Development and design optimisation of digital intensity measurement system for shot peening

• Main Author: Tarani, Dinesh Kumar
• Other Authors: Yeo Swee Hock
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Engineering; Shot-peening; Intensity measurement
• Online Access: https://hdl.handle.net/10356/177236
• Institution: Nanyang Technological University

Shot peening, widely utilised across many different industries, is a cold working process employed to convert detrimental tensile stresses into beneficial compressive residual stresses, thereby enhancing the fatigue resistance of components. The current technique employed for determining shot peening intensities and validating process parameters in production relies on the utilization of Almen strips and saturation curves. Almen strips have been utilised in shot peening for several decades. The method was developed in the mid-20th century by John Almen and has since become a standard practice in the industry for measuring shot peening intensity and validating process parameters. Despite being a well-established process, it still exhibits certain drawbacks. For instance, measurements cannot be stored over a longer period of time due to material relaxation, online intensity verification is not viable and the process itself can be quite time consuming, depending on the complexity of the part to be peened. Additionally, Almen strips are designed for single use only, leading to significant wastage. As a result, the shot peening process has emerged as a common bottleneck in production due to long times associated with developing saturation curves using Almen strips. While Almen strips remain a widely used method for measuring shot peening intensity, there have been advancements and alternative methods developed over time. Unfortunately, these alternatives are extremely costly and impractical within a production setting. In alignment with the principles of Industry 4.0, the main objective is to transition from manual tasks to digitally optimised processes by integrating advanced technologies such as sensors and Internet of Things. In this study, the exploration of intensity verification using a force sensor aims to identify a process that is not only convenient but also affordable to acquire and applicable within a production line. The force sensor readings are recorded at different air pressures and mass flow rates, the two primary parameters that affect peening intensity. A restrictive plate is used to reduce the number of shots impacting the sensor. Three plates with different opening sizes are utilized, and the resulting outcomes are compared. Finally, the results underscore the potential of the force sensor. However, additional exploration is required to translate the findings of this study into a device suitable for integration into the production line as a substitute for or alternative to Almen strip measurement.