Overview
A manufacturer of precision gearing and power-transmission components needed a flexible workholding system for a new high-accuracy grinding application. Working alongside a leading grinding machine OEM, Northfield developed a solution capable of handling an unusually broad range of parts while maintaining micron-level accuracy and allowing coolant to flow directly through the chuck.
Challenge
The application required one grinding platform to accommodate a wide range of O.D. and I.D. gripping requirements without sacrificing accuracy or making changeovers overly complex.
- O.D.-gripped parts ranged from 3 mm to 140 mm
- I.D.-gripped parts ranged from 6 mm to 80 mm
- Required flatness and runout ranged from 0.0001" to 0.0004"
- Pull-back action was required to maintain critical face location and flatness
- Coolant needed to flow through the chuck to flood the grinding wheels during I.D. grinding
- Multiple chucks were necessary, creating a need for fast, highly repeatable changeover
Solution
Northfield designed a five-chuck system that provided the flexibility of multiple gripping methods while using a common precision interface on the grinder.
- A Model 650, 6-inch, 3-jaw chuck with soft jaws and a roughing fixture plate accommodates the largest components and short production runs.
- A 3J collet chuck with precision collets, hard stops, and pull-back action handles O.D.-gripped parts up to 1.75 inches while positively seating each part against the locating stops.
- Three custom internal-grip collet chucks accommodate I.D.-gripped components down to 6 mm and use pull-back action to maintain consistent axial location.
- All five chucks feature coolant-through capability for direct coolant delivery during grinding.
- Northfield’s precision quick-change tapered back plates interface with a hardened and ground female adapter permanently mounted to the machine workhead.
Outcome
The finished system gives the manufacturer the flexibility to process a large family of components while maintaining the precision required for high-accuracy grinding.
- One machine can accommodate parts ranging from 3 mm O.D. to 140 mm O.D. and 6 mm I.D. to 80 mm I.D.
- Pull-back workholding provides repeatable seating for demanding flatness and runout requirements
- Coolant-through chucking supports effective wheel flooding during I.D. grinding
- Quick-change interfaces allow different chucks to be removed and replaced while maintaining 0.0001" T.I.R. repeatability
- Multiple workholding configurations provide production flexibility without sacrificing precision
The result is a highly flexible grinding system that combines quick changeover, broad part capability, and the repeatability required for demanding precision manufacturing applications.
Contact sales@northfield.com to discuss your grinding or custom workholding application.