1) The document describes a structural assessment of a crane on a heavy lift ship, including load analysis, finite element modeling, and fatigue life calculation to determine the crane's lifetime.
2) Stress analysis of different load cases showed maximum stresses of 20KN/cm^2 on the boom and 13.3KN/cm^2 on the housing. Fatigue analysis identified the maximum damage would occur on the boom tip after 25 years.
3) The analysis followed classification society rules and guidelines, matched the finite element model to the actual crane properties, and identified welds as more prone to fatigue failure than plating.
Transient three dimensional cfd modelling of ceilng fanLahiru Dilshan
Ceiling fans are used to get thermal comfort, especially in tropical countries. With the increment of the usage of air conditioners, the emission of CO2 is increased. But ceiling fans are a limited solution, that saves much energy compared to air conditioners. Ceiling fans generate a non-uniform velocity profile, so that, there is a non-uniform thermal environment. That non-uniform environment does not imply lower thermal comfort, that will give enough thermal comfort with low energy cost by air velocity. Hence, there will be difficulties of analysing with simple modelling techniques in that environment. So, to predict the performance of the ceiling fan required more accurate models.
The accurate model of a ceiling fan will generate complex geometry that makes difficulties for the simulation process and requires higher computational power. Because of that, there are several methods used to predict the performance of the ceiling fan using mathematical techniques but that will give an estimated value of properties in the surrounding.
Transient three dimensional cfd modelling of ceilng fanLahiru Dilshan
Ceiling fans are used to get thermal comfort, especially in tropical countries. With the increment of the usage of air conditioners, the emission of CO2 is increased. But ceiling fans are a limited solution, that saves much energy compared to air conditioners. Ceiling fans generate a non-uniform velocity profile, so that, there is a non-uniform thermal environment. That non-uniform environment does not imply lower thermal comfort, that will give enough thermal comfort with low energy cost by air velocity. Hence, there will be difficulties of analysing with simple modelling techniques in that environment. So, to predict the performance of the ceiling fan required more accurate models.
The accurate model of a ceiling fan will generate complex geometry that makes difficulties for the simulation process and requires higher computational power. Because of that, there are several methods used to predict the performance of the ceiling fan using mathematical techniques but that will give an estimated value of properties in the surrounding.
Subsea Hyperbaric Welding for Pipeline RepairNeil Woodward
A diver-assisted TIG welding system has been successfully employed for pipeline repair and tie-in in the North Sea for the last 20 years. Known as the ‘Pipeline Repair System’, it is operated in water depths down to 180msw. For the last ten years, research and development has been performed in the laboratory, investigating and establishing the capability of the Gas Metal Arc hyperbaric welding process for operation beyond water depths of 180msw (the diver-assisted limit) and down to 2,500msw for remote welding pipeline repair and hot tapping applications. Hyperbaric weld procedures have been qualified down to 1,000msw.
After an extensive equipment design, development, build and test programme the Remote Welding System (RWS) has recently been tested offshore at 310 and 940msw. The Remote Welding System is based upon similar operating principles to the diver-assisted equipment spread: a Habitat, to be deployed around the pipe, to facilitate the creation of a suitably dry fully inert welding environment, and a recoverable Power and Control Module (known as the POCO) to dock onto the Habitat and deploy the remote welding equipment.
The offshore test included full operational sequences of the anticipated pipeline repair scenario: deploying the Remote Welding Habitat (RWH) around the pipe; creating a dry welding environment; deploying the Remote Welding POCO (RWP) and Remote Welding Tool (RWT); entering the Habitat; pre-heating the pipe; multi-pass hyperbaric positional GMA welding and post-weld review; post-weld heating; recovering the Remote Welding Tool and POCO and re-deploying when necessary during the operation; and finally recovering the Remote Welding Habitat after completion of the welding sequence.
In order to qualify the remote welding technology, with the approval of DNV GL, and demonstrate that the offshore equipment is fully capable of producing acceptable welds comparable with those qualified in the laboratory, the 310 and 940msw root and multi-pass welds were subject to Visual, NDT and basic mechanical property testing. The results represent the world’s first acceptable hyperbaric GMA offshore welding operation in the 1,000msw range facilitating the successful capability for pipeline repair applications beyond diver depths.
A novel approach for incorporation of capillary and gravity into streamline s...Shusei Tanaka
The effective use of streamline simulators for flow simulation of multi-million cell detailed 3D models relies on the ability to take large simulation time-steps with few pressure solutions. For processes that are convective, the streamline approach works quite well while for flow simulation with compressibility, strong capillarity or strong gravity terms, the maximum time step size may be substantially reduced, limiting the utility of streamline simulation. This is the case when applying the conventional streamline operator-splitting approach, where the nonlinear terms associated with capillarity and gravity limit the time step. Earlier studies have shown the importance of an anti-diffusive correction in which numerical dispersion from the convective solution must be removed before capillary pressure can be accurately modeled. Evaluation of the antidiffusive term involves the solution of a local Riemann problem which, unfortunately, is difficult to determine in full field multi-dimensional problems with heterogeneity, and spatially variable viscosity, fluid velocity, and saturations. The alternative approach is to perform the operating splitting calculation with very small time-steps to minimize the numerical dispersion, but this is not an effective simulation strategy.
Experimental and numerical stress analysis of a rectangular wing structureLahiru Dilshan
Structures of an aircraft can be categorised as primary structural components and secondary structure components. Primary structure components are the components which lead to failure of the aircraft if such component is failed during the flight cycle. Secondary components are load sharing components in an aircraft but will not pave the way to catastrophic failure.
Designing aircraft structures should follow several strategies to assure safety. For that, there are three main methods used in designing and maintenance procedures. First one is the safe flight, which an aircraft component has a lifetime. That component is not used beyond that limit and should replace though it is not failed. The fail-safe method is another one that redundant systems or components are there to ensure there is another way to carry the load or do necessary control. The final one is the damage tolerance which measures the current damages are within acceptable limit and carry out the main functions until the next main maintenance process.
To determine the safety of a structure component load distribution, stress and strain variation, deflection can be used as parameters to make sure that component can withstand maximum allowable load with safety factor. There are several techniques used to get accurate results as numerical methods, Finite Element Method (FEM) and experimental methods. In the design process, those three steps are followed in an orderly manner to ensure the safety of an aircraft.
Subsea Hyperbaric Welding for Pipeline RepairNeil Woodward
A diver-assisted TIG welding system has been successfully employed for pipeline repair and tie-in in the North Sea for the last 20 years. Known as the ‘Pipeline Repair System’, it is operated in water depths down to 180msw. For the last ten years, research and development has been performed in the laboratory, investigating and establishing the capability of the Gas Metal Arc hyperbaric welding process for operation beyond water depths of 180msw (the diver-assisted limit) and down to 2,500msw for remote welding pipeline repair and hot tapping applications. Hyperbaric weld procedures have been qualified down to 1,000msw.
After an extensive equipment design, development, build and test programme the Remote Welding System (RWS) has recently been tested offshore at 310 and 940msw. The Remote Welding System is based upon similar operating principles to the diver-assisted equipment spread: a Habitat, to be deployed around the pipe, to facilitate the creation of a suitably dry fully inert welding environment, and a recoverable Power and Control Module (known as the POCO) to dock onto the Habitat and deploy the remote welding equipment.
The offshore test included full operational sequences of the anticipated pipeline repair scenario: deploying the Remote Welding Habitat (RWH) around the pipe; creating a dry welding environment; deploying the Remote Welding POCO (RWP) and Remote Welding Tool (RWT); entering the Habitat; pre-heating the pipe; multi-pass hyperbaric positional GMA welding and post-weld review; post-weld heating; recovering the Remote Welding Tool and POCO and re-deploying when necessary during the operation; and finally recovering the Remote Welding Habitat after completion of the welding sequence.
In order to qualify the remote welding technology, with the approval of DNV GL, and demonstrate that the offshore equipment is fully capable of producing acceptable welds comparable with those qualified in the laboratory, the 310 and 940msw root and multi-pass welds were subject to Visual, NDT and basic mechanical property testing. The results represent the world’s first acceptable hyperbaric GMA offshore welding operation in the 1,000msw range facilitating the successful capability for pipeline repair applications beyond diver depths.
A novel approach for incorporation of capillary and gravity into streamline s...Shusei Tanaka
The effective use of streamline simulators for flow simulation of multi-million cell detailed 3D models relies on the ability to take large simulation time-steps with few pressure solutions. For processes that are convective, the streamline approach works quite well while for flow simulation with compressibility, strong capillarity or strong gravity terms, the maximum time step size may be substantially reduced, limiting the utility of streamline simulation. This is the case when applying the conventional streamline operator-splitting approach, where the nonlinear terms associated with capillarity and gravity limit the time step. Earlier studies have shown the importance of an anti-diffusive correction in which numerical dispersion from the convective solution must be removed before capillary pressure can be accurately modeled. Evaluation of the antidiffusive term involves the solution of a local Riemann problem which, unfortunately, is difficult to determine in full field multi-dimensional problems with heterogeneity, and spatially variable viscosity, fluid velocity, and saturations. The alternative approach is to perform the operating splitting calculation with very small time-steps to minimize the numerical dispersion, but this is not an effective simulation strategy.
Experimental and numerical stress analysis of a rectangular wing structureLahiru Dilshan
Structures of an aircraft can be categorised as primary structural components and secondary structure components. Primary structure components are the components which lead to failure of the aircraft if such component is failed during the flight cycle. Secondary components are load sharing components in an aircraft but will not pave the way to catastrophic failure.
Designing aircraft structures should follow several strategies to assure safety. For that, there are three main methods used in designing and maintenance procedures. First one is the safe flight, which an aircraft component has a lifetime. That component is not used beyond that limit and should replace though it is not failed. The fail-safe method is another one that redundant systems or components are there to ensure there is another way to carry the load or do necessary control. The final one is the damage tolerance which measures the current damages are within acceptable limit and carry out the main functions until the next main maintenance process.
To determine the safety of a structure component load distribution, stress and strain variation, deflection can be used as parameters to make sure that component can withstand maximum allowable load with safety factor. There are several techniques used to get accurate results as numerical methods, Finite Element Method (FEM) and experimental methods. In the design process, those three steps are followed in an orderly manner to ensure the safety of an aircraft.
An Offshore supply vessel is a multi-task vessel and has to be designed for many different purposes. This is contrary to most other ships used worldwide. In general, the geographical location where the offshore activity takes place is an important indicator of the choice of supply vessel.
Factors like weather conditions, the amount of equipment needed and the distance from the shore are important for what properties the vessel should have. The deep-water oilfield market is becoming more important as the conventional oilfield market in shallow water cannot meet the energy requirements from the consuming market. The Offshore Supply Vessels (hereafter it is called OSVs) market is becoming booming and the demand for OSVs has never reached the extent like today in previous periods.
In this project, an offshore supply vessel will be designed according to ABS Rules.
FINITE ELEMENT ANALYSIS OF CONNECTING ROD OF MG-ALLOY ijiert bestjournal
The automobile engine connecting rod is a high volume production,critical component. It co nnects reciprocating piston to rotating crankshaft,transmitting the thrust of the piston to the crankshaft. Every vehicle that uses an internal combustion engine requires at least one connecting rod depending upon the number of cylinders in the engine. As the purp ose of the connecting rod is to transfer the reciprocating motion of the piston into rotary motion of the crankshaft. Connecting ro ds for automotive applications are typically manufactured by forging from either w rought steel or powdered metal. the material used f or this process is Mg-Alloy and also finite element analysis of connecting rod
Contact Pressure Validation of Steam Turbine Casing for Static Loading ConditionIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
Stress Analysis of Automotive Chassis with Various ThicknessesIOSR Journals
Abstract : This paper presents, stress analysis of a ladder type low loader truck chassis structure consisting of
C-beams design for application of 7.5 tonne was performed by using FEM. The commercial finite element
package CATIA version 5 was used for the solution of the problem. To reduce the expenses of the chassis of the
trucks, the chassis structure design should be changed or the thickness should be decreased. Also determination
of the stresses of a truck chassis before manufacturing is important due to the design improvement. In order to
achieve a reduction in the magnitude of stress at critical point of the chassis frame, side member thickness,
cross member thickness and position of cross member from rear end were varied. Numerical results showed that
if the thickness change is not possible, changing the position of cross member may be a good alternative.
Computed results are then compared to analytical calculation, where it is found that the maximum deflection
agrees well with theoretical approximation but varies on the magnitude aspect.
Keywords - Stress analysis, fatigue life prediction and finite element method etc.
Design of the wing box structure for the given wing geometry, weights and load factors. Microsoft Excel was used for all the calculations needed for this design. The complete structure was drafted using Solidworks CAD software.
1. Structural Assessment of Crane on Heavy Lift Ship
with Load Check and Fatigue Life Calculation check
and fatigue life calculation
Rostock, Feburary 1/ 2017
Udit Sood
EMship cohort: September 2016 February 2017
Supervisors: Prof. Dr.Eng./Hiroshima Univ. Patrick Kaeding, University of Rostock
Dr.-Ing. Thomas Lindemann, University of Rostock
Internship Supervisor: Mr. Helge Rathje, SAL Heavy Lift GmbH, Hamburg, Germany
Reviewer: Prof. Maciej Taczala, University of Szczecin
4. 4
Cranes: 2 x 1,000 mtons SWL,
combinable up to 2,000
mtons.
Safe
Working
Load:
1,000 MT @ 16m outreach
800 MT @ 25m outreach
500 MT @ 38m outreach
Slewing: 360 degree with hydraulic
motor drive
Luffing : 18.17 degree to 84.35 degree
Hoisting: Maximum boom tip height of
37.3 meters
Operating:
Conditions
5.4 degree inclination
(5 degree Heel and 2 degree
trim.)
Wind Speed: 20m/sec
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
183 Ship Cranes
Structural Assesment of Crane
5. • Fd=Duty factor
• Lg=dead load
• Fh=Live load
• Ll=Hoisting factor
• Lh1=Horizontal component due to the heel.
• Lh2=The next most unfavourable horizontal load.
• Lh3= The horizontal component due to trim.
• Lw=The most unfavourable wind load
Load case Type 1
Load case Type 2
Load case Type 3
the crane is considered in the stowed position
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
Lloyds Register Rules and Guidelines
5Structural Assesment of Crane
6. Crane Loads
Special Loads
Dead Loads
Hoist Loads
Dynamic Forces of
cargo
Dynamic Forces of
ship
Diagonals Pull loads
due to cargo.
Partial Drop off forces
Irregular LoadsRegular Loads
Wind Loads
Snow and Ice
Temperature
Dynamic load
testing
Buffering Forces
Loads due to the
safety system.
Tear off of hoist
loads
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
DNV-GL rules and guidelines for lifting appliances
6Structural Assesment of Crane
7. Design FEM
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
Matching the model with the actual crane material
properties
7Structural Assesment of Crane
Manufacturer FEM
8. Study MFG FEM Design FEM
Deflection: 350.4mm 350.3mm
Model Wt: 152 tons 151.7 tons
Material 940KN/mm^2,
102KN/mm^2
940KN/mm2,
102KN/mm2
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
Validation of result with manufacturer Data
MFG FEM Design FEM
61.3mm 46.9mm
157 tons 156.7 tons
Steel S-355 Steel S-355
9. • Wind conditions at 20m/sec
• List of ship 2 degree
• Trim of ship 5 degree
• Ship speed zero during cargo operation
• Temperature less than 150 degree
• Material of structure steel S355
• Wire stiffness and material properties matched with real crane
• No influence of waves
9
Load Case
S.No.
Boom angle.
(degrees)
load
(tons)
Outreach
Weight of
Boom(t)
Total
Weight
Force P(KN)
1 69.74 1000 (SWL) 16 152 1152 11301.12
2 54.04 800 (SWL) 25 152 952 9339.12
3 18.17 500 (SWL) 38 152 652 6396.12
4 54.04 500 25 152 652 6396.12
5 69.74 500 16 152 652 6396.12
6 18.17 350 38 152 502 4924.62
7 54.04 350 25 152 502 4924.62
8 18.17 250 38 152 402 3943.62
Physical conditions considered:
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
Analysing the Load Cases
Structural Assesment of Crane
10. Study Load Case 1 Load Case 2 Load Case 3 Load Case 4
Max Stress 20KN/cm2 20KN/cm2 10KN/cm2 11KN/cm2
Load 1000 tons 800 tons 500 tons 500 tons
Boom Ang 69.74 degree 54.04 degree 18.17 degree 54.04 degree
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
Stress History of Boom with inclination 5.4 deg
11. Study Load Case 1 Load Case 2 Load Case 3 Load Case 4
Max Stress 13.30KN/cm2 12.2KN/cm2 21.0KN/cm2 11.7KN/cm2
Load 1000 tons 800 tons 500 tons 500 tons
Boom Ang 69.74 degree 54.04 degree 18.17 degree 54.04 degree
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
Stress History of Housing with Inclination 5.4 degree
13. Analyze Crane
Loads
Review cargo
conditions
Generate load
radius curve
Count cargo operations
for 1.8 years
Finite element modelling
of crane
Calculate stress tensors at
nodes for all load cases
Determine hot spots and
generate stress history
Calculate Fatigue using
stress data.
Sum up data and
calculate damage
Begin
Calculate fatigue life of
crane
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
13Structural Assesment of Crane
14. Plate Analysis Weld Analysis
• Carried out to check failure of
plate
• Notch case of 120 to 160 used
• Analysed by coarse grid stresses
• MATLAB program used for
analysis
• Carried out to check failure of
welds
• Notch case of 80 to 120 used
• Analysed by special fatigue finite
element module
• More elaborate approach used
for analysis
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
14Structural Assesment of Crane
15. Maximum damage given by manufacturer
Damage difference=0.71-0.663=0.047
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
Maximum damage calculated on welds :
=~ 0.71
1.00
Locating Maximum Fatigue Damage
15Structural Assesment of Crane
16. Plate fatigue determination
• Grid stresses obtained
• Plate joining located
• Notch case of 120 to 160
• Damage found at each grid point
• Cumulative damage found by summing
the results of 8 load cases
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
16Structural Assesment of Crane
17. Maximum boom outreach (38mts) is the limiting load case
• Housing deflections are maximum (46.9mm)
• Horizontal bearing forces are maximum
Maximum fatigue damage is found to occur on the boom tip after 25 years
of lifetime
Structure welds are more prone to fatigue failure compared to the plating
The housing bottom plating and the foundation shape is critical for
analysis and hot spot point of view
Windows on the housings need to be optimized with regard to minimum
area and clear visibility
Introduction Scope Comparison Analysis Simulation Fatigue Calc. Conclusion
Important Findings
17Structural Assesment of Crane
18. 18Structural Assesment of Crane
Structural Assessment and Fatigue Life Determination Tool in
Order to Simplify the Inspection Task Onboard