PSI - Issue 72

Available online at www.sciencedirect.com

ScienceDirect

Procedia Structural Integrity 72 (2025) 270–277

12th Annual Conference of Society for Structural Integrity and Life (DIVK12) Numerical analysis of the thick-walled pipe stone diverter fatigue strength Dražan Kozak a, * , Janko Morosavljević a , Ivan Morosavljević a , Nenad Gubeljak b a University of Slavonski Brod, Mechanical Engineering Faculty in Slavonski Brod, Trg Ivane Brlić Mažuranić 2, Slavonski Brod 3 5000, Croatia b University of Maribor, Faculty of Mechanical Engineering, Smetanova ul. 17, Maribor SI-2000, Slovenia Abstract In the quarry located in Drniš, 150 tons of limestone per hour are prepared and transported through a production line, mostly crushed, and separated into a different product. The thick-walled pipes are often used as the redirection diverter for the stones to the other branches of the production line and/or to regulate the limestone flow. Calculation in this manuscript aimed to check how many cycles the dimensioned pipe can withstand before rupturing, and if the crack occurs, how long will it grow until the crack is unstable, and whether the initial crack that forms is going to cause a failure. Fatigue strength analysis shows that the fracture will occur at the place where the stones hit after 35090 cycles, which means after 7 hours and 46 minutes. A numerical analysis of the propagation of a semi-elliptical crack was performed using Ansys Workbench software. A semi-elliptical crack with the dimensions of a major radius of 1 mm and a minor radius of 0.5 mm was initiated on the inner wall of the pipe at the place where most of the stone hit. The crack in the II. crack propagation phase can propagate by 50.938 mm from the initial size, after which there will be unstable crack growth and final failure of the structure. By evaluating the integrity of the structure using the SINTAP procedure; the FAD diagram, for the initial state of the semi-elliptical crack, it was determined that the structure is in a safe area. © 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Aleksandar Sedmak, Branislav Djordjevic, Simon Sedmak Dr. Simon Sedmak, ssedmak@mas.bg.ac.rs, Innovation Center of Faculty of Mechanical Engineering, Belgrade, Serbia

Keywords: Fatigue strength; Fatigue failure; The quarry; SINTAP procedure; FAD diagram

* Corresponding author. /. E-mail address: dkozak@unisb.hr

2452-3216 © 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Aleksandar Sedmak, Branislav Djordjevic, Simon Sedmak Dr. Simon Sedmak, ssedmak@mas.bg.ac.rs, Innovation Center of Faculty of Mechanical Engineering, Belgrade, Serbia 10.1016/j.prostr.2025.08.103