The Optimisiation of the Floating Ball Valve Seat Component Design Methodology

The objective of this thesis is to optimise the design methodology through which the design of floating ball valves seats are designed. The lack of an established and accepted design methodology has led to numerous part-solutions being applied to the design process. The variations in design methodology lead to significant variations in designs produced and significant variations in the performance of these designs. In establishing an optimised design methodology this thesis takes the fundamental functions of a floating ball valve and develops a design methodology which when applied achieves a consistent and robust seat design for floating ball valves.

To develop the optimised floating ball valve seat design method this thesis first develops an understanding of the mechanics governing the fundamental features of the seat and its interaction with the ball component. The development of the understanding is started through the establishment of theoretical models describing the mechanics of the seat component based on established works. To further ensure the understanding of the seat component is correct a realistic computational model is developed. Through the evaluation of the data from the computational model the theoretical models can be compared to the realistic function of the seat component. Where there are differences between the results from the theoretical and computational models, the theoretical models are improved to be able to be applied to the computational model and generate representative results. Following on from the validation of the theoretical models, the theoretical models are re-arranged and combined in such a way that the models used to describe the mechanics can be used to determine design parameters. The design equations developed are combined into a complete design methodology through which a floating ball valve seat can be designed. Following the establishment of the floating ball valve seat design methodology, the methodology is applied to a case study to demonstrate the robustness and appropriateness of the methodology to designing floating ball valve seats.