DN Staff

October 27, 2010

4 Min Read
Gear/Gearbox Optimization Software

Excel-Lent contains three sections - design, analysis and gear dimensions. Any ofthe sections can be used individually to run calculations. On a typical job,according to Excel Gear, hundreds of hours typically spent doing thecalculations can be saved.

The three sections are detailedbelow:

The design section calculates the size ofgears, based on minimal input by the user. The user needs to specify only theinput rotational speed, gear ratio, power to be transmitted and the materialand heat treatments selected from the material tables of all commonly usedmaterials in the industry.

Key values calculated are thediameter and face width of the pinion required to achieve the surface fatiguepower rating and optimized DP or module (based on the calculated diameter)required for the bending fatigue power rating. The data is automaticallyexported to the analysis program for detailed analysis. The results are the powerratings for 5,000 -100,000 hours of B1 life (reliability factor of 1).

If required, other values such as facewidth or center distance may be entered but Excel Gear recommends leaving the facewidth and center distance values blank for optimized gear design. Design andanalysis programs are used to design one gear stage in sequence on an external orinternal spur and helical gear mesh.

The analysis program calculates thepower rating of a gear set for 5,000, 10,000, 25,000, 50,000 and 100,000 hoursof B1 life (reliability factor of 1). Reliability factor of 1, 1.25, or 1.5 canbe selected, as required. The user needs to input mesh type (spur, helical,internal and external), pressure angle, helix angle (if applicable), pinionspeed, number of teeth in pinion and gear, material (fromthe list provided in the software), face width, DP or module and qualityrequired. Crown and/or profile shift, if used, can also be entered. The programwill calculate the power rating of the gear set and show HP or KW capabilityalong with torque, tangential force and static capacity. Static capacity isbased on yield strength and, if bending stress exceeds yield strength at anytime, permanent deformation or even tooth breakage may occur. If the resultsare satisfactory, the user can print the single page results only or,optionally, also print all the AGMA factors used in making the calculations.

The Excel-Lent software program lists commonly used gear material for the user to select.If the results are not as required, the user can select another material or changeother design criteria as required to achieve the desired results. If a special materialis desired, its yield, bending and contact stress numbers can be easily entered.If any of the required input data are missing, the program will prompt the userto supply what is missing. Metric or inch units can also be selected with justone click.

In the opinion of the manufacturer,this Excel-Lent gear dimension software is the most versatile program availablein the market. The program will calculate the manufacturing dimensions for a newpinion and gear or calculate the dimension of a pinion or gear to mate anexisting pinion or gear. This can be done for external gears, internal gears ora gear rack. Users need only to enter the type of mesh (spur or helical, internalof external), pressure angle, helix angle(if helical gears), number of teeth inpinion and mating gear, DP or module and the quality of the gears.

The program will then calculate thecenter distance, dimension over pins, span measurement, form diameter, rollangles and all gear tolerances to match the quality required (AGMA, DIN, orISO). The program will calculate the helix angle required to match a specifiedcenter distance if the user chooses that option.

The program displays plain Englisherror messages when input is questionable or in error. For example, if thecenter distance is incorrect, the program will flash error messages such as, "Centerdistance specified is too large/small."

The program calculates optimizedprofile shifts for pinion and gear operating at a non-standard center distance,if the operating center distance is specified. If the profile shift required tooperate is large and makes the top land narrow, the program will flash warningmessages and display the proper profile shift amount to avoid narrow top land.

Excel-Lent software gives users theoption to balance beam strength or specific sliding of gear and pinion, ifdesired. This is a key requirement for wind turbine gears. The program willalso calculate gear blank tolerances to achieve the desired quality level, ifshaft and bore diameters are entered. Users can switch between inch and metricdimensions with one click.

Sign up for the Design News Daily newsletter.

You May Also Like