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1、學校代碼:11517 學 號:3 HENAN INSTITUTE OF ENGINEERING 文獻翻譯 題 目 110kv變電站設計 學生姓名 褚?guī)浄?專業(yè)班級 電氣工程及其自動化1021班 學 號 3 系 (部) 電氣信息工程系 指導教師(職稱) 任鵬飛 完成時間 2012年 2月 18日 一種實用的輸配電系統(tǒng)的維護優(yōu)化計劃Sohrab Asgarpoor Mohamad Doghman Department of Electrical Engineering Principal Research Engineer University of Nebraska-Lincoln Omaha
2、Public Power Distric摘要:今天,維護和/或提高系統(tǒng)的可靠性和降低運營和維護(OM)成本是電力的首要任務。由于系統(tǒng)設備繼續(xù)老化,并逐漸惡化,由于組件故障增加的服務中斷的概率。一個有效的維護策略是在提供安全可靠的電力客戶經(jīng)濟所必需的。本文的目的是提供一個預測,條件為基礎的框架,且成本有效的維護,輸電和配電系統(tǒng)的優(yōu)化方案。 引言原則上,提高系統(tǒng)的可靠性和降低運營和維護(OM)成本是電力的重中之重。在競爭日益激烈的電力輸送環(huán)境,電力公司被迫申請實用資產(chǎn)管理更加積極主動的方法。的電力交貨資產(chǎn)管理的主要組成部分之一,是資本預算和現(xiàn)有設施的OM。由于在許多情況下,建設和設備采購的成本是固
3、定的,澳M的支出為削減成本和潛在的儲蓄的主要候選人。由于系統(tǒng)設備繼續(xù)老化,并逐漸惡化,由于組件故障增加的服務中斷的概率。電力公司都面臨著許多挑戰(zhàn),在這種競爭的新時代:上升的OM成本,系統(tǒng)上的需求不斷增長,保持高可靠性和電能質(zhì)量水平和管理設備老化。因此,健康的設備是由設備條件的影響,因為收入行業(yè)至關重要。當需求高和設備的工作秩序,豐厚的收入可以實現(xiàn)的。相反,不健康的設備可能會導致服務中斷,顧客不滿,善意的損失,并最終失去客戶。提供安全可靠的電力客戶經(jīng)濟有效的維護策略是必不可少的。前二戰(zhàn)時期期間,產(chǎn)業(yè)是不是非常高度機械化,因此停機時間的影響并不十分顯著。此外,設備簡單容易解決,公司的表現(xiàn)主要是糾正
4、性維護(CM)。郵政第二次世界大戰(zhàn)期間,直到20世紀70年代中期的時代,提高機械化導致更紛繁復雜的設備。公司已開始大量依靠此設備。這種依賴導致的預防性維護(PM)的概念。下午,在1960年,主要包括在固定的時間間隔進行設備大修。此外,這臺設備的成本增加,導致管理開始尋找方法來提高這些資產(chǎn)的生命。最新的時代開始了與中航工業(yè)在早期到1970年代中期。在想,以確保設備持續(xù)盡可能長的正確和經(jīng)營的企業(yè)造成新的高度機械化設備的巨額費用。這個時代,也標志著在提高安全意識(尤其是在航空業(yè))和環(huán)境后果。越來越多,發(fā)生故障的安全或環(huán)境的危害。所有這一切導致的維修費用的增加。在某些行業(yè),維護成本代表的第二個最高甚至
5、經(jīng)營成本最高的組件。維護策略在一般情況下,維護計劃或無計劃.糾正性維修是一種被動的戰(zhàn)略,這是無計劃和故障發(fā)生后,正在開展。我們的目的是恢復一個項目到一個國家能夠履行其所需的功能。計劃中的維護策略在本質(zhì)上是積極的,可分為兩組:預防和狀態(tài)監(jiān)測。有時也被稱為預定的預防性維護,定期進行維護。這個類別下,可以選擇有四個基本任務:時間導演的任務涉及到的操作數(shù),工作時間,或季節(jié)性變化。b)未能發(fā)現(xiàn)是用于識別設備故障不屬于明顯的經(jīng)營人員(隱性故障)。通常用于保護設備。C)條件導演適用的情況時,設備條件達到了一個極限,或者續(xù)令人滿意操作時不能保證。它可以防止早期失效,成為真正的失敗。D)運行故障是一個選擇的選項
6、,只有在不能確定的事件,技術(shù)上是正確的,符合成本效益的任務。當它認為有必要的基礎上定期檢查,診斷測試或其他狀態(tài)監(jiān)測手段,進行了預測性維修(PDM)。狀態(tài)監(jiān)測是用來預測設備故障監(jiān)測或診斷活動。4。以可靠性為中心的維修(RCM)在20世紀60年代末,中航工業(yè)在生產(chǎn)第一“的大型噴氣式客機”的邊緣。新747的三倍大小ofany目前在空氣中的其他客機。 747,新的發(fā)動機,其結(jié)構(gòu),航空電子設備,并像所有聯(lián)邦航空管理局(FAA)最初采取的立場,即747預防性維護將是非常廣泛的,很多技術(shù)進步公認的大小 - 如此廣泛,事實上,航空公司不可能在一個有利可圖的方式經(jīng)營這架飛機。這個問題導致飛機制造業(yè)完全重新評估它
7、的PM計劃。是什么導致這方面的努力是一種全新的方式,聘請排名PM任務,必要時要保留的關鍵飛機飛行3功能決定樹的過程。這項新技術(shù),最終由美國聯(lián)邦航空局的批準,不久發(fā)展到什么是已知的可靠性為中心的維修(RCM)的。德盛導致主要勞動力,原材料成本和庫存成本降低航空業(yè)使用。此外,它適用于在1980年的核電產(chǎn)業(yè)。今天,RCM是許多行業(yè),包括電力行業(yè)選擇的維修技術(shù)。優(yōu)點是能夠與制造商合作,創(chuàng)建一個為新一代設備的RCM方案不同的是航空業(yè),公用事業(yè)行業(yè),尤其是發(fā)電行業(yè),已采取作為一個歷史悠久的修改德盛現(xiàn)有電廠的維修方法4 。盡管在“中游”德盛計劃的實施有關的費用,他們已經(jīng)發(fā)現(xiàn)自己在很短的時間內(nèi)支付。 RCM,
8、已被主要應用于核電廠,往往需要最大的維修量,因為安全和環(huán)境方面的考慮。然而,這些成功的方案現(xiàn)在經(jīng)營,化石發(fā)電廠和輸電和配電系統(tǒng),最近已進入混合。因為這些設施都面臨著一個不太嚴格的監(jiān)管環(huán)境,他們應該能夠直接適用簡化RCM的形式更容易,從而降低了實施成本。 改造維修方案的第一步是要落實在RCM的方法whichwill幫助建立一個新的方案的優(yōu)先次序。具體來說,RCM是一套旨在幫助一個實用程序來確定一套最低限度的預防性維修任務,要妥善處理關鍵設備故障不影響服務的可靠性的方法和工具。 RCM是一種結(jié)構(gòu)化的過程,在一個特定的經(jīng)營環(huán)境,以確定最佳的設備維護要求。它結(jié)合了糾正性維護,預防性維護和預測性維護策略
9、,并適用于這些策略是適當?shù)?,其中每個功能失敗的后果和頻率的基礎上。這種結(jié)合產(chǎn)生的維修計劃,優(yōu)化可靠性和成本效益。對于重大件設備,電力變壓器,如RCM可能表明,預測性維修是一個有吸引力的選擇,傳感器和診斷技術(shù)和運行設備故障增加了成本的降低成本。 RCM是一個基于條件的維護計劃,重點是防止有可能是最嚴重的失敗。 RCM和預測維修(PDM)的分析相得益彰,當它們同時執(zhí)行,維護優(yōu)化提供了一個極好的方法。在過去的幾年中,監(jiān)測設備市場上的成熟,電子和計算機的價格下降了現(xiàn)場監(jiān)測應用具有成本效益的現(xiàn)實。可以很容易解釋的基本概念和基本原則的RCM。其主要方法可以歸結(jié)為以下四點:1)保護系統(tǒng)功能2)確定主要失效模
10、式3)優(yōu)先功能的需求,使預算可以集中保存最關鍵的功能4)選擇只適用和有效的維護任務RCM的一些好處是:1)減少主要整改措施2)消除不必要的大修和日常工作提供一點好處3)優(yōu)化的頻率所需的大修4)提高預測技術(shù)的使用,幫助與資源規(guī)劃5)減少使用侵入性的任務,可誘發(fā)設備故障6)提高日常工作的成本效益7)創(chuàng)建記錄的維修方案的技術(shù)基礎8)允許納入現(xiàn)有的維護,已被證明是具有成本效益的做法,容易實施9)過程的知識,通信和團隊精神正在開發(fā)廉價的固態(tài)傳感器,例如,可以插在變壓器油檢測的保溫開始惡化時,產(chǎn)生的氣體的存在。一旦信息變得可預測性維護技術(shù),它需要與來自全國各地電力網(wǎng)絡,并從歷史記錄上線的數(shù)據(jù)集成。5。新技
11、術(shù) 有許多技術(shù)可用的今天,一些新的方法正在調(diào)查,以確定設備狀態(tài)5。以下僅僅是用于監(jiān)測電力傳輸設備的幾個應用程序: 超聲波噪聲分析局部放電檢測該技術(shù)采用電傳感器檢測絕緣子和終止,如電氣設備的初始絕緣擊穿。局部放電檢測是用來檢測重大損害發(fā)生前的早期故障。變壓器油天然氣分析這是必要的,以保持變壓器上線盡可能。異常的指標之一是在變壓器油中溶解氣體的含量。某些氣體含量可以表明老化,需要維修,或潛在的故障。紅外熱成像熱調(diào)查涉及紅外攝像機的使用在電廠使用的大型電機檢測熱點。聲音強度測量聲強計需要找出潛在的問題,在設備和錄制的聲音和輸出設備的歷史變遷 對于輸電和配電系統(tǒng),如變壓器故障氣體分析儀的傳感器可能被證
12、明是有益的。此設備提供實時測量變壓器故障電流的四個關鍵氣體:一氧化碳,氫氣,乙炔和乙烯。下一步是把一個額外的傳感器檢測水分的存在,從而可降低介電強度和導致失敗。這將被用來測量變壓器負載,使負載的功能特點,演化的關鍵氣體和水分可以作為與其他設備。隨著濕度傳感器和負載電流監(jiān)視器,我們可以開發(fā)加載壓力條件下的變壓器,而不是依靠現(xiàn)在提供了過于保守的評級準確的標準。6.擬議的綜合方法輸電和配電系統(tǒng)的集成方法,將確保導致為一個特定的負載設備或子系統(tǒng),在各部門的維修水平將得到統(tǒng)一和一致,從而提升和優(yōu)化維修過程。為了建立一個維修方案,RCM過程大概需要是驅(qū)動點。圖2顯示為維護優(yōu)化方案需要不同的策略。經(jīng)典的RC
13、M過程包括識別系統(tǒng)進行研究,他們的功能,功能故障,故障模式,故障原因,維修任務選擇。 需要確定設備最關鍵部分,從而影響系統(tǒng)的整體功能。換句話說,我們需要識別設備時失敗的嚴重后果。此外,關鍵客戶和領先的負載設備需要確定。影響這些客戶的所有設備都需要進行分析,并應確定設備的最關鍵部分。我們還需要了解客戶在可靠性,安全性,電能質(zhì)量,成本等方面的需要,這些屬性必須加權(quán),以確定最佳的維護策略與這些客戶打交道。 為了優(yōu)化公用事業(yè)維修計劃,所有相關信息,必須使用最有效的啟動,計劃,跟蹤,記錄,分析維護任務。一個開放的通訊協(xié)議,使各種監(jiān)控設備(不管制造商)與utilityoffices,互相交談,并與控制中心
14、,最適合電力的需求,通過整合各種數(shù)據(jù)源和其他軟件模塊。 目前,許多大型公用事業(yè)機構(gòu)執(zhí)行一些診斷測試設備。許多電腦他們的維修工作,包括保留維護的歷史,記錄重要的業(yè)務活動,維護設備的設計資料庫管理功能。適當?shù)臏贤ǎ虾头治鏊羞@些信息將導致更準確的建議,關于何時執(zhí)行維護和/或特定的設備如何操作。在同行業(yè)中的一個典型的問題是,在次,收集大量的數(shù)據(jù),但它沒有集成和處理方便快速評估。無法在此結(jié)果使直接Mrecommendations的,而未能提供成本效益可能已經(jīng)實現(xiàn),therebyadding數(shù)據(jù)收集的成本。 其他,可能有助于維護改善的因素是:保持設備的健康廉價的傳感器技術(shù)和有效的診斷中的應用;數(shù)據(jù)從
15、多種分析和決策的來源協(xié)調(diào);橫跨和變電站的信息有效的交流制度;和經(jīng)驗池的訓練有素的專業(yè)人員。應編制管理工作人員和硬件/軟件的投資,積極管理維護計劃。一個團隊的方式到德盛必須保留和RCM的概念,必須在組織所接受。 為了使用適當?shù)能浖陀布?,教育和培訓工作應該是這一進程的一個組成部分。必須保證實用的維修方案和工作經(jīng)驗的工作人員所需的工具的基本知識的理解。維持一個成功的維修計劃的關鍵是發(fā)展進程的很長一段時間,這將確保維護計劃的延續(xù)。這是必要的定期審查和更新維護方案,使用結(jié)構(gòu)化的方法。7。結(jié)論 今天,降低運營和維護成本和維護服務的可靠性,實用輸電和配電系統(tǒng)的管理者的首要任務。 RCM的概念是健全的,應提
16、供一個結(jié)構(gòu)化的方法與維修維護和可靠性改進的成本之間的最佳平衡方案的事業(yè)。 RCM和PDM分析相得益彰,并同時進行時,提供一個很好的方法來維護的優(yōu)化。參考文獻1 G. J. Anders, Probability Concepts in Electric Power Systems, 1990, John Wiley & Sons. 2 J. Moubray, Reliability-Centered Maintenance, Industrial Press Inc., 1992. 3 A. M. Smith, Reliability-Centered Maintenance, McGraw-
17、Hill Book Co., 1993. 4 S. Asgarpoor and C. Singh, “Methods for Detection of Equipment Aging and Incorporating it in the Reliability Analysis”, Proceedings of NSF Symposium on Electric Power Systems Infrastructure, Pullman, WA, October 1994. 5 J. Douglas, “The Maintenance Revolution”, EPRI Journal, V
18、ol. 20, No. 3, May/June 1995, pp. 6-15.A Maintenance Optimization Program for Utilities Transmission and Distribution Systems Sohrab Asgarpoor Mohamad Doghman Department of Electrical Engineering Principal Research Engineer University of Nebraska-Lincoln Omaha Public Power Distric ABSTRACT: Today, p
19、reserving and/or enhancing system reliability and reducing operations and maintenance (O&M) costs are top priorities for electric utilities. As system equipment continue to age and gradually deteriorate, the probability of service interruption due to component failure increases. An effective mainten
20、ance strategy is essential in delivering safe and reliable electric power to customers economically. The objective of this paper is to provide a framework for a predictive, condition-based, and cost effective maintenance optimization program for transmission and distribution systems. 1. INTRODUCTION
21、 In principle, improving system reliability and reducing Operations and Maintenance (O&M) costs are top priorities of electric utilities. In an increasingly competitive power delivery environment, electric utilities are forced to apply more proactive methods of utility asset management. One of the m
22、ain components of electric power delivery asset management is the capital budgeting and O&M of existing facilities. Since in many cases the cost of construction and equipment purchases are fixed, O&M expenditures is the primary candidate for cost cutting and potential savings. As system equipment co
23、ntinue to age and gradually deteriorate, the probability of service interruption due to component failure increases. Electric utilities are confronted with many challenges in this new era of competition: rising O&M costs, growing demand on systems, maintaining high levels of reliability and power qu
24、ality, and managing equipment aging. Therefore, the health of equipment is of utmost importance to the industry because revenues are affected by the condition of equipment. When demand is high and equipment is in working order, substantial revenues can be realized. On the contrary, unhealthy equipme
25、nt can result in service interruption, customer dissatisfaction, loss of good will, and eventual loss of customers. An effective maintenance strategy is essential to delivering safe and reliable electric power to customers economically.2.MAINTENANCE During the Pre-World War II era, industry was not
26、very highly mechanized, therefore the impact of down time was not very significant 2. Also, equipment was simpler which made it easy to fix, and companies performed mainly Corrective Maintenance (CM). During the Post-World War II until the mid 1970s era, increased mechanization led to more numerous
27、and complex equipment. Companies were beginning to rely heavily on this equipment. This dependence led to the concept of Preventive Maintenance (PM). In the 1960s, PM consisted mainly of equipment overhauls done at fixed intervals. Also, the increased costs of this equipment led management to start
28、finding ways to increase the life of these assets. The latest era began with the aircraft industry in the early to mid 1970s. The huge costs of new highly-mechanized equipment resulted in companies wanting to ensure that equipment lasted and operated correctly for as long as possible. This era also
29、marked an increased awareness in safety (especially in the airline industry) and environmental consequences. Increasingly, occurrence of failures represent safety or environmental hazards. All of this has led to an increase in the cost of maintenance. In some industries, maintenance costs represent
30、the second highest or even the highest component of operating costs.3.MAINTENANCE STRATEGIES In general, maintenance is either planned or unplanned as shown in Figure 1. Corrective maintenance is a reactive strategy which is unplanned and is carried out after failure has occurred. The intention is t
31、o restore an item to a state that can perform its required function. Planned maintenance strategies are proactive in nature and can be divided into two groups: Preventive and Condition Monitoring. Preventive maintenance which is sometimes called scheduled, is a maintenance carried out at regular int
32、ervals. There are four basic tasks that can be selected under this category:Time Directed task involves number of operations, operating hours, or seasonal change.Failure Finding is for identifying equipment failure that are not evident to the operating crew (hidden failures). Usually used for protec
33、tive equipment. Condition Directed applies to the situation when the condition of equipment reaches a limit, or when continued satisfactory operation can not be ensured. It prevents incipient failure from becoming real failure. Run To Failure is an option that is selected only in the event that a te
34、chnically correct and cost-effective task can not be identified. Predictive Maintenance (PdM) is carried out when it is deemed necessary, based on periodic inspections, diagnostic tests or other means of condition monitoring. Condition Monitoring is the monitoring or diagnostic activity that is used
35、 to predict equipment failure. 4.RELIABILITY CENTERED MAINTENANCE (RCM) During the late 1960s, the aircraft industry was on the verge of manufacturing the first “jumbo jets”. The new 747s were three times the size ofany other passenger jets currently in the air. The recognized size of the 747, its n
36、ew engines, and its many technology advances in structures, avionics, and the like, all led to Federal Aviation Administration (FAA) to initially take the position that preventive maintenance on the 747 would be very extensive so extensive, in fact, that the airlines could not likely operate this ai
37、rplane in a profitable fashion. This problem led the aircraft industry to completely reevaluate its PM program. What resulted from this effort was a whole new approach that employed a decision-tree process for ranking PM tasks that were necessary to preserve critical aircraft functions during flight
38、 3. This new technique was eventually approved by the FAA and soon thereafter evolved into what is known as Reliability Centered Maintenance (RCM). RCM used by the airline industry led to major reduction in labor, material cost and inventory cost. Further it applied to nuclear power industry in the
39、1980s. Today, RCM is the maintenance technique of choice for many industries including power industries. Unlike the airline industry which had the advantage of being able to work with manufacturers to create an RCM program for a new generation of equipment, the utility industry, especially the elect
40、ric power generation industry, has had to adopt RCM as a modification of long-established maintenance practices at existing plants 4. Despite the costs associated with the implementation of these RCM programs in “midstream”, they have been found to pay for themselves in very short order. RCM, as has
41、 been mainly applied to nuclear power plants, often requires the largest amount of maintenance because of safety and environmental considerations. However, with these successful programs now operating, fossil power plants and power transmission and distribution systems have recently been getting int
42、o the mix. Because these facilities face a less restrictive regulatory environment, they should be able to directly apply the streamlines forms of RCM much more easily, thus reducing the implementation costs. The first step in revamping a maintenance program is to implement an RCM approach whichwill
43、 help establish priorities for a new program. Specifically, RCM is a set of methods and tools aimed at helping a utility to determine the minimum set of preventive maintenance tasks necessary to appropriately address critical equipment failures without compromising service reliability. RCM is a stru
44、ctured process used to determine optimal maintenance requirements for equipment in a particular operating environment. It combines the strategies of corrective maintenance, preventive maintenance and predictive maintenance, and applies these strategies where each is appropriate, based on the consequ
45、ence and frequency of functional failures. This combination produces a maintenance program which optimizes both reliability and cost effectiveness. For major pieces of equipment, such as power transformers, RCM may indicate that predictive maintenance is an attractive option, given the decreasing co
46、st of sensor and diagnostic technology and the increasing cost of running the equipment to failure. RCM is a condition-based maintenance program that focuses on preventing failures that are likely to be the most serious. RCM and Predictive Maintenance (PdM) analyses complement each other, and when t
47、hey are performed concurrently, offer an excellent approach to maintenance optimization. In the last few years, the sophistication of monitoring equipment on the market and the falling price of electronics and computers have made the on-site monitoring applications a cost effective reality. The very
48、 basic concepts and underlying principles of the RCM can be explained very easily. Its main methodology can be reduced to the following four points:1) preserve system functions 2) identify dominant failure modes 3) prioritize function needs so that budget can be focused on preserving most critical f
49、unctions 4) select only applicable and effective maintenance tasks Some of the benefits of RCM are:1) Reduces major corrective actions 2) Eliminates unnecessary overhauls and routine tasks that provide little benefits 3) Optimizes the frequency of required overhauls 4) Increases use of predictive te
50、chnology that help with resource planning 5) Decreases use of intrusive tasks that can induce equipment failures 6) Improves cost-effectiveness of routine tasks 7) Creates documented technical bases for maintenance programs 8) Allows easy implementation by incorporating existing maintenance practice
51、s that have proven to be cost-effective 9) Processes Knowledge, communications, and teamwork Inexpensive solid state sensors are being developed, for example, that can be inserted in transformer oil to detect the presence of gases produced when insulation begins to deteriorate. Once the information
52、from predictive maintenance technology becomes available, it needs to be integrated with on-line data from across a power network and from historical records.5.NEW TECHNOLOGIES There are many technologies available today, and several new methods are being investigated to determine the equipment cond
53、ition 5. The following are just a few applications for monitoring power delivery equipment: Ultrasonic Noise Analysis The presence of tones in the ultrasonic range can be an indication of leaks of air, gas, steam, and vacuum. Ultrasonic noise can be emitted as a result of friction between moving par
54、ts. Partial Discharge Detection This technology employs an electrical sensor to detect the initial insulation breakdown in electrical equipment such as insulators and terminators. Partial discharge detection is used to detect incipient failures before significant damage occurs. Transformer Gas-in-Oi
55、l Analysis This is needed to keep the transformer on-line as much as possible. One indicator of abnormalities is the dissolved gas content in the transformer oil. Certain gas levels can indicate aging, the need for maintenance, or potential failure. Infrared Thermography Thermography surveys involvi
56、ng the use of an infrared camera to detect hot spots in large motors used in power plants. Sound Intensity Measurement Sound Intensity Meter is needed to identify potential problems in equipment and record the historical changes in sound and output of equipment For transmission and distribution syst
57、ems, sensors such as transformer fault gas analyzer might prove to be beneficial. This device provides real-time measurement of the four key gases associated with fault currents in transformer: carbon monoxide, hydrogen, acetylene, and ethylene. The next step is to incorporate an additional sensor to detect the prese
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