Utjecaj nesavršenosti zavarenih spojeva na njihov zamorni vijek

undergraduate thesis

• Title (english): Weld imperfections and their effect on the resulting fatigue life
• Author: Marko Širac
• Mentor: Smiljko Rudan (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2022-03-04, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Shipbuilding

Abstract

Zbog sve veće konkurencije na tržištu brodskog prijevoza brodovlasnici od brodogradilišta zahtijevaju konstrukciju brodova sve veće nosivosti i manje mase kako bi se povećala ekonomska isplativost brodova. Kako bi se povećala nosivost koriste se čelici visoke čvrstoće uz postojeća znanja o zavarivanju. Nedovoljna je pozornost usmjerena na ponašanje zavara, pogotovo uz svakodnevne nesavršenosti poput netočnosti pri spajanju limova (nepodudaranja). Kako je brod na moru izložen stalnom udaranju valova i drugim cikličkim opterećenjima važno je proučiti kako se zavari ponašaju kod dugotrajnog opterećenja. Uz dostupnost modernih tehnologija poput FEM analize može se doći do zaključaka potrebnih za povećavanje sigurnosti brodova.
Cilj ovog rada je proučiti koncentracije naprezanja te vidjeti koliko je zamorni vijek zavara kod nepodudaranja dvije ploče uslijed nesavršenog zavarivanja.

Abstract (english)

Due to increasing competition in the shipping market, shipowners are demanding from shipyards the construction of ships with increased capacity and lower weight in order to increase the economic viability of ships. In order to increase the load-bearing capacity, high-strength steels are used with existing knowledge of welding. Insufficient attention is focused on weld behavior, especially with everyday imperfections such as inaccuracies in joining plates (misalignment). As a ship at sea is exposed to the constant impact of waves, it is important to study how welds behave under long-term loading. With the availability of modern technologies such as FEM analysis, it is possible to come to the conclusions needed to increase the safety of ships.
The aim of this paper is to study stress concentrations and see how long the fatigue life of welds is when two plates are misaligned due to imperfect welding.

• Keywords: Zamorno opterećenje; zamorni vijek; nepodudaranje
• Keywords (english): Fatigue stress; fatigue life; misalignment
• Language: croatian
• URN:NBN: urn:nbn:hr:235:511149
• Study programme: Title: Naval Architecture; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka brodogradnje (sveučilišni prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka brodogradnje)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2024-02-25
• Created on: 2022-02-28 21:40:53