【作者】 郝海滨；

【导师】 赵长财；

【作者基本信息】 燕山大学 ， 材料加工工程， 2014， 博士

【摘要】 高压气瓶是高压气体的主要盛装容器，广泛应用于电力、石油化工、轻工、纺织、冶金、机械、交通、采矿、医药等行业部门及日常生活中。由于高压气瓶工作时承受较高的压力载荷、接触腐蚀性介质，并且常应用于高温或深冷等极端工作条件下，因此是一种比较容易发生事故的特种设备。随着我国汽车保有量的不断增加，天然气汽车的推广不仅符合我国的经济发展战略，还可有效缓解能源短缺和大气污染。车载压缩天然气气瓶(Compressed Natural Gas，简称CNG气瓶）是CNG汽车的关键零部件之一，其安全性能一直受到国家和市场的重视。高压气瓶按制造工艺可分为两类：拉拔瓶和管制瓶。由于管制瓶瓶底的收底质量问题使其推广和应用受到了限制。而以钢坯为原材料的拉拔瓶，由于产品安全性能高、密封性能好、容重比高等优点越来越受到市场欢迎。目前，在欧美等先进国家拉拔瓶的使用越来越广泛。本文以圈模、辊模拉拔为基本研究对象，将圈模和辊模拉拔技术同时应用于CNG气瓶拉拔成形领域，用于解决CNG气瓶拉拔生产过程中的实际问题。论文以气瓶用34CrMo4合金钢为研究对象，通过材料拉伸实验、压缩实验得到了34CrMo4合金钢的动态回复型本构关系方程。针对CNG气瓶圈模、辊轮模拉拔进行了系统的理论分析，给出了圈模、辊轮模拉拔力理论计算公式。通过对圈模拉拔力分析，给出了拉拔力最小的最佳入模角取值范围，并通过有限元数值模拟验证了这一结论。利用有限元软件，对圈模拉拔和辊模拉拔进行数值模拟分析，得到了圈模拉拔力和辊模拉拔力随拉拔比、入模角、圆角半径、摩擦系数等工艺参数的变化规律。通过有限元模拟，研究了摩擦系数对辊轮模拉拔力的影响，发现轴承摩擦系数对轴向拉拔力和径向压制力影响较大，轴向拉拔力随摩擦系数的增大而增大，而辊轮径向压制力随摩擦系数的增大而减小。论文针对辊模拉拔进行了力学理论研究，得到了拉拔等速点公式和拉拔力的理论关系式。通过有限元数值模拟得到了拉拔力随拉拔比、瓶坯厚径比、摩擦系数等参数的变化规律。在相同拉拔比下，两道拉拔辊同时通过瓶坯时的拉拔力大于单道拉拔辊的拉拔力。对圈模拉拔和辊模拉拔的各工艺参数进行比较，得到在相同拉拔比条件下，辊模拉拔力低于圈模拉拔力，单道拉拔圈拉拔力小于两道拉拔圈的拉拔力，单道拉拔辊拉拔力小于两道拉拔辊的拉拔力。将辊模拉拔技术引入CNG气瓶制造技术，进行合理配模，设计了气瓶拉拔模具，并设计了专用拉拔设备及其生产线。本文研究结果为CNG气瓶的拉拔工艺配模设计和拉拔模具的设计提供了理论依据，对CNG气瓶拉拔生产具有重要理论意义和应用推广价值。更多还原

【Abstract】 High pressure gas cylinder is the main holding container of the high pressure, widelyused in electric power, petroleum chemical industry, light industry, textile, metallurgy,machinery, transportation, mining, pharmaceutical industries and daily life. Due to thehigh pressure and contact corrosive medium it endures during the work, and extremeoperating conditions such as high and low temperature, it is a relatively special equipmenteasy to have an accident. With the increase of car ownership, the promotion of natural gasvehicle not only conforms to our country’s economic development strategy, but also caneffectively relieve the energy shortage and air pollution. On-board compressed natural gascylinder (CNG gas cylinder) is one of the key components of CNG vehicle, its securityhas received great attention from the state and market.High pressure gas cylinder according to the manufacturing process can be dividedinto two categories: drawing bottle and tube-type bottle. Due to quality problem of thebottom of tube-type bottle, the development of the tube-type bottle is limited. But thedrawing bottle, using billet as its raw materials, due to the high product safetyperformance, good sealed performance, high bulk density, is more and more welcomed bythe market. At present, drawing bottle is widely used in Europe and the United States andother advanced countries.Based on the ring dies and roller dies drawing as the basic research object, the ringdies and roller dies drawing technology are both used in CNG gas cylinder drawingforming field, aim at solving the practical problems of CNG gas cylinder drawing in theprocess of production. In this paper, with gas cylinder steel34CrMo4as research object,through the material tensile test, compression test, the dynamic recovery constitutive lawsequations of34CrMo4alloy steel is obtained. Detailed theoretical analysis for CNG gascylinder ring dies and roller dies drawing were applied, which gives the ring dies androller dies drawing force theoretical calculation formulas. Through the analysis for thering dies drawing force, the value range of minimum best blank entry angles to mold aregiven, and this conclusion is verified by finite element numerical simulation. Using finite element software, the ring dies and roller dies drawing numerical simulation analysis isprocessed, the rule of variation of process parameters such as drawing ratio, die-entranceangle, the radius and friction coefficient with the ring dies and the roller dies drawingforce is obtained. the influence of the friction coefficient to the roller die drawing force isstudied, finding that bearing friction coefficient makes a great influence on the axialdrawing force and radial pressing force, the axial drawing force increases with theincreasing of the friction coefficient, the roller radial pressing force decreases with theincreasing of friction coefficient.The mechanics theory of roller dies drawing is studied, the theoretical relationformula between drawing speed point and drawing force is built. By finite elementnumerical simulation, the rule of variation of parameters, such as coefficient of friction,the bottle drawing ratio, slab thickness to diameter ratio changed with the drawing force isobtained. Under the same drawing ratio, drawing force of two passes rolling process islarger than single pass rolling process.Compared various process parameters of the ring dies and roller dies drawing underthe same drawing ratio condition, find that the roller dies drawing force is lower than ringdies drawing force, force of single pass ring drawing process is smaller than two passesring drawing process, and the one of single pass roller drawing process is smaller than twopasses roller drawing process. Through introducing the roller dies drawing technology toCNG gas cylinder manufacturing, carring on the reasonable die arrangement, the bottledrawing die was designed, same with the special drawing equipment and production line.In this paper, the results of the study provides a theoretical basis for CNG gascylinder die arrangement of drawing process and the die design, which has importanttheory meaning and application promotion value to the CNG gas cylinder drawingproduction.更多还原