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Study On Clean Water-based Quenching Medium For Textile Steel Ring Travelers

Posted on:2010-12-16Degree:MasterType:Thesis
Country:ChinaCandidate:L N YinFull Text:PDF
GTID:2121360278475342Subject:Mechanical design and theory
Abstract/Summary:PDF Full Text Request
Heat treatment is very important in metallurgy and mechanical industry and it is a main method to optimize characteristics of metals. However, heat treatment usually causes environment pollution, especially the quenching oil. Currently, quenching oil is mostly used in quenching process of steel ring travelers and the waste oil is difficult to dispose. Therefore, it makes severe pollution of environment. Therefore, it is urgent to look for a clean quenching medium to replace oil in steel ring travelers production. For this purpose a series of researches were made in the thesis.Firstly, the rust-resist solution was used in the quenching process and was compared with PAG and PVA quenching solution. Through orthogonal experiments it is found that rust-resist solution could be used for steel ring travelers. However, it'll cause more oxide scales. To solve this problem PAG, PVA and PEG were added in rust-resist solution respectively and a series of experiments were made.The results show that: (1) when the rust-resist quenching medium was used in the quenching process, the hardness of steel ring travelers is higher than normal. However, the hardness could be lowered in following tampering process by means of the new tampering equipment. Besides, the rust-resist solution is easy to make and has low cost, so it is feasibility to use it as quenching medium. (2) It is found that 3%~9% PAG solution is suitable for the quenching of steel ring travelers through experiments. The hardness decrease when the concentration increases. And it could get the best performance with the concentration of 8%. However, it is very expensive. (3) 0.3%~0.5% PVA also could be used and the performance is expecially good with the concentration of 0.35%. But it is difficult to measure its concentration and clear the PVA film which attached to steel ring travelers in practice. (4) Based on experiments it is found that there would be more oxide scales if replace quenching oil with water-based quenching liquid, especially the rust-resist solution. To solve this problem PVA, PEG and PAG were added into the rust-resist solution, these three substances could form a layer of protective film on the surface of steel ring travelers, and this film is helpful to decrease the oxide scales. After comparing characteristics of these three substances, PAG was chosed with concentration of 10%. In addition, the optimal heat treatment process is obtained by orthogonal experiments, the heating temperature is 840℃and the holding time is one minute.This thesis has innovation as follows: (1) the rust-resist solution was used in quenching process and it has good performance. Besides, the solution is non-toxicity and cheap. (2) the problem of oxide scales was solved, as a result of that, the rust-resist quenching medium is being used in the factory and could be widely used in the future.
Keywords/Search Tags:heat treatment, quenching medium, oxide scales, steel ring traveler
PDF Full Text Request
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