Strength Analysis And Optimization Design Of Structure For WF2000Drilling Pump

Exploration and development of offshore oil resources will be more important in thefuture because the oil and gas resource onshore will be exhausted. The higher requirementsfor drilling equipment have been put forward in order to meet the deep water drillingoperation. As the key equipment of drilling fluid circulation system, mud pump is moving inthe direction of high horsepower, large displacement, high pump pressure and light weight.With the improvement of pumping pressure and horsepower, it is also significantly increasedthe strength and rigidity requirements for the parts of the mud pump itself. Due to variableload and space constraints of offshore drilling platform, it is required that the weight is lighterand the size is smaller as far as possible for mud pump. For the purpose, TSC Group proposeto design and develop WF2000triplex drilling pump with high power, high pressure, lightweight, and high reliability to meet offshore drilling platform’s requirements.First, we did a general plan of decision design for the new mud pump in accordance withthe functional requirement to optimize the overall design for structure of main components.On this basis, we adopted FEA to calculate the strength and rigidity of the pump. The resultilluminates that overall performance of this pump meets design requirement. Since the rigiditybalance is not ideal, it is possible to optimize some important parts. In order to shorten thecalculation cycle of the same type of mud pump, it is necessary to consider the transferring offinite element model for the same parts. The author uses substructure technique analysis tocalculate the strength and rigidity and optimize re-design for structure of key parts. With thesub-structure base, it will shorten calculation and design time for the similar follow-updrilling pumps, improve the reliability of analytical calculation and computational efficiency.The author makes dynamic analysis and design for the pump based on static structuraloptimum design, analyzes pump frame with a constraint mode, then obtain dynamiccharacteristic and make dynamic re-design by mode parameters to avoid oscillation modewhich is disadvantageous for the structure and to avoid resonance, thus provide a basis for theimprovement of pump frame overall optimization and design of drilling pump workingfrequency to greatly upgrade the performance of the pump. Finally, we manufactured a model pump and took static and dynamic tests for prototypeafter optimization design which showed this pump’s overall performance meets designrequirement, the weight is greatly reduced, structure rigidity is more balanced. Now this typeof drilling pumps have been equipped on many self-elevating drilling platforms in bigquantity. This thesis makes a general analysis and summary of WF2000drilling pump throughfinite element calculation, substructure optimization re-design, pump frame mode analysis,ultimate stress test, etc., provides a new design and analysis method for the design of newtype drilling pump.The following four aspects are completed in this thesis:1. Based on the summary of the theory about the key parts calculation, according to theprinciple of functional analysis, we optimized the key parts structure; according to finiteelement analysis of WF2000drilling pump key parts’ strength and rigidity, we found theshortage of structural design and the research direction for structure re-design.2. On the basis of sub-structure technology to achieve the goal of stress analysis andlightening total weight, optimization re-design of crank and pump frame of WF2000drillingpump were carried out.3. Using Block Lanczos method to make modal analysis of pump frame, extractingstructural low order modal parameters, obtaining natural frequency and main vibration mode,we analyzed the reason for the mode result, got the solution to avoid resonance, thus provide adesign basis for optimization of pump frame structure and general pump working frequency.4. Took stress test and deformation test on WF2000drilling pump frame. Test resultsverify that re-designed structure is optimized. Structure re-design is the primary method forthe design of drilling pump.