The Experts below are selected from a list of 69 Experts worldwide ranked by ideXlab platform

Nelson Coelho - One of the best experts on this subject based on the ideXlab platform.

  • Single-Pour/Single Pass Loading: An Innovative Concept for a New Generation of Ore Carriers
    Volume 6: Ocean Engineering, 2011
    Co-Authors: Ricardo Barreto Portella, Luiza F. Andrade, Tomazo Garzia Neto, Nelson Coelho
    Abstract:

    Bulk Carriers have been developed since 1950 to carry large quantities of non-packed commodities such as grains, coal and iron Ore. Nowadays, there are some 5,000 bulk Carriers around the world and this number points to some concerns that affect owners of these types of ship and ports. One of these problems is the big waiting time at the ports that reaches 12% of the global fleet around the world at any given moment. At Brazilian iron Ore ports the time waiting average was of 6–8 days during 2006–2008. A concrete example is the VALE operation that responds from mineral resources exploration to mineral resources delivery, passing through mines, railroads, seaport terminals and shipping business, forming a logistic chain that can not be interrupted by the expected growth in trade and consequent port congestion. In view of this, PROJEMAR and VALE faced the challenge of designing Ore Carriers in such a way that it would not interfere with the logistics chain by delaying other ships at the loading or discharge terminal. As the cargo operation is taken as the initial point of the design conception, the expected final product is a ship able to safely take loading rates as high as 16,000 tons of Ore per hour, with each hold loaded in one pour and the ship fully loaded in one pass, resulting in fewer pours into the holds of the Ore carrier, faster loading operations and, consequently, a significant economy for the ship owner and for the port. The amount of extra steel needed over conventional designs: less than one percent. The fundamental idea of this new concept, which PROJEMAR calls “single-pour, single-pass” design, is a method of ballast control that is synchronized with the cargo loading, scientifically deballasting the ship during loading in a way that balances the forces induced by the incoming cargo. Potential hull loading stress problems can occur due to the manner in which Ore cargoes are loaded and due to the amount of cargo which is loaded in an individual hold. To avoid the creation of any unacceptable stresses in the ship’s structure, loading studies considering the planning of cargo loading and discharging operations, maximum allowable and minimum required mass of cargo for each hold and for adjacent holds as a function of the draught at mid-hold position in form of hold mass curves, calculations of still water shear forces and still water bending moments for each port loading condition and structural analysis are required to be developed on the early design stages. This ship loading concept is creating a new generation of Ore Carriers in such a way that the main class societies are nowadays developing new specific class notation dedicated to these ships. The purpose of this paper is to present the “single-pour, single pass” concept development and how it has been applied to the design of the new 400,000 DWT Ore Carriers that are being built for VALE in Chinese and KOrean shipyards, and to the 80,100 DWT Bauxite Carrier that are being built for LOG-IN in Brazil. The “single-pour, single pass” concept was also partially considered on the design of 12 VLCCs that are being converted to VLOCs for VALE in China with PROJEMAR’s design.Copyright © 2011 by ASME

  • single pour single pass loading an innovative concept for a new generation of Ore Carriers
    ASME 2011 30th International Conference on Ocean Offshore and Arctic Engineering, 2011
    Co-Authors: Ricardo Barreto Portella, Luiza F. Andrade, Tomazo Garzia Neto, Nelson Coelho
    Abstract:

    Bulk Carriers have been developed since 1950 to carry large quantities of non-packed commodities such as grains, coal and iron Ore. Nowadays, there are some 5,000 bulk Carriers around the world and this number points to some concerns that affect owners of these types of ship and ports. One of these problems is the big waiting time at the ports that reaches 12% of the global fleet around the world at any given moment. At Brazilian iron Ore ports the time waiting average was of 6–8 days during 2006–2008. A concrete example is the VALE operation that responds from mineral resources exploration to mineral resources delivery, passing through mines, railroads, seaport terminals and shipping business, forming a logistic chain that can not be interrupted by the expected growth in trade and consequent port congestion. In view of this, PROJEMAR and VALE faced the challenge of designing Ore Carriers in such a way that it would not interfere with the logistics chain by delaying other ships at the loading or discharge terminal. As the cargo operation is taken as the initial point of the design conception, the expected final product is a ship able to safely take loading rates as high as 16,000 tons of Ore per hour, with each hold loaded in one pour and the ship fully loaded in one pass, resulting in fewer pours into the holds of the Ore carrier, faster loading operations and, consequently, a significant economy for the ship owner and for the port. The amount of extra steel needed over conventional designs: less than one percent. The fundamental idea of this new concept, which PROJEMAR calls “single-pour, single-pass” design, is a method of ballast control that is synchronized with the cargo loading, scientifically deballasting the ship during loading in a way that balances the forces induced by the incoming cargo. Potential hull loading stress problems can occur due to the manner in which Ore cargoes are loaded and due to the amount of cargo which is loaded in an individual hold. To avoid the creation of any unacceptable stresses in the ship’s structure, loading studies considering the planning of cargo loading and discharging operations, maximum allowable and minimum required mass of cargo for each hold and for adjacent holds as a function of the draught at mid-hold position in form of hold mass curves, calculations of still water shear forces and still water bending moments for each port loading condition and structural analysis are required to be developed on the early design stages. This ship loading concept is creating a new generation of Ore Carriers in such a way that the main class societies are nowadays developing new specific class notation dedicated to these ships. The purpose of this paper is to present the “single-pour, single pass” concept development and how it has been applied to the design of the new 400,000 DWT Ore Carriers that are being built for VALE in Chinese and KOrean shipyards, and to the 80,100 DWT Bauxite Carrier that are being built for LOG-IN in Brazil. The “single-pour, single pass” concept was also partially considered on the design of 12 VLCCs that are being converted to VLOCs for VALE in China with PROJEMAR’s design.Copyright © 2011 by ASME

Ricardo Barreto Portella - One of the best experts on this subject based on the ideXlab platform.

  • Single-Pour/Single Pass Loading: An Innovative Concept for a New Generation of Ore Carriers
    Volume 6: Ocean Engineering, 2011
    Co-Authors: Ricardo Barreto Portella, Luiza F. Andrade, Tomazo Garzia Neto, Nelson Coelho
    Abstract:

    Bulk Carriers have been developed since 1950 to carry large quantities of non-packed commodities such as grains, coal and iron Ore. Nowadays, there are some 5,000 bulk Carriers around the world and this number points to some concerns that affect owners of these types of ship and ports. One of these problems is the big waiting time at the ports that reaches 12% of the global fleet around the world at any given moment. At Brazilian iron Ore ports the time waiting average was of 6–8 days during 2006–2008. A concrete example is the VALE operation that responds from mineral resources exploration to mineral resources delivery, passing through mines, railroads, seaport terminals and shipping business, forming a logistic chain that can not be interrupted by the expected growth in trade and consequent port congestion. In view of this, PROJEMAR and VALE faced the challenge of designing Ore Carriers in such a way that it would not interfere with the logistics chain by delaying other ships at the loading or discharge terminal. As the cargo operation is taken as the initial point of the design conception, the expected final product is a ship able to safely take loading rates as high as 16,000 tons of Ore per hour, with each hold loaded in one pour and the ship fully loaded in one pass, resulting in fewer pours into the holds of the Ore carrier, faster loading operations and, consequently, a significant economy for the ship owner and for the port. The amount of extra steel needed over conventional designs: less than one percent. The fundamental idea of this new concept, which PROJEMAR calls “single-pour, single-pass” design, is a method of ballast control that is synchronized with the cargo loading, scientifically deballasting the ship during loading in a way that balances the forces induced by the incoming cargo. Potential hull loading stress problems can occur due to the manner in which Ore cargoes are loaded and due to the amount of cargo which is loaded in an individual hold. To avoid the creation of any unacceptable stresses in the ship’s structure, loading studies considering the planning of cargo loading and discharging operations, maximum allowable and minimum required mass of cargo for each hold and for adjacent holds as a function of the draught at mid-hold position in form of hold mass curves, calculations of still water shear forces and still water bending moments for each port loading condition and structural analysis are required to be developed on the early design stages. This ship loading concept is creating a new generation of Ore Carriers in such a way that the main class societies are nowadays developing new specific class notation dedicated to these ships. The purpose of this paper is to present the “single-pour, single pass” concept development and how it has been applied to the design of the new 400,000 DWT Ore Carriers that are being built for VALE in Chinese and KOrean shipyards, and to the 80,100 DWT Bauxite Carrier that are being built for LOG-IN in Brazil. The “single-pour, single pass” concept was also partially considered on the design of 12 VLCCs that are being converted to VLOCs for VALE in China with PROJEMAR’s design.Copyright © 2011 by ASME

  • single pour single pass loading an innovative concept for a new generation of Ore Carriers
    ASME 2011 30th International Conference on Ocean Offshore and Arctic Engineering, 2011
    Co-Authors: Ricardo Barreto Portella, Luiza F. Andrade, Tomazo Garzia Neto, Nelson Coelho
    Abstract:

    Bulk Carriers have been developed since 1950 to carry large quantities of non-packed commodities such as grains, coal and iron Ore. Nowadays, there are some 5,000 bulk Carriers around the world and this number points to some concerns that affect owners of these types of ship and ports. One of these problems is the big waiting time at the ports that reaches 12% of the global fleet around the world at any given moment. At Brazilian iron Ore ports the time waiting average was of 6–8 days during 2006–2008. A concrete example is the VALE operation that responds from mineral resources exploration to mineral resources delivery, passing through mines, railroads, seaport terminals and shipping business, forming a logistic chain that can not be interrupted by the expected growth in trade and consequent port congestion. In view of this, PROJEMAR and VALE faced the challenge of designing Ore Carriers in such a way that it would not interfere with the logistics chain by delaying other ships at the loading or discharge terminal. As the cargo operation is taken as the initial point of the design conception, the expected final product is a ship able to safely take loading rates as high as 16,000 tons of Ore per hour, with each hold loaded in one pour and the ship fully loaded in one pass, resulting in fewer pours into the holds of the Ore carrier, faster loading operations and, consequently, a significant economy for the ship owner and for the port. The amount of extra steel needed over conventional designs: less than one percent. The fundamental idea of this new concept, which PROJEMAR calls “single-pour, single-pass” design, is a method of ballast control that is synchronized with the cargo loading, scientifically deballasting the ship during loading in a way that balances the forces induced by the incoming cargo. Potential hull loading stress problems can occur due to the manner in which Ore cargoes are loaded and due to the amount of cargo which is loaded in an individual hold. To avoid the creation of any unacceptable stresses in the ship’s structure, loading studies considering the planning of cargo loading and discharging operations, maximum allowable and minimum required mass of cargo for each hold and for adjacent holds as a function of the draught at mid-hold position in form of hold mass curves, calculations of still water shear forces and still water bending moments for each port loading condition and structural analysis are required to be developed on the early design stages. This ship loading concept is creating a new generation of Ore Carriers in such a way that the main class societies are nowadays developing new specific class notation dedicated to these ships. The purpose of this paper is to present the “single-pour, single pass” concept development and how it has been applied to the design of the new 400,000 DWT Ore Carriers that are being built for VALE in Chinese and KOrean shipyards, and to the 80,100 DWT Bauxite Carrier that are being built for LOG-IN in Brazil. The “single-pour, single pass” concept was also partially considered on the design of 12 VLCCs that are being converted to VLOCs for VALE in China with PROJEMAR’s design.Copyright © 2011 by ASME

  • First Ocean Going Ships With Springing and Whipping Included in the Ship Design
    Volume 6: Ocean Engineering, 2011
    Co-Authors: Gaute Storhaug, Ricardo Barreto Portella, Tomazo Garzia Neto, Erlend Moe, Nelson Luiz Coelho Alves, Sun Gun Park, Dong-kwon Lee, Yooil Kim
    Abstract:

    It is well known that ships vibrate due to waves. The wave induced vibrations of the hull girder are referred to as springing (resonance) and whipping (transient vibration from impacts). These vibrations contribute to the fatigue damage of fatigue sensitive details. An Ore Carrier of 400 000 dwt is currently being built by DSME, and at time of delivery, it will be the world’s largest bulk (Ore) carrier. The scantlings of large ships must be carefully designed with respect to global loading, and when extending the design beyond experience, it is also wise to consider all aspects that may affect operation and the life time costs. The vessel will also enter a long term contract and is therefOre to be evaluated for 30 year Brazil-China operation. In order to minimize the risk of fatigue damage, the vessel is designed according to DNV’s class notation CSA-2 requiring direct calculations of the loading and strength. Further it has been requested to include the effect of springing and whipping in the design. Reliable numerical tools for assessing the additional fatigue effect of vibrations are non-existing. DNV has, however, developed an empirical guidance on how the additional effect may be taken into account based on previous development projects related to the effect of vibrations on large Ore Carriers Due to the size and route of operation of the new design, it has, however, been required by the owner to carry out model tests in both ballast and cargo condition in order to quantify the contribution from vibration. The results from this project have been used for verification and further calibration of DNV’s existing empirical guidance. A test program has been designed for the purpose of evaluating the consequence in head seas for the Brazil to China trade. Full scale measurements from previous development projects of Ore Carriers and model tests have been utilized to convert the current model tests results into estimated full scale results for the 400 000 dwt vessels. It is further important to carefully consider how the vibrations are to be included in the design verification, and to develop a procedure for taking into account the vibrations which results in reasonable scantlings based on in-service experience with similar designs and trades. This procedure has been developed, and a structural verification has been carried out for the design. The final outcome of the model test was in line with previous experience and in overall agreement with DNV’s empirical guidance, showing a significant contribution from vibrations to the fatigue damage. The springing/whipping vibrations mOre than doubled the fatigue damage compared to fatigue evaluation of the isolated wave induced loading. The cargo condition vibrated relatively mOre than experienced on smaller vessels. Various sources to establish the wave conditions for the Brazil to China Ore trade were used, and the different sources resulted in significant differences in the predicted fatigue life of the design.Copyright © 2011 by ASME

Tomazo Garzia Neto - One of the best experts on this subject based on the ideXlab platform.

  • Single-Pour/Single Pass Loading: An Innovative Concept for a New Generation of Ore Carriers
    Volume 6: Ocean Engineering, 2011
    Co-Authors: Ricardo Barreto Portella, Luiza F. Andrade, Tomazo Garzia Neto, Nelson Coelho
    Abstract:

    Bulk Carriers have been developed since 1950 to carry large quantities of non-packed commodities such as grains, coal and iron Ore. Nowadays, there are some 5,000 bulk Carriers around the world and this number points to some concerns that affect owners of these types of ship and ports. One of these problems is the big waiting time at the ports that reaches 12% of the global fleet around the world at any given moment. At Brazilian iron Ore ports the time waiting average was of 6–8 days during 2006–2008. A concrete example is the VALE operation that responds from mineral resources exploration to mineral resources delivery, passing through mines, railroads, seaport terminals and shipping business, forming a logistic chain that can not be interrupted by the expected growth in trade and consequent port congestion. In view of this, PROJEMAR and VALE faced the challenge of designing Ore Carriers in such a way that it would not interfere with the logistics chain by delaying other ships at the loading or discharge terminal. As the cargo operation is taken as the initial point of the design conception, the expected final product is a ship able to safely take loading rates as high as 16,000 tons of Ore per hour, with each hold loaded in one pour and the ship fully loaded in one pass, resulting in fewer pours into the holds of the Ore carrier, faster loading operations and, consequently, a significant economy for the ship owner and for the port. The amount of extra steel needed over conventional designs: less than one percent. The fundamental idea of this new concept, which PROJEMAR calls “single-pour, single-pass” design, is a method of ballast control that is synchronized with the cargo loading, scientifically deballasting the ship during loading in a way that balances the forces induced by the incoming cargo. Potential hull loading stress problems can occur due to the manner in which Ore cargoes are loaded and due to the amount of cargo which is loaded in an individual hold. To avoid the creation of any unacceptable stresses in the ship’s structure, loading studies considering the planning of cargo loading and discharging operations, maximum allowable and minimum required mass of cargo for each hold and for adjacent holds as a function of the draught at mid-hold position in form of hold mass curves, calculations of still water shear forces and still water bending moments for each port loading condition and structural analysis are required to be developed on the early design stages. This ship loading concept is creating a new generation of Ore Carriers in such a way that the main class societies are nowadays developing new specific class notation dedicated to these ships. The purpose of this paper is to present the “single-pour, single pass” concept development and how it has been applied to the design of the new 400,000 DWT Ore Carriers that are being built for VALE in Chinese and KOrean shipyards, and to the 80,100 DWT Bauxite Carrier that are being built for LOG-IN in Brazil. The “single-pour, single pass” concept was also partially considered on the design of 12 VLCCs that are being converted to VLOCs for VALE in China with PROJEMAR’s design.Copyright © 2011 by ASME

  • single pour single pass loading an innovative concept for a new generation of Ore Carriers
    ASME 2011 30th International Conference on Ocean Offshore and Arctic Engineering, 2011
    Co-Authors: Ricardo Barreto Portella, Luiza F. Andrade, Tomazo Garzia Neto, Nelson Coelho
    Abstract:

    Bulk Carriers have been developed since 1950 to carry large quantities of non-packed commodities such as grains, coal and iron Ore. Nowadays, there are some 5,000 bulk Carriers around the world and this number points to some concerns that affect owners of these types of ship and ports. One of these problems is the big waiting time at the ports that reaches 12% of the global fleet around the world at any given moment. At Brazilian iron Ore ports the time waiting average was of 6–8 days during 2006–2008. A concrete example is the VALE operation that responds from mineral resources exploration to mineral resources delivery, passing through mines, railroads, seaport terminals and shipping business, forming a logistic chain that can not be interrupted by the expected growth in trade and consequent port congestion. In view of this, PROJEMAR and VALE faced the challenge of designing Ore Carriers in such a way that it would not interfere with the logistics chain by delaying other ships at the loading or discharge terminal. As the cargo operation is taken as the initial point of the design conception, the expected final product is a ship able to safely take loading rates as high as 16,000 tons of Ore per hour, with each hold loaded in one pour and the ship fully loaded in one pass, resulting in fewer pours into the holds of the Ore carrier, faster loading operations and, consequently, a significant economy for the ship owner and for the port. The amount of extra steel needed over conventional designs: less than one percent. The fundamental idea of this new concept, which PROJEMAR calls “single-pour, single-pass” design, is a method of ballast control that is synchronized with the cargo loading, scientifically deballasting the ship during loading in a way that balances the forces induced by the incoming cargo. Potential hull loading stress problems can occur due to the manner in which Ore cargoes are loaded and due to the amount of cargo which is loaded in an individual hold. To avoid the creation of any unacceptable stresses in the ship’s structure, loading studies considering the planning of cargo loading and discharging operations, maximum allowable and minimum required mass of cargo for each hold and for adjacent holds as a function of the draught at mid-hold position in form of hold mass curves, calculations of still water shear forces and still water bending moments for each port loading condition and structural analysis are required to be developed on the early design stages. This ship loading concept is creating a new generation of Ore Carriers in such a way that the main class societies are nowadays developing new specific class notation dedicated to these ships. The purpose of this paper is to present the “single-pour, single pass” concept development and how it has been applied to the design of the new 400,000 DWT Ore Carriers that are being built for VALE in Chinese and KOrean shipyards, and to the 80,100 DWT Bauxite Carrier that are being built for LOG-IN in Brazil. The “single-pour, single pass” concept was also partially considered on the design of 12 VLCCs that are being converted to VLOCs for VALE in China with PROJEMAR’s design.Copyright © 2011 by ASME

  • First Ocean Going Ships With Springing and Whipping Included in the Ship Design
    Volume 6: Ocean Engineering, 2011
    Co-Authors: Gaute Storhaug, Ricardo Barreto Portella, Tomazo Garzia Neto, Erlend Moe, Nelson Luiz Coelho Alves, Sun Gun Park, Dong-kwon Lee, Yooil Kim
    Abstract:

    It is well known that ships vibrate due to waves. The wave induced vibrations of the hull girder are referred to as springing (resonance) and whipping (transient vibration from impacts). These vibrations contribute to the fatigue damage of fatigue sensitive details. An Ore Carrier of 400 000 dwt is currently being built by DSME, and at time of delivery, it will be the world’s largest bulk (Ore) carrier. The scantlings of large ships must be carefully designed with respect to global loading, and when extending the design beyond experience, it is also wise to consider all aspects that may affect operation and the life time costs. The vessel will also enter a long term contract and is therefOre to be evaluated for 30 year Brazil-China operation. In order to minimize the risk of fatigue damage, the vessel is designed according to DNV’s class notation CSA-2 requiring direct calculations of the loading and strength. Further it has been requested to include the effect of springing and whipping in the design. Reliable numerical tools for assessing the additional fatigue effect of vibrations are non-existing. DNV has, however, developed an empirical guidance on how the additional effect may be taken into account based on previous development projects related to the effect of vibrations on large Ore Carriers Due to the size and route of operation of the new design, it has, however, been required by the owner to carry out model tests in both ballast and cargo condition in order to quantify the contribution from vibration. The results from this project have been used for verification and further calibration of DNV’s existing empirical guidance. A test program has been designed for the purpose of evaluating the consequence in head seas for the Brazil to China trade. Full scale measurements from previous development projects of Ore Carriers and model tests have been utilized to convert the current model tests results into estimated full scale results for the 400 000 dwt vessels. It is further important to carefully consider how the vibrations are to be included in the design verification, and to develop a procedure for taking into account the vibrations which results in reasonable scantlings based on in-service experience with similar designs and trades. This procedure has been developed, and a structural verification has been carried out for the design. The final outcome of the model test was in line with previous experience and in overall agreement with DNV’s empirical guidance, showing a significant contribution from vibrations to the fatigue damage. The springing/whipping vibrations mOre than doubled the fatigue damage compared to fatigue evaluation of the isolated wave induced loading. The cargo condition vibrated relatively mOre than experienced on smaller vessels. Various sources to establish the wave conditions for the Brazil to China Ore trade were used, and the different sources resulted in significant differences in the predicted fatigue life of the design.Copyright © 2011 by ASME

Luiza F. Andrade - One of the best experts on this subject based on the ideXlab platform.

  • Single-Pour/Single Pass Loading: An Innovative Concept for a New Generation of Ore Carriers
    Volume 6: Ocean Engineering, 2011
    Co-Authors: Ricardo Barreto Portella, Luiza F. Andrade, Tomazo Garzia Neto, Nelson Coelho
    Abstract:

    Bulk Carriers have been developed since 1950 to carry large quantities of non-packed commodities such as grains, coal and iron Ore. Nowadays, there are some 5,000 bulk Carriers around the world and this number points to some concerns that affect owners of these types of ship and ports. One of these problems is the big waiting time at the ports that reaches 12% of the global fleet around the world at any given moment. At Brazilian iron Ore ports the time waiting average was of 6–8 days during 2006–2008. A concrete example is the VALE operation that responds from mineral resources exploration to mineral resources delivery, passing through mines, railroads, seaport terminals and shipping business, forming a logistic chain that can not be interrupted by the expected growth in trade and consequent port congestion. In view of this, PROJEMAR and VALE faced the challenge of designing Ore Carriers in such a way that it would not interfere with the logistics chain by delaying other ships at the loading or discharge terminal. As the cargo operation is taken as the initial point of the design conception, the expected final product is a ship able to safely take loading rates as high as 16,000 tons of Ore per hour, with each hold loaded in one pour and the ship fully loaded in one pass, resulting in fewer pours into the holds of the Ore carrier, faster loading operations and, consequently, a significant economy for the ship owner and for the port. The amount of extra steel needed over conventional designs: less than one percent. The fundamental idea of this new concept, which PROJEMAR calls “single-pour, single-pass” design, is a method of ballast control that is synchronized with the cargo loading, scientifically deballasting the ship during loading in a way that balances the forces induced by the incoming cargo. Potential hull loading stress problems can occur due to the manner in which Ore cargoes are loaded and due to the amount of cargo which is loaded in an individual hold. To avoid the creation of any unacceptable stresses in the ship’s structure, loading studies considering the planning of cargo loading and discharging operations, maximum allowable and minimum required mass of cargo for each hold and for adjacent holds as a function of the draught at mid-hold position in form of hold mass curves, calculations of still water shear forces and still water bending moments for each port loading condition and structural analysis are required to be developed on the early design stages. This ship loading concept is creating a new generation of Ore Carriers in such a way that the main class societies are nowadays developing new specific class notation dedicated to these ships. The purpose of this paper is to present the “single-pour, single pass” concept development and how it has been applied to the design of the new 400,000 DWT Ore Carriers that are being built for VALE in Chinese and KOrean shipyards, and to the 80,100 DWT Bauxite Carrier that are being built for LOG-IN in Brazil. The “single-pour, single pass” concept was also partially considered on the design of 12 VLCCs that are being converted to VLOCs for VALE in China with PROJEMAR’s design.Copyright © 2011 by ASME

  • single pour single pass loading an innovative concept for a new generation of Ore Carriers
    ASME 2011 30th International Conference on Ocean Offshore and Arctic Engineering, 2011
    Co-Authors: Ricardo Barreto Portella, Luiza F. Andrade, Tomazo Garzia Neto, Nelson Coelho
    Abstract:

    Bulk Carriers have been developed since 1950 to carry large quantities of non-packed commodities such as grains, coal and iron Ore. Nowadays, there are some 5,000 bulk Carriers around the world and this number points to some concerns that affect owners of these types of ship and ports. One of these problems is the big waiting time at the ports that reaches 12% of the global fleet around the world at any given moment. At Brazilian iron Ore ports the time waiting average was of 6–8 days during 2006–2008. A concrete example is the VALE operation that responds from mineral resources exploration to mineral resources delivery, passing through mines, railroads, seaport terminals and shipping business, forming a logistic chain that can not be interrupted by the expected growth in trade and consequent port congestion. In view of this, PROJEMAR and VALE faced the challenge of designing Ore Carriers in such a way that it would not interfere with the logistics chain by delaying other ships at the loading or discharge terminal. As the cargo operation is taken as the initial point of the design conception, the expected final product is a ship able to safely take loading rates as high as 16,000 tons of Ore per hour, with each hold loaded in one pour and the ship fully loaded in one pass, resulting in fewer pours into the holds of the Ore carrier, faster loading operations and, consequently, a significant economy for the ship owner and for the port. The amount of extra steel needed over conventional designs: less than one percent. The fundamental idea of this new concept, which PROJEMAR calls “single-pour, single-pass” design, is a method of ballast control that is synchronized with the cargo loading, scientifically deballasting the ship during loading in a way that balances the forces induced by the incoming cargo. Potential hull loading stress problems can occur due to the manner in which Ore cargoes are loaded and due to the amount of cargo which is loaded in an individual hold. To avoid the creation of any unacceptable stresses in the ship’s structure, loading studies considering the planning of cargo loading and discharging operations, maximum allowable and minimum required mass of cargo for each hold and for adjacent holds as a function of the draught at mid-hold position in form of hold mass curves, calculations of still water shear forces and still water bending moments for each port loading condition and structural analysis are required to be developed on the early design stages. This ship loading concept is creating a new generation of Ore Carriers in such a way that the main class societies are nowadays developing new specific class notation dedicated to these ships. The purpose of this paper is to present the “single-pour, single pass” concept development and how it has been applied to the design of the new 400,000 DWT Ore Carriers that are being built for VALE in Chinese and KOrean shipyards, and to the 80,100 DWT Bauxite Carrier that are being built for LOG-IN in Brazil. The “single-pour, single pass” concept was also partially considered on the design of 12 VLCCs that are being converted to VLOCs for VALE in China with PROJEMAR’s design.Copyright © 2011 by ASME

Ong, Muk Chen - One of the best experts on this subject based on the ideXlab platform.

  • Influence of linear springing on the fatigue damage of ultra large Ore Carriers
    MDPI, 2018
    Co-Authors: Li Hui, Di Wang, Liu Ning, Zhou Xueqian, Ong, Muk Chen
    Abstract:

    Springing occurs mOre frequently to ultra large ships, as their natural frequencies are relatively low and approaches the spectral peak of the wave energy spectrum in certain sea states. Springing is a resonance phenomenon between the waves and the ship hull, and this high frequency vibration has a significant influence on the fatigue damage of hull structures. This paper deals with the influence of springing on the fatigue damage of ultra large Ore Carriers. The springing responses of ultra large Ore Carriers are calculated by a three-dimensional linear hydroelasticity method in the frequency domain. A fatigue damage calculation method accounting for the springing effect is applied that is based on the fatigue spectrum analysis method and the approximation method of joint narrowband. The fatigue damage of the deck and bottom longitudinals in the deck and bottom of ultra large Ore Carriers of various sizes has been calculated by this method. The influences of ship size, structural damping, sea state, wave heading, navigational speed, and loading condition on the structure fatigue damage ratio of ultra large Ore carrier are analyzed.publishedVersio

  • Influence of linear springing on the fatigue damage of ultra large Ore Carriers
    'MDPI AG', 2018
    Co-Authors: Li Hui, Di Wang, Liu Ning, Zhou Xueqian, Ong, Muk Chen
    Abstract:

    Springing occurs mOre frequently to ultra large ships, as their natural frequencies are relatively low and approaches the spectral peak of the wave energy spectrum in certain sea states. Springing is a resonance phenomenon between the waves and the ship hull, and this high frequency vibration has a significant influence on the fatigue damage of hull structures. This paper deals with the influence of springing on the fatigue damage of ultra large Ore Carriers. The springing responses of ultra large Ore Carriers are calculated by a three-dimensional linear hydroelasticity method in the frequency domain. A fatigue damage calculation method accounting for the springing effect is applied that is based on the fatigue spectrum analysis method and the approximation method of joint narrowband. The fatigue damage of the deck and bottom longitudinals in the deck and bottom of ultra large Ore Carriers of various sizes has been calculated by this method. The influences of ship size, structural damping, sea state, wave heading, navigational speed, and loading condition on the structure fatigue damage ratio of ultra large Ore carrier are analyzed