ANALISIS CETAKAN INJEKSI PLASTIK IMPELLER POMPA AIR PADA KAPAL NELAYAN APLIKASI CAD/CAE/CAM

Most of the fishermen in Indonesia, using pumps to drain water in the ship. The use of pumps insea water often lead to rapid corrosion, especially on the impeller. Impeller manufacture of plasticmaterials is an alternative to solve this problem. Stages in the designing mould of plastic impeller is with3D and 2D drawing, choose a suitable polymer material, making mold of product, selecting componentsof mold and simulating the result. In designing mould of plastic impeller used software to simulate theplastic mould with mould parameters plastic inserts to get the best results before the completion ofproduction. As for plastic injection machine that is used to clamp force 1000 ton capacity with 8 pieces ineach injection products and using nylon material, 281,1oC temperature parameters, 62 sec of cycle timeand 80,552 MPa pressure.

Influence of Configuration Error in Bolted Joints on Detection Error of Clamp Force Detection Method

Clamp force errors in bolted joints often cause accidents in various mechanical structures. Therefore, the clamp force must be controlled accurately and maintained for securing the reliability of mechanical structures such as vehicles. However, the clamp force cannot be controlled easily during tightening. Moreover, it is difficult to detect the clamp force after tightening. We previously proposed a method to easily detect the clamp force of a bolted joint that has been tightened. In that method, the bolt thread protruding from the nut is pulled while the nut’s upper surface is supported. The relationship between tensile force and displacement at the pulling point where the tensile force is applied differs before and after the tensile force reaches the clamp force. The method detects the tensile force at the point, where the relationship changes, as the clamp force. In this study, we investigate the influence of squareness error on the bearing surface of the clamped part in a bolted joint on the detection error of the method using experiments and finite element (FE) analysis. The experimental results show that the squareness error has an influence on the detection accuracy. The average detection error in the experiments increases by approximately 10% with an increase in the squareness error. To understand the cause of this phenomenon, we investigate the effects of backlash between mating thread surfaces of bolts and nuts on the detection error. The results show that the error decreased because of the backlash. Consequently, it is assumed that the error is caused by the non-separation of the mating thread surfaces when the tensile force reached the clamp force. Furthermore, the FE analysis results show that the squareness error on the bearing surface of the clamped part has an influence of the squareness error on the detection accuracy. The results indicate that we should control the tolerance of squareness errors on the bearing surface of the clamped part when the clamp force detection method is applied to bolted joints.

Robustness of Detection Method for Clamp Force Against Configuration Error in Bolt/Nut Assemblies

Reliability of bolt/nut assemblies directly influences the quality of machines and structures. It is most important to control and maintain the clamp force of bolt/nut assemblies to secure reliability. However it is not easy to control the clamp force during tightening. And it is also difficult to detect the clamp force after tightening. In our previous study, we proposed a method to easily detect the clamp force of bolt/nut assemblies that have already been tightened. In the method, the bolt thread portion protruding from the nut is pulled while supporting the nut’s upper surface. The relationship between the tensile force and the displacement at the pulling point differs before and after the tensile force reaches the clamp force. The method can detect the tensile force at the point where the relationship changes as the clamp force. In this study, robustness of the detection method for the squareness error of the bearing surface of clamped parts has been investigated by FE analysis and experiments. The results of the FE analysis showed that the squareness error of the bolt bearing surface does not have an influence on the detection accuracy. The results indicate that the detection method has robustness for the squareness error of bolt bearing surfaces. Contrary to that, the experimental results show that the squareness error does have a clear influence on the detection accuracy. The averages of detection error in the experiments increased about 10% with an increase in squareness error. It is considered that the error was caused because the mating thread surfaces did not separate when the tensile force reached the clamp force.