本文選題：伺服轉(zhuǎn)塔刀架 + 故障模式與影響分析��； 參考：《東南大學(xué)》2016年博士論文

【摘要】：加速提升中高檔數(shù)控系統(tǒng)和功能部件配套能力,是順應(yīng)當(dāng)今數(shù)控機(jī)床高速、高效、高精、柔性和復(fù)合加工發(fā)展趨勢的重要任務(wù)。對數(shù)控刀架這一功能部件而言,伺服轉(zhuǎn)塔刀架(本節(jié)以下簡稱“伺服刀架”)是由中檔產(chǎn)品跨入高檔產(chǎn)品的橋梁,因此對該產(chǎn)品的自主研制具有承前啟后的意義。在這一新產(chǎn)品研發(fā)過程所應(yīng)對的關(guān)鍵技術(shù)指標(biāo)中,其可靠性水平將直接牽制所匹配機(jī)床的整體性能,特別是運(yùn)行穩(wěn)定性和工作效率,因此,基于可靠性系統(tǒng)工程的研發(fā)階段工作以研究并提升伺服刀架的可靠性水平,將具有重大的工程應(yīng)用價值。本文在“高檔數(shù)控機(jī)床與基礎(chǔ)制造裝備”科技重大專項資金項目的資助下,針對伺服刀架在研發(fā)階段的可靠性定性分析、定量評估、優(yōu)化設(shè)計、研制試驗(yàn)進(jìn)行了系統(tǒng)研究。研究過程中,通過綜合運(yùn)用可靠性技術(shù)體系,并根據(jù)伺服刀架自身特點(diǎn)創(chuàng)新性地提出了多狀態(tài)動態(tài)故障樹分析方法、多失效模式下多狀態(tài)頻率可靠性分析方法、刀架可靠性切削研制試驗(yàn)方法,以及基于綜合運(yùn)行信息的PCM-PHM綜合模型,探索出了一整套完整實(shí)用的解決方案,從而能有效評估并提升新研制伺服刀架的可靠性水平。概括起來,本文的研究內(nèi)容及取得的主要成果如下：(1)伺服刀架故障模式與影響分析(FMEA)。在系統(tǒng)規(guī)劃和原型設(shè)計階段,通過分析FMEA的目標(biāo)及實(shí)施步驟,特別指出收集相似產(chǎn)品的可靠性信息能有效提高FMEA結(jié)論的有效性；基于該思路統(tǒng)計分析了相似成熟產(chǎn)品液壓轉(zhuǎn)塔刀架的故障部位、故障模式；采用分布擬合檢驗(yàn)方法建立了系統(tǒng)及各子系統(tǒng)含截尾數(shù)據(jù)的首次故障時間模型�；讵�(dú)立功能流串聯(lián)/并聯(lián)/轉(zhuǎn)換規(guī)則將伺服刀架規(guī)范劃分為10個子系統(tǒng)模塊,并在此基礎(chǔ)上估計了與液壓轉(zhuǎn)塔刀架各個相似模塊元以及系統(tǒng)整體的相似度。以各個子系統(tǒng)為單位列舉了可能的故障模式及故障原因,結(jié)合故障影響分析,提出了預(yù)防及補(bǔ)償措施。(2)伺服刀架多狀態(tài)系統(tǒng)可靠性指標(biāo)分析。根據(jù)伺服刀架的多狀態(tài)特性,提出了多狀態(tài)動態(tài)故障樹(MDFT)建模分析方法：首先提出了狀態(tài)空間以及狀態(tài)變換的線性代數(shù)描述方法(LAR),并基于狀態(tài)變換的思路將各類靜、動態(tài)邏輯門運(yùn)算規(guī)則的建立轉(zhuǎn)化為兩個變量的求解。在此基礎(chǔ)上,針對模塊化的MDFT模型,提出了可變步長時序模擬時鐘的生成方法,以支持蒙特卡洛仿真定量分析多狀態(tài)特性下的系統(tǒng)可靠度及子系統(tǒng)重要度。將該方法應(yīng)用到伺服刀架中,評估出系統(tǒng)可靠壽命以及后續(xù)以待優(yōu)化的關(guān)鍵子系統(tǒng)。(3)伺服刀架關(guān)鍵結(jié)構(gòu)的可靠性優(yōu)化設(shè)計。在改進(jìn)設(shè)計階段,基于應(yīng)力-強(qiáng)度干涉模型建立了多失效模式下刀盤子系統(tǒng)狀態(tài)函數(shù),綜合運(yùn)用矩方法、蒙特卡洛仿真搭建了靜強(qiáng)度可靠性模型；采用可靠性靈敏度分析識別敏感結(jié)構(gòu)參數(shù),并優(yōu)選出滿足可靠度要求的改進(jìn)方案。提出了多失效模式下多狀態(tài)頻率可靠性分析方法,并設(shè)計了嵌套式蒙特卡洛仿真以評估系統(tǒng)頻率可靠度；采用相關(guān)性分析方法識別了隨機(jī)結(jié)構(gòu)參數(shù)的敏感程度和敏感方向；將該方法應(yīng)用到基于多體系統(tǒng)傳遞矩陣法(MS-TMM)所建立的伺服刀架系統(tǒng)動力學(xué)模型上,提出了輕量化設(shè)計方案使得系統(tǒng)頻率可靠度得到了顯著提高。(4)伺服刀架可靠性切削研制試驗(yàn)設(shè)計及試驗(yàn)平臺搭建。在樣機(jī)試制階段,綜合考慮伺服刀架的實(shí)際工況提出了刀架可靠性切削研制試驗(yàn)方法,以合理評估在真實(shí)切削載荷環(huán)境下的可靠性水平,所考察可靠性包含著刀架的性能保持能力：系統(tǒng)陳述了試驗(yàn)總體設(shè)計思路,并以功能需求為指導(dǎo)搭建了刀架綜合性能及可靠性研究平臺；提出了基于多種材料典型試件加工的任務(wù)剖面編制方法,使得借助切削力測試系統(tǒng)最終確定的試驗(yàn)內(nèi)容既具有代表性,又能流暢執(zhí)行以縮短試驗(yàn)周期；制定了綜合性能測試規(guī)程(包括靜剛度、重復(fù)定位精度、轉(zhuǎn)位噪聲、加速度頻響函數(shù)),以及數(shù)據(jù)采集分析方法。(5)基于綜合運(yùn)行信息的受試伺服刀架可靠性評估。針對具有突發(fā)類與退化類共存且相互獨(dú)立的競爭故障模式,以經(jīng)典協(xié)變量模型為基礎(chǔ)提出了PCM-PHM綜合模型：既考慮了載荷條件對不同類故障模式下可靠性的影響,又充分利用多種性能特征以建立退化類故障模式下的可靠性模型。將該方法應(yīng)用到參與可靠性切削研制試驗(yàn)的受試樣機(jī)可靠性評估中：采用恒值載荷步疊加計數(shù)及分布擬合檢驗(yàn)方法建立了試驗(yàn)載荷分布模型,并基于此確定了環(huán)境協(xié)變量；采用相關(guān)分析及指數(shù)模型建立起綜合響應(yīng)協(xié)變量特征值；利用多元線性回歸方法獲得了伺服刀架故障率函數(shù),并進(jìn)一步建立了可靠度函數(shù)及可靠壽命估計。上述研究成果最終應(yīng)用于伺服刀架的設(shè)計制造中,取得了良好的實(shí)際效果。這款具有自主知識產(chǎn)權(quán)的中高檔數(shù)控刀架功能部件產(chǎn)品目前已經(jīng)批量生產(chǎn)并實(shí)現(xiàn)與數(shù)控車床配套使用,其可靠性水平在用戶處得到了普遍認(rèn)可。
[Abstract]:It is an important task to accelerate the upgrading of middle and high grade CNC system and functional components. It is an important task to conform to the development trend of high speed, high efficiency, high precision, flexible and compound machining of CNC machine tools. For this function part, servo turret (hereinafter referred to as "servicing tool holder") is a bridge from middle grade to high-end products. In this new product R & D process, the reliability level will directly affect the overall performance of the matched machine tool, especially the operation stability and efficiency. Therefore, the research and development stage based on the reliability system engineering will be studied and The improvement of the reliability level of the servo tool holder will be of great engineering application value. In this paper, the reliability qualitative analysis, quantitative evaluation, optimization design and development test of the servo tool holder in the R & D stage are systematically studied under the support of the major project of "high-grade CNC machine tools and basic manufacturing equipment". In the process, the multi state dynamic fault tree analysis method, multi state frequency reliability analysis method under multi failure mode, tool reliability cutting development test method, and PCM-PHM integrated model based on comprehensive operation information are explored and explored, based on the comprehensive application of reliability technology system and according to the characteristics of servo tool frame. A complete set of practical solutions can be used to effectively evaluate and improve the reliability level of the newly developed servo tool holder. In summary, the research content and main achievements of this paper are as follows: (1) the failure mode and influence analysis (FMEA) of the servo tool holder. In the stage of system planning and prototype design, the objectives and implementation steps of the FMEA are analyzed. In particular, it is pointed out that the reliability information of collecting similar products can effectively improve the validity of the FMEA conclusion. Based on this idea, the fault location and fault mode of the hydraulic turret tool holder of similar mature products are analyzed and the fault time model based on the distribution fitting test method is used to establish the first fault time model of the system and each subsystem with truncated data. The independent functional flow series / parallel / conversion rules divide the servo tool frame into 10 subsystem modules, and on this basis, the similarity between the various modules and the whole system of the hydraulic turret tool is estimated. The possible failure modes and failure reasons are enumerated in each subsystem. Prevention and compensation measures. (2) reliability index analysis of multi state system of servo tool frame. Based on the multi state characteristics of servo tool frame, a multi state dynamic fault tree (MDFT) modeling and analysis method is proposed. First, the linear algebraic description method of state space and state transformation (LAR) is proposed, and all kinds of static and dynamic state transformation are based on the state transformation. The establishment of logic gate operation rules is transformed into two variables. On this basis, a method of generating variable step size time series analog clock is proposed for modularized MDFT model, in order to support the Monte Carlo simulation for quantitative analysis of system reliability and subsystem importance in multi state characteristics. The method is applied to the servo tool frame and the evaluation of the method is applied. The reliable life of the system and the key subsystem of the subsequent optimization are estimated. (3) the reliability optimization design of the key structure of the servo tool. In the improved design stage, the state function of the knife and plate system under the multi failure mode is established based on the stress intensity interference model. The static strength reliability model is built by the Monte Carlo simulation and the Monte Carlo simulation. The reliability sensitivity analysis is used to identify the sensitive structural parameters and optimize the scheme to meet the requirements of reliability. A multi state frequency reliability analysis method under multiple failure modes is proposed, and a nested Monte Carlo simulation is designed to evaluate the reliability of the system frequency, and the random structural parameter is identified by the method of correlation analysis. The sensitivity and sensitive direction of the number are applied to the dynamic model of the servo tool frame system based on the multibody system transfer matrix method (MS-TMM). A lightweight design scheme has been proposed to improve the system frequency reliability significantly. (4) the experimental design and test platform of the servo tool holder can be developed and the test platform is set up. In the trial stage of the prototype, the reliability cutting test method of the tool holder is put forward in consideration of the actual working conditions of the servo tool holder, so as to reasonably evaluate the reliability level in the real cutting load environment, and the reliability is included in the performance retention capability of the tool holder. The system states the overall design idea of the test and takes the function requirement as the guidance. The research platform for comprehensive performance and reliability of the tool holder is built, and a task section compilation method based on the typical specimen processing is put forward, which makes the final test content of the cutting force testing system not only representative, but also can be carried out smoothly to shorten the test period. Complex positioning accuracy, transposition noise, acceleration frequency response function, and data acquisition and analysis methods. (5) the reliability evaluation of the servo tool holder based on the integrated operation information. The PCM-PHM synthesis model is proposed based on the classical covariate model, which is based on the classical covariate model. The effect of load conditions on the reliability of different type of fault modes and the full use of various performance characteristics to establish the reliability model of the degenerate type fault model. The method is applied to the reliability evaluation of the sample machine involved in the reliability cutting development test: the method of constant load step superposition counting and distribution fitting test is established. The experimental load distribution model is established, and the environmental covariate is determined based on this. The correlation analysis and the exponential model are used to establish the eigenvalue of the integrated response covariate, and the fault rate function of the servo tool holder is obtained by using the multiple linear regression method, and the reliability function and the life estimation are further established. The results are finally applied. In the design and manufacture of the servo tool, a good practical effect has been achieved. The product of the middle and high grade CNC tool rack with independent intellectual property right now has been produced and used with the CNC lathe. The reliability level has been universally recognized at the user's place.

【學(xué)位授予單位】：東南大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：TG659
，

本文編號：1806543