October 2020 – CNC Machining & Turning, Milling, Metal parts

What is RC Car?

RC car (RC = remote control) is a miniaturized version of all kinds of real racing cars. It has the same mechanical principle as the real car, similar structure and handling characteristics, and the amazing speed that makes super sports cars feel inferior! Take one eighth of the level road remote-controlled cars, for example, which can accelerate from standstill to 100km / h in 1.6 seconds and reach a top speed of 160km / h. This performance is equal to that of the world’s most technologically advanced formula one racing cars, and makes all super sports cars blush. The reason why remote control model is considered as “hobby” rather than “toys” is that the remote control model requires players to have certain knowledge and technology, which is fundamentally different from toys that can be bought and played. Players can not only have fun in the operation of the model, but also constantly learn new knowledge in the model, exercise thinking ability and practical ability. Therefore, remote control model is definitely a hobby beneficial to the body and mind. Although driving a remote control model car can not control the steering wheel in the car, it can only control the car through the wireless remote control, but in fact, the pleasure obtained through the eyes is no less than that In the real car, because you can enjoy the lightning speed and strong ability to cross the corner. If speed is not your pursuit, you can choose a remote control vehicle with high fidelity or various interesting functions, such as watching several unreal container trucks walking, driving a jumbo to conquer rugged roads, and driving an AE86 drift remote control model car to deliver bean curd by Tuohai, who plays the first character D, is also a fun remote control enjoyment.

Remote control model vehicles can be divided into two categories according to the power source. The first category is “EPRC car” driven by battery / electric motor, and the second is “GP RC car” with internal combustion engine as power output. According to the proportion, there are 1 / 28, 1 / 18, 1 / 10, 1 / 8 and 1 / 5. For example, 1 / 10 is about one tenth of the size of the real car. At present, there are 1 / 10 electric saloon cars, 1 / 10 oil powered saloon cars, 1 / 8 large foot trucks and 1 / 8 oil powered off-road vehicles. In the future, we will make an in-depth introduction to each type of vehicles. You can choose your favorite remote control model car according to the characteristics of each vehicle type, so that we can realize the model dream together.

The product of high technology

Remote control model car can be said to be a product of high technology, widely used in many advanced materials and technologies, such as carbon fiber, titanium alloy, aviation aluminum, in the remote control vehicle are very common parts materials. Moreover, the latest electrical / electronic technology and digital technology have been applied to remote control vehicles for the first time.

CHENGCHUANG are China machining parts workshop for Radio Control R/C Planes, RC Airplanes, RC Helis and Helicopters, RC Cars, RC Trucks, RC Truggys, RC Boats, RC Radios, RC Engines, parts, hop-ups, and accessories, We can produce machined parts according to your requirements. high quality, low price, low cost OEM CNC Machining service.

RC remote control vehicle frame

RC is the abbreviation of radio control. It is not a very popular sport either at home or abroad. Why do you say that? RC is really a sport that requires a lot of time and money. Therefore, those who have money foundation do not necessarily have the time, and those who have time do not necessarily have the money to play RC remote control model car entry – Adult remote control toys.

A complete set of RC includes the following parts (this article only takes the remote control vehicle as an example) firstly, the frame, the remote control system, the power and steering system, and finally some auxiliary materials such as tools and oil products.

The foundation of RC is the frame. Different types of RC models will have different types of frames. The figure above shows a flat road sports car, referred to as level running. Other categories include off-road vehicles, short-distance trucks, big foot trucks, climbing cars, F1, drift cars, etc. due to the different transmission structures, they can also be divided into belt drive and shaft drive. The above figure shows belt driven motor car. The frame can also be divided according to the proportion: 1:16 1:14 1:12 1:10 1:8, 1:5 and so on. Generally speaking, those below 1:20 are collectively referred to as mosquito vehicles, and the most popular ones are 1:10 and 1:8.

In fact, the biggest difference between RC and other remote-control toy cars is the frame. The RC frame can be adjusted from the height of the car to the inclination of the tire, the tightness of the transmission device, and the height of the shock absorbers. This is to adapt to different remote control methods and the needs of different venues. This is also one of the fun of RC. Even if the same frame is in the hands of different people, there will be different settings and different motion characteristics because of the manipulation.

Our factory specializes in RC frame by CNC machining, welcome to contact us for customized.

RC Driver Cup/Shaft

Drive shaft for RC car, 4WD car, Monster Racer XXL

Outdrive for Rc parts — Drive shaft for RC car, 4WD car, Monster Racer XXL

Our factory specializes in RC Driver Cup/Shaft by CNC machining.

Drive shaft description

Working conditions

The driving shaft is subjected to, torsion, shear, tension, compression, impact and other alternating stresses, which can also cause the torsional and bending vibration of the drive shaft and generate additional stress; the stress distribution is uneven; there is sliding friction between the drive shaft journal and the bearing.

performance requirement

The main failure modes of drive shaft are fatigue fracture and serious wear of journal. Therefore, the material should have high strength, certain impact toughness, enough bending and torsion fatigue strength and stiffness, and the journal surface should have high hardness and wear resistance.

Drive shaft material

Forged steel drive shaft: high quality medium carbon steel and medium carbon alloy steel, such as 40, 45, 35Mn2, 40Cr, 45Cr, 35CrMo steel, etc;

Material selection

This kind of material is medium carbon alloy steel, which can be improved by quenching and tempering (or normalizing) heat treatment. In recent years, a new kind of steel, namely alloy quenched and tempered steel, has been widely used in high-power engines. The grain size is refined by adding alloy elements such as Si, Cu and Ti, strengthening the steel matrix and improving the strength of the steel.

Computer gong machining – crankshaft

In internal combustion engine, the function of crankshaft is to convert reciprocating motion of piston into rotary motion. This means severe acceleration and deceleration, accompanied by high bending deformation, high torque and vibration impact, results in very high and variable stresses.

Such extreme stress requires careful design and calculation, selection of suitable materials and batch production process. These stresses are mainly located at the fillet radius between the bearing journal and the balance weight plate as well as on the oil hole, so it is necessary to pay special attention to the fine fabrication of these spaces.

In today’s market, automobile manufacturers are required to provide smaller engines while meeting higher power and speed requirements, which further increases the load and stress of the crankshaft. As a result, manufacturers are constantly looking for higher strength materials for these parts, usually including high alloy metals.

Ductile iron is the standard material for lower load engines (mainly gasoline engines), while high-power engines (including most diesel engines) use more expensive alloy steel forgings. The steels used for crankshafts are generally subjected to various heat treatments, such as quenching and tempering. In some special high-end use areas (including racing cars), crankshafts may be made directly from round steel.

At present, the requirement of large-scale precision machining for crankshaft is the most strict. Crankshaft manufacturing line has also become the largest consumer of cemented carbide in the whole process of automobile production.

A simple method of finishing both ends and Journal of crankshaft is turning on a traditional lathe or turning center. This clearly requires sufficient space from the handle to the finished journal appearance. The advantages of this approach include the ability to apply standardized machine tools, tool heads and blades to achieve high flexibility and low cost.

With the ability of turning and turning, a special machine tool can finish the Journal on the crankshaft rotation center. The blades used for rough and fine manufacturing can be installed on the same cutter head at the same time. High speed computer gongs can be used to make a special shape in one complete cutting stroke. Other benefits include repeated positioning accuracy, good finish appearance quality, smaller tolerance, longer tool head life, higher machine tool utilization due to reduced tool change times, and shorter finishing time. The disadvantage of turning and drawing fine production is that the cost of special machine tool and cutter head is high, and a large number of blades are needed. A more professional way of turning is to use multi tooth turning blades to achieve cost reduction efforts conducive to scrap iron control and not to use broaching action.

No matter what method is adopted, the overall goal of crankshaft finishing includes scrap iron control, prolonging tool head life, shortening finishing beat and improving product quality. Crankshafts are usually manufactured in large quantities on a production line consisting of several special machine tools. However, the one-piece refinement method can also be used in some special turnkey projects, such as racing engine crankshaft and marine diesel crankshaft.

External and internal milling represents another approach, especially the finishing of the connecting rod neck. If the balance weight has large allowance to be removed, the milling cutter head with cutter block with blade is an attractive choice. Sandvik has more than 40 years of experience with these uses. Oil hole drilling and milling are the most consumed technologies of cemented carbide in crankshaft manufacturing.

In the crankshaft oil hole, the hole depth is usually 20 times of the diameter, so it is very difficult to finish the task. The most widely used tools include gun drill and carbide twist drill lubricated by oil mist. High quality precision fabrication is also essential because of the possibility of major stresses around the borehole.

Stefan Knecht, global solutions manager of the crankshaft capability center in Dusseldorf, Germany, said: “although there are hundreds of cutting tool head manufacturers in the world, only six have the ability to supply cutting heads for crankshaft precision manufacturing, and even fewer companies really promote the technology development of the industry. Sandvik is one of the few

The center works with OEMs and machine tool manufacturers around the world, with projects in about 20 countries. Emerging markets are expanding in this area, especially in China, where the centre recently opened a new branch.

Crankshaft precision manufacturing is one of the most demanding industries in automobile production. The key requirements of all finishing methods are the same, including scrap iron control, prolonging tool head life, shortening finishing beat and improving product quality.

CNC machining – boring

1 tool rotation

Different from lathe processing, because of tool rotation in machining center, it is impossible to master the situation of tool tip in time to adjust the feed rate. It is impossible to change the machining diameter just by adjusting the NC button like the NC lathe. This has become a big obstacle to fully automated processing. Because the machining center does not have the function of automatic diameter adjustment (except for those with U-axis function), the boring cutter must be equipped with fine adjustment mechanism or automatic compensation function, especially in fine boring, sometimes it must be adjusted at micron level according to tolerance requirements.

When machining center boring, because the direction of chip outflow is constantly changing, it is much more difficult to cool the tool tip, workpiece and chip discharge than when machining with a lathe. Especially when the longitudinal machining center is used for rough boring of steel blind hole, this problem has not been completely solved.

2 chatter

Chatter is the most common and headache problem in boring. The main causes of chatter on machining center are as follows:

① Rigidity of tool system: including the rigidity of toolholder, boring bar, boring head and intermediate connecting part. CNC machining is a kind of cantilever machining, so the rigidity of tool system is very important, especially when machining small holes, deep holes and hard workpieces.

② Balance of tool system: relative to the rotating axis of the tool system, if there is an unbalanced mass of the tool itself, the chatter will occur due to the action of unbalanced centrifugal force during rotation. Especially in high speed machining, the dynamic balance of the tool has a great influence.

③ Clamping rigidity of workpiece itself or workpiece: for example, some small and thin parts cannot be fully fixed with reasonable fixture due to insufficient rigidity or workpiece shape.

④ Geometry of edge: different rake angle, escape angle, nose radius and chip breaking groove shape have different cutting resistance.

What we call boring in CNC machining center is to enlarge or refine the original hole on the workpiece. The feature of CNC machining is to correct the eccentricity of the lower hole, obtain the accurate position of the hole, and obtain high-precision roundness, cylindricity and surface finish. Therefore, boring as a high-precision machining method is often used in the final process. For example, the bearing holes of various machines and the processing of boxes and covers of various engines.

Compared with other machining, boring is a difficult process. It only needs to adjust one blade (or blade holder) to process micron sized holes such as H7 and H6. With the popularization of machining center, the boring process only needs programming and button operation. Because of this, it is necessary to have simpler, more convenient and more precise cutting tools to ensure the quality of products.

Computer gong – manual adjustment of spindle

Computer gongs processing in the center can complete milling, boring, drilling, expanding, reaming, tapping and other programs of a variety of processing, the process is highly concentrated. The machining center is equipped with a tool magazine and an automatic tool change device. CNC machining will load the required tools into the tool library before processing, and the tools can be changed automatically through program control. If the machining center is equipped with automatic exchange worktable, it can realize that one worktable can complete the clamping of workpieces at the same time of processing, thus greatly reducing the auxiliary time of processing and improving the processing efficiency.

The commissioning of vertical center should follow the following steps:

According to the requirements of the manual, oil the lubrication points of the vertical machining center, fill the hydraulic oil tank with the required hydraulic oil, and connect the air source.
Power on the vertical center, supply power to each component separately or after one power on test, the high-speed computer gongs process and then fully supply power. Observe whether the components have alarm, whether the manual operation parts are normal, whether the safety devices work, so that all links of the machine tool can operate and move.
After the initial operation of the vertical machining center, the geometric accuracy of the machine tool is roughly adjusted, and the relative position of the main moving parts and the host machine after disassembly and assembly is adjusted. The manipulator, tool magazine, exchange table, position alignment, etc. After the mechanical parts are processed, the anchor bolts of the main engine and accessories can be filled with quick drying cement, and the reserved holes of the foot bolts at all places can be filled and leveled.
The worktable of the vertical machining center is moved to the exchange position, and the relative position of the pallet station and the exchange table is adjusted, so that the automatic exchange of the worktable is stable, and the maximum load of the worktable is installed for multiple exchanges.
Debugging, prepare various testing tools, such as standard square, precision level, parallel square tube, etc.
Adjust the position of the manipulator to the spindle by manual operation. When the tool holder with the maximum weight is installed in the mold, the automatic exchange between the tool magazine and the spindle position should be carried out for many times to ensure the accuracy and no collision.
Fine adjust the level of the machine tool, so that the geometric accuracy of the vertical machining center can reach the allowable error range. The multi-point cushion support is used to adjust the bed to the level under the free state to ensure the stability of the bed after adjustment.
Check whether the setting parameters of the CNC system and PLC device conform to the specified data in the random data, and then test the main operation functions, safety measures and the execution of common instructions.

CNC machine key function

There are two lights on the power supply of CNC machining center unit, one is the power indicator, which is green; the other is the power alarm light, which is red. The power supply unit here includes the power input unit and the power control part.

First of all, we should know that when the CNC computer gong machining center power can not be connected, if the power indicator (green) is not on. The fuses F1 and F2 of the power supply unit have been blown. This is due to high input voltage, or the components of the power supply unit itself have been damaged.

The input voltage of CNC computer gong machining center is low. Please check the voltage entering the power supply unit. The allowable voltage value is AC 200V + 10%, 50 Hz ± 1Hz. The power supply unit is not good, there is element damage in it. The power indicator light is on, and the alarm light is also gone, but the power supply cannot be connected. This is because the power on condition is not satisfied. By the following switching circuit, the power supply conditions are as follows:

CNC machining center power supply has three conditions: the first point, the source on button closed. Second, the power off button is closed. Third, the external alarm contact is opened.

The alarm light of power supply unit of CNC machining center is on: the fuse of 24 V output voltage is fused, and + 24 V voltage is used on 1.9 “display screen, as shown in the figure below. Check whether + 24 V is short circuited to the ground. 2. The display / manual data input board is poor. During the use of the center, the tool imbalance may occur. If not adjusted in time, it will affect the processing effect. Therefore, we should always pay attention to the tool balance of CNC machining center. What are the main reasons for the imbalance of the handle?

The main reason for CNC machining is that the tool design is asymmetric, there are defects in the tool body, and all the adjustment of the tool. The correct balance of the tool can significantly reduce noise and vibration, which increases the tool life and improves the accuracy consistency of parts.

The centrifugal force of CNC machining center is proportional to the square of velocity to amplify the vibration caused by unbalance. As a result, the vibration of CNC machining center increases, which minimizes the service life of bearing bush, bearing, shaft, spindle and gear.

Before balancing the tool in CNC machining center, it is necessary to measure the unbalance and the angle position of each selected correction plane. These variables are measured on two general types of balancing machines: non rotating or gravity machines are used to measure single plane unbalance, while rotary or centrifuge is used to measure single plane or two plane unbalance.

After measuring the magnitude and angle of the unbalance in the correct plane, you can correct it by adding or removing material from the workpiece. For the components which are not tools, the most widely used material adding method of drilling center is welding counterweight on the components.

CNC machining (CNC machining) refers to the processing with CNC machining tools. The index controlled machine tool is programmed and controlled by NC machining language, usually G code. NC machining G code language tells CNC machine tool which Cartesian position coordinates, and controls the tool feed speed and spindle speed, as well as tool converter, coolant and other functions. Compared with manual machining, CNC machining has great advantages, such as the parts produced by CNC machining are very accurate and repeatable; CNC machining can produce parts with complex shapes that cannot be completed by manual processing. CNC machining technology has been widely promoted, most of the machining workshops have the ability of NC machining. The most common NC machining methods in typical machining workshops are CNC milling, CNC lathe and CNC EDM wire cutting (WEDM). The tool for NC milling is called CNC milling machine or CNC machining center. CNC turning lathe is called CNC lathe center. NC machining G code can be manually programmed, but usually the machining workshop uses CAM software to automatically read CAD file and generate G code program to control NC machine tool.

Computer gong processing – Measurement

3.2. Inspection standards before processing:

3.2.1. Divide the center and read the number. After each division, copy the working coordinates first, and then check again whether the distance from the center to both sides is consistent, to ensure that the center and reading are correct.

3.2.2. Tool selection, tool loading, tool setting and z-axis coordinate reading.

Select the appropriate tool according to the programming list. Clean the cutter head and nozzle thoroughly before installing the tool. After installing the tool, use the calibration table to check whether the tool has deflection. It is necessary to check again after the tool is set and the number is read, so as to avoid the wrong knife, which will bring great loss to the company.

3.2.3. transport program, start processing: before cutting, use single section execution, transfer speed and feed speed to the slowest, slow down the knife, watch the machine tool display Z axis allowance, check whether there is abnormal, if abnormal, press the pause button immediately, find out the reason to solve the anomaly, confirm that after normal, adjust to the right speed to start processing.

3.2.4. In the process of processing, always pay attention to observe whether the processing is abnormal and whether the tool is worn. If the tool wear is serious, the tool grinding shall be suspended to ensure the normal processing.

3.3. Mold kernel processing standards

3.3.1. After getting the drawing and workpiece, check whether the drawing is consistent with the die number of the workpiece.

3.3.2. Measure the actual size of the workpiece with measuring tools.

3.3.3. Check whether the direction of water transportation and reference angle on 2D drawing is consistent with that on the programming list.

3.3.4. Remove the rough edges at the bottom and around the workpiece with a 400 ා oilstone, and wipe the workpiece with cloth scraps.

3.3.5. Place the workpiece on the clamping tool of the machine platform, level the workpiece plane and perpendicularity with parallelism, and the perpendicularity tolerance is within ± 0.015,

Then fix the workpiece firmly and start to divide according to the position marked on the programming list and the size of z-axis collision. (pay attention to whether the edge finder collides with the workpiece during the separation) input the data of the mechanical coordinates x, y, Z into the corresponding coordinates.

3.3.6. According to the programming list, transfer all programs into the computer, simulate with the tool path simulation software, observe the processing area and the highest and lowest depth of processing, and determine the clamping direction, clamping reserved position and tool length of the workpiece.

3.3.7. Install the corresponding tool according to the programming list, and input the tool parameters automatically with the method of automatic tool setting.

3.3.8. Transfer the program to the machine for processing.

3.4. Copper processing standard

3.4.1. After getting the program sheet, find the appropriate copper material according to the mold number, size and quantity of copper on the program sheet.

3.4.2. According to the requirements of the programming list, process the coarse and young products. (the copper material is marked with a code, “a” stands for Yougong, and “B” for coarse material.

3.4.4. Check whether the tool on the program list is consistent with the tool on the machine tool magazine.

The program is simulated with tool path simulation software to observe the processing area and the highest and lowest machining depth to determine the clamping direction, reserved position and tool length of copper male.

3.4.5. Transfer the program to the machine for processing. The workpiece must be prepared for the next machine in the processing, so as to reduce the above preparation time.

3.5. Formwork processing standards

3.6.1. After the workpiece is processed, check whether the shape of the workpiece is consistent with that of the 3D drawing before getting off the machine, and then check whether the workpiece has missed processing, over cutting, and the position of joint connection.

3.6.2. According to the data marked on the programming list, use the calibration table or depth meter to measure the number, and use the needle gauge or plug gauge to measure some matching positions and positioning positions.

3.6.3. Parting surface measurement: according to the data provided by drawings or programmers, detect the coordinates of points (x, y, z) on several parting surfaces, and check whether the parting surface has been processed to the number.

3.6.6. Measure whether the depth of all flat positions reaches the number. For some positions that need to be connected smoothly, the processing shall be improved first, and then the connection shall be carried out slowly after painting the color on the connecting position.

3.6.7. Check all other position data that require CNC machining accuracy and confirm that it is OK before getting off the machine.

3.7 precautions:

3.7.1. Be careful when taking out the tool from the tool holder to avoid scratching fingers.

3.7.2. Do not allow the machine to run fully automatically when using the NC program that has not been tried out.

3.7.3. When the shaft is still rotating, adjust the coolant flow direction with great care.

3.7.4. In case of emergency, press the red emergency button on the controller.

Computer gong processing – knife alignment

The feed machining route of CNC lathe refers to the path that the tool moves from the point of alignment (or fixed origin of machine tool) until it returns to the point and ends the machining procedure, including the path of cutting and the path of cutting tool cutting and cutting out.

The feed route of finishing is basically carried out in the order of the outline of parts. Therefore, the key to determine the feed route is to determine the feed route of rough machining and empty stroke.

In the NC lathe processing, the determination of the processing route should follow the following principles.

① The accuracy and surface roughness of the workpiece to be processed shall be guaranteed.

② The shortest processing route, reducing the time of empty travel and improving the processing efficiency.

③ The work of numerical calculation and the processing procedure are simplified as much as possible.

④ For some reuse programs, subroutines should be used.

CNC advantages and disadvantages CNC machining has the following advantages:

① A large number of tooling is reduced, and complex tooling is not needed for parts with complex shapes. To change the shape and size of parts, only the part processing procedure needs to be modified, which is suitable for the development and modification of new products.

② The machining quality is stable, the processing precision is high, the repetition precision is high, which is suitable for the machining requirements of the aircraft.

③ The production efficiency is high under the condition of multi variety and small batch production, which can reduce the time of production preparation, machine tool adjustment and process inspection, and reduce the cutting time due to the use of the best cutting quantity.

④ The complex profile which can be processed by conventional methods is difficult to process, and even some parts which cannot be observed can be processed.

The disadvantage of NC machining is that the machine tool equipment is expensive, and it requires the maintenance personnel to have a high level.

Computer gong processing — milling head

1、 Computer gong processing — milling head of computer gong:

The milling head part is composed of two parts: a stage (or stepless) gearbox and a milling head. The main shaft of Dongguan high-speed computer gong machining milling head is supported on high-precision bearing to ensure high rotation accuracy and good rigidity of the spindle. The spindle is equipped with a quick tool change nut, and the front cone adopts 105 taper. The spindle adopts mechanical stepless speed change, which has wide adjustment range, stable transmission and convenient operation. The brake mechanism can make the main shaft brake quickly, which can save auxiliary time. When braking, the main shaft can be braked immediately by expanding the stop ring through the brake handle. When starting the main motor, attention should be paid to loosening the spindle brake handle. The milling head part is also equipped with servo motor, inner toothed belt pulley, ball screw pair and spindle sleeve. They form a vertical (Z-direction) feed transmission chain to make the spindle move in a vertical straight line.

The table and the saddle are supported on the wide horizontal guide rail of the lifting table, and the longitudinal feed of the table is driven by a servo motor installed at the right end of the table. The precision ball screw is driven by the inner toothed belt wheel, so that the worktable can obtain longitudinal feed. The left end of the table is equipped with a hand wheel and a dial for manual operation. Turclle B is used on the longitudinal and transverse guide rail surfaces of the bed saddle, so as to improve the wear resistance, stability and accuracy of the guide rail, and eliminate the phenomenon of low-speed crawling.

2、 Computer gong processing: the main functions of computer gong are as follows:

Point position control function the point position control of CNC milling machine is mainly used for hole processing of workpiece, such as center drill positioning, drilling, reaming, countersinking, reaming and boring.
The continuous control function can mill the plane and surface of the workpiece through the linear interpolation, circular interpolation or complex curve interpolation of the CNC milling machine.
Tool radius compensation function of Dongguan mold processing.
If programming directly according to the workpiece contour line, the actual contour line will be larger than the cutter radius value when machining the inner contour of the workpiece; when machining the outer contour of the workpiece, the actual contour line will be reduced by another tool radius value. Using the method of tool radius compensation, the NC system automatically calculates the tool center path, which makes the tool center deviate from the workpiece contour by one tool radius value, so as to process the contour meeting the drawing requirements. By using the function of tool radius compensation, the tool radius compensation can be changed, and the tool wear and machining error can be compensated to realize the rough machining and finish machining of workpiece.
The tool length compensation function can change the compensation amount of tool length. The machining of Dongguan Mechanical parts can compensate the length deviation after tool change, change the plane position of cutting process, and control the axial positioning accuracy of the tool.
The fixed cycle processing function can simplify the processing program and reduce the workload of programming by applying the fixed cycle processing instructions.
Subroutine function if the same or similar parts of the workpiece are processed, it is written into a subroutine, which is called by the main program, so as to simplify the program structure. CNC machining is divided into several modules according to the working procedure of the machining process. Subprograms are written respectively and called by the main program to complete the processing of the workpiece. This modular program is easy to debug and optimize the processing technology.