Patriot Forge Co. CHALLENGE:
- Rough Machine Large Forgings:
- Up to 10000 lbs
- 400" (10160 mm) length
- 78" (1981 mm) diameter
- Maintain Tolerance of +/- 0.001" (0.025 mm)
- Maintain Process Integrity Amidst:
- Rapid changeover characteristics of small lot
- Just in time nature of forging business
THE ENGINEERING TECHNOLOGIES SOLUTION:
- Provide V-60 and V-80 VTLs with specific options:
- Can handle interrupted cuts while maintaining precision
- Partner with Patriot Forge to Engineer Tool and Part Probing System to Ensure that Setup Errors will not Result in Machining Downtime or Damage to Large, Expensive Workpieces
RESULT:
- Hold Tolerances of +/- 0.001" (0.025 mm) on Parts with 40" (1016 mm) Diameter
- Perform Interrupted Cuts of 0.300" (7.6 mm) Deep at Feed Rates of 0.045 IPR (1.143 mm/rev) [Greater using Large 3/4" (19 mm) and 1" (25.4 mm) IC Inserts]
- Tool and Part Probe System Provides Confirmation of Setup Parameters
Quantum Leaps...
In Productive Machining of Large, Tough Forgings
Patriot Forge Co., Brantford, Ontario, produces custom-forged components for advanced manufacturing applications. The forgings weigh from 10 lbs. to 40,000 lbs. and include shafts up to 400" long and disks and rings up to 78" in diameter. Forged materials range from steels and stainless steels to high temperature alloys, titanium, and other specialty alloys. The forgings are used in power generation compressors and turbines as well as many other demanding industrial and military applications.
Patriot Forge also offers value-added services including rough and near-finish machining. When turning large parts, vertical lathes simplify part loading and fixturing; Patriot Forge's VTLs include one V-80 and two V-60 machines from Engineering Technologies.
The machines were built-to-order to permit turning of large forgings while maintaining tight tolerances. Rough machining at Patriot Forge can involve interrupted cuts on the order of 0.300" deep and feed rates of 0.045" ipr or heavier. At the same time, +/- 0.001" tolerances are typical. The facility first employed a V-60 to machine 40"-dia. parts to tolerances of +/- 0.003". When a customer requested +/- 0.001" precision, the machine held it easily and consistently maintained that level of tolerance on much larger parts as well.
In collaboration with Engineering Technologies design engineers, Patriot Forge specified a tool and part probing system for its V-80 VTL to prevent crashes resulting from erroneous manual entry of tool offsets. Effective in that regard, the system is also being considered as a means to speed throughput. The probe will acquire dimensional information to eliminate the time and effort spent measuring parts with hand micrometers.
Machining large rough forgings to high precision represents one of the most difficult challenges in manufacturing. Patriot Forge overcomes that challenge through the strength, precision, and consistent performance of VTLs from Engineering Technologies.