發(fā)布時(shí)間：2018-04-01 07:03

  本文選題：安全閥　切入點(diǎn)：研磨機(jī)構(gòu)　出處：《江南大學(xué)》2017年碩士論文

【摘要】：安全閥是安裝在承壓類設(shè)備上的一種超壓自動泄放裝置,其閥座和閥瓣是確保安全閥良好密封性能的關(guān)鍵零部件,通常采用金屬對金屬平面密封的結(jié)構(gòu)形式。在長期工作運(yùn)行中,安全閥關(guān)閉件由于受到腐蝕、裂紋、磨損等影響造成密封失效,從而嚴(yán)重導(dǎo)致安全閥泄漏量超標(biāo)。因此,安全閥的校驗(yàn)和維修工作就顯得尤為重要。針對安全閥關(guān)閉件的研磨修復(fù)問題,本文設(shè)計(jì)開發(fā)了新型的安全閥研磨設(shè)備,應(yīng)用Matlab仿真模擬閥瓣運(yùn)動軌跡來合理選定研磨機(jī)構(gòu)加工參數(shù);著重研究了表面粗糙度與密封性能的影響關(guān)系,為實(shí)驗(yàn)選用粗糙度評定表面質(zhì)量提供理論基礎(chǔ);以開發(fā)的新型研磨機(jī)構(gòu)為設(shè)備基礎(chǔ)進(jìn)行研磨實(shí)驗(yàn),制定了閥瓣研磨加工標(biāo)準(zhǔn)工藝路線,有效提高研磨效率和表面質(zhì)量。本文的主要研究內(nèi)容及成果如下:首先,采用Solidworks三維軟件,建立安全閥閥座研磨機(jī)構(gòu)和閥瓣研磨機(jī)構(gòu)的三維模型,對機(jī)構(gòu)的各關(guān)鍵部件包括支架、研磨頭、機(jī)械臂等進(jìn)行了結(jié)構(gòu)優(yōu)化,并對關(guān)鍵部件的運(yùn)動特征進(jìn)行了描述。其次,假設(shè)閥瓣全部分布在磨具的前提下,應(yīng)用力學(xué)與運(yùn)動學(xué)基本理論,對研磨過程閥瓣與磨具接觸區(qū)域的壓強(qiáng)分布及磨具受到的摩擦力矩進(jìn)行了研究,得出偏心距、磨具轉(zhuǎn)速是影響閥瓣轉(zhuǎn)速的主要工藝參數(shù)。通過推導(dǎo)的單顆磨粒研磨方程,應(yīng)用Matlab對閥瓣運(yùn)動軌跡進(jìn)行了仿真,發(fā)現(xiàn)轉(zhuǎn)速比、偏心距、磨具轉(zhuǎn)速、工件的初始位置是影響磨粒軌跡形態(tài)的主要因素。然后,對安全閥關(guān)閉件的磨削過程進(jìn)行了理論研究,應(yīng)用高斯分布函數(shù)建立了微觀表面粗糙度的數(shù)學(xué)模型,得出隨著表面粗糙度的增大,金屬表面起伏程度越來越顯著。研究了研磨介質(zhì)與關(guān)閉件之間的相對運(yùn)動特征對粗糙度的形成關(guān)系,并通過密封試驗(yàn)研究表面粗糙度、工作壓力對安全閥關(guān)閉件泄漏量的影響,這為后續(xù)實(shí)驗(yàn)對研磨介質(zhì)、研磨壓力的選擇以及用粗糙度評定表面質(zhì)量提供一定的理論基礎(chǔ)。最后,優(yōu)化閥瓣粗磨和精磨工藝參數(shù),制定研磨維修新工藝路線。以不同細(xì)度的砂紙作為研磨介質(zhì),采用SAS正交實(shí)驗(yàn)研究研磨壓力、研磨時(shí)間、研磨轉(zhuǎn)速在閥瓣粗磨和精磨工藝階段對材料去除率、表面粗糙度及表面微觀形貌的影響,并綜合優(yōu)化獲得高效率和優(yōu)質(zhì)量的工藝參數(shù)。結(jié)果表明:在粗磨過程中,研磨壓力為15 N,研磨轉(zhuǎn)速為30 rpm,研磨時(shí)間為10 min是最佳工藝參數(shù)組合,材料去除率MRR為27.5μm/min,表面粗糙度Ra為0.213μm。在精磨過程中,研磨壓力為15 N,研磨轉(zhuǎn)速為20 rpm,研磨時(shí)間為4 min是最佳工藝參數(shù)組合,可獲得材料去除率MRR為2.15μm/min,表面粗糙度Ra為0.102μm。本文關(guān)于安全閥閥座與閥瓣密封面維修設(shè)備的開發(fā)對實(shí)現(xiàn)連續(xù)自動化具有重要的工程應(yīng)用價(jià)值,研磨工藝的研究為提高工件表面質(zhì)量提供了堅(jiān)實(shí)的理論基礎(chǔ)。
[Abstract]:The safety valve is a kind of overpressure automatic relief device installed on the pressure equipment. Its seat and disc are the key parts to ensure the good sealing performance of the safety valve. The structure of metal to metal plane seal is usually adopted. In the long-term operation, the sealing failure of the safety valve closure is caused by corrosion, cracks, wear and so on, which seriously causes the leakage of the safety valve to exceed the standard. It is very important to check and maintain the safety valve. Aiming at the problem of grinding and repairing the safety valve closure, a new type of safety valve grinding equipment is designed and developed in this paper. The machining parameters of grinding mechanism are reasonably selected by using Matlab simulation to simulate disc motion trajectory, and the relationship between surface roughness and sealing performance is studied, which provides a theoretical basis for the experiment to select roughness to evaluate the surface quality. Based on the new lapping mechanism developed, the grinding experiment was carried out, and the standard technological route of disc grinding was worked out, which effectively improved the grinding efficiency and surface quality. The main contents and achievements of this paper are as follows: first of all, The 3D model of safety valve seat grinding mechanism and disc grinding mechanism is established by using Solidworks software. The key components of the mechanism, including the support, the grinding head, the mechanical arm and so on, are optimized. The motion characteristics of the key components are described. Secondly, assuming that the disc is all distributed in the grinding tool, the basic theory of mechanics and kinematics is applied. The pressure distribution in the contact area between disc and abrasive tool and the friction moment of grinding tool are studied. It is concluded that eccentricity and grinding tool speed are the main technological parameters affecting disc speed. The grinding equation of single abrasive particle is derived. The movement trajectory of disc is simulated by Matlab. It is found that rotational speed ratio, eccentricity, grinding tool speed and the initial position of workpiece are the main factors that affect the shape of abrasive particle trajectory. Then, the grinding process of safety valve closure is studied theoretically. The mathematical model of micro surface roughness is established by using Gao Si distribution function, and it is concluded that with the increase of surface roughness, The effect of surface roughness and working pressure on the leakage of safety valve closure is studied by sealing test. This provides a theoretical basis for further experiments on the selection of grinding medium, grinding pressure and surface quality evaluation with roughness. Finally, the process parameters of disc roughing and finishing grinding are optimized. The new grinding maintenance technology route was established. The grinding pressure, grinding time and grinding speed were studied by SAS orthogonal experiment with different fineness sandpaper as grinding medium. The material removal rate was studied in the stage of disc roughing and finishing grinding. The effects of surface roughness and surface micromorphology on the process parameters of high efficiency and high quality were comprehensively optimized. The results showed that: in the process of rough grinding, The optimum process parameters are lapping pressure of 15 N, grinding speed of 30 rpm and grinding time of 10 min. The material removal rate (MRR) is 27.5 渭 m / min, and the surface roughness Ra is 0.213 渭 m. The optimum process parameters are 15 N grinding pressure, 20 rpm grinding speed and 4 min grinding time. The available material removal rate (MRR) is 2.15 渭 m / min and the surface roughness (Ra) is 0.102 渭 m. In this paper, the development of maintenance equipment for relief valve seat and disc sealing surface has important engineering application value for realizing continuous automation. The study of grinding technology provides a solid theoretical basis for improving the surface quality of workpiece.
【學(xué)位授予單位】：江南大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TH134

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 譚悅;陳燕;曾加恒;許召寬;;電解 磁力復(fù)合研磨對TA18管內(nèi)表面光整加工[J];電鍍與涂飾;2017年05期

2 楊波;王曉;李茂東;;磁流體研磨技術(shù)在安全閥研磨修復(fù)中的應(yīng)用研究[J];現(xiàn)代化工;2016年12期

3 韓冰;云昊;陳燕;廖明;;振動輔助磁力研磨超硬精密Al_2O_3陶瓷管內(nèi)表面試驗(yàn)研究[J];摩擦學(xué)學(xué)報(bào);2016年02期

4 呂祥奎;楊文健;許國良;黃曉明;;密封結(jié)構(gòu)中粗糙表面特征對其氣密性的影響[J];機(jī)械工程學(xué)報(bào);2015年23期

5 李軍;王慧敏;王文澤;黃建東;朱永偉;左敦穩(wěn);;固結(jié)磨料研磨K9玻璃表面粗糙度模型[J];機(jī)械工程學(xué)報(bào);2015年21期

6 郭愛民;張學(xué)輝;朱海清;;安全閥關(guān)閉件表面粗糙度對密封性能影響研究[J];化工機(jī)械;2015年05期

7 王晶;;安全閥的分類與常見故障原因分析[J];民營科技;2014年04期

8 周長寶;萬廣偉;;電站安全閥密封面手工研磨技術(shù)研究[J];黑龍江科技信息;2014年09期

9 孔令新;波拉提·阿努爾拜克;;新型安全閥閥座研磨機(jī)構(gòu)研制[J];石油化工設(shè)備;2012年S1期

10 楊昌明;朱利;張冒;;研磨機(jī)研磨運(yùn)動軌跡分析[J];機(jī)床與液壓;2012年15期

相關(guān)碩士學(xué)位論文 前6條

1 閔加豐;安全閥在線校驗(yàn)關(guān)鍵技術(shù)研究[D];江南大學(xué);2014年

2 李鵬鵬;藍(lán)寶石的高效固結(jié)磨料研磨研究[D];南京航空航天大學(xué);2014年

3 孫國棟;聚晶金剛石高速研磨表面質(zhì)量及其影響因素分析[D];沈陽理工大學(xué);2013年

4 王謙;面接觸磨削材料去除機(jī)理與表面創(chuàng)成研究[D];天津大學(xué);2012年

5 樊佳朋;UNIPOL-802平面研磨機(jī)研磨軌跡的研究[D];東北大學(xué);2010年

6 黃晨;行星式精密球體高效研磨加工機(jī)理與工藝研究[D];浙江工業(yè)大學(xué);2008年

，

本文編號：1694459