The pipeline is one of the important means necessary as the transport medium of oil and gas, so that when the pipeline leak would greatly disrupt the production process. Pipelines generally use carbon steel, a major problem in the use of carbon steel is corrosion. Therefore, there must be serious action to prevent and simultaneously tackling the corrosion. In this study, the method used to measure the rate of corrosion is LRUT, this method is the latest technology in Indonesia in the field of inspection of corrosion rate. By using ultrasonic waves, this method will detect a reduction in the thickness of the pipe (wall loss), which is then used as the primary data to calculate the corrosion rate. The following conclusions were obtained: (1) Measurement of corrosion rate by using LRUT method can detect corrosion of the inner and outer walls of the pipe, the testing process faster, efficient and more extensive inspection area when compared with conventional methods. (2) The rate of corrosion on the circuit pipelines are not the same, it is in line with the magnitude of wall loss that occurs in a series of pipelines that are influenced by internal and external factors such pipes. (3) In general, a series of pipelines that have been tested using the method LRUT have decreased performance with a reduction in the thickness of the pipe wall. The greatest reduction in thickness occurs in TP # 02, anomaly number 13 with the corrosion rate of 0237 so that the estimated remaining life at that point was 19.49 years.
Department of Mechanical Engineering, Faculty of Engineering, Universitas Riau, Indonesia.
Department of Mechanical Engineering, Sekolah Tinggi Teknologi Pekanbaru, Indonesia.
Department of Operation Engineering, Rekind Worley Parson, PT. Chevron Pacific Indonesia, Indonesia.
Aluminium alloy matrix composites attract much attention due to their lightness and moderate casting temperatures. Among the various reinforcements used in composite material, fly ash is one of the most inextensible and low density reinforcements available in large quantities as solid waste by-product obtained from combustion of coal in thermal power plants. The micro sized fly ash particles have been reduced to nano structured fly ash using High energy ball mill and the size was reduced from 53µm to 27 nm after 30 hours of milling,. Cast Al-10 wt% Mg is used as matrix to yield improved strength. Composites were fabricated with Micro and nano structured fly ash particles reinforced with Al-10Mg alloy matrix by stir casting and experiments were conducted under laboratory conditions to assess the wear characteristics of Al- 5 wt% fly ash (micro sized) and Al- 5 wt% fly ash (nano structured) composites under different working conditions in pure sliding mode on a pin-on-disc machine. The composites were given different deformations by upsetting and the effect of deformation on wear behaviour is determined in the present investigations. The wear rate of the composites was decreased with deformation and for deformations beyond 30%, the wear rate was increased due to strain softening. The increased frictional thrust at higher load results in increased debonding and caused easy removal of material and hence the wear rate is increased with increase in normal load. The coefficient of friction in all the cases is decreased with the increase of normal load. This is attributed to the wear of the matrix from the pin surface leaving the particulates standing proud.
Department of Mechanical Engineering, University College of Engineering, JNTUK, Vizianagaram -535003, India
During the period of its operation, a pressure vessel may experience excessive loading which can cause crack defects. Integrity analysis needs to be carried out to evaluate the feasibility operation of that cylindrical pressure vessel with defects. In this paper, integrity assessment of cracked pressure vessel under internal pressure and tensile residual stress was conducted based on failure assessment diagram criteria. This criteria applied widely and adopted in API 579-1/ASME FFS-1 2007 Code. There are three assessment levels provided in code. Level 1 and 2 assessment performed using analytical calculation while Level 3 assessment is conducted using finite element method. On a case study, failure criteria for the integrity analysis is based on the Failure Assessment Diagram (FAD), that distinguish safe and unsafe region based on two failure criteria, namely brittle fracture and ductile fracture. This diagram is built using finite element method with the assumptions of both Linear Elastic Fracture Mechanics (LEFM) and Elastic Plastic Fracture Mechanics (EPFM). Based on Level 1 assessment, the pressure vessel under study is not recommended to be operated, whilst based on Level 2 and 3 assessments the pressure vessel is considered acceptable. This study concludes that Level 1 and 2 analysis provide more conservative results when compared with level 3 analysis. Failure Assessment Diagram for Level 3 analysis relatively more conservative at elastic-plastic region (0.4≤Lr≤1), but less conservative at plastic collapse region. Parametric studies performed with increasing operating pressure and size of defects. Based on analysis, failures of the pressure vessel occur at pressure of 403 psi and an aspect ratio of 0.18 for analysis with including the effect of tensile residual stresses. Meanwhile, if the analysis is done by ignoring the effect of residual stress, pressure vessel failed at pressure of 589 psi and leak when aspect ratio reaching 0.42.
Mechanical Engineering, Universitas Riau, Indonesia
Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Indonesia
In Vessel Traffic System (VTS), AIS can detect a larger number of targets without considering the shadow effect and can provide more voyage information for port center. For radar system can detect target actively even buoys or rock no matter ship size or fitted equipment. But even radar can detect all targets, it is cannot give full information as AIS. AIS can give full information such as types of ship, size, name, MMSI number and etc. AIS and radar system is very important in the VTS to control ship in and out at the port area. They have to use two different computers, which is one computer for AIS and another computer is for radar systems. By integrating AIS and radar, the officer can control port with more accurate and systematic. This paper will focus on integration of AIS and Radar for managing the movement of vessels in port for safety purpose by taking Port TanjungPelepas (PTP) as a case study.
Mechanical Engineering Faculty, Universiti Teknologi Malaysia (UTM), 81310, UTM Johor Bahru
