cover
Contact Name
-
Contact Email
-
Phone
-
Journal Mail Official
-
Editorial Address
-
Location
Kota surabaya,
Jawa timur
INDONESIA
IJOCE (International Journal of Offshore and Coastal Engineering)
ISSN : -     EISSN : 25800914     DOI : -
Core Subject : Engineering,
IJOCE, International Journal of Offshore and Coastal Engineering, is an academic journal on the issues related to offshore, coastal and ship science, engineering and technology. Published quarterly in February, May, August, and November.
Arjuna Subject : -
Articles 92 Documents
The Study of Mooring Buoy Operability to Support Offloading Operation of Shuttle Tankers with Various Capacities Mochammad Afif Zahiru Fajar; Eko Budi Djatmiko; Murdjito Murdjito
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 4, No 1 (2020)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i1.8704

Abstract

This study was conducted to analyse of the operability of mooring buoy initially designed for offloading operation of 35,000 DWT shuttle tankers enhanced to serve the offloading operations of shuttle tankers with 50,000 DWT, 75,000 DWT, and 111,000 DWT capacities. Operability is reviewed in term of mooring line tensions induced by each new variation of tanker capacity under environmental conditions of 1-year, 10-year, and 100-year recurrence. The governing criteria is that the safety factor should meet the appropriate limit as stated in the API RP2SK. Tension on the mooring line increases in parallel with the increasing of tanker capacity. For the case of 35,000 DWT and 50,000 DWT shuttle tankers the operation can be performed in all environmental conditions. For the case of 75,000 DWT shuttle tanker with full load and 67% DWT capacity can fully operate in all environmental conditions, but with 47% DWT capacity could not be operated in the 100-year environmental condition with significant wave height 3.31 m for the direction of inline-L1, inline-L2, and between line-L1&L4. For the case of 111,000 DWT shuttle tanker at all capacity conditions can fully operate in the 1-year environmental condition with significant wave height up to 1.48 m.
Fatigue Life Comparison of Modified and Conventional 3 Leg Jacket Offshore Structure Muhammad Nabil Ghiffary; Murdjito Murdjito; Rudi Walujo Prastianto
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 4, No 2 (2020)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i2.9306

Abstract

The jacket structure must be adapted to the conditions of the production field to support economic factors. So, the concept of a modular platform for minimal, low-cost facilities is adopted. However, the design differences will affect the performance of the jacket itself, in other words a modular jacket can withstand the same load as a conventional jacket model but has a different structural performance. Therefore, this research discusses the performance comparison, which includes the fatigue life and the natural period, between conventional and modular jacket structures, which in this study are referred to as modified jackets. Conventional jacket as a comparison structure takes the design basis of the modified structure, including the same structural profiles, and environmental loads. In this study, the two jackets will only be modeled on the jacket part and the superstructure will be modeled as a joint load on the three upper ends of the jacket legs. Fatigue life analysis in this study used the full spectral analysis method. By using SACS software, the natural period of modified jacket is 1.756 s and conventional jacket is 1.472 s. While the lowest fatigue life on modified jacket is 44.98 years and conventional jacket is 9125.79 years.
Experimental and Numerical Study on Roll Damping Structure of Floating Crane Catamaran in Free Floating and Moored Conditions Muhamad Fadkhurrohman Aziz; Eko Budi Djatmiko; Murdjito Murdjito; Baharuddin Ali
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 4, No 2 (2020)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i2.9341

Abstract

This research discusses the experimental study of free decay test This research discusses related to the experimental study of free decay test motion roll on the catamaran floating crane structure which is reviewed from free-floating and moored conditions. Experiments were conducted on the facilities of Maneuvering and Ocean Engineering Basin owned by the BTH – BPPT. The structure used as an experiment was a model of the catamaran floating crane with a scale of 1:36. The test is carried out with a horizontal mooring link system Taken from mooring system modelling, spring stiffness is used as a reference for mooring rope stiffness in numerical analysis. The analysis carried out in this final project is to compare the experimental results of the decay test with the results of the analysis using Moses software. From the results of the experiments obtained a comparison of free-floating conditions to tethered to decay tests of 38%, 8%, and 9% for linear damping values, then 93%, 12%, and 13% for quadratic damping values. Comparison of experiment results to numerical results found a difference of 128.39% for decay test 1 for quadratic damping value, then in decay test 2 and decay test 3 against the numerical got difference of 60.80% and 66.83% in linear damping value.
Analysis of Influence of Abrasive Material Variation and Spray Pressure Variation in Coating Epoxy of Astm A36 Steel Toward Impact Resistance and Corrosion Rate Herman Pratikno; Bima Satriya Willy Harsa; Sholihin Sholihin
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 4, No 2 (2020)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i2.9337

Abstract

Corrosion is a decrease in material quality caused by environmental influences. One of the methods commonly used to control corrosion is coating. In the coating process, the use of spray is the better method compared to roll and brush. Before coating is applied, the choice of abrasive material during the sand blasting process can determine the success of the coating. This research was conducted to analyze the effect of variations in abrasive material and spray pressure on the coating process of ASTM A36 steel material on its impact resistance, corrosion rate, and adhesion forces. Variation of abrasive material used were steel grit and silica. The spray pressure variations used were 2.5, 3.5, and 4.5 bar. The result of corrosion rate testing on variation with steel grit abrasive material and spray pressure of 4.5 bar has the lowest corrosion rate, with the value of 0.00124 mm/a. The highest adhesion strength test result of 9.07 MPa was obtained from variations with steel grit abrasive material and spray pressure of 4.5 bar. Impact test result using a variation with steel grit abrasive materials and a spray pressure of 4.5 bar yield the highest value, with the value of 2.287 joules.
Analysis of Pipe Lay Barge Hafar Neptune Capability in Pipelaying Operation at Offshore North West Java Oil and Gas Field Ignasius Krisna Armanda; Eko Budi Djatmiko; Imam Rochani
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 4, No 2 (2020)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i2.9338

Abstract

When pipelaying activity is carried out, the most influential factor is the significant wave height. In this final project, the maximum significant wave height allowed for the PLB during the pipelaying process was analyzed with the variation of pipe diameters, which are 8 inches, 10 inches, and 12 inches; variations in the direction of coming waves namely 0o, 45o, 90o, 135o, and 180o; and stinger angle variations. First, static analysis was performed using OFFPIPE software Then, Pipe Lay Barge (PLB) Hafar Neptune modelled with MOSES software and validated with ABS MODU codes. The output was RAO from the Hafar Neptune PLB. Next, dynamic analysis was performed with OFFPIPE software, where the input is static analysis, RAO of Pipe Lay Barge Hafar Neptune, and JONSWAP wave spectrum formulation. The result of the analysis was the significant wave height that could hit the PLB when pipelaying is 3 meters for all pipe diameter variations. For variations in the direction of the wave data, the maximum Hs were 3 meters for 0 ° and 180 °, 2.5 meters for 45 °, 1.5 meters for 90 ° and 135 °.
The Effect Analysis of Coating Thickness Variation and Mixture Composition of Magnesium – Flake Glass on Epoxy Coating on Abrasive Resistance, Adhesion Strength, and Prediction of Corrosion Rate of ASTM A36 Steel Plate Herman Pratikno; Yudiardana Tridantoko Susarno; Hasan Ikhwani
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 4, No 2 (2020)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i2.9339

Abstract

Steel cannot be separated from the marine manufacturing industry. It is important to control the corrosion rate of steel used for offshore structures. The coating method can be used in mobilization areas and splash zones that have high corrosion rates due to sustained friction loads in the marine environment. The purpose of this study was to analyze the different in adhesion strength, abrasion resistance, and corrosion rate prediction of ASTM A36 low carbon steel plate with coating thickness variations of 300µm, 500µm, and 700µm and Magnesium Carbonate - Flake Glass mixture variations of 10%, 20%, and 30%. In the pull-off test, the highest value of adhesion strength was obtained from specimen with 300µm coating thickness and 10% Magnesium Carbonate - Flake Glass mixture with a value of 5.67 Mpa. The highest abrasion test value was obtained from specimen with 700µm coating thickness and 30% Magnesium Carbonate - Flake Glass mixture with a value of 0.91 Wear Cyces per Micrometer. Whereas in the three cells electrode test, the highest value was found at specimen with 700µm coating thickness and 30% Magnesium Carbonate - Flake Glass mixture with a value of 0,00010 mmpy.
Pipe Stacking Optimization and Sea Fastening Analysis of Linepipe Transport Carlo Jonathan Sihombing; Daniel Mohammad Rosyid; Raditya Danu Riyanto
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 4, No 2 (2020)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i2.9340

Abstract

Subsea pipeline is a system comprised of multiple linepipes that are welded when installed on location used to distribute fluid such as oil and natural gas. Fabricated linepipes are to be stacked on cargo barge and transported to the installation location. This operation takes significant time and involves numerous linepipes. Optimization needs to be done to make sure the transport operation is executed efficiently. Optimization attempt was done using data from Double Joint Linepipe Transport Operation of Tangguh Expansion Project by Saipem Indonesia. Parameters considered during the optimization process include linepipe qualities during stacking, cargo barge strength and stability, and sea fastening property strength. Roark’s Formulas for Stress and Strain formulas are used in pipe stacking analysis to find stacking limit for each type of linepipes. Stability analysis is done by using DNVGL-ST-N001 as a guide and Maxsurf software for modelling. SACS software is used to analyzed sea fastening properties with guidance from DNVGL-ST-N001. Finally, optimization is done using a multi-criteria optimization method by using values from each analysis as parameters. Optimization results find that pipe stacking method using side support is 8.41% more optimal than standard pipe stacking method from Saipem Indonesia.
Analysis of the Effect of Abrasive Material and Polyurethane Coating Thickness Variations on ASTM A36 Steel Towards Corrosion Rate in Sea Water Environment Herman Pratikno; Felita Widya Hapsari; Wimala Lalitya Dhanista
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 5, No 1 (2021)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i3.9953

Abstract

An unavoidable phenomenon of using steel as the main material in offshore structures and floating vessels is corrosion. One method of preventing corrosion is by coating and using polyurethane is one type of coating that is currently being developed in the maritime industry. But the success of this coating process is very dependent on the surface preparation process. The usual method used is blasting using an abrasive material. This study aims to find the response to the corrosion rate of polyurethane coating with thickness variations of 60 µm, 80 µm, and 100 µm by first blasting using abrasive material variations in the form of silica sand and steel grit. The result of the corrosion rate test showed that the lowest corrosion rate value was obtained in the variation of abrasive material in the form of steel grit. with a 100. µm of polyurethane coating thickness, that is 0,00008 mm/a. While the highest corrosion rate value was obtained in the variation of abrasive material in the form of silica sand with a 60 µm of polyurethane coating thickness, that is 0,02202 mm/a. 
Influence Analysis of Shielding Gas Flow Rate and Purity Level Variation on GMAW Welding Process to Microstructure of Alumunium 5083 Nur Syahroni; Sadewa Sechan Winando; Yeyes Mulyadi
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 5, No 1 (2021)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i3.9954

Abstract

Aluminium is a commonly used material in construction and transportation industries. The advantages of using the aluminium material are its light weight, corrosion resistant, and the capability to form an alloy with another metal. Therefore, the aim of this research is to analyze the influence of shielding gas flow rate and purity level variation to mechanical properties and microstructure of the welded material. The welding process used on this research was the GMAW method. The material used was aluminium 5083 series with 300 mm x 150 mm x 8 mm dimensions. The shielding gases used were high purity (HP) and ultra-high purity (UHP) argon (Ar). The variations of shielding gas flow rate used were 16, 18, dan 20 litre/minutes. Based on the tensile test that has been done, the variation of UHP argon gas with 20 litre/minute flow rate had the best result with yield strength of 217,32 MPa and ultimate strength of 295,83 MPa. The result of the micro photos showed that the GMAW method produced small dots where the dots were Mg2Si formation, which the greater number of smaller size dot produced would increase the mechanical properties of  the material.
The Effect Analysis of Coating Thickness Variation and Mixture Composition of Magnesium – Flake Glass on Epoxy Coating on Abrasive Resistance, Adhesion Strength, and Prediction of Corrosion Rate of ASTM A36 Steel Plate Herman Pratikno; Yudiardana Tridantoko Susarno; Hasan Ikhwani
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 5, No 1 (2021)
Publisher : DRPM (Direktorat Riset dan Pengabdian kepada Masyarakat) ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j2580-0914.v4i3.9956

Abstract

Steel cannot be separated from the marine manufacturing industry. It is important to control the corrosion rate of steel used for offshore structures. The coating method can be used in mobilization areas and splash zones that have high corrosion rates due to sustained friction loads in the marine environment. The purpose of this study was to analyze the different in adhesion strength, abrasion resistance, and corrosion rate prediction of ASTM A36 low carbon steel plate with coating thickness variations of 300µm, 500µm, and 700µm and Magnesium Carbonate - Flake Glass mixture variations of 10%, 20%, and 30%. In the pull-off test, the highest value of adhesion strength was obtained from specimen with 300µm coating thickness and 10% Magnesium Carbonate - Flake Glass mixture with a value of 5.67 Mpa. The highest abrasion test value was obtained from specimen with 700µm coating thickness and 30% Magnesium Carbonate - Flake Glass mixture with a value of 0.91 Wear Cyces per Micrometer. Whereas in the three cells electrode test, the highest value was found at specimen with 700µm coating thickness and 30% Magnesium Carbonate - Flake Glass mixture with a value of 0,00010 mmpy.

Page 3 of 10 | Total Record : 92