Single, 25 hp, CAT 50 integrally-motorized spindle replaces two belt-driven spindles.
Single, 25 hp, CAT 50 integrally-motorized spindle replaces two belt-driven spindles.
Application
A major aircraft engine manufacturer wanted to upgrade to the spindle on its OM-3 and OM-4 Sundstand Omnimills (5-axis machining centers with a 150 degree tilting head). Material being machined was inconel, titanuim and other aerospace alloys.
Challenge
Converting the original two-spindle arrangement (a lowspeed spindle to handle large tools and a high-speed spindle for small tools) presented a number of challenges. A conventional rebuild would require a completely new slide casting together with a twospeed, timing, belt-coupled spindle cartridge requiring oil-bath bearing lubrication, a complicated design that would be both hard to adjust and maintain.
Solutions
Instead of redesigning the head to accommodatea conventional belt-driven spindle, the machine builder suggested an integrally-motorized spindle for better functionality. Ultimately, the solution came in the form of a single 25 hp (18.6 kW) spindle, capable of 7,500 RPM, with CAT 50 taper and through-spindle coolant. A stock spindle being unavailable, a Gilman engineering team visited the rebuilder to review the application. After research, the engineers recommened Indramat windings to fit within the severe space constraints of the head. A new head casting configuration, machined to allow coolant to circulate around the spindle body, allowed the spindle to drop into the housing and bolt through a flange, making spindle removal an under-30-minute job. To eliminate the problem of a hose band moving with the tilt head, the housing is also innerdrilled and plumbed to handle all hydraulic, coolant, and electrical requirements.
Spindle:
Motor:
Redesigning and rebuilding the user approximately one half the cost of a new machine. Six machines have been converted to date.
Total project time, from initial consultation to spindle delivery, was 18 weeks.