Design of preform for bevel gear rotary rolling deformation
Due to the eccentric load on the workpiece during rotary forging, the metal flow is uneven. If the preform is […]
Due to the eccentric load on the workpiece during rotary forging, the metal flow is uneven. If the preform is […]
The transmission gear of heavy equipment used in the bending fatigue test is designed based on the gear applied in
Among the key areas of China’s planning, marine engineering is the most important project and development field. Marine engineering includes
The so-called “thick piece” revolving body means that the thickness h is greater than or equal to the radius R
The test adopts the form of single tooth loading. It is necessary to design special fixtures according to the standard
The stress ratio r = 0.6, the number of cycles n corresponding to the stress intensity factor at the crack
The essence of swing rolling is a special two roll rolling. In the process of rotary forging, although the swing
In order to verify the correctness of the above crack propagation, the crack length and crack tip stress intensity factor
The cold rotary forging precision forming process of bevel gear is an advanced manufacturing technology. Its process design in actual
The equivalent stress at the crack tip under different crack inclination angles is extracted and plotted, and the equivalent stress
Hypothetical generating wheel is usually used to explain the machining process of bevel gear. It is a virtual bevel gear
The dynamic continuous growth of fatigue crack is realized by resetting the crack length each time. In the numerical simulation
Study the crack propagation law when the initial crack position H0 is 60mm, 62mm, 64mm, 66mm, 68mm and 70mm respectively,
Fig. 1 shows 150, 300, 500 and 1000 times SEM images of fatigue fracture in the instantaneous fracture zone. The
In the actual process of gear meshing, the maximum contact stress usually acts on the tooth surface of the pinion.
Under the continuous loading of cyclic loading and unloading, the slip band around the crack tip deforms, resulting in the
Hypoid gear is a bevel gear with central axis offset. The tooth surface surface of this type of gear is
At 3 000 n · The equivalent time-varying meshing parameters of hypoid gear in one cycle are calculated according to
The transmission error curves obtained by finite element method and classical TCA method are compared to verify the correctness of
In order to simulate the singularity and discontinuity of element displacement stress, it is realized by constructing the extended functions
According to the established contact fatigue finite element simulation model of hypoid gear transmission system, the finite element simulation software
It can be seen that the fracture clearly presents three regions with different morphological characteristics, as shown in Figure 1.
In recent years, the machining of mechanical parts is developing in the direction of intelligence and efficiency. With the increasing
The morphological characteristics of fracture reflect the quality of materials and play an important role in material quality inspection, fault
Under the influence of crack shape, the change of mode I stress intensity factor is studied. In the process of
The transmission system of shearer cutting part has the advantages of compact structure and high bearing capacity, and can realize
Under the action of cyclic load, cracks begin to appear and grow, and the remaining life of the sample is
Under the set parameters, the gear model is simulated. As shown in the figure, the trend distribution of stress intensity
By referring to the national standard GB / t6398-2000 test method for fatigue crack growth rate of metallic materials, the
The modeling module of ABAQUS software can effectively establish three-dimensional models, but most of them are suitable for three-dimensional model
(1) Present situation In the aspect of gear profile, because the involute gear has the advantages of convenient machining and
The fatigue crack evolution test and numerical simulation of transmission gears of heavy equipment are studied. The preparation of compact
The characteristics of crack propagation under the influence of external force factors are as follows: 1) The crack surface is
ABAQUS / FE-SAFE is used for joint simulation. The analysis process is as follows: firstly, the fatigue analysis software FE-SAFE
According to the formula, the relationship between LA and FA can be used to change any shape. The machining mechanism
The transmission gear of heavy equipment has low rotation speed in the process of transmission operation, but needs to bear
Through verification, 40 test data under 5 load levels meet the requirements of lognormal distribution. Therefore, the distribution function f
J. Kmmberger proposed that it is necessary to carry out anti fatigue design for mechanical components bearing periodic load. Therefore,
In the 1960s, the Washington Museum exhibited the model of ancient Chinese guide car. According to archaeological evidence, this guide
According to the differences of loading methods, structural types and working modes of gear test devices, they can be divided
Robert Basan proposed a mathematical model of slip line contact and a multiaxial fatigue life calculation model based on Fatemi
The main form of gear failure is bending fatigue failure. According to the failure physical stress intensity model, it is
He Xiaohua of Chongqing University analyzed and studied the bending fatigue strength of 20CrMoH gear. Combined with mathematical statistics theory
The forging process of gear blank can be divided into upsetting stage, full step transition stage and extrusion flash stage.
As an important index of engineering fracture analysis, stress intensity factor is adopted by most scholars. The proposal of stress
In the traditional technology, gear processing should go through the processes of blank heat treatment, gear blank processing, tooth profile
At present, most gear forging enterprises are facing the dual pressure of increasing labor cost and difficult recruitment. The traditional
At present, the research of gear bending fatigue reliability test mainly focuses on how to improve the bearing capacity of
Multiply both sides of Paris formula by Da and integrate to obtain the formula: By substituting the stress ratio r
The research on the method of compound mode crack propagation is mainly through numerical simulation and experimental research. For the
Comparing the solid line and dotted line in Figure 1, for the same material, the value of plane stress under
Yang carried out a series of fatigue tests on C45 steel samples with local surface cracks. The effects of carburizing
In order to improve the material utilization, the forging of driven spiral bevel gear is generally realized by final forging
As the carrier of simulation calculation, grid plays a decisive role in the quality of simulation results. The selection of
Driven spiral bevel gear plays an important role in automobile rear axle reducer and is an important part of reducer.
Due to the importance of small fatigue cracks, many researchers at home and abroad have carried out extensive research on
When the tractor gear has defects, in the process of meshing transmission, the defects will have an impact on the
1) Define the ultimate load and maximum fatigue load The sample is fixed on the fixture by two round pins.
Different types of cracks have their own stress and displacement: type 1 crack is subjected to tensile stress perpendicular to
The whole fatigue process includes three stages: crack initiation, crack propagation and fracture failure caused by final instability propagation. The