Multi-Hole Flanges
Round and rectangular flanges with bolt circles, pilot diameters, and sealing faces for actuators and manifolds.
Bolt circles done right
We mill or drill PCD patterns to your angular and diametral callouts—including mixed tapped and through holes—so actuators, gearboxes, and housings line up on assembly. True-position callouts are welcome; if the print only shows a bolt circle and angle, we’ll confirm the inspection method on the quote so receiving inspection doesn’t argue with shop practice.
Pilots, registers & seals
Pilot diameters, counterbores, and O-ring grooves are machined in the same setup when practical, keeping concentricity under control. Seal faces can be flat gasket, O-ring, or face-seal style—tell us the seal part number so groove width and depth match crush, not guesswork. Masking plans for anodize/powder keep pilots at fit size after coating.
Round, rectangular & hybrid adapters
Circular motor flanges, rectangular manifold flanges, and hybrid adapter flanges that translate OEM patterns to your frame are all fair game. Matched pairs are available for sealed joints. Prototype-through-dozen batch quantities suit most export programs—send both mating patterns when you’re bridging two vendor standards.
Materials, finishes & QC
Aluminum for weight and corrosion with anodize; mild steel for cost and weldments; stainless for washdown; brass on select fluid fittings. We inspect pilots to fit class, verify PCD on critical holes, and check O-ring grooves before cosmetic finish when the sequence requires it. First-article reports available for regulated or high-reliability builds.
Where these flanges show up on RFQs
Servo motor adapters, harmonic-drive front flanges, pump and valve interfaces, pneumatic manifold ends, robot tool changers, and gearbox output plates. If a catalog flange is close but not quite, we machine the “almost OEM” version so you don’t redesign the whole housing.
Flange DFM tips
- •Give PCD, hole size, angle reference, and pilot diameter on one view—don’t bury the angle datum in a note nest.
- •If coating is required, state whether pilots are masked or opened after coat.
- •For sealed pairs, quote both flanges together and share the gasket/O-ring dash size.
PCD & pilot inspection
- ✓Pilot diameters checked to fit class when called out.
- ✓Critical PCD holes spot-checked for true position or bolt-circle accuracy.
- ✓O-ring groove width/depth verified before cosmetic coating when sequence requires it.
- ✓First-article notes available for high-reliability actuator flanges.
Lead time for flange lots
Simple aluminum flanges often follow a one-week-class prototype cadence; stainless, seal-critical pairs, and anodize/powder add time. Identical multi-cell lots get a quantity break once the first article is locked.
Flange FAQ
Can you copy an OEM motor flange?
Yes. Send the OEM drawing or a measured sample. We’ll reproduce the PCD and pilot so your spare motors drop on without re-drilling the machine.
Do you machine O-ring grooves to dash size?
Provide the dash size or groove standard on the print. We’ll cut width/depth accordingly and confirm before finish when critical.
Flange specs at a glance
- Patterns
- PCD bolt circles, rectangular grids, mixed tap/through
- Pilots
- Register OD/ID to fit class; concentric to PCD
- Sealing
- O-ring grooves, flat gasket faces, face seals
- Materials
- Aluminum, steel, stainless, brass
- Size
- Small instrument flanges to mid-size actuator plates
- Finish
- As-machined, anodize, powder, passivate, oxide
- QC
- PCD spot-check, pilot gauges, groove dims
- Batch
- 1–50+ typical; matched pairs on request
Need custom flanges?
Send PCD, hole sizes, pilot diameters, and seal details for a prototype or small-lot quote.
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