Gear rating and marine reduction gear - Nauticus Machinery - Gear Faceload and Gear Rating
Marine reduction gear analysis
Gear rating and marine reduction gear analysis
For marine reduction gears, sub-surface fatigue which commonly happens on large bevel gear (mn>16), is critical in gear rating. DNV so far is the only class society that has developed the calculation method and criteria to prevent such damages. DNV’s extensive marine gear experience over the decades has led to the development of the powerful tool for gear rating and marine reduction gear analysis.
The Nauticus Machinery gear package is divided into two tools - Gear Rating and Gear Faceload. With these tools, you can calculate contact stresses, scuffing and fatigue capacity and face load distribution in marine reduction gears. These two software can be used together or separately.
Software for marine reduction gear analysis
- The software covers gear rating as limited by contact stresses (pitting, spalling or case crushing), subsurface fatigue, tooth root stresses (fatigue breakage or overload breakage), and scuffing resistance
- Faceload calculation combines elastic deflection of pinion and gear with other linear misalignments
- Gear Rating and Gear Faceload tools share input
- Efficient determination of load-carrying capacity for gear with ice-class notation
- Faceload tool can be used as input to gear rating tool or for verification of the tooth contact patterns by lacquer test during the sea trial
- Faceload also suitable for design optimization of the helix modification
- Calculations in accordance with DNV Class Guidelines 0036 (Gear rating for marine transmissions) and 0041 (ice strengthening of propulsion machinery)
- DNV Class Guidelines 0036 is mainly based on ISO 6336 Part 1-5 (cylindrical gears), partly on ISO 10300 Part 1-3 (bevel gears) and ISO Technical Reports on Scuffing and Fatigue Damage Accumulation
- The Gear Rating tool also supports the calculation according to standards of ISO 6336 for the cylindrical gear and ISO10300 for the bevel gear
Key benefits of the Gear Faceload and Gear Rating software module
- DNV’s extensive know-how and know-why
- Visual representation and animation of gear geometry
- Graphical representation of lead modifications
- The program supports three calculation standards: DNV standard, ISO 6336 standard and ISO 10300 standard
- Flexible report generator
- Printout of the standard gear datasheet
- Calculates subsurface fatigue criteria (not in ISO)
- Enhanced method for root safety on bevel gears in marine applications
- Support for IACS Unified Requirements for Polar/Baltic ice-class
- Calculates torque loads, surface durability, tooth strength, subsurface fatigue and scuffing due to ice impacting
- Clear results and good reporting interfaces
- For cylindrical gear and bevel gear
