Cylindrical gear RPS

straight-toothedsegment teethmetal

Overview
Nexen Group’s Roller Pinion Gear System features a patented pinion with bearing-supported rollers and a proprietary tooth profile. Available configurations include full ring gears and arc segments with external or internal teeth, as well as gears pre-installed on heavy‑duty bearings to suit application requirements.

Key benefits

• High positional accuracy
• Zero backlash
• No cumulative error
• Low-velocity ripple
• High speed capability
• Rigidity
• Low noise
• Low maintenance
• Corrosion resistance
• Long life

Performance highlights
Nexen systems provide precise mechanical indexing: one-way positional accuracy down to ± 1.7 ArcSec and repeatability down to ± 0.3 ArcSec (dependent on gear and application). Roller Pinion Gear Systems support high indexing speeds and can tolerate peak torque inputs at any time, enabling shorter indexing cycles compared with many traditional solutions.

Comparison — Full Ring Gears vs Segment Gears (summary table)
Characteristic | Full Ring Gears | Segment Gears
Teeth Orientation | External or Internal | External or Internal
Gear Ratio | 3:1 to 110:1 | 2.2:1 to 170:1
Maximum Dynamic Torque | Up to 19,252 Nm [170,395 in-lb] | Up to 24,383.3 Nm [215,811 in-lb]
Nominal Torque | Up to 19,252 Nm [170,395 in-lb] | Up to 17,112.7 Nm [151,460 in-lb]
Maximum Backlash | 0 ArcSec | 0 ArcSec
One-Way Positional Accuracy | As accurate as ± 3.0 ArcSec | As accurate as ± 1.7 ArcSec
One-Way Repeatability | As accurate as ± 0.8 ArcSec | As accurate as ± 0.3 ArcSec
Maximum Velocity | Up to 1,333 RPM | Up to 546 RPM
Rotational Inertia | 0.01 to 18.6 kg·m² [0.24 to 441.8 lb·ft²] | 0.002 to 48.07 kg·m² per segment [0.048 to 1,141.81 lb·ft²]
Outer Diameter | 122 to 2,686 mm [4.80 to 105.75 in] | 408 to 7,428 mm [16.06 to 292.44 in]
Arc Segment | N/A (360° complete ring gear) | 9° to 238° (most, not all segments can create full rings)
Mounting | Pilots on I.D. (external tooth) / Pilots on O.D. (internal tooth) | Pilots on I.D. (external tooth) / Pilots on O.D. (internal tooth)
Finish | Dense Hard Chrome or Black Oxide | Dense Hard Chrome or Black Oxide

Roller Pinions (summary)
Maximum Velocity | Up to 1,820 RPM
Rotational Inertia | 0.00004 to 0.21866 kg·m² [0.00095 to 5.19382 lb·ft²]
Mounting | ISO-9409 Flange Mount (12 to 80 mm pilot) or shaft mount with locking collar (10 to 60 mm)
Finish | Dense Hard Chrome, Nickel Plated, Stainless Steel

Additional product notes
Solutions include full ring gears, arc segments with external or internal teeth, and pre-installed gears on heavy‑duty bearings. Roller Pinion Gear Systems deliver repeatable accuracy with zero backlash across long travel, operate with low noise at high speeds, and support lower maintenance with long service life.

Technical specifications

• Indexing precision: one-way positional accuracy as fine as ± 1.7 ArcSec (gear dependent)
• Repeatability: as fine as ± 0.3 ArcSec (gear dependent)
• Zero Backlash: 0 ArcSec maximum backlash
• Maximum dynamic torque (examples): Full ring up to 19,252 Nm; Segments up to 24,383.3 Nm
• Gear ratios available: Full rings 3:1–110:1; Segments 2.2:1–170:1
• Maximum velocity (examples): Full ring up to 1,333 RPM; Segment up to 546 RPM; Roller pinions up to 1,820 RPM
• Outer diameter ranges: Full rings 122–2,686 mm; Segments 408–7,428 mm
• Rotational inertia ranges: Full rings 0.01–18.6 kg·m²; Segments 0.002–48.07 kg·m² per segment
• Mounting options: Pilots on I.D. (external tooth) or O.D. (internal tooth); ISO-9409 flange or shaft mounting for pinions
• Available finishes: Dense Hard Chrome, Black Oxide, Nickel Plating, Stainless Steel