1. Construction Features

The RXO and RXV gear units conform to the Renard Ra20 series for dimensions and transmission ratios, enabling versatile mounting and applications. The casing is split with bolted covers for maintenance. Gears are helical spur and Gleason bevel types, case hardened and ground for precision, low noise, and efficiency (0.91–0.95). Materials comply with UNI 7846-78 standards. Load capacity follows ISO 6336, optionally verified by AGMA 2001-C95. Shafts use high-grade steels with high safety factors and international standard keyways. Bearings are tapered or self-aligning rollers sized for longevity. Casings up to size 820 are cast iron; larger sizes use welded Fe430 steel for rigidity.

2. Sound Pressure Levels (SPL)

Noise is measured at 1 m distance at 1450 rpm input speed with ±3 dB(A) tolerance. Fan cooling adds +2 dB(A) per fan. Adjustments for other speeds are provided. Reduced noise versions are available. SPL varies by size and gear ratio, detailed in tables.

3. Gear Unit Selection Criteria

Selection depends on the service factor (Fs), which accounts for operating conditions, daily hours, starts per hour, and reliability. Fs can be assigned or calculated as Fs = fs × fv × fGa, where fs is duration factor, fv is start factor, and fGa is reliability factor. Catalog ratings assume Fs=1; for speed multipliers, multiply Fs by 1.1. Tables provide Fs values by prime mover type and load shock severity.

4. Application Sectors

Applications include agitators, alimentary machinery, winches, paper mills, chemical industry, compressors, dredges, building machinery, elevators, cranes, wood processing, machine tools, mixers, earth moving machinery, pumps, conveyors, water treatment, and fans. Each sector details equipment types and load characteristics.

5. Reliability and Service Factors

Reliability factor (fGa) ranges from 1 (normal) to 1.4 (high reliability) depending on maintenance difficulty and safety needs. Service factor (fS) adjusts for frequent starts or high starting torque via correction factor (fV) based on starts per hour and application type (U, M, S).

6. Performance Correction Factors

Input speed correction factor (fN) adjusts power and torque ratings for speeds above 1450 min⁻¹. Tables specify values by speed and gear ratio.

7. Selection Procedure

• Determine gear ratio (i = n1/n2).
• Calculate required power/torque with corrections: fn × PN ≥ P1 × fS × fV × fGa or fn × TN ≥ T2 × fS × fV × fGa.
• Select stages, size, shaft arrangement, and design.
• Verify dimensions and accessory compatibility.
• Assume 0.98 efficiency per stage in calculations.

8. Verification Checks

• Check dimensional compatibility and shaft end fittings.
• Confirm gear ratio compatibility with hollow shafts.
• Ensure radial (Fr1, Fr2) and axial loads do not exceed permissible values.
• Verify maximum overload conditions (Tmax ≤ 2 × TN) considering dynamic effects.
• Check maximum input speed against specifications.

9. Thermal Power Verification

For continuous or heavy intermittent loads in high-temperature or poor cooling environments, verify that nominal thermal power (PtN) multiplied by correction factors (fm, fa, fd, fp, ff) exceeds absorbed power. If not, upgrade cooling with heat exchangers. Calculate additional thermal power (Pta) and verify with water (fw) and air (fc) temperature factors.

10. Lubrication and Speed Limits

Maximum input speeds depend on gearbox model and lubrication method (splash or forced). Tables specify limits; some values available on request.

11. Thermal Power and Cooling Requirements

Correction factors defined as:

• PtN: Thermal power rating for open environments.
• fm: Mounting position factor (1 if forced lubrication or n1 ≤ 749 min⁻¹).
• fa: Altitude factor (decreases with altitude).
• fd: Operation time factor (increases as duty cycle decreases).
• fp: Ambient temperature factor.
• ff: Fan cooling factor (for speeds ≥ 700 min⁻¹ and specific fan types).
• fw: Water temperature factor for water-oil heat exchangers.
• fc: Air temperature factor for air-oil heat exchangers.

Tables provide values for these factors based on conditions.

12. Shaft Arrangements and Compatibility

Graphical codes and compatibility tables define shaft arrangements (e.g., A, B, ABU, C1, C2), input/output configurations, fan options, and backstops, ensuring mechanical and thermal integration.

13. Electric Motor Designation and Integration

Geared motor applications require specifying motor designation per the "Electronic Line" catalog, matching motor shaft arrangements, reduction ratios, and mounting positions with gear units.

14. Housing Materials and Options

Housing materials include steel, spheroidal cast iron, and engineering cast iron, depending on size and type. Options include reinforced output bearings for heavy-duty use, flange bearings, and special output shaft ends.

15. Critical Recommendations and Limitations

• Verify thermal power ratings with all correction factors before selecting cooling.
• Use heat exchangers if fan cooling is insufficient.
• Fan cooling factors apply only for speeds ≥ 700 min⁻¹ and specific fan types.
• Consult factory for confined space or poor ventilation applications.
• Ensure shaft arrangement compatibility to avoid mechanical conflicts.
• Specify electric motor data when ordering geared motors.

16. Flange Bearing Configurations

Various flange bearing arrangements at output shaft ends include hollow shafts and shrink disc options, mainly for RXO2 and RXO3 models. Configurations include right/left hollow shaft with flange bearing (SCS), flange bearing with shrink disc (SUS), and combinations with shrink disc provisions (SBD, SBS). Additional options available on request.

17. Lubrication

Oils are categorized as mineral, PAO synthetic, and polyglycol (PG) synthetic. Selection depends on load, duty, and temperature:

• Mineral oils: moderate loads, intermittent duty, stable temperatures.
• PAO synthetics: heavy loads, continuous duty, high temperatures.
• PG synthetics: high sliding friction applications (e.g., worm gears), but require caution due to incompatibility and water miscibility.

Food-grade oils are available for food industry applications.

Oil Viscosity and Lubrication Systems

Viscosity grades (ISO VG) recommended based on input speed and power, with forced lubrication preferred for higher power/lower speed. Viscosity ranges from ISO VG 68 to 680 depending on conditions.

Oil Change Intervals and Temperature

Synthetic oils allow longer intervals than mineral oils. Typical operating temperatures considered are 65°C, 80°C, and 90°C.

Oil Manufacturer Recommendations

Comparative tables list products from major manufacturers (AGIP, ARAL, BP, CASTROL, CHEVRON, ESSO, KLÜBER, MOBIL, OPTIMOL, Q8, SHELL, TEXACO, TOTAL, TRIBOL), including food-grade synthetics.

18. Lubricant Quantities and Mounting Positions

Lubricant volumes vary by gear unit size (802 to 830), series (RXO1, RXO2, RXO3, RXV1, RXV2, RXV3), and mounting position (M1 to M6), ranging from ~2.5 L to over 950 L. Users must follow gear unit level marks and agree on any plug arrangement deviations.

19. Upper Bearing Lubrication

Forced lubrication of upper bearings is linked to forced gear lubrication when required, ensuring adequate lubrication under heavy loads.

20. Mounting Positions

Multiple mounting positions (M1 to M6) are defined with graphical representations; alternatives detailed elsewhere.

21. Critical Notes and Recommendations

• Select oil type based on load, duty cycle, and temperature.
• Use polyglycol oils cautiously due to incompatibility and water miscibility.
• Follow manufacturer oil recommendations.
• Ensure lubricant quantities match level markings.
• Consult input/output and accessories sections for options.

22. Radial Load Correction Factors and Load Location

Correction coefficients (A, B, C) adjust permissible radial loads (Fr1 input shaft, Fr2 output shaft) based on load application distance from shaft shoulder. Formulas calculate adjusted radial loads (Fr1', Fr2'). Maximum radial loads are rated at 0.5 shaft projection distance with Fs=1.

23. Overhung and Thrust Load Verification

Procedures verify radial and axial loads on shafts due to prime movers or driven machines. Approximate formulas estimate radial loads for friction wheels, belts, gears, chains. Winch drum rope winding recommendations minimize load severity.

• Case A: For radial loads < 0.25 × Fr', axial load must be < 0.2 × Fr'.
• Case B: For radial loads > 0.25 × Fr', either quick check or full calculation with detailed data is required.

Technical support is advised for complex verifications.

24. RXO1 Gear Unit Ratings

Detailed tables provide gear ratios, output speeds, rated power (kW), torque (kNm), permissible radial loads (kN) at input speeds 1450, 1000, 500 min⁻¹, and thermal power limits without cooling. Data supports selection based on operational needs.

25. Critical Information and Best Practices

• Adjust radial load capacities with correction factors for load location.
• Verify combined radial and axial loads carefully.
• Use approximate formulas for preliminary checks; full calculations for critical cases.
• Follow recommended rope winding on winches.
• Consult rating tables to ensure compliance with power, torque, and load requirements.

26. RXO2 and RXO3 Gear Unit Ratings Overview

Data includes power ratings, torque, speeds, and thermal power limits without cooling. RXO2 units range ~20–79 kW power and 102–445 kW thermal limits; RXO3 units range ~13–72 kW power and 14–77 kW thermal limits. Hollow output shafts unavailable for some ratios (marked *).

27. RXO3 and RXV3 Gear Unit Ratings and Compatibility

Thermal power ratings up to ~20 kW without cooling. Gear ratios range from ~1 to over 600. Nominal torque up to several hundred kNm. IEC motor compatibility covers frame sizes 71 to 355. Moments of inertia range from 0.0001 to >2.6 kg·m², critical for dynamic design.

28. Shaft Dimensions, Moments of Inertia, and Standards

Detailed shaft dimensions with ISO tolerance classes (h11, H7, j6, k6, m6) and keyway sizes are provided. IEC standard shaft diameters from 28 mm to 180 mm and mounting bolt sizes (M8 to M20) ensure compatibility. Weights range from ~80 kg to over 13,500 kg depending on size.

29. Summary and Recommendations

• Use provided moments of inertia for dynamic calculations.
• Ensure shaft and keyway dimensions comply with ISO and IEC standards.
• Consider weight and size for installation and handling.
• Consult manufacturer for custom or optional configurations.

This document is a comprehensive technical reference for RXO and RXV series gear units, covering construction, performance, selection criteria, lubrication, thermal management, shaft arrangements, and detailed dimensional data to support engineering design and application.