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Analysis of transformation of numerical control machine tool
In order to survival and development of enterprises, improve the rate of CNC machine tools is necessary. Transformation of the equipment needed for NC machine tools in general, including traditional and recently introduced from abroad, due to a problem can not be put into the machine tool equipment and production lines.
First, transform the contents of the NC
CNC machine tools and production line transformation of the main contents are: (1) restoration of the original function, machine tools, production lines there is some fault diagnosis and recovery; (2) NC-based, in the general machine tools addend remarkable device or add numerical control system; ( 3) The renovation, to improve accuracy, efficiency and degree of automation, mechanical, electrical parts of the renovation, the mechanical part of the re-assembly process, to restore the original precision; can not meet the production requirements of its CNC system be updated with the latest CNC; (4) technology updates or technical innovation, in order to improve performance or grade, or for the use of new technology, new technology, based on the original large-scale technology updates or technical innovation.
Second, the development trend of CNC system
l. To open, the sixth generation of PC-based direction
The openness of the PC-based, low-cost, high reliability, rich in natural resources such as hardware and software features, and more CNC system manufacturer will be to go down this path. At least with PC, as its front-end machines, to deal with man-machine interface, programming, networking and communications issues, the original system to take over some tasks PC CNC machines has the friendly interface, will reach all of the CNC system. The remote communication, remote diagnostics and maintenance of applications will be more common.
2. To the development of high-speed and high precision.
3. To the intelligent direction
(1) The application of adaptive control technology. Numerical control system can detect the process of important information and automatically adjust system parameters, improving the system operation status.
2) the introduction of expert systems to guide processing. Will be skilled workers and expertise, processing and general laws and special laws into the system to process parameter database support, establish an artificial intelligence expert system.
(3) the introduction of fault diagnosis expert system
(4) intelligent digital servo drives. Can automatically identify the load and automatically adjust the parameters of the drive system to get the best state of operation.
Third, the choice of numerical control system
1. Open-loop system
The system's servo-driven device is a stepper motor, power stepper motors, electro-hydraulic pulse motors. This system does not require position and velocity feedback, displacement accuracy depends mainly on the angular displacement precision stepper motor and gear drive components such as precision screw, so displacement of low accuracy. But the system is simple, debugging easy maintenance, reliable, low cost, easily converted successfully.
2. Closed-loop system
The system consists of grating, sensor position detection device synchronization, etc. The actual measured position signal fed back to the computer, compared with a given value, the difference between the two amplification and transformation, driving the implementing agencies in order to eliminate bias. The system complexity, high cost and strict temperature requirements on the environment. But the system of high precision, speed and big power. According to technological requirements and decide whether to adopt.
3. Semi-closed-loop system
Semi-closed-loop system detects components installed in the middle of transmission parts, the indirect measurement of the location of the implementation of parts. It can only compensate for part of the components within the system loop error, and therefore its more accurate than the accuracy of closed-loop system is low, but its structure and debugging as compared with the closed-loop system is simple.
Current production numerical control system are more companies and manufacturers, foreign companies such as Siemens of Germany, Japan, Fanuc, Inc.; domestic Everest companies such as China, the Beijing Aerospace CNC System Corporation, Huazhong CNC CNC high-grade corporate and Shenyang National Engineering Research Center. Select CNC systems are mainly based on numerical control after transformation to be achieved in a variety of precision machine tools, drive motor power and the user's requirements to determine.
Fourth, the main steps CNC transformation
1. Determination of rehabilitation programs
(1) Mechanical and Electrical Repair transformation combined. Generally speaking, in need of transformation of electrical machines, are in need of mechanical repair. To determine repair requirements, scope and content; have to ascertain the electrical modification of the mechanical structure in need of transformation requirements and content; but also determine the transformation of electrical and mechanical repair, reconstruction staggered between the time requirements. Mechanical properties of intact are electrical transformation success.
(2) the easier issues first, after the first partial overall. Determine the transformation step, the whole electrical part of the transformation should be divided into several sub-systems, the basic shape of various systems to be connected after the completion of the whole system work. In each subsystem, we should do first the less technical, workload the larger work, and then do a technical high, requiring fine work, can focus people's attention to key areas.
(3) selection system under conditions of use. For the transformation of the object to determine its environment and conditions, which the selection of electrical system protection, anti-jamming, self-cooling and air filtering performance can provide the correct basis. Electrical system options must also be considered mature products, their performance should be reasonable and practical, there are spare parts to provide maintenance support, features a number of years to meet the current and future development requirements.
(4) The implementation and responsibilities of personnel involved in reconstruction.
(5) The transformation of the determination of the scope and cycle.
2. Transformation of the technical preparation
(1) mechanical parts ready. In line with the transformation of mechanical electrical repairs should be completed in advance. The same time, be demolished and replaced and processing should be part of such advance planning is necessary to properly interface with the entire transformation.
(2) The electrical information on the new system to digest.
(3) The conversion of the old system interface design. According to the scope of each of the different equipment modification required to pre-designed interface, part of the conversion, if the entire transformation should be designed to convert mechanical and electrical interfaces, operation panel control and configuration, the Internet part of the contact, parameter measurement, the maintenance and so on. Require the operation and maintenance easy and reasonable, alignments, fluent, primary and secondary connection point less electrical interference with the strength of the smallest, with an appropriate margin and so on. Local transformation, but also need to consider the performance of the system match the old and new, the voltage polarity and size of change, the installation location, digital-analog conversion, etc., if necessary, need to create their own interfaces.
(4) operation and programming staff technical training. ① training should cover the new control panel configuration, function and meaning of the instructions; ② the scope of the new system features, use, and the difference between the old system; ③ maintenance requirements; ④ programming standards and automated programming and more. Focused understood, grasp operating instructions and programming instructions.
(5) Debugging steps and acceptance criteria for the determination. Debugging should be done by the project leader carried out with the others. Debugging step can be from simple to complex, from small to large, from outside to inside, you can also after the first local situation, the whole system after the first subsystem. The development of acceptance criteria must be realistic, too high or too low a standard will have a negative impact on the transformation.
3. The implementation of reform
(1) The overall maintenance of the machine. The long-term use of the original machine, you need to conduct a comprehensive maintenance. Secondly, the response to machine tools to make a change before the geometric accuracy, dimensional accuracy of measurement, and for the record. In this way pairs of reference to guide the transformation of the role, but also in the transformation of the end for comparison analysis.
(2) to retain the electrical adjustment of some of the best. If the electrical system as part of the transformation, in turn, should retain the parts of the maintenance and optimization adjustments, such as high power part of the spare parts replacement, electrical maintenance, drying transformer insulation, pollution, cleaning, ventilation and cooling equipment cleaning, servo Drive optimization adjustments, update aging wires and cables, connectors and other fastening. Only the electrical part of the reservation and do excellent optimization adjustment, in order to ensure that transformed the machine tool have lower failure rates.
(3) The original systems were dismantled. The removal of the original system must be controlled carefully to the original drawings in time to make mark in the drawings to prevent the omission or been demolished. In the process of demolition will find some of the new system design in the gaps, it is timely to add and correction. Removed the system should be properly safeguarded in case of unsuccessful reconstruction resume use. There is a definite value, and can be used for spare parts.
(4) reasonable arrangements for the location and wiring the new system. Connection must be a clear division of labor, there is one person review the inspection to ensure that the connection process specifications, diameter suitable, correct, reliable and beautiful.
(5) debugging. Debug must be pre-established procedures and requirements. Debugging the first to test the safety protection system sensitivity, personal and equipment to prevent accidents. Debugging the site must be clean; the moving coordinate extension units at the center of the whole trip; be able to load test, the first no-load after load; can simulate the experiment, the first real action after simulated; be manual, first manually and automatically.
4. Acceptance and post-work
(1) The mechanical properties of machine tool acceptance. Machine tool should meet the requirements of the mechanical properties, geometric accuracy should be within the limits prescribed.
(2) The electrical control functions and control accuracy and acceptance. The various functions of electrical control actions must meet the normal, sensitive and reliable. Control precision application system itself functions (such as step size, etc.) and standard measuring apparatus (such as laser interferometer, coordinate measuring machine, etc.) control checks, to reach within a range. Should also be modified before the machine with the functions and accuracy to make comparison, access to quantifiable indicators of difference.
(3) The test piece cutting and acceptance. Can refer to the relevant domestic and international standards for CNC cutting specimens, in a qualified operator, the programmer with the trial under the cut. Specimen cutting machine tools can be acceptance of stiffness, cutting force, noise, motion trajectory, related actions, are generally not suitable for specimen use of a product part.
(4), drawings, information and acceptance. Machine transformation finished, should be promptly drawings, data, transform the file summary, collate, transfer into the file. This is the future and stable operation of the equipment is very important.
(5) Summary and improve.
5, numerical examples of reconstruction
1. Milling machine with the Siemens 810M transformation X53
In 1998, the company invested 200,000 yuan, with Germany's Siemens 810M CNC system, 611A AC servo drive system on the company's X53 model of a milling machine to X, Y, Z three-axis numerical control transformation. Retained the original spindle system and cooling system. -Axis transformation of a ball screw used in the machinery and gear transmission mechanism. The transformation of work includes mechanical design, electrical design, PLC program preparation and debugging, machine tool repair, machine installation and debugging. After transformation, milling, processing and effective travel X, Y, Z axis respectively, 880mm, 270mm, 280mm; maximum speed of X, Y, Z axis respectively, 5 000mm/min, 1 500mm/min, 800mm/min; point moving speed of X, Y, Z axis respectively 3 000mm/min, 1 000mm/min, 500 mm / min; machining accuracy of ± 0.001 mm. Machine tools, coordinate linkage to be completed by a variety of complex curve or surface processing.
2. GSK980T and stepper drive system with the transformation of C6140 lathe
In 1999, the company invested 8 million yuan, with Guangzhou CNC Equipment Factory production GSK980T numerical control system, DY3 hybrid stepper drive unit on the company's a longer C6140 lathe X, Z 2-axis transform. Retained the original spindle system and cooling system. Transformation of two-axis ball screw in the machinery used, and synchronous transmission. The transformation of work includes mechanical design, electrical design, machine overhaul and machine installation and debugging. Lathe After the transformation, processing and effective stroke X, Z axis respectively, 390mm, 1400mm; maximum speed X, Z axis respectively, 1 200mm/min, 3 000mm/min; jog speed 400mm/min; point moving fast X, Z-axis respectively, 1 200mm/min, 3 000mm/min; machine smallest mobile unit 0.001mm.
6, numerical transformation of the issues and recommendations
1. Transformation problems in NC
CNC machine tools through several transformation and found work, there are also many problems, mainly reflected in: (a) The departments, developers uncertain functions, organizational chaos, a serious impact on progress in the transformation; (2) to develop the work process and plans are mostly developed rule of thumb, less reasonable; (3) the training of relevant personnel is not in place, resulting in machine tool technology officers will not be modified after programming, the operator of the machine operator unskilled and so on.
2. Transformation of the proposed NC
(1) is responsible for transformation of the staff responsibilities of clear penalties and rewards, fully mobilize the enthusiasm of the staff; train a batch of high-quality applications and maintenance personnel, training for selected officers to go out and learn the advanced technologies;
(2) To focus on users, maintenance of CNC system of technical training, the establishment of numerical control technology at home and abroad resource library. The establishment of technical data files, do the work of spare parts.
分析數(shù)控機床改造
為了我國民營企業(yè)的生存與發(fā)展,提高數(shù)控機床的速度是必要的。轉(zhuǎn)型所需的設備一般數(shù)控機床,包括傳統(tǒng)和最近從國外引進的一個問題,由于不能放入機床設備和生產(chǎn)線。
首先,數(shù)控機床和生產(chǎn)線改造的主要內(nèi)容為:(1)恢復原有的功能、機床、生產(chǎn)線有一些故障診斷和恢復;(2),NC-based一般機床設備或添加加數(shù)顯著數(shù)控系統(tǒng);(3)改造,提高精度、效率和自動化程度,機械,電氣部件的改造、機械部分的維護過程中,才能恢復到最初的辨識精度,不能滿足生產(chǎn)要求的數(shù)控系統(tǒng)被更新到最新的數(shù)控;(4)技術更改或技術創(chuàng)新,以提高性能和品位,或使用新技術、新工藝、新技術,基于最初的大型技術更改或技術創(chuàng)新。
第二,數(shù)控系統(tǒng)的發(fā)展趨勢
l.開放、第六代基于pc機的方向
基于pc的開放性、低成本、高可靠性、豐富的自然資源,例如硬件和軟件數(shù)控系統(tǒng)的特點,并將更多廠商下去這條路。至少,作為它的前端與PC機,處理人機界面,編程,網(wǎng)絡和通信問題,將原系統(tǒng)接管一些任務電腦數(shù)控機床具有界面友好、將達到所有的數(shù)控系統(tǒng)。遠程通信、遠程診斷和維護程序?qū)懈嗟墓餐帯?
2.高速的發(fā)展,計算精度高。
3.向智能化方向發(fā)展
(1)自適應控制技術的應用。數(shù)控系統(tǒng)可以檢測過程中重要的情報,自動調(diào)整系統(tǒng)參數(shù),提高整個系統(tǒng)的運行狀況。
(2)引入專家系統(tǒng)來指導加工。將技術工人和專業(yè)知識、加工和一般規(guī)律和特殊規(guī)律進入系統(tǒng)工藝參數(shù)數(shù)據(jù)庫支持,建立一個人工智能專家系統(tǒng)。
(3)引入故障診斷專家系統(tǒng)
(4)智能數(shù)字伺服驅(qū)動器?？梢宰詣幼R別的熱負荷及自動調(diào)整參數(shù)的驅(qū)動系統(tǒng)獲得最佳的經(jīng)營狀況。
第三,選擇不同的數(shù)控系統(tǒng)
1.開環(huán)系統(tǒng)
系統(tǒng)的servo-driven裝置是一個步進電機、電力,電液步進電機脈沖馬達。這個系統(tǒng)并不需要位置與速度反饋、位移精度主要取決于的精密步進電機角位移和齒輪傳動部件,如精密螺絲,所以位移精度低。但是系統(tǒng)簡單,調(diào)試維修方便、可靠、成本低、易于變現(xiàn)的成功。
2.閉環(huán)系統(tǒng)
該系統(tǒng)主要由光柵傳感器位置檢測裝置,同步等。現(xiàn)場實測位置信號反饋到計算機,相比之下,給定值之間的差異,這兩個放大與轉(zhuǎn)化;推動執(zhí)行機構為了消除偏見。該系統(tǒng)的復雜性,成本高,對環(huán)境溫度要求嚴格。但是系統(tǒng)精度高、速度和強國。根據(jù)工藝要求,并決定是否接受。
3.Semi-closed-loop系統(tǒng)
Semi-closed-loop偵測元件安裝在系統(tǒng)中,間接測量傳動部位的路徑實施部分。它只能夠彌補內(nèi)組件的一部分系統(tǒng)回路的誤差,因而它更精確的閉環(huán)系統(tǒng)的精度低,不過,其結構和調(diào)試與閉環(huán)系統(tǒng)是簡單的。
目前生產(chǎn)的數(shù)控系統(tǒng)制造商,越來越多的公司和外國公司,如德國西門子、日本發(fā)那科公司;國內(nèi)埃佛勒斯峰公司如中國、北京航空公司,華中數(shù)控系統(tǒng)的數(shù)控CNC高檔公司和沈陽國家工程研究中心。選擇數(shù)控系統(tǒng)中主要采用基于數(shù)控改造后成就各類精密機床、電機功率和用戶的要求來確定的。
第四,數(shù)控改造的主要步驟
1.測定的康復程序,
(1)機電維修改造相結合。一般來說,需要轉(zhuǎn)換的電氣設備,需要機械維修。點檢定修要求、范圍和內(nèi)容,以確定其電氣改造機械結構需要轉(zhuǎn)換要求和內(nèi)容;但也決定轉(zhuǎn)化的電氣和機械維修、改造交錯的時間之間的要求。完整的力學性能是電氣改造的成功。
(2)問題后更容易第一,第一批的整體。確定改造步伐,整個電氣部分改造應分為幾個子系統(tǒng)的基本形狀,不同系統(tǒng)完成后被連接到整個系統(tǒng)的工作。在每個子系統(tǒng)中,我們應該做的第一件事越少、工作量較大的技術工作,然后做一個技術要求高,做工精細,能集中人們的注意力到關鍵區(qū)。
(3)選拔制度的條件下使用。改造為對象的確定其環(huán)境和條件的選擇,電氣系統(tǒng)的保護、抗干擾、自扇冷和空氣過濾性能可提供正確的基礎。電力系統(tǒng)的選擇必須考慮成熟的產(chǎn)品,他們的表現(xiàn)應該是合理和實用的,有備件提供維護支持,具有多年來適應當前和未來的發(fā)展要求。
(4)實施人員的職責在重建。
(5)的轉(zhuǎn)換范圍的確定及周期。
2.改造的技術準備
(1)機械部件準備好了。符合機械電氣設備進行維修改造應提前完成。同時,被拆除,取而代之的加工應安排計劃的一部分,須妥善界面與整個轉(zhuǎn)型。
(2)在新系統(tǒng)電氣信息消化。
(3)轉(zhuǎn)換的舊體制的界面設計。根據(jù)每個人的不同范圍設備改造需要預先設計好的界面,部分轉(zhuǎn)換,如果整個轉(zhuǎn)型應該設計轉(zhuǎn)換為機械和電氣接口、操作面板控制和配置,互聯(lián)網(wǎng)的部分接觸,參數(shù)測量、保養(yǎng)等。要求操作和維修簡單、合理、隊列、流暢,初級和中級連接點電氣干擾少的力量,用一個合適的最小保證金等等。當?shù)氐霓D(zhuǎn)型,而且要考慮系統(tǒng)的性能匹配舊與新、電壓極性及大小的變化,安裝位置、信號轉(zhuǎn)換,等等,如果必要的話,需要創(chuàng)建自己的接口。
(4)操作和編程人員技術培訓。①培訓應包括新的控制面板配置、作用和意義的指示范圍;②新系統(tǒng)的特點,使用,和舊制度的區(qū)別;③;④保養(yǎng)要求編程標準和自動編程和更多。理解、把握重點操作規(guī)程,程序指令。
(5)的調(diào)試步驟和可接受標準的決心。調(diào)試應該由項目領導人進行的人。調(diào)試步驟可以由簡單到復雜,由小到大,從外到內(nèi),你也可以在第一個地方情況,整個系統(tǒng)在第一個子系統(tǒng)。驗收標準的發(fā)展必須面對現(xiàn)實,過高或過低標準將有負面影響,對轉(zhuǎn)變。
3.摘要改革
(1)整體維護機器。長期使用原機,你需要進行綜合維修。其次,對機床的反應來改變之前,空間的幾何精度測量精度,為記錄。用這種方法對參考引導變革的作用,但也轉(zhuǎn)型的過程中,最后進行比較分析。
(2)保留電動調(diào)整的一些最好的。如果電力系統(tǒng)的一部分轉(zhuǎn)化,反過來,應保留部件的維護和優(yōu)化調(diào)整,如高功率的一部分,電氣維修備件更換、干燥變壓器絕緣、污染、清潔、通風降溫設備清洗、伺服驅(qū)動優(yōu)化調(diào)整、更新老化的電線電纜、連接器和其他緊固。只有電氣部分預定的優(yōu)秀調(diào)整和優(yōu)化,以確保改造機床故障率較低。
(3)原系統(tǒng)被拆除。取消了原系統(tǒng)必須小心地控制原圖紙以讓馬克在圖紙,防止遺漏或被拆除。拆除過程中會發(fā)現(xiàn)一些新的制度設計在空白,這是及時補充和修正。移除系統(tǒng)應妥善維護以防不成功的重建恢復使用。有一定的價值,并可用于備件。
(4)合理安排的位置和接線的新系統(tǒng)。連接必須有清楚的分工,有一個人復習檢查,以確保連接工藝規(guī)范,直徑相配,正確、可靠和美麗。
(5)調(diào)試。調(diào)試必須建立程序和要求。第一個試驗調(diào)試安全保護系統(tǒng)靈敏度、個人和設備,防止事故發(fā)生。調(diào)試網(wǎng)站必須干凈;延長運動協(xié)調(diào)單位的中心,整個行程;能夠負載試驗、第一次在負載后,可以模擬空載實驗,第一次真正的行動后,首先模擬;手動手動和自動化水平。
4.接納和post-work
(1)的力學性能的機床驗收。機床應滿足要求的力學性能、幾何精度應規(guī)定的范圍內(nèi)。
(2)電氣控制功能和控制精度和接受。各種功能的電氣控制行為必須符合正常、靈敏、可靠。控制精度應用系統(tǒng)自身的功能(如一步尺寸等)和標準測量儀器(如激光干涉儀、坐標測量機等),達到控制檢查范圍內(nèi)。也應該被修改前的功能和精度機比較,獲得可量化指標的差異。
(3)測試片切削和接受?？蓞㈤営嘘P國內(nèi)、國際標準為數(shù)控切削標本,在一個合格的經(jīng)營者,程序員和審判,在切割。標本切割機工具可以接受剛度、切削力、噪聲、運動軌跡,相關的動作,一般都是不適合使用一種產(chǎn)品的樣品的部分。
(4)、圖紙、信息和接受。機改造完畢后,要及時進行圖紙、數(shù)據(jù)、轉(zhuǎn)換文件總結、整理、轉(zhuǎn)入文件。這樣的未來、穩(wěn)定運行設備是非常重要的。
(5)總結和改進。
五、數(shù)值實例的重建
1.銑床西門子810米X53轉(zhuǎn)型
1998年,公司于200000年投資元,與德國西門子810米數(shù)控系統(tǒng)、611交流伺服驅(qū)動系統(tǒng)在公司的X53模型的銑床,X,Y,Z三軸數(shù)控改造。保留了原有的主軸系統(tǒng)和冷卻系統(tǒng)。入力軸轉(zhuǎn)型滾珠螺桿用于機械齒輪傳動機制。轉(zhuǎn)化的工作包括機械設計、電氣設計、PLC程序準備和調(diào)試、機床維修、設備安裝和調(diào)試工作。改造后、銑削、加工、有效旅行X,Y,Z軸分別為270毫米、880毫米、280毫米,最大速度X,Y,Z軸分別5 000毫米/分鐘,1 500毫米/分鐘,800毫米/分鐘;點移動速度X,Y,Z軸分別是000毫米(3分鐘,000毫米/分鐘,500毫米/分鐘;加工精度±0.001毫米。機床坐標聯(lián)動,要完成各種復雜的曲線、曲面的加工。
2.GSK980T和步進驅(qū)動系統(tǒng)的轉(zhuǎn)型C6140車床
1999年,公司于800萬年投資元,廣州數(shù)控設備工廠生產(chǎn)GSK980T數(shù)控系統(tǒng),DY3步進驅(qū)動單元混合在公司的長C6140 X、Z兩車床改造。保留了原有的主軸系統(tǒng)和冷卻系統(tǒng)。two-axis轉(zhuǎn)型滾珠絲杠的機器的使用,和同步傳輸。轉(zhuǎn)化的工作包括機械設計、電氣設計、機器檢修和機器的安裝和調(diào)試。改造后的車床、加工和有效X、Z軸分別中風,390毫米、1400毫米,最大速度X、Z軸分別1 200毫米/分鐘,3 000毫米/分鐘;慢跑400毫米/分鐘;速度點快速的移動,X、Z軸分別1 200毫米/分鐘,3 000毫米/分鐘;機器最小移動單位0.001毫米。
6、數(shù)值變換的問題和建議
1.轉(zhuǎn)化問題的數(shù)控
通過幾個數(shù)控機床改造和找工作,也存在很多問題,主要體現(xiàn)在:(一)有關部門、開發(fā)商不確定的功能、組織混亂,嚴重影響了發(fā)展轉(zhuǎn)型;(2)開發(fā)工作流程和計劃大多數(shù)發(fā)達的拇指規(guī)則,更少的合理的;(3)相關人員的培訓不到位,導致機床技術官員將不會進行修改后,程序設計中,機器操作熟練的操作人員等。
2.該數(shù)控改造
(1)負責員工的責任轉(zhuǎn)變清晰的懲罰和獎勵,充分調(diào)動員工的積極性,培養(yǎng)了一批高質(zhì)量的應用程序和維修人員的培訓人員,選擇去學習先進的技術;
(2)為重點,為維護數(shù)控系統(tǒng)用戶的技術培訓,建立數(shù)控技術在國內(nèi)外資源的圖書館。建立技術數(shù)據(jù)文件,做的工作,備件。