TOPICS CALENDAR BUYER'S GUIDE AGMA

Load Carrying Capacity

TECHNICAL ARTICLES | 2023-07-27

Load Capacity Evaluation of Production-Related Geometry Adjustments via STEP Import in BECAL

Bevel gears are widely used in various industrial applications, such as automotive, aerospace, and marine industries, due to their ability to transfer power between non-parallel shafts. The conventional manufacturing of bevel gears involves several time-consuming and costly processes, including gear blank preparation, gear cutting, and gear finishing. The increasing demands on gear components regarding increasing power density, reducing installation space, reducing weight, and increasing efficiency are also reflected in the design of gear components. The reduction of installation space and weight as well as the increase in power density often leads to an optimized wheel body design that interacts with the gearing in terms of load capacity and stiffness. This leads to an increase in the required geometric degrees of freedom (DOFs). Due to the resulting complex wheel body shapes and different production-related effects, production-related geometry adjustments may also be necessary. Tools for evaluating the gearing in combination with the wheel body shape and its influences nowadays form the basis for unlocking the holistic optimization potential of transmission components.

TECHNICAL ARTICLES | 2022-04-25

Tooth Root Bending Strength of Shot-Peened Gears Made of High-Purity Steels up to the VHCF Range

Standardized methods, like AGMA 2001-D04 or ISO 6336 for the calculation of the load carrying capacities of gears are intentionally conservative to ensure broad applicability in industrial practice. However, new applications and higher requirements often demand more detailed design calculations nowadays; for example: long operating lives in wind power gearboxes or fewer gear stages and higher speeds in e-mobility applications result in higher load cycles per tooth in a gearbox.

TECHNICAL ARTICLES | 2022-02-23

Effect of the ISO 6336-3:2019 Standard Update on the Specified Load Carrying Capacity Against Tooth Root Breakage of Involute Gears

A calculation-based study of different variants with regard to contact ratio and tooth root geometry to compare the results from the 2019 version of ISO 6336 to the previous version, released in 2006.

TECHNICAL ARTICLES | 2019-03-01

New Consideration of Non-Metallic Inclusions Calculating Local Tooth Root Load Carrying Capacity of High-Strength, High-Quality Steel Gears

The effects of non-metallic inclusions in steel matrix on tooth root strength based on theoretical approach of Murakami.

TECHNICAL ARTICLES | 2018-08-01

Influences of the Residual Stress Condition on the Load-Carrying Capacity of Case-Hardened Gears

Highly loaded gears are usually casehardened to fulfill the high demands on the load-carrying capacity. Several factors, such as material, heat treatment, or macro and micro geometry, can influence the load-carrying capacity. Furthermore, the residual stress condition also significantly influences load-carrying capacity. The residual stress state results from heat treatment and can be further modified by manufacturing processes post heat treatment, e.g. grinding or shot peening.

GEAR TALK WITH CHUCK | 2018-01-16

The Company You Keep

Learning about gears is much easier in a group setting. Anyone who suffered through a tough high school or university class without study buddies w...

TECHNICAL ARTICLES | 2017-11-01

Influence of the Defect Size on the Tooth Root Load Carrying Capacity

The objective of this work is to introduce a method for the calculation of the tooth root load carrying capacity for gears, under consideration of the influence of the defect size on the endurance fatigue strength of the tooth root. The theoretical basis of this method is presented in this paper as well as the validation in running tests of helical and beveloid gears with different material batches, regarding the size distribution of inclusions. The torque level for a 50 percent failure probability of the gears is evaluated on the test rig and then compared to the results of the simulation. The simulative method allows for a performance of the staircase method that is usually performed physically in the back-to-back tests for endurance strength, as the statistical influence of the material properties is considered in the calculation model. The comparison between simulation and tests shows a high level of accordance.

TECHNICAL ARTICLES | 2017-05-01

Inclusion-Based Bending Strength Calculation of Gears

Reduced component weight and ever-increasing power density require a gear design on the border area of material capacity. In order to exploit the potential offered by modern construction materials, calculation methods for component strength must rely on a deeper understanding of fracture and material mechanics in contrast to empirical-analytical approaches.

TECHNICAL ARTICLES | 2016-09-01

Increased Tooth Bending Strength and Pitting Load Capacity of Fine-Module Gears

The common calculation methods according to DIN 3990 and ISO 6336 are based on a comparison of occurring stress and allowable stress. The influence of gear size on the load-carrying capacity is considered with the size factors YX (tooth root bending) and ZX (pitting), but there are further influences, which should be considered. In the following, major influences of gear size on the load factors as well as on the permissible tooth root bending and contact stress will be discussed.

TECHNICAL ARTICLES | 2016-01-01

Influences on Failure Modes and Load-Carrying Capacity of Grease-Lubricated Gears

In order to properly select a grease for a particular application, a sound knowledge of the influence of different grease components and operating conditions on the lubrication supply mechanism and on different failure modes is of great benefit.

TECHNICAL ARTICLES | 2014-06-01

Calculation of Tooth Root Load Carrying Capacity of Beveloid Gears

In this paper, two developed methods of tooth root load carrying capacity calculations for beveloid gears with parallel axes are presented, in part utilizing WZL software GearGenerator and ZaKo3D. One method calculates the tooth root load-carrying capacity in an FE-based approach. For the other, analytic formulas are employed to calculate the tooth root load-carrying capacity of beveloid gears. To conclude, both methods are applied to a test gear. The methods are compared both to each other and to other tests on beveloid gears with parallel axes in test bench trials.

TECHNICAL ARTICLES | 2011-05-01

Flank Load Carrying Capacity and Power Loss Reduction by Minimized Lubrication

The objective of this study was to investigate the limits concerning possible reduction of lubricant quantity in gears that could be tolerated without detrimental effects on their load carrying capacity.

TECHNICAL ARTICLES | 2009-07-01

The Effect of Manufaturing Microgeometry Variations on the Load Distribution Factor and on Gear Contact and Root Stresses

Traditionally, gear rating procedures consider manufacturing accuracy in the application of the dynamic factor, but only indirectly through the load distribution are such errors in the calculation of stresses used in the durability and gear strength equations. This paper discusses how accuracy affects the calculation of stresses and then uses both statistical design of experiments and Monte Carlo simulation techniques to quantify the effects of different manufacturing and assembly errors on root and contact stresses.

TECHNICAL ARTICLES | 2006-07-01

Generating Interchangeable 20-Degree Spur Gear Sets with Circular Fillets to Increase Load Carrying Capacity

This article presents a new spur gear 20-degree design that works interchangeably with the standard 20-degree system and achieves increased tooth bending strength and hence load carrying capacity.

TECHNICAL ARTICLES | 2004-09-01

Surface Damage Caused by Gear Profile Grinding and its Effects on Flank Load Carrying Capacity

Instances of damage to discontinuous form ground and surface-hardened gears, especially of large scale, have recently increased. This may be attributed partly to a faulty grinding process with negative effects on the surface zones and the surface properties.

TECHNICAL ARTICLES | 2003-09-01

Local 3-D Flank Form Optimizations for Bevel Gears

Optimizing the running behavior of bevel and hypoid gears means improving both noise behavior and load carrying capacity. Since load deflections change the relative position of pinion and ring gear, the position of the contact pattern will depend on the torque. Different contact positions require local 3-D flank form optimizations for improving a gear set.