ease of use with a large viewing window and easy access to the work area via a 2,300 mm gap created in the slide-aside guarding. This also maximises access to the table for loading/unloading by crane.

Tool capacity is 104 positions as standard with options for the magazine to hold up to 400 tools each 125 mm dia (250 mm adjacent pockets left empty) and 600 mm in length. Coolant supply is 30 bar as standard while 50 and 80 bar supplies are optional. Four chip conveyors are integrated into the machine frame to ensure effective swarf removal and the benefits accrued from thermal efficiency.
 
Due to the RX18’s modular construction design by Reiden engineers, two, three or four pallets 1,800 mm by 1,400 mm can be integrated into the production process with further options of a linear pallet storage system. Pallets are located using four zero-point clamping with a repeatability of ±0.01 mm.