CNC Machining and numerical control system

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Does CNC Machining have He Hao to be in? Numerical control is advanced the fundamental technology of production technology. CNC Machining shows very big advantage in modern production. To modern manufacturing industry, numerical control machine tool suits those appearance very much the part with complex, nicety and small batch. And common general accuracy machine tool cannot satisfy this requirement at all. With respect to Lian Fang form machine tool and modular machine tool also cannot solve high accuracy and small lot this is contradictory. Because this CNC Machining suits aviation, spaceflight, electric power, traffic and electron very much,wait for the spare parts processing technique of manufacturing industry. The high accuracy that a when spare parts treatment is faced with main problem is a product, diversity and batch contradict smally. This needs to numerical control from the machine tool with respect to the requirement flexible. Because system of CNC numerical control uses software control, had very big flexible. The good point that its stress contemporary numerical control machine tool is to be able to undertake high accuracy treatment and diversification are machined, can replace other treatment methods completely. Because numerical control machine tool is,machine automatically according to booked order, treatment process does not need artificial interpose, treatment precision still can undertake through software corrective reach compensation, because this can raise the treatment precision of the spare parts, stabilize the quality of the product. Special more such to the spare parts of much breed, little batch. Use numerical control machine tool to be able to improve productivity additionally, can improve manufacturing efficiency commonly 2 ～ 3 times, to the treatment precision of certain and complex part, productivity can rise 10 severalfold, taller even. Machine tool of a few numerical control, have multitask to trade knife unit foreword, automatically, because this can realize one machine multi-purpose, not only improved manufacturing efficiency, also can save workshop area. System of more numerical control of FANUC 0 series is being used in our country market now is the numerical control system of a kind of high accuracy, complete function. It is had better flexible, suit the treatment of mechanical spare parts very much. What is the main index that judges actor of numerical control system, of low quality? Reliability is the most fundamental in these index is dependability. The index of dependability uses average time to failure commonly (MTBF unit is hour) . Some companies use fault rate (Failure Rate unit is second / ) of lunar · stage. The time to failure of numerical control machine tool is 500h commonly, this is more than it with respect to the time to failure of system of demand numerical control. The time to failure of system of domestic numerical control can be achieved now 5, 000 ～ 10, 000 H, taller even, abroad is 10, 000h above. The fault rate of the FS-O system of FANUC company is 0.

008 / lunar · stage. Be equivalent to time to failure for 90, 000h. The injunction that the function wants to view numerical control system above all is worth limits to whether satisfy the need of the machine tool. These dictate value scope includes: The dimension of the increment of increment of the smallest input, the smallest instruction, biggest process designing, biggest move quickly limits of rate of speed, feed. The resolution of numerical control machine tool and the speed that move quickly and the index that machine speed limits indicate the main demand of the machine tool, also be the main index of numerical control system. The class of these index and numerical control system is concerned. Resolution shows interpolation ability of the system, and when considering whole instruction range, it is returned and the index of servo device is concerned. Whether can the function basically satisfy the requirement of the machine tool. System of ordinary numerical control has two kinds of functions, basic function and choice function. Former it is the function that numerical control system has, latter is the function that when the user chooses, just provides, every increase an option to be about to raise fair price. Accordingly, to improve the economy of numerical control machine tool, the function to numerical control system must according to need, choose carefully. The category of the function of numerical control system and numerical control system is concerned, for example, the function of numerical control lathe and CNC Milling is different, accordingly, should choose different systematic function to the machine tool of distinct category. When choosing a function must decide according to the utility of numerical control machine tool, the systematic function of different class is different also. The idea that thinks the function has been jumped over more more one-sidedly is incorrect. In the job shops of our country, use of general numerical control machine tool specializations quite. Accordingly, needless pick the system that has a lot of functions, will raise bought price in that way. Economy. What is the basic course of numerical control system? Average numerical control system has 3 kinds of basic interpolation functions, locate namely (G00) , linear interpolation (interpolation of G01) , circular arc (G02, g03) . The program these 3 kinds of interpolation calls main program (request an audience " the function of numerical control system " ) . Ask the specification of program adduce example that pair of G00, GO1, G02, G03 sows filling function 3 kinds. Exemple (interpolation of 1) fixed position: Its program is G00 X25.

0Y 10.

0; If its method pursues 1. Exemple of give typical examples of 2 G01 of graph of give typical examples of 3 G02 of graph of give typical examples of graph 1 G00 (2) linear interpolation: Its program is (G91)G01 X200.

0Y100.

0F200.

0; If its method pursues 2. Exemple (interpolation of 3) circular arc: Its program is (the 180 ° of circular arc ＜ of ① ) G02 X60.

0Y20.

0R50.

0F300.

0; If its method pursues 3. Exemple (interpolation of 4) circular arc: Its program is (the 180 ° of circular arc ＞ of ② ) G02 X60.

0Y20.

0R-50.

0F300.

0; If its method pursues 3. What is " machine tool at 0 o'clock " ? By the mechanical origin that machine tool manufacturer sets. What is " reference point " ? Alleged " reference point " be secure a place along a of reference axis, it can be reference with origin of machine tool coordinate fiducial. What is " return reference point " ? Fixed position is called to the process of reference point return reference point. The process that uses an operation to return reference point by the hand is called " the hand moves go back reference point " . And return the process 0 o'clock automatically to call according to G code of the regulation " return reference point automatically " . Graph 4 hands move go back reference point to pursue the process of reference point of 5 voluntary withdrawal pursues 4 use the process that returns reference point for ordinary hand. Around the reference point of reference axis a decelerate nods set. Return reference point automatically to be dictated by G28, in the block of G28, stocked the value of intermediate dot coordinate of instruction axis. The instruction of G28 block operates as follows: ① chooses location among the axial tend the instruction (A dot nods) to B. ② locates to reference point from the dot intermediate (B dot nods) to R. If ③ is not the machine tool chains condition, return reference point lamp to shine. When locating with intermediate dot to reference point, each axis moves with rapid rate. Should dictate general in order to changes a knife automatically (ATC) . Accordingly, the need when implementing this directive cancels compensation of cutting tool radius and compensation of cutting tool length. The reference that returning reference point is machine tool of formulate numerical control and connection of numerical control system is fiducial. Because this is very important. What is the meaning that G29 dictates? G29 is the instruction that returns automatically from reference point. It shows designation axis chooses the course that locates to designation position among the course. Return the 2nd reference point in G28 or G30(normally) later use. If G29 operation pursues 5 medium (4) and (5) ; (The axis that 4) is appointed, the intermediate point that defines to G28 or G30 locates (R dot nods) to B; (5) locates to the feature that is assigned from the dot intermediate (B dot nods) to C; With rapid rate to among, designation point is floating. CNC Milling