【Pause command】 Precision Machined Parts China | Get Custom Prototypes in Days.
G04X(U)_/P_ refers to the tool pause time (feed stop, spindle does not stop), the value after address P or X is the pause time. The value behind X is to have a decimal point, otherwise it is calculated as one-thousandth of this value in seconds (s). The value after P cannot have a decimal point (integer representation) in milliseconds (ms). However, in some hole machining instructions (such as G82, G88, and G89), in order to ensure the bottom of the hole roughness, when the tool processing to the bottom of the hole requires a pause, this time can only be used address P, if used The address X indicates that the control system considers X to be an X-axis coordinate value for execution. Precision Machined Parts China | Get Custom Prototypes in Days.
[M00, M01, M02, and M03 differences and links]
M00 is an unconditional pause instruction for the program. The program execution stops here until the spindle stops. To restart the program, you must first return to the JOG state, press the CW (spindle forward rotation) to start the spindle, then return to the AUTO state, press the START button to start the program.
M01 is a program selective suspend instruction. Before executing the program, the OPSTOP button on the control panel must be opened to execute. The effect after execution is the same as that of M00. The restart procedure is the same as above. M00 and M01 are often used for inspection or chip evacuation of mid-process workpiece sizes. M02 is the main program end instruction. When this command is executed, the feed stops, the spindle stops, and the coolant turns off. However, the program cursor stops at the end of the program. M30 is the main program end instruction. The difference between the function and M02 is that the cursor returns to the program header position, regardless of whether there are other program segments after M30. Precision Machined Parts China | Get Custom Prototypes in Days.
[Address D, H have the same meaning]
The tool compensation parameters D and H have the same function and can be interchanged arbitrarily. They all represent the address names of the compensation registers in the numerical control system. However, the specific compensation value is determined by the offset number address following them. However, in the machining center, in order to prevent errors, it is generally prescribed that H is the tool length compensation address, the compensation number is from 1 to 20, D is the tool radius compensation address, and the compensation number starts from 21 (20 tool magazines).
Mirror processing instructions M21, M22, M23. When only the X-axis or Y-axis is mirrored, the cutting sequence (climb and up-cut), the tool compensation direction, and the circular interpolation direction are opposite to the actual program. When the X-axis and Y-axis are mirrored at the same time, the cutting sequence, tool compensation direction, and circular interpolation direction are all unchanged. Precision Machined Parts China | Get Custom Prototypes in Days.
Note: M23 must be canceled after using mirroring instructions to avoid affecting the following programs. In G90 mode, use the mirror or cancel instruction to return to the origin of the workpiece coordinate system. Otherwise, the CNC system cannot calculate the motion trajectory behind it, and it will cause chaos. At this time, manual origin return operation must be implemented. Spindle steering does not change with mirroring instructions.
[Circular interpolation instruction]
G02 clockwise interpolation, G03 counterclockwise interpolation, in the XY plane, the format is as follows: G02/G03X_Y_I_K_F_ or G02/G or 03X_Y_R_F_, where X, Y arc end coordinates, I, J arc starting point To the center of the X, Y axis incremental value, R is the radius of the arc, F is the amount of feed.
Pay attention to circular cutting, q ≤ 180 °, R is a positive value; q> 180 °, R is a negative value; I, K can also be used to specify R, when both are specified, R command priority, I , K is invalid; R can not be done with full circle cutting, full circle cutting can only be programmed with I, J, K, because after the same point, there are numerous circles with the same radius. Precision Machined Parts China | Get Custom Prototypes in Days.
When I and K are zero, they can be omitted; regardless of G90 or G91 mode, I, J, and K are programmed according to relative coordinates; when circular interpolation is performed, tool compensation instructions G41/G42 cannot be used.
[The advantages and disadvantages between G92 and G54-G59]
G54～G59 are the coordinate system set before machining, and G92 is the coordinate system set in the program. If G54～G59 are used, it is not necessary to use G92. Otherwise, G54～G59 will be replaced and should be avoided.
Note: (1) Once G92 is used to set the coordinate system, the use of G54 to G59 will have no effect unless the power is turned off to restart the system, or G92 is then used to set the desired new workpiece coordinate system. (2) After the G92 program is used, if the machine tool does not return to the G92 set point, the program will be started again. The current position of the machine tool will become the new workpiece coordinate origin, which is prone to accidents. Therefore, it must be used with caution. Precision Machined Parts China | Get Custom Prototypes in Days.
[programming for knife program]
In machining centers, tool change is inevitable. However, when the machine is shipped from the factory, it has a fixed tool change point. If it is not in the tool change position, it will not be able to change the tool. Before the tool change, the tool compensation and cycle must be cancelled, the spindle is stopped, and the coolant is turned off. There are many conditions. If these conditions are to be guaranteed before each manual tool change, it is not only error-prone but also inefficient. Therefore, we can program a tool change program to be saved, and then use M98 to invoke the tool change operation.
Take the PMC-10V20 machining center as an example, the procedure is as follows:
G80G40G49;(cancelling cycle, tool offset)
M05; (spindle stop)
M09; (Coolant off)
G91G30Z0; (The Z axis returns to the second point of origin, which is the tool change point)
M06; (tool change)
M99; (end of subroutine)
When a tool change is needed, simply enter “T5M98P2002” in the MDI status and replace the required tool T5, thus avoiding many unnecessary mistakes. According to the characteristics of your own machine tool, you can program a corresponding knife change program. Precision Machined Parts China | Get Custom Prototypes in Days.
[In the same program segment, the same instruction (the same address character) or the same group of instructions, after the function]
For example, the tool change program, T2M06T3; replaces T3 instead of T2; G01G00X50.0Y30.0F200; executes G00 (although there is an F value, but G01 is not executed). Not the same set of instruction codes, the same order of execution in the same program segment. G90G54G00X0Y0Z100.0;G00G90G54X0Y0Z100.0; The above items are all running on the PMC-10V20 (FANUCSYSTEM) machining center. In practical applications, the usage and programming rules of various instructions should be thoroughly understood. Precision Machined Parts China | Get Custom Prototypes in Days.
Block sequence number, represented by the address N. The general numerical control device itself has limited memory space. To save memory space, the sequence number of the program segment is omitted. N only indicates the block number, which can be used to easily find the editing program and does not have any effect on the machining process. The sequence number can be incremented or decremented, and there is no requirement for numerical continuity. However, it cannot be omitted when using some loop instructions, jump instructions, calling subroutines and mirroring instructions. Precision Machined Parts China | Get Custom Prototypes in Days.