[Q&A Question 198] 2017.07.17
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【Q&A Question 198】July 17, 2017: How does creep rupture of pressure vessels occur? The reference answers will be visible after responding; scoring is granted by identifying the key points. (Unless otherwise specified, all questions and answers are based on hydrogenation units.) ) Note: For questions of the type \"one question per day,\" if a person replies continuously for a month, that is, posts more than 30 times, their score will be assigned as 2 points, which is the lowest possible score. Click once to reply; if multiple replies are made, points will be awarded as appropriate, as deleting posts is also a waste of time. ①When metal materials are subjected to tensile stress at high temperatures over a long period of time, even if this tensile stress is lower than the material’s yield limit, the material will still undergo slow plastic deformation; this type of deformation is known as creep ； ②However, for creep to occur, three conditions must be present simultaneously: high temperature, prolonged time, and tensile stress ； ③The volume of the container that undergoes creep increases, while its wall thickness decreases significantly. This ultimately leads to the rupture of the container. Scoring criteria: 2 Wealth points for incorrect responses; *incomplete* answers earn 3–8 points. 10 Wealth points are given for correct answers accompanied by detailed explanations; responses that are correct but lack sufficient details earn 15–20 Wealth points. Please score according to these criteria. Note: If there are editing records after answering, only those who participated will be credited points. For continuous malicious spamming, 2 points will be deducted each time, with no upper limit. Pure numbers, pure emojis, or random letters that have nothing to do with the answer are all considered malicious spamming; points will start to be deducted after three warnings. 2017 Q&A Summary Thread (updates starting now) http://bbs.hcbbs.com/thread-1657793-1-1.html 2017 Daily Question Summary Thread (updates starting now) http://bbs.hcbbs.com/thread-1657794-1-1.html 2016 Q&A Summary Thread (updates completed) http://bbs.hcbbs.com/thread-1597792-1-1.html Petrochemical Sector – “Creative Ideas for Energy Savings” Campaign (Second phase is in full swing) http://bbs.hcbbs.com/thread-1666758-1-1.html 2017 Coal Chemicals – “My Technical Upgrades” http://bbs.hcbbs.com/thread-1786290-1-1.html
The base material of pressure vessels is subjected to tensile stress at high temperatures over a long period of time. Although this tensile stress is less than the material’s yield limit, the material still undergoes gradual plastic deformation, a phenomenon known as creep. The factor that causes creep is the container being exposed to high temperatures and tensile stresses over a prolonged period of time, which leads to creep. The volume of the container that undergoes creep increases, its walls thin out, and eventually this leads to the rupture of the container. The failure of a container caused by the creep of the material is known as creep rupture
When the operating temperature exceeds a certain limit, the material undergoes slow plastic deformation under stress; over time, this plastic deformation eventually leads to the rupture of the material, and such failure is known as creep fracture.
The container being exposed to high temperatures and tensile stresses for an extended period causes its walls to thin out, eventually leading to the container’s rupture
When metal materials are subjected to tensile stress at high temperatures over a long period of time, even if this tensile stress is lower than the material’s yield limit, the material will still undergo slow plastic deformation; this type of deformation is known as creep； However, for creep to occur, three conditions must be present simultaneously: high temperature, prolonged time, and tensile stress ； The volume of the container that undergoes creep increases, while its wall thickness decreases significantly. This ultimately leads to the rupture of the container.
This post was last edited by qybhdyb on 2017-7-17 09:17. ① When metal materials are subjected to tensile stress at high temperatures over a long period of time, even if this tensile stress is less than the material’s yield limit, the material will still undergo slow plastic deformation; this type of deformation is known as creep； ②However, for creep to occur, three conditions must be present simultaneously: high temperature, prolonged time, and tensile stress ； ③The volume of the container that undergoes creep increases, while its wall thickness decreases significantly. This ultimately leads to the rupture of the container.
①When metal materials are subjected to tensile stress at high temperatures over a long period of time, even if this tensile stress is lower than the material’s yield limit, the material will still undergo slow plastic deformation; this type of deformation is known as creep； ②However, for creep to occur, three conditions must be present simultaneously: high temperature, prolonged time, and tensile stress ； ③The volume of the container that undergoes creep increases, while its wall thickness decreases significantly. This ultimately leads to the rupture of the container.
①When metal materials are subjected to tensile stress at high temperatures over a long period of time, even if this tensile stress is lower than the material’s yield limit, the material will still undergo slow plastic deformation; this type of deformation is known as creep； ②However, for creep to occur, three conditions must be present simultaneously: high temperature, prolonged time, and tensile stress ； ③The volume of the container that undergoes creep increases, while its wall thickness decreases significantly. This ultimately leads to the rupture of the container.
①When metal materials are subjected to tensile stress at high temperatures over a long period of time, even if this tensile stress is lower than the material’s yield limit, the material will still undergo slow plastic deformation; this type of deformation is known as creep； ②However, for creep to occur, three conditions must be present simultaneously: high temperature, prolonged time, and tensile stress ； ③The volume of the container that undergoes creep increases, while its wall thickness decreases significantly. This ultimately leads to the rupture of the container.
①Creep failure of pressure vessels often occurs due to the vessel operating at a high temperature for an extended period of time; even if the stress is below the material’s yield limit, the material can still undergo slow plastic deformation； ②Pressure vessels suffer from creep failure due to improper material selection and unreasonable design ； ③The container experiences local overheating due to heat transfer impairment caused by scaling, carbonization, scarring, and other issues.