數控工具機在飛機零件加工上的應用

The main processing objects of CNC machine tools are aircraft parts with complex profiles, which solves the key equipment that is difficult to solve by ordinary processing methods. The biggest feature of CNC machining is the use of punched tape (或膠帶) 控制工具機進行自動加工. Because airplanes, rockets and engine parts have different characteristics: Aircraft and rockets have large components, large size and complex shapes; Engine zero, small component size and high precision. 所以, the CNC machine tools selected by the aircraft and rocket manufacturing departments and the engine manufacturing departments are different. Large-scale CNC milling machines with continuous control are mainly used in aircraft and rocket manufacturing. In engine manufacturing, both continuous-control CNC machine tools and point-control CNC machine tools (such as CNC drilling machines, CNC鏜床, 加工中心, ETC。) 被使用.

製程濃度
CNC machine tools generally have tool holders and tool magazines that can automatically change tools. The tool change process is automatically controlled by the program, so the process is relatively concentrated. Process concentration brings huge economic benefits:
⑴ Reduce the floor space of the machine tool and save the workshop.
⑵ Reduce or eliminate intermediate links (如半成品的中間檢驗, temporary storage and handling, ETC。), which saves time and labor.
自動化
在CNC機床上加工時, 不需要手動工具控制, 且自動化程度高. 好處是顯而易見的.
⑴ 降低對操作人員的技術要求:
普通工具機高級工不可能在短時間內培養出來. 然而, 不需要程式設計的CNC員工的訓練時間很短 (例如, 一名CNC車床工人只需要一周, 他會編寫簡單的處理程序). 另外, 數控工人在CNC機床上加工的零件比一般工人在傳統機床上加工的零件精度更高, 並且需要更少的時間.
⑵ Reduce the labor intensity of workers: In the machining process, most of the time CNC workers are excluded from the machining process, which is very labor-saving.

⑶ Stable quality of processed parts:
The processing automation of CNC machine tools eliminates the fatigue and carelessness of workers on ordinary machine tools and improves the consistency of products.
⑷ High processing efficiency:
The automatic tool change of CNC machine tools makes the processing process compact and improves labor productivity.

High flexibility of machined parts
Although the traditional general-purpose machine tool is flexible, its efficiency is low; Although traditional special planes are highly efficient, they have poor adaptability to parts, 高剛性, and poor flexibility, making it difficult to adapt to frequent product modifications brought about by fierce competition in the market economy. As long as the program is changed, new parts can be processed on the CNC machine tool, and it can be automated, with good flexibility and high efficiency. 所以, the CNC machine tool can adapt to market competition.

Strong ability to process parts
The machine tool can accurately process various contours, and some contours cannot be machined on ordinary machine tools. CNC machine tools are especially suitable for the following occasions:
1. Parts that are not allowed to be scrapped.
2. 新產品開發.
3. Processing of urgently needed parts.

Machining principles of precision parts
⑴ The processing of the previous process cannot affect the positioning and clamping of the next process.
⑵ Inside first, then outside, 那是, the inner cavity (內孔) is processed first, and then the shape is processed.
⑶應連續執行具有相同安裝或使用相同工具的處理過程，以減少由重新定位或工具更改引起的錯誤.
⑷在同一安裝中, 對工件的剛性幾乎沒有影響的過程應首先進行.

精確零件的處理路線
CNC車床的飼料處理路線是指轉彎工具從工具設置點移動的路徑 (或機床的固定來源) 直到它返回到這一點並結束處理程序. 包括切割路徑和非切割閒置路徑，例如切入和切出工具. 完成的進料路徑基本上是沿零件輪廓序列進行的. 所以, 確定進料路線的重點是確定粗加工和閒置的進料路線. 在CNC車床處理中, 處理路線的確定通常遵循以下原則.
①應保證已加工工件的準確性和表面粗糙度.
②使處理路線最短, 減少閒置旅行時間, 並提高處理效率.
③嘗試簡化數值計算的工作量並簡化處理過程.
④對於一些可重複使用的程序, 應該使用子例程.
使加工程序具有最短的供稿路線，不僅可以節省整個加工過程的執行時間, 但還減少了機床飼料機構的滑動部分的不必要的工具消耗和磨損. 最短進料路徑的類型和實現方法如下.
⑴最短的切割飼料路線. 最短的切割飼料路徑可以有效提高生產效率並降低工具損失. 安排最短的切割飼料路線時, 還必須確保工件的剛度和處理技術的要求.
⑵最短的NC空旅行路線.
①熟練使用起點. 使用矩形環方法進行粗糙轉彎的一般情況的一個示例. 工具設置A的設置A是考慮到在完成和其他處理過程中需要方便的工具更換的需求, so it is set at a position far away from the blank, 同時, the starting point and the tool setting point are overlapped
② Ingeniously set the tool change point. In order to consider the convenience and safety of tool change, sometimes the tool change point is also set at a position far away from the blank. Then, when the second tool is changed, the idle stroke path during fine turning must be longer; If the tool change point of the second tool is also set at the mother point position in the middle, the idle stroke distance can be shortened.

精密CNC加工飛機零件

Process of machining aluminum engine cavity

cnc milling molybdenum aircraft parts

Processing Technology of Ship's Automatic Miniature Titanium Parts

③ Reasonably arrange the "return to zero" route. 為了簡化計算過程並在手動編譯複雜輪廓的處理程序時促進驗證, 每次切割後，程序員有時會設置工具的終點. 通過執行 "return to zero" 操作說明, 所有人都返回工具設置點的位置, 然後執行後續程序. 這將增加進料路徑的距離並降低生產效率. 所以, 合理地安排 "return to zero" route, 上一個切割結束與下一個切割的開始之間的距離應盡可能短. 或零以滿足最短的進料路徑要求. 另外, 選擇命令返回工具設置點時, 在不干預的前提下, use the x and z axis bidirectional “zero return” command as much as possible. The function "return to zero" route is the shortest.
⑶ Step cutting feed route of large margin blank. Lists two cutting feed routes for blanks with too much margin. It is a wrong step cutting route, cut in the order of 1→5, and the margin left for each cutting is equal. It is the correct step cutting feed route. Because under the same amount of knife back.
⑷ Continuous cutting feed route for finishing part contour. The finishing of the contour of the part can be arranged with one or several finishing processes. The final contour is completed by the last continuous machining. 此時, the advance and retreat position of the tool should be selected appropriately, and try not to arrange cutting and cutting out or tool change and pause in a continuous contour. So as not to destroy the balance of the process system due to sudden changes in cutting force. Causes scratches, shape changes or retained tool marks on the contour of the part.
⑸ Special feed route. 在CNC車削加工中, 一般來說. The longitudinal feed of the tool is fed along the negative direction of the coordinate, but sometimes it is unreasonable to arrange the feed route in the normal negative direction. It may even damage the workpiece.

CNC machining has the following advantages:
① The number of tooling is greatly reduced, and complex tooling is not required for processing parts with complex shapes. If you want to change the shape and size of the part, you only need to modify the part processing program, which is suitable for new product development and modification.
② The processing quality is stable, the processing accuracy is high, and the repeat accuracy is high, which is suitable for the processing requirements of aircraft parts.
③ Higher production efficiency in the case of multiple varieties and small batch production. Can reduce production preparation, machine tool adjustment and process inspection time, and reduce the cutting time due to the use of the best cutting amount.
④ It can process complex surfaces that are difficult to process by conventional methods, and even process some unobservable processing parts. The disadvantage of CNC machining is that the cost of machine tool equipment is expensive and requires a high level of maintenance personnel.