O.ERRE.PI. / ERRE PI — Precision Grinding and Honing Machine Tools

Italian O.ERRE.PI. (ERRE PI) double face, external, internal grinding and automatic raceway honing machines engineered for bearing rings, rollers, and automated production lines.

MTD Series Double Face Grinding Machines

O.ERRE.PI. (ERRE PI) double face grinding machines series MTD 100-150, MTD 250, MTD 300, and MTD 600 grind inner and outer bearing rings. They machine both faces simultaneously for diameters of 20–460 mm and widths of 5–200 mm. Spare parts include grinding spindles, diamond dressers, and feed discs.

Models: MTD 100-150, 250, 300, 600
Workpiece OD: Ø20–460 mm
Ring width: 5–200 mm
Process: double face grinding

MTD 760 and MTD 915 Heavy Double Face Grinders

O.ERRE.PI. (ERRE PI) heavy double face grinders MTD 760 and MTD 915 perform through-feed grinding on large bearing rings. MTD 760 handles Ø85–460 mm rings, while MTD 915 machines Ø250–750 mm parts with 20–250 mm width. Service parts include spindle heads, wheel flanges, guides, and nozzles.

Models: MTD 760 and MTD 915
MTD 915 range: Ø250–750 mm
Workpiece width: 20–250 mm
Mode: through-feed face grinding

MTE Series External Cylindrical Grinding Machines

O.ERRE.PI. (ERRE PI) external grinding machines series MTE 80, MTE 130, MTE 250, MTE 420, and MTE 600 machine bearing ring outer diameters. They cover workpiece diameters of Ø10–600 mm and widths of 10–210 mm. Spare parts include wheel spindles, magnetic chucks, support shoes, and dressers.

Models: MTE 80, 130, 250, 420, 600
External diameter: Ø10–600 mm
Workpiece width: 10–210 mm
Process: OD bearing ring grinding

MTI Series CNC Internal Grinding Machines

O.ERRE.PI. (ERRE PI) CNC internal grinding machines series MTI 80, MTI 130, MTI 250, MTI 420, and MTI 600 finish bearing bores and raceways. They accept ring external diameters of Ø10–600 mm and widths of 10–210 mm. Replaceable parts include high-frequency electrospindles, quills, and dressers.

Models: MTI 80, 130, 250, 420, 600
Workpiece OD: Ø10–600 mm
Ring width: 10–210 mm
Process: ID and raceway grinding

MTH Series Automatic Raceway Honing Machines

O.ERRE.PI. (ERRE PI) automatic honing machines series MTH (MTH 150 I-SRB, 200, 250, 350, 400) superfinish bearing raceways. They process CRB, TBU, SRB, TRB, and DGBB rings across Ø20–600 mm diameters. Spare parts include oscillating honing heads, stone holders, drive rollers, and shoes.

Models: MTH 150, 200, 250, 350, 400
Bearings: CRB, TBU, SRB, TRB, DGBB
Covered range: OD Ø20–600 mm
Process: raceway superfinishing

O.ERRE.PI. Special Grinding, Honing and Tape Polishing Machines

O.ERRE.PI. (ERRE PI) special machines are built for dedicated precision finishing tasks in bearing and automotive plants. Solutions include end face grinders for tapered rollers, honing units for pump shafts and hubs, and tape polishing machines. Spare parts include polishing heads and spindles.

Tapered roller end face grinders
Pump shaft and hub honing units
Tape polishing machine modules
Vertical on-demand face grinders

O.ERRE.PI. Turnkey Bearing Ring Production Lines

O.ERRE.PI. (ERRE PI) turnkey bearing production lines have been built in Buriasco (Turin, Italy) since 1969. Integrated cells link MTD, MTE, MTI, and MTH machines into a continuous grinding and superfinishing workflow. Line modules include conveyors, washing stations, and gauging units.

Plant: Buriasco (Turin, Italy)
Machine tool heritage: since 1969
Integrated MTD, MTE, MTI, MTH cells
In-line dimensional gauging

Gantry Loaders, Demagnetizers and Wheel Balancing Units

O.ERRE.PI. (ERRE PI) automation accessories maintain unmanned ring handling and wheel stability across shifts. The lineup features Gantry Loading systems, loading robots, demagnetizers, and rotary table buffers. Conveyor systems and automatic wheel balancing units are supplied as modules.

Gantry Loading and robot cells
Through-feed ring demagnetizers
Rotary Table buffer accumulators
Automatic wheel balancing devices

MTD Series Double Face Grinding Machine Architecture

O.ERRE.PI. (ERRE PI) double face grinding machines across series MTD 100-150, MTD 250, MTD 300, MTD 600, MTD 760, and MTD 915 are engineered for simultaneous grinding of both parallel faces on inner and outer bearing rings.

The rigid, thermally stabilized frame dampens vibration during continuous through-feed machining of workpieces ranging from Ø20 to 750 mm. Ring transport through the grinding zone utilizes interchangeable rotary carrier discs or linear guide rails with variable speed drives.

Integrated diamond dressing units and closed-loop wheel wear compensation maintain tight parallelism tolerances.

External and Internal Bearing Ring Grinding on MTE and MTI Series

O.ERRE.PI. (ERRE PI) MTE external cylindrical grinders and MTI CNC internal grinding machines cover bearing ring external diameters from Ø10 to 600 mm and widths from 10 to 210 mm.

Centerless shoe workholding on magnetic chucks guarantees roundness accuracy and concentricity between outer surfaces and internal tracks.

MTI internal grinders incorporate high-frequency electrospindles and CNC interpolated axes to finish cylindrical bores, tapered seats, deep-groove ball raceways, and roller retaining ribs in a single clamping setup.

Automatic Raceway Superfinishing on MTH Honing Machines

O.ERRE.PI. (ERRE PI) MTH series automatic honing machines (MTH 150 I-SRB, MTH 200, MTH 250, MTH 350, MTH 400) perform final superfinishing of hardened and ground bearing tracks.

The platform supports cylindrical roller (CRB), tapered roller (TRB), spherical roller (SRB), tapered bearing unit (TBU), and deep groove ball bearings (DGBB) across Ø20–600 mm diameters.

Multi-stage oscillation cycles regulate workpiece rotation speed and stone contact pressure to remove amorphous grinding layers, optimize crown profile geometry, and minimize bearing acoustic noise.

Turnkey Bearing Production Lines and Gantry Automation

O.ERRE.PI. (ERRE PI) integrates MTD, MTE, MTI, and MTH machine tools into complete automated bearing ring production lines. Inter-operation material handling combines conveyor systems, rotary Table buffer accumulators, overhead Gantry Loading portals, and multi-axis loading robots.

Production lines incorporate through-feed demagnetizers, washing units, automatic wheel balancing devices, and post-process gauging stations with closed-loop CNC offset feedback for unmanned manufacturing shifts.

O.ERRE.PI. / ERRE PI and model names are trademarks of their respective owners and are used only to identify the equipment for which we source parts. SpareX is not an official dealer, distributor or representative of O.ERRE.PI. / ERRE PI and is not affiliated with the trademark owner. Origin, documents and warranty are stated for each item in the quotation.