Drawing for illustration. Every gage is made to your size.
Made to order · ARC · Dual or Single Master
Center-Jet Air Ring Gage (ARC)
Jets at mid-width of the ring, for the best wear life on straight diameters.
- Sizes
- .061" to 7.500" (1.55 to 190.50 mm)
- Part number
ARC-[jet+class]-[material]-[size]- Example
ARC-12-C-.7500
Priced by size in the online configurator
Build & price online →- Build the part number and see the price in minutes
- Formal PDF quote emailed to you
- Dual Master or Single Master tooling
The center-jet air ring (ARC) measures shafts, pins, valve spools and turned diameters without touching them. The jets sit at mid-width of the ring, which gives the best wear life for diameters that run the full length of the ring.
Need to measure close to a shoulder? Use the shoulder-jet (ARS) or extra-close (ARX) ring.
Two jets or three?
Two opposed jets read diameter at every angle. Centerless-ground parts are often slightly three-lobed, which two jets can't see; a three-jet ring (add -3J) picks up the lobing and reads average diameter. Sizes .061″ to .183″ are made as three-jet carbide rings only.
How to order
Ring part numbers follow the same order as probes: style, jet code with clearance class (Dual Master) or spec code (Single Master), material, then size. Dual Master rings take the min/max shaft sizes and come with a 4 ft (1.22 m) hose; Single Master rings take the nominal master size, and the hose is ordered separately.
| Dual Master | Single Master | |
|---|---|---|
| Ring bore | Maximum shaft size + clearance | Nominal master size + clearance |
| Set with | Two setting discs (min and max) | One setting disc at nominal |
Turn it into a gaging station
Base stands hold the ring upright on the bench, vee guide chutes feed long parts such as valve spools straight through, and guide pins steady short parts. Each is fitted to the ring at the factory, so order it with the ring. For shafts that stay on the machine, use an air snap gage. Set the ring with master setting discs.
Full dimensions are in the air tooling catalog (PDF).
More air ring gages
Shoulder-Jet Air Ring Gage (ARS)
Jets near the leading face, to measure a diameter close to a shoulder.
Sizes: .061" to 7.500" (1.55 to 190.50 mm)
Details & pricing →Extra-Close Shoulder-Jet Air Ring Gage (ARX)
Jets as close to the ring face as possible, for diameters right against a shoulder.
Sizes: .061" to 7.500" (1.55 to 190.50 mm)
Details & pricing →