Oil Quenching -Tempered Spring Wire Performance
Oil Quenching -Tempered Spring Wire Performance, ,oil quenched alloyed spring wire application.
The valve spring is an important part of the valve assembly in the valve train of the internal combustion engine. (Oil quenching - tempering spring wire performance use) Its role is: When the valve is closed, rely on the elastic force to keep the valve and the valve seat closed and sealed; in the valve opening and closing process, so that the valve and its drive mechanism does not break away from the cam control And follow it. Valve springs are subjected to periodic alternating loads during operation and must also overcome the additional loads caused by vibrations that the mechanism may produce during high speed operation. In addition, due to the limitation of the size of the cylinder head itself, the size of the valve spring is also limited, resulting in a serious stress state.
Oil Quenching - Tempering spring wire, During engine operation, the oil quenching-tempering spring wire valve spring is not only used to ensure that the valve closes when it needs to be closed, but more importantly, it can ensure that the valve moves in accordance with the motion law determined by the profile of the distribution cam during the entire air distribution process. . In order to prevent the tappet (or rocker) from leaving the cam profile instantaneously, that is, to ensure the sealing performance of the valve, the valve spring should have sufficient rigidity so that its pressing force is always greater than the inertia force that the valve mechanism generates to disengage. However, if the spring stiffness is too large, the spring force that the related parts and components need to overcome during the valve movement is correspondingly larger. This requires increasing the strength and wear resistance of the stressed parts. The appropriate spring stiffness is chosen to help reduce noise, vibration and wear caused by valve motion. In addition, in order to meet the long-term high-speed engine operation, valve springs must also have excellent fatigue resistance.
Compared with the optimization design theory as a numerical method to solve the optimization problem, since its establishment, it has achieved extensive development in the field of industrial research and design, and has also been well applied in the research and design of internal combustion engines. This topic uses the multi-objective optimization design theory to design the valve spring, explains the application of the optimization theory in the mechanical design of the internal combustion engine, and adopts a more optimal design method, establishes the constraint condition, and selects the size of the valve spring. After analyzing the stress state and deformation through the analysis software ANSYS, the results obtained should be light weight, small size, and good anti-resonance characteristics, reduce production costs, improve product competitiveness, and reduce the bearing load and vibration of the internal combustion engine Such as, there is a certain reference value for the research and design of other mechanical parts of the internal combustion engine.
At present, the widely used spring stress and deformation calculation formula is derived from the material mechanics. Without some practical experience, it is difficult to design and manufacture high-precision springs. As the design stress increases, many previous experiences are no longer applicable. For this reason, springs must be used for precise analysis. The most widely used method is the finite element method
Finite element method is a numerical method developed with the wide application of computer in the 1960s. Has a strong versatility and flexibility. As early as the early 1940s, Euler and others proposed the basic idea of the finite element method, but it has not attracted enough attention from people. It was not until the mid-1950s that some people began to use this idea to perform matrix analysis on aircraft structures in aeronautical engineering. The analytical thinking was that the entire structure was viewed as a collection of interconnected finite element units, each formed by The combination of the mechanical properties of the unit provides the mechanical properties of the overall structure. This idea of dealing with problems was widely used in 1960 to solve plane stress problems in elastic mechanics and began to use the term “Finite Element Method”. Since then, with the rapid development of electronic computers, the finite element method has become even more impressive. After more than 40 years of development, there are many large-scale, general-purpose finite dead analytic programs available at home and abroad, such as ANSYS and ADINA. Many large-scale finite element analysis softwares are now equipped with powerful front-end processing programs, and artificial intelligence technology has been introduced into the finite element analysis software to form a more complete expert system, and the intelligence of finite element analysis has been realized. Change.
Under certain conditions, the combined structure of internal units can be approximated to the real structure, so the interpolation of sub-regions can also approach its real solution. This solution method and the conditions it satisfies are what the finite element method needs to study. The finite element method can be adapted to any complex geometric region and is convenient for dealing with different boundary conditions, which is superior to the commonly used difference method. Under certain conditions, the smaller the unit and the more nodes, the higher the accuracy of the finite element numerical solution.
The finite element method is a combination of hypothetically dividing a continuum to be analyzed into finite elements. This process is simply referred to as discretization. The difference between a discretized assembly and a real elastomer is that the connection between the unit and the unit in the assembly is not related to anything other than the node. However, this kind of connection must meet the conditions of deformation coordination, and neither cracks nor overlaps should occur. Obviously, internal forces can only be transmitted between the units through the nodes. The internal force transmitted through the node is called the node force, and the load acting on the node is called the node load. When the continuum is deformed by an external force. The elements that make up it will also be deformed, so that each node will produce a different degree of displacement. This displacement is called the displacement of the node.
In the finite element, the displacement of the node is often used as the basic unknown. For each unit, based on the idea of block approximation, suppose that a simple function approximately represents the distribution law of the displacement within the unit, and then use the variational principle or other methods in mechanics theory to establish the relationship between the node force and the node displacement. The relationship between the mechanical properties, get a set of the node displacement as an unknown amount of the algebraic equation, in order to solve the displacement component of the node. Then use the interpolation function to determine the number of displacement scenes on the unit aggregate. Obviously, if the unit meets the problem convergence requirements, then as the size of the unit is reduced and the number of units in the solution area is increased, the approximate degree of the solution will continue to improve, and the approximate solution will eventually converge to the exact solution.
For decades, the finite element method has been widely used in various engineering fields. The corresponding large-scale software has become an important and indispensable computing tool in modern engineering design. Especially in recent years, due to the increasingly widespread application of computer-aided design in engineering design, the finite element package has become one of the indispensable and important contents of a common calculation method library, and combined with the optimization design technology, has formed a large-scale Integrated system. Engineers using these systems can efficiently and reasonably determine the best design [9].
For more than 30 years, finite element analysis has been highly welcomed by the engineering community because of its high computational accuracy, wide computing power, and simple application-side computational cost, which has provided extremely successful results for various structural strength issues. At home and abroad, the optimal design of the spring still stays in the optimization of the parameters. In order to further simulate, the intuitive results are obtained. In ANSYS, constraints can be added based on actual usage, and strength and stiffness aspects can be viewed and optimized.
Although the spring finite element analysis method has been put into practical use in countries with a high level of spring technology, although China has technical development in this area, it has not yet formed a practical model.