29_Aug_2022Sources_Sought_External_Cylindrical_Grinder_WVA.pdf

Abbreviated Description: The machine tool covered by this Statement of Work shall be a programmable, horizontal, external, cylindrical grinding machine. This cylindrical grinding machine shall have a center to center continuous grinding capability of 7 meters (23 feet) with a minimum wheelhead cross slide travel of 15”. This cylindrical grinding machine shall be of the traveling head type with a weight capacity of 30,000 lbs. while utilizing steadies. The machine shall have an approximate footprint of 48 feet by 17 feet.

The machine shall be designed with the specific intention and purpose of grinding. Spindle designs should reflect this.

Required Mechanical Characteristics, Capacities, Feeds, and Speeds:

A. Minimum swing over table: 24” (610 mm) B. Max workpiece length: 7 meters C. Minimum weight between centers without steadies: 10,000 lbs. (9071 kg) D. Minimum weight between headstock and steady: 30,000 lbs. (13607 kg) E. Minimum cross slide travel (x axis): 400 mm (15.75”) F. Cross slide feed speed: 0.5 to 5,000 mm/min (0.02 to 196.85 in/min) G. Cross slide servo torque x axis: 1000 N-m (7,380 ftlbs) H. X axis feed speed: 0.5 to 5,000 mm/min (0.02 to 196.85 in/min) I. Saddle servo torque Z axis: 2000 N-m (14,760 ftlbs) J. Z axis movement length: 7300mm (24ft.)

K. Grinding wheel diameter maximum capacity: 760mm (29.92”) L. Z axis speed range: 0.5 to 10000 mm/min (.02 to 393.70 in/min) M. Grinding wheel width: 76 mm (3”) to 152 mm (6”) N. Grinding wheel power: 30HP (22 kW) O. Grinding wheel spindle diameter: 160 mm (6.3”) P. Grinding wheel spindle speed: Variable Speed to 1,900 rpm Q. Grinding capacity with new wheel 29.92”: 457.2mm (18”) R. Steady rest diametric capacity: 100 mm to 500 mm (3.94” to 19.68”) S. Steady rest weight capacity: 15,000 lbs.

T. Headstock spindle diameter: 240 mm (9.45”) U. Headstock power: 30HP (22 kW) V. Headstock spindle speed capacity: Variable speed to 100 rpm W. Tailstock quill diameter: 210 mm (8.27”) X. Tailstock quill travel: 300 mm (11.81”) Y. Tailstock traverse speed: 2,200 mm/min (86.61 in/min)

Coolant System: The machine shall be equipped with a coolant system with a minimum capacity of 2,000 liters (528) gallons of coolant. The coolant system shall provide a minimum volumetric flow rate of 100 liters/minute (26 gallons per minute) of coolant at 50 bar (725 psi).

The coolant system pump shall have a grinding swarf chopper/grinder on the inlet of the pump, such as the Vaughan Chopper Pump or equal to. The system shall be of the paper type with magnetic drum and have an average filtration capacity of 25 µm (0.98 µin). Start/stop of the coolant flow shall be under CNC control. In addition to CNC control, a provision for manual actuation and control of flow rate shall be provided. All components shall be floor mounted and shall not require a special foundation or pit for installation. The coolant system shall provide a means to generate a coolant flow stop condition if insufficient coolant or a loss of required coolant pressure occurs. A warning light and a message displayed on the control shall indicate this condition. The filtration unit shall be engineered so that when fully installed in accordance with OEM instructions all points subject to periodic maintenance and lubrication shall be externally accessible and the filtration unit shall be capable of being disassembled and removed without disassembling the machine itself.

The machine shall be outfitted with a Fuji Automatic Numerical Control (FANUC) as the control system with the following automatic features:

Control System Built in Automated Functions: The control system shall have the following built-in, preprogrammed/automatic functions/cycles/features which are specifically tailored to precision CNC grinding. The machine shall have all of the required sensors, peripherals, and necessary hardware in order to successfully and reliably perform the required automatic functions as described in sections 5.5.2.1 through 5.5.2.8.

Intuitive/Conversational Programming: The control system shall be equipped with special pages for parameter input by the operator to automatically create grinding programs. This conversational programming system shall allow operators to easily generate CNC programs with a series of data prompts involving part geometry, work piece material, and tooling to guide operators through the grinding process.

Wheel Head Feed Increment: The control system shall allow the operator to select the infeed increment, and shall have the option of selecting where and when the infeed shall occur to include either or both ends of the grinding head stroke.

Automatic Size Control: The control system shall allow the operator to select a required target size on the workpiece. This shall be accomplished either by selecting the desired finish diameter or by selecting the total stock removal, selectable by the operator.

Wheel Dressing or Truing Frequency: The control system shall allow the operator the ability to program the frequency of the wheel dressing and truing. Dressing and truing frequency shall be a function of the table stroke count or stock removal increments, selectable by the operator.

The control shall also incorporate the ability to program up to four wheel dresses within any single grinding cycle and to program the amount of wheel material removed at each dress.

Wheel slide compensation for change in wheel size after dressing shall also be provided. In addition, the operator shall be able to manually initiate a dressing cycle at any point in the grinding cycle without interfering with or altering the programmed frequency of remaining automatic dress within the cycle.

Straight OD Grinding Cycle: The control system shall have a “canned” cycle for straight OD grinding.

Spark Out for Finishing Operation: The control system shall have a “canned” cycle for spark out for finishing operations.

Wheel Wear Compensation: The control system shall have built in programming to automatically adjust compensation to accommodate for reduction of diameter of the grinding wheel, as well as wear of any surfaces of the grinding wheel that contact the workpiece.

Taper Correction: The control system shall have a built in feature of mechanically detecting errors in the tool path (e.g., when the machine is grinding a taper on a straight profile). The CNC control shall correct such errors using the control system through dynamically performing offset grinding.