【Daily Question】July 14 – Turbine lifespan (80 points for participation + 2 points, plus 3–8 points for a correct answer)..
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This post was last edited by Cuicui Chang on 2015-7-17 at 15:36. The Machinery Section has introduced the \"Question of the Day\" feature, which aims to foster an active atmosphere for technical discussions and guide the direction of such exchanges. It also provides users with financial rewards, helping them experience various cool features. Q&A: 1. How is the lifespan of a turbine determined? Answer: The service life of a turbine refers to the total operating time from its initial commissioning until the first macroscopic crack appears in the rotor. There is no unified standard for the size of macroscopic cracks. It is generally believed that the length of macroscopic cracks is 0.2–0.5 MM. Requirements and hints for answering questions: Please reply with the answer you believe to be correct. If you provide a detailed explanation or analysis of the question or answer, an additional reward will be given. Extra rewards will be awarded if your answer is correct and your explanation is thorough and accurate. Feel free to answer the questions. Please note: We will close this thread after 24 hours, and at that time we will announce the best reply (the best assistance), as well as the answer and explanation. Please do not answer the question repeatedly. As a reward for your effort, if you post a topic in this section within two days that provides a detailed explanation of the knowledge points related to this question, please reply or leave a comment in this post to let us know; we will then ask a moderator to grant you + Charm. It is not allowed to simply copy and paste; original content is preferred, with at least some organization by the user along with personal insights. After registration, we will rank based on the content of the posts: the last-place contestant will receive +1 charm, the second-to-last +2 charm, and so on, with the highest score earning +5 charm. Call for weekly topics and daily questions (prizes for participation) [Mechanical Section] Collection of essential knowledge [Seeking manufacturer sponsorship] (long-term campaign) [Rewards for recommending valuable content] Summary of daily questions and answers related to mechanical equipment for 2015
The life loss of a turbine includes two components: low-cycle fatigue life loss and creep life loss. Fatigue is determined by the number of cycles, while creep is determined by the time spent operating under steady conditions.
The question is a bit too broad – rotor life? Or stator life? :dizzy:
How is the lifespan of a steam turbine determined? The lifespan of a turbine refers to the lifespan of its rotor, which is generally divided into crack-free lifespan and remaining lifespan. 1. Crack-free life refers to the operating time that the rotor experiences from its first commissioning until the first engineering crack appears. 2. Crack-free life is also known as fracture life. 3. According to fracture mechanics analysis, the appearance of the first crack does not mean the end of the rotor’s lifespan; there is still some remaining life, and this portion accounts for a significant proportion of the total lifespan. Crack instability and subsequent rotor failure occur only when the crack expands beyond the critical size. Therefore, remaining life refers to the safe operating time from the occurrence of the first engineering crack until the crack expands to a critical size. 2.5 The sum of the crack-free life and the remaining life is the total life of the rotor.
The lifespan of a turbine refers to the lifespan of its rotor, which is divided into crack-free lifespan and remaining lifespan. Crack-free life refers to the operating time that the rotor experiences from its first commissioning until the first engineering crack appears. Remaining life refers to the operating time from the appearance of the first crack until crack growth exceeds the critical size, resulting in rotor failure. Generally, the service life of domestic units is 20–25 years, with a maximum of no more than 30 years. The typical service life of foreign units is 30–40 years.
How is the lifespan of a steam turbine determined? Answer: (1) Based on the characteristics of wear and damage to the turbine’s lifespan caused by normal start-up and shutdown processes, variable loads, as well as other abnormal operating conditions, the turbine’s lifespan is planned and allocated in a rational manner to ensure that it reaches its intended service life. One should not simply “pursue” longevity. (2) In turbines operating at high temperatures, the material properties of their components change significantly, reducing their strength and leading to cracks. The service life of a turbine refers to the total operating time from its initial commissioning until the first macroscopic crack appears in the rotor. There is no unified standard for the size of macroscopic cracks. It is generally believed that the length of macroscopic cracks is 0.2–0.5 MM.
The life loss of a turbine includes two components: low-cycle fatigue life loss and creep life loss. Fatigue is determined by the number of cycles, while creep is determined by the time spent operating under steady conditions.
The life loss of a turbine includes two components: low-cycle fatigue life loss and creep life loss. Fatigue is determined by the number of cycles, while creep is determined by the time spent operating under steady conditions.
How is the lifespan of a steam turbine determined? (1) Based on the characteristics of wear and damage to the turbine’s lifespan caused by normal start-up and shutdown processes, variable loads, as well as other abnormal operating conditions, the turbine’s lifespan is planned and allocated in a rational manner to ensure that it achieves its intended service life. One should not simply “pursue” longevity. (2) In turbines operating at high temperatures, the material properties of their components change significantly, reducing their strength and leading to cracks. The service life of a turbine refers to the total operating time from its initial commissioning until the first macroscopic crack appears in the rotor. There is no unified standard for the size of macroscopic cracks. It is generally believed that the length of macroscopic cracks is 0.2–0.5 MM.
1. Based on the characteristics of wear and damage to the turbine’s lifespan caused by normal start-up and shutdown processes, variable loads, as well as other abnormal operating conditions, the turbine’s lifespan is planned and allocated in a rational manner to ensure that it achieves its intended service life. One should not simply “pursue” longevity. 2. In turbines operating at high temperatures, the material properties of their components change significantly, resulting in a decrease in their strength and ultimately the formation of cracks. The service life of a turbine refers to the total operating time from its initial commissioning until the first macroscopic crack appears in the rotor. There is no unified standard for the size of macroscopic cracks. It is generally believed that the length of macroscopic cracks is 0.2–0.5 mm.
The time elapsed from the start of operation of the new machine until the first crack of about 0.2–0.5 mm appeared on the shaft