Key Engineering Materials Vol. 561

Abstract: The narrow bars on tire mold segment are used for molding the sipes on the tread, Its size is small.Its shape and location is diverse and process is complex. This article, through processing feasibility analysis of the narrow bars, combined with production practice, conducted a systematic and detailed explanations on the process of molding the narrow bars in the precision casting method for molding segment.Through analyse a number of empirical conclusions about narrow bars’ forming process which have drawn, and has proved the practicality of these methods through practice.

Abstract: The regeneration technology of scrap rubber has been studied for many years, and now it is widely used. But the regeneration mechanism is still not being reached. So far, there is no theory for regeneration mechanism of scrap rubber. Under this circumstance, this paper presents a deeply reached study around this issue.

Abstract: Contrast and analysis of the influence that synchronous rotor mixer’s two phase angles 90° and 180° to the mixing effect using special visco-elasticity fluid software--Polyflow. The results show that 90° phase angle rotor could promote compound mixing, and improve mixing rubber’s uniformity, and its mixing effect is better than synchronous rotor with 180° phase angle.

Abstract: In the process of rotational molding, there are two important parameters, temperatures in the rotational molding machine’s oven and in the mold. It is the crux of the evaluation about the molding efficiency and products’ quality to control the time of the temperatures to reach the top. This article puts forward to two time parameters C1, C2 to show temperatures’ change in machine’s oven and in the mold during the molding processing. Besides, these two time parameters are applied to direct the structure design of rotational molding machines and molds. Meanwhile, the theoretical analysis agrees well with the experimental data from the comparison between them. Hence, the efficacy and practicality of the two parameters are well verified.

Abstract: Spark deposition technology is a kind of important means on rubber mold surface strengthening and repair .The temperature field for 2A12 Aluminum Alloy during EDM surface strengthening is simulated and analyzed through establishing proper finite element model based on finite element software. The results show that: During the strengthening, temperature field is mainly concentrated on the surface of work-piece and has little influence on the internal of work-piece. The temperature field of the surface of work-piece has the dynamic effects, which moves with the movement of the strengthening point and becomes stable as time passes. During the strengthening, the temperature for nodes on the surface decreases slowly after rising rapidly, and the strengthening point has the highest temperature. The barrier of the insulated boundary has a great influence on the distribution of temperature.

Abstract: A 3D triangle balance contour tire model was established by using ABAQUS software as a platform. During the calculation of the model, static loading process and cornering loading process were taken into account, and the mises pressure and contact pressure distribution and the transverse stiffness performance curve of the tire were obtained. The analysis results were compared with that of the existing design. The results of the triangle balance contour tire were beneficial to optimize the structure of tire and could provide reasonable basis for predicting the performance of tire.

Abstract: Two rotor configurations were designed for the continuous plasticator in this paper. The rotor configuration, rotor speed and machine barrel temperature were set as the variable parameters in this contrast experiment. What’s more, the experimental investigation showed that, the three factors had effects on the plastication performance. When the temperature of machine barrels and extrusion dies reached and the rotor speed was at , the plastication performance of two rotor configurations was relatively better. And the rotor configuration II was better than I by synthesizing all kinds of factors.

Abstract: This article is targeted at different rotor configurations, using of laboratory experimental platform of existing small synchronous rotor of internal mixer, under consistent conditions of cooling water temperature, floating weight pressure, filling coefficient, along with the change of rotor speed, experimental study on five different rotor configurations. Through comparison of the experimental results, choose the best rotor speed, and for further experimental research to provide the optimal parameter selection basis, to ensure that the mixing performance of the mixing-molding integrative machine.

Abstract: In this paper, the 3D flow field and dynamic mixing processing in the continuous mixer with new-type rotors have been studied using finite element software package Polyflow. The influences of continuous mixer process conditions on mixing properties were analyzed by numerical simulation. The results show that the dispersion property is mainly affected by the rotational speed of rotors and the viscosity of polymer. Better dispersion property can be gained as and the viscosity increase. However, the distribution property is mainly affected by feed rate, and the distribution efficiency will reduce if feed rate is too fast.

Abstract: Experimental studies are carried out for various vulcanization processes in a 11.00 R20 S815 tire by employing variable temperature method. The temperature variation histories inside the tire are recorded and the corresponding vulcanization degrees are obtained. It is found that the variable temperature process can not only save the vulcanizing time, but also improve the tire internal vulcanization uniformity and the equipment utilization efficiency.