CP Check Valve Design

This report is to serve as a final design review and update to the project sponsors at Zurn Wilkins for the Check Valve Design Senior Project. The senior project team was tasked with improving upon the design of Zurn Wilkins’ backflow prevention assembly for small diameter pipes by reducing the pressure loss created by the check valves within the double check backflow assembly. The information contained in this report builds off the information contained in the Critical Design Report (CDR), as well as feedback and further investigation suggested during an Intermediary Design Review. Based on conclusions from the CDR, our team settled on developing one main design, referred to as the double-disk check valve. The goal of this design is to use the mechanical advantage of two actuating half-disk poppets connected to a central hinge to allow for greater cross-sectional flow area during open flow conditions, reducing pressure loss for each check valve.This report explains the decision behind the double-disk design and includes discussion on design alternatives that were considered. Our team provides analysis of data defending the final design direction, manufacturing plans, material selections, anticipated costs, and the results of iterative testing of various prototypes. Prior to March 18th, 2020, our team anticipated using the remaining months of the project to iterate upon the double-disk design through prototyping and testing at Zurn Wilkins’ wet lab facility. Due to the COVID-19 pandemic, the team has needed to modify the scope of the project. The double-disk design was instead finalized using analytical methods. However, due to health restrictions the team was not able to manufacture a model of this proposed design. We were able to work with our sponsor at Zurn to have one final prototype tested to help validate our models. The final design proposed by the team is a culmination of the testing, research, and analysis performed over the course of this project and is intended to serve as a stepping stone for future work in the reduction of pressure loss in the double check backflow assembly for ¼”- 2” diameter systems.