Research Of The Large Module Gear-Rack Contact Fatigue Strength

At present, the study of large module gear rack strength becomes relatively important,and durning the big modulus gear rack transmission process, complexes contact relationshipbetween the tooth sirface often leads to large module gear failure, therefore, it has a certainsigniifcance to study the big modulus gear rack contact strength problem. And it can improvethe big modulus gear contact strength and ensure the transmission stability. But the bigmodule gear rack contact strength research lack the support of perfect theory at home andabroad. And it need to develop and choose the appropriate research methods for completingthe big modulus gear rack and contact fatigue strength calculation problems. So for the bigmodulus gear rack and contact fatigue strength calculation problems, this article main contentis as follows:First, taking big modulus gear rack designed modulus of62.7mm on the Three Gorgesship lift as the research object, through the introduction of classical Hertz theory which isused for calculating the gear and rack the contact strength, veiryf and check the feasibility ofusing ABAQUS ifnite element analysis and calculation and the accuracy of contact strengthtrial data which is obtained in the subsequent expeirment. It provides the reliable theory basisand method support for the big modulus gear rack contact strength study.Secondly，this article is based on ABAQUS to analyze large module gear rack contactstrength, and won the greatest contact stress about the static, dynamic contact and contactstress of tooth contact quench hardened layer and the stress distirbution. Compared with thecalculation result of formula, demonstrates the rationality of the boiuidary conditions and theacciracy of analysis results. The calculation result obtained from the ifnite element methodcan be used as the basis for large module gear rack strength analysis.In addition, considering the gear rack modulus is larger, there is no suitable testequipment. So this article adopts the thought "with small p”ush big commonly used inmodern design method. It is applied to study the large module gear rack and contact fatiguestrength. Through analyses the problem modulus change inlfuence gear rack contact strength,compairng with multiple sets of module gear rack and ifnite element analysis results, prove the feasibility of the test” with small push big’’.Finally, formulate the test plan "little specimen combination method" for the modulus of10mm gear, provide the conditions for obtaining regular pattern of contact fatigue strength inthe follow-up test.