Vol. 21 No. 1 (2006)

This paper describes the mathematical analysis concerning the influence of time record length on the magnitude error of the Frequency Response Function (FRF) using impact hammer testing. In this paper, the value of damped natural frequency is assumed to be the same with the value of positive integer multiple of the frequency resolution in response spectrum. The mathematical analysis results an equation which can be used to calculate the error value of FRF magnitude due to the finite time record length. As an illustrative example, the simulated FRF using impact hammer testing on four S-DOF…

Clinker production of a cement plant can be increased by rising clinker to kiln feed ratio-CKFR. One of the methods for increasing CKFR is by improving the separating efficiency of the top cyclone. The increase of separating efficiency of the top cyclone causes not only the increase of production, but is also followed by the lowering of specific heat consumption and percentage of ash in the coal because the exit gas from thetop cyclone is normally used for coal drying. This paper presents a simple and cheap modification of the top cyclone that has been applied in a Indonesian cement plant.…

Sintering process has proven to be a manufacturing process that can produce a mechanical part with high geometric complexity. Development of alternative sintering process is continuously conducted to find the most inexpensive process. A solution process which is called indirect pressure-less sintering were proposed in this research. Generally this process of making a mechanical part is initiated with arranging powder by deposition machine, and continued by sintering process in conventional furnace. Optimal parameters that consist of sintering temperature and holding time in this process were…

This research presents development of vibration-based crack detection method using operating deflection shape (ODS) analysis from data measured by a Laser Doppler Vibrometer (LDV). Two types of work are conducted in this research. The first work is a numerical study, while the second work is an experimental study to verify the proposed method. In the numerical study, two types of specimen are used to simulate 2-Dimensional and 3-Dimensional problems using NASTRAN code. For the 2-Dimensional model, beams with two types of crack are tested, namely center and edge cracks. For the 3-Dimensional…

High quality motorcycle sprocket with cheaper price has been achieved by giving additional processing to non original locally made sprocket such that it has an almost the same quality as the original Japanese made sprocket. The additional processing was pack carburizing which was done to the non-original sprocket, followed by quench hardening and tempering so that the quality of the non-original sprocket will be almost the same as the original sprocket. Pack carburizing was applied with active carbon as the carbon source and 10% BaCO3 as the energizer. This process was done at 950°C and one…