Papers by Keyword: Interference Fit

Abstract: This paper presents the press fit calculation that depends on different methods, the sizes of holes and shafts are quantities distributed according to the normal law, so the tolerance of the joint between the shaft and the hub is also distributed according to the normal law with two parameters: the mean value and the standard deviation. The paper also demonstrates the procedure and computer program for calculating the metal interference joints given by the probability method, thereby giving a chart of choosing tolerance depending on the applied load, simultaneously calculating the interference joints by the min-max method, and comparing it with the probability method, etc. Calculation by the probability method gives more reasonable working parameters. Along with the interference fit parameters, the consideration of materials is mentioned as well.

Abstract: The contact stress field is addressed that is developed at the indenting edge of a keyless shaft-hub interference fit, in the case that both bending and shear forces are applied, and in the absence of friction. The combined effect of a set of elementary load cases is assessed for the sharp notch case in terms of a generalized stress intensity factor, with the aid of Finite Elements and for a class of shaft-hub geometries. In fact, linearity is preserved in the case of a sharp edged bore up to the incipient detachment condition; such event, which may occur as a result of e.g. excessive bending loads, may be forecast based on the proposed framework. Contact stresses in the case of rounded edge may be subsequently predicted by scaling an appropriate local solution; fatigue analysis may then be performed in the case of rotating or fluctuating loads. An exhaustive design table is finally compiled to assist the designer in dimensioning an interference fit in the presence of an arbitrary combination of time varying bending and shear forces.

Abstract: Due to obtain good mechanical properties and cost savings etc. composite roll is widely used in rolling steel industry. It is important significance for composite roll interference fit to study because assembly interference fit between roller sleeve and mandrel affect directly the performance of composite roll. In paper the calculation format of interference fit is obtained by deriving theoretically the interference fit process of composite rollers roller sleeve and mandrel. At the same time, the numerical calculation of the maximum amount of interference between roller sleeve and mandrel is done by finite element method, the results show that the theoretical calculation and finite element calculation are basically consistent, thus provide a theoretical and design for composite roll designer and has important practical value.

Abstract: To assemble easily damaged micro-parts safely in interference fit way, the assembly process is designed and the interaction force in assembly process is analyzed. The pose of micro-parts is aligned based on calibration of three microscopic vision systems from different directions. In addition, a control strategy based on feedback of vision and force is proposed to assemble safely. In the case of two micro-parts just contact, position of micro-part is adjusted based on force information to compensate pose alignment error and keep force in safe range. When micro-part is deformed as increased contact force, position of micro-part is adjusted based on force in the interference fit process and deformation of micro-part. Experimental results demonstrate the effectiveness of proposed methods.

Abstract: To improve load capacity of fabricated single-arm planetary carrier, and enlarge its applied fields, the calculation criterion of load capacity of fabricated single-arm planetary carrier under given interference amount is described according to relevant calculation theories in this paper. Some experiments have been carried out to verify the influence of different interference amounts forced on load capacity, and also the variation of force is confirmed while the planet wheel axle is pressed into the body of planetary carrier with given interference amount. The theoretical basis and reference of fabricated single-arm planetary carrier is ultimately put forward and applied in some relevant engineering practice.

Abstract: For entire roller embedded shapemeter roll, the temperature differences and radial relative displacements of contact node pairs on the interference fit surface between the framework’s top surface and roll body’s inner hole surface, and the sensor pre-pressure were analyzed using the finite element technology in cold reversible rolling passes. The influences of temperature differences on radius relative displacements of the contact node pairs and the sensor pre-pressure were obtained. The results show that the maximum temperature difference of the contact node pair occurs in the third rolling pass, and most of radial relative displacements of contact node pairs exceed the value of interference fit, which makes the sensor pre-pressure be close to zero. So the transfer of pressure that the strip applied on the outer surface of shapemeter roll is seriously affected, and the shape measuring signal is interrupted.

Abstract: Tapered interference fits can avoid the influence of keyways on the parts strength and transfer large torques. In this paper, a model was developed to study the influence of the taper on the interference fit between a propeller hub and a shaft. Using the classic elastic plane stress theory, the exact solutions of the radial stresses, tangential stresses and radial displacements of the propeller hub and shaft are derived. Then the calculation method of the magnitude of the tapered interference fit was presented. Finally taking a screw propeller system as an example, the above solutions were calculated by using the numerical method. The results show that the taper plays a key role in the interference fit. Improving the stress distribution of the propeller hub is an effective approach to increase the connection strength. The present analytical solutions are expected to be useful in the structure design of tapered interference fits for propeller hubs and shafts.

Abstract: The locomotive wheelset running with a high-speed, the wheels and axles of wheelset usually assembled by interference fit, the radial contact stress produced by interference cause the friction on the contact area, the axial force and torque of the wheelset transmitted by the friction. The value of prestress produced by the magnitude of interference change small in each load case, and it plays the main role in total stress of wheelset. So it’s very important that choosing a appropriate interference for the wheelset assembly base on the results solved by the finite element contact analysis.

Abstract: Finite element analysis has been done to analyze pump bearing assembly in interference assembly condition by ANSYS software. The press-in assembly environment has been simulated, and the maximum stress and maximum deformation of inner race have been analyzed. Studies show that with the increase of bearing size, the change law of maximum stress and maximum deformation does not single unidirectionally increase or decrease simply. At the same time, the interference value also influences the change law. So, in the bearing assembly tolerance selection the influence of the interference must be considered fully. The finite element analysis can guide the selection of fit tolerance.

Abstract: Interference-fit joining of tubes by electromagnetic forming is an innovative and environmental friendly technology that can successfully replace conventional joining technologies based on fasteners, structural adhesives, welding and brazing. The technology works at room temperature, allows joining dissimilar materials and offers potential to foster new applications in the assembly of lightweight tubular frame structures. As with all new technologies, there is a need to understand interference-fit joining of tubes by electromagnetic forming in terms of its major parameters with the aim of identifying their influence on the overall strength of the joints and establishing the useful range of process operating conditions. This article investigates the interference-fit joining of aluminum-alloy tubes (AA6082-O) with mandrels made from different metallic and polymeric materials (AA6082-O, AISI1045 and Erlaton 6SA). Results show that the strength of the joint and the associated failure mechanisms are directly related to process parameters and materials.