Papers by Keyword: Spring

Abstract: Compressor valve spring failure and rapid fracture occurred in a petrochemical enterprise. To find the cause of the failure, and to ensure the safe, stable, and continuous operation of the device, the failure of the spring is analyzed. In this paper, through the macro inspection, chemical composition analysis, metallographic analysis, scanning electron microscopy analysis, energy spectrum analysis, hardness analysis, and other tests, it is concluded that the main reason for the spring fracture is the fatigue fracture caused by unqualified materials. Suggestions are given to avoid similar problems in the future, and it is hoped that this failure analysis will provide valuable experience for similar failure problems in petrochemical enterprises.

Abstract: The nonlinear second-order differential eigenvalue problem describing eigenvibrations of a bar with elastically attached load is investigated. This problem has an increasing sequence of positive simple eigenvalues with limit point at infinity. The sequence of eigenvalues corresponds to a system of normalized eigenfunctions. The initial nonlinear eigenvalue problem is approximated by the quadrature finite element method on a uniform grid. The existence and accuracy of approximate solutions are studied. Investigations of the present paper can be generalized for the cases of more complicated and important problems on eigenvibrations of beams, plates and shells with elastically attached loads.

Abstract: In order to study the influence of the cross-sectional shape on the stiffness of a spring, a finite element analysis software DEFORM is used to simulate and analyze the torsion of rectangular cross-section bars. The material of the bar is TS1800 SAE9254 and the cross-section of aspect ratio (w / h) is 1.5. From literature it is known that when the rectangular section bar is twisted, the shear stress at the four corners is zero, so elliptical corners can decrease the volume and increase the stiffness with the same volume. Five levels for the long side of the elliptical corner are set as 1 to 5 mm, and 3 levels are set for the short side. Torsion of the rectangular section bars under 15 kinds of geometric designs are simulated to find the preferred cross-sectional shape design by evaluating the cross-sectional area, load, and the maximum shear stress. The objective of the design is obtaining a uniform stress distribution with a larger spring stiffness and lighter weight. The optimal cross section of the bars is established as the spring geometry, and the pre-loading processing of the spring is simulated. The required load and the maximum shear stress data are obtained. The effects of load, cross-sectional area and maximum shear stress on the springs performance are investigated.

Abstract: The paper considers the problem of nanostructured strengthening of spring steels and springs, the idea of steel nanostructured strengthening determined not only by grain sizes but also by subgrain sizes is justified. Design schemes of thermal strain nanoscale substructure patterning in spring material produced by hot and cold coiling were implemented. Patterning of nanoscale substructure was experimentally proved. Strength analyses of spring steels and springs showed the dominant effect of nanoscale substructure on spring limited life increasing not less than 10 times at cyclic fatigue tests. Spring compression at cyclic loading decreases 10 times.

Abstract: The paper purpose is to evaluate the efficiency of a new kind of suspension trim corrector based the tests on rigs an on the vehicle. The trim correction is realized by two pneumatic elements placed on the vehicle rear shock absorbers. The tests on rigs were realized on a hydropuls rig recording the force evolution with the stroke for some pneumatic pressure. Then the trim correctors were placed on the vehicle, being tested the trim evolution with the pneumatic pressure for some loaded states. Finally the tests were continued on road to evaluate their well behavior for some loaded vehicle states. All results confirmed the high efficiency of the new trim model and its well behavior on road. This reason the new trim corrector solution is in protection phase.

Abstract: Static balancing of a mechanical system can be regarded as the total or partial cancellation of the mechanical effects (force or moment) of static loads to the actuating system of it, in all configurations, respectively in a finite number of configurations, from functioning domain, under quasi-static conditions. Active balancing is taking into consideration the variation of static loads during the functioning of mechanical systems. As a consequence the active balancing requires an adaptive controlling system and a dynamic model of mechatronic system. In this article, some aspects of the active static balancing problem of mechanical systems are surveyed.

Abstract: March to May at noon control area (exposed roof) temperature of 37.56°C, test below (green roofs) surface only 24.69°C, 24.79°C room temperature on the second floor, planting mean temperature of 27.6°C, effectively prevent the roof surface temperature rise, and thus reduce the interior roof of the second temperature 12.77°C . Building extensive green roofs to cooling, mainly to reduce the building room temperature of 3.76°C;reducing air conditioning electricity consumption , accomplish cooling and energy-saving benefits.March to May at noon (12:00-13:00), ANOVA analysis of cooling efficiency, the temperature difference between the building control area as the dependent variable, compare independent variables, and found that different monitoring areas of solar radiation cooling effect,2 floor indoor cooling temperature 13.9083°C, efficiency the most significant.Roofs of buildings spring will be applied as extensive green roof in spring, creating building roof thermal comfort (24.88°C) and Auliciems (1981) estimate room comfort temperature (24.55°C) are similar, significant benefits to achieve room thermal comfort.Buildings is applied for green roofs in the spring can reduce home power consumption (reducing air conditioning systems use frequency), to energy-saving (58.17%) of the economic benefits.

Abstract: Starting from the introduction of the management of scientific research project, and then gives a detailed description based on J2EE architecture, the lightweight composite framework involving Spring, Struts and iBATIS and an iterative method is employed in project management. With a series of functions such as application, recommendation, processing, approval, assessment and management of scientific research project and so on, the system has the characteristics of easy maintenance, dynamic propagation and strong expansibility. Finally the safety of the system is discussed from two perspectives, namely its design and environment. Years’ of application in the management of scientific research project in Gansu Province has proved its good stability, fast response and high safety.

Abstract: This paper presents the Mullins effect on the laminated rubber-metal spring analytically modeled using lumped parameter system. The general form of the equation is developed to represent the multi-degree-of-freedom system for layer of embedded metal plates. The Mullins effect can be observed when a compression load is applied to the spring. It is shown that by increasing the embedded metal plate, the Mullins effect inside the rubber is reduced due to the improved stiffness in vertical direction.

Abstract: Introduces the working principle of capping machine, the defects caused by the deficiency of the actual production situation of working medium pressure covermachine and its compensation spring, redesign compensation spring, and the design, the factors should be considered in a simple discussion.