Views:2890 Author:Site Editor Publish Time: 2019-04-12 Origin:Site
Currently, CNC machining is used more and more common in our daily life. People prefer choosing CNC machining to manufacture products. But, do you know when did CNC machining start? How is CNC machining designed? How much time does CNC machining take? Today, this short essay will show you the answers to these three questioned asked before.
1. The Starting Time of CNC Machining
2. Design of CNC Machining
3. Time of CNC Machining take
There are two version early. One is NC(Numerical Control), which represents the old version of the original CNC technology. The other one is CNC(Computerized Numerical Control), which is the new one. NC may be CNC, but CNC is by no means an old CNC technology. The early CNC system was composed of hardware circuits called Hardware NC. After the 1970s, hardware circuit components were gradually replaced by dedicated computers and called computer numerical control systems. Generally, special computers were used and interface circuits were used. It can realize the control of the movement of multiple numerical control devices. Therefore, the current CNC is generally CNC (computerized numerical control), and the concept of NC is rarely used again.
In 1952, MIT developed a three-axis NC milling machine. In the mid 1950s, this CNC milling machine was used to process aircraft parts. In the 1960s, CNC system and program design became more and more mature and perfect. CNC machine tools have been used in various industrial sectors, but the aerospace industry has been the largest user of CNC machine tools. Some large aviation factories are equipped with hundreds of CNC machine tools, mainly cutting machines.
CNC machining parts include aircraft and rocket integral siding, girders, skins, bulkheads, propellers, and aircraft engine casings, shafts, discs, blade mold cavities, and special cavity surfaces for liquid rocket engine combustion chambers. . The initial development of CNC machine tools is based on continuous trajectory CNC machine tools, continuous trajectory control. Continuous trajectory control, also known as contour control, requires the tool to move relative to the part in a defined trajectory. In the future, we will vigorously develop point-controlled CNC machine tools. Point control means that the tool moves from one point to another, as long as it finally reaches the target accurately regardless of the movement route. The CNC system sends operational or termination information to the servos and other functional components to control various movements of the machine according to program instructions. When the part's machining program ends, the machine will automatically stop.
For any CNC machine, if there is no program command input in its CNC system, the CNC machine will not work. The controlled actions of the machine tool generally include the starting and stopping of the machine tool; the start and stop of the spindle, the change of the direction of rotation and the speed; the direction, speed and mode of the feed motion; the selection of the tool, the compensation of the length and radius; the replacement of the tool, opening and closing of coolant, etc.
Compare the parts you are cutting with similar operations. If the new part has more complex cutting, it can be assumed that it will take longer than the original part. You can also view prints and final sizes to estimate cycle time. If the roughing volume is large, it may take longer, because roughing is usually about half of the finishing cutting. View the amount of tool changes in the program. This will affect the cycle time. If there are 10 or more tool changes, the cycle will be longer than using only one tool. It takes time for the machine to put one tool back into the turret and grab another. Use the feed rate and the number of passes in the program to calculate the time it will take. If the roughing channel runs at 2 inches per minute and the size of the part is 6 inches, it will take 12 minutes. Estimate other passes, including completion of cuts. Add this value and estimate each tool change for about 30 seconds to estimate the total time.
From this essay we can know that it has been a long time since the first time we use CNC machining, it has improved a lot. We know that CNC machining is designed Intricate and it requires special ability. What’s more, the working time of CNC machining is not fixed, it will change with different conditions.