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Influence of machining process on machining accuracy of parts

March 12, 2019 by jincheng  

Key words: machining process; parts; machining accuracy; influence

In real life, the machinery used in all walks of life is composed of different parts. Whether the accuracy of these parts meets the requirements will directly affect the performance of the mechanical equipment. Therefore, with the improvement of the performance requirements of mechanical equipment, people have put forward higher requirements on the machining accuracy of parts. The machining process has a close relationship with the machining accuracy of the parts. Therefore, it is necessary to analyze the influence of the machining process on the machining accuracy of the parts, so as to better promote the development of the machining manufacturing industry.

 

A machining process and precision parts

 

1.1 Mechanical Processing Overview

 

The so-called machining process is actually a method of making blanks into mechanical parts and workpieces by using relevant process technology. It is a machining process that matches the blanks with the parts. In the process of processing, it is necessary to make the blank grinding and the processing of the parts to meet certain precision requirements. In general, it is necessary to finish the roughing of the part before finishing the part. Among them, roughing is the general grinding of blanks and parts, and it is necessary to make the processed blanks and parts close to the processing requirements. Finishing requires precise calculations to achieve maximum fit between the blank and the part.

 

1.2 Relationship between processing and processing precision machine parts

 

After the machining is completed, the corresponding inspection work needs to be carried out in order to eliminate the parts that do not meet the specified error range. Whether the machining process is rigorous will directly affect whether the machining accuracy of the parts can meet the processing requirements. Therefore, the machining process is actually a procedure for transforming the blank into a qualified part, and has strict requirements on the machining accuracy of the part. In the whole process of processing, the strict implementation of the machining process needs to be carried out in accordance with the relevant normative standards, so as to avoid the inaccuracy of the machining accuracy of the parts caused by external factors. At present, the machining process is more diverse, but the precision of part processing is also increasing. The improvement of the machining accuracy of the parts can also reflect the precision of the machining process [1]. Therefore, it is also necessary to understand the influence of the machining process on the machining accuracy of the parts, and thus seek ways to carry out the refinement and improvement of the machining process, and then the machining accuracy of the parts is effectively improved.

 

2 Influence of machining process on machining accuracy of parts

 

2.1 The effect of CNC programming on the machining accuracy of parts

In the process of machining parts using a machining process, it is necessary to control the machine tool through numerical control programming. CNC technology always regards high precision as the goal pursued, so the numerical control process will have an important impact on the machining accuracy of parts. First, the choice of programming origin is required at the beginning of NC programming. The ability to properly select the origin will directly affect the machining accuracy of the part. Because the selection of the programming origin is properly performed, machining errors due to dimensional tolerance conversion can be avoided. Secondly, the data needs to be processed during programming, and whether the data can be processed reasonably will affect the processing accuracy of the contour trace of the part. In this step, you also need to do an unknown programming node for calculation. Moreover, CNC programming also needs to choose a reasonable processing route. The selection of the machining route of the parts will directly affect the machining efficiency and accuracy of the parts. In addition, in the process of machining parts, if the selected interpolation method is improper, it will affect the machining accuracy of the parts. At the same time, no matter which interpolation method is used, the error will be accumulated [2]. After the error has accumulated to a certain extent, the machine tool will have positioning errors and movements, which will affect the machining accuracy of the parts. Therefore, it is necessary to perform interpolation operations in the NC programming process in order to better control the machining accuracy of the parts.

 

2.2 The influence of geometric accuracy on the machining accuracy of parts

In the process of part processing, the processes of cutting and grinding need to be done manually, so it is basically difficult to achieve the same. In this case, geometrical parameter errors will occur in the machining of the part, which will affect the machining accuracy of the part. On the one hand, the use of tools is required during the machining process, so the accuracy of the tools will have an important impact on the machining accuracy of the parts. When cutting with a tool, the tool will be subject to wear due to the frictional action of the blade, the blade and the workpiece. After a certain degree of wear, the friction value of the surface of the workpiece increases, causing the tool to vibrate during the cutting process and eventually causing a change in the shape of the cutting. In order to solve this problem, the installation accuracy and wear resistance of the tool are also improved. At the same time, it is necessary to strengthen the tool maintenance in daily work and use the compensation device for wear compensation. On the other hand, the continuous operation of machined machine tools will cause the spindle to have a rotation error. In the case where the main shaft deviates from the standard central axis, there will be some error in the machining of the parts [3]. Because the machine tool spindle rotation force can control the relative position of the parts processing, the spindle deviation will directly affect the surface smoothness of the part. In order to solve this problem, it is necessary to strictly carry out the assembly of the machine tool spindle and strengthen the maintenance in daily work.

 

2.3 Influence of force deformation on machining accuracy of parts

In the process of machining, it involves the movement of the four components of the machine tool, workpiece, tool and fixture, so the system will withstand various forces such as clamp clamping force, workpiece gravity and tool cutting force. Under the combined effect of force, fatigue deformation will occur inside the system, thus forming a certain processing error. For the time being, these forces can be divided into two types, namely, processing external forces and residual stresses.

Under the action of different external forces, the machining accuracy of the parts will also be affected differently. For example, in the case where the rigidity of the arbor is smaller than the rigidity of the outer turning tool, the difference in rigidity between the shank causes deformation of the arbor, thereby affecting the accuracy of the hole of the part. When the tool and machine tool stiffness is much larger than the workpiece, the part will be deformed. Due to the pressure of the machine itself, it also has a rigid change, and the machining accuracy of the parts is affected [4]. In order to prevent the machining error of parts caused by external forces, it is also necessary to reduce the degree of stress on the system load and to solve the weak points of the system. Specifically, it is the choice of processing materials and machine tools to improve the stability and service life of the system.

During the machining of the part, it will generate some residual stress. For example, when the parts are cast and forged after cooling, the previously generated blank stress will cause different cooling shrinkage speeds in the parts where the thickness is uneven or the structure is complicated. In the case of internal stress generation, the machining accuracy of the part is affected. In order to solve this problem, it is also necessary to use natural aging and artificial aging to eliminate residual stress. Specifically, the formed blank is placed for a period of time after the part is cast and forged. During this time, as the temperature decreases, the stress inside the part will gradually disappear. For artificial aging, the machined parts need to be reheated and then cooled with the furnace at a certain temperature. In addition to using the thermal cooling method, the vibration device can also be used to resonate the parts to eliminate the internal stress of the part.

 

2.4 Influence of thermal deformation on machining accuracy of parts

A large amount of heat is generated during the processing of the part, which causes the system to heat and deform and affect the machining accuracy of the part. First, the workpiece will deform under thermal erosion, which will affect the accuracy of the workpiece. In response to this problem, it is also necessary to use a coolant to prevent thermal deformation of the workpiece. Secondly, the tool generates a lot of heat during the cutting process, which causes the tool to be thermally deformed. To avoid this problem, coolant and lubricant are also needed to speed up tool cooling. In addition, the machine tool will also undergo thermal deformation when the heat source is unevenly walked and the structure is complicated, and corresponding measures must be taken for control.

 

3 Conclusion

All in all, in the process of parts processing, the influence of the machining process on the machining accuracy of the parts should be recognized, and a reasonable way to improve the machining process is sought, and then the machining accuracy of the parts is improved.

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Experimental study on efficient milling of casing parts

March 7, 2019 by jincheng  

Key words: machine parts; high-altitude milling; experimental study

The high-pressure turbine of the part of the Rollo company BR710 engine studied in this paper has a long problem in production management due to the long processing time of the milling process, low equipment power and long-term occupation of the five-axis machining center. While recognizing the problem, he conducted special research and conducted experimental research on two of the long processing times. The main content of the experiment is how to select the appropriate machining tool and determine the parameters suitable for processing the part. Parameters, reducing processing time and reducing processing costs. The specific details of the experiment of the 60 process and the 80 process are specifically described below.

 

I. Experimental study on the inner lace of No.60 process milling

The machining allowance of this process is 10mm. The original processing method is used to select Φ20R3 end mill for layered processing. Each layer is 3mm, and the unilateral side is 0.25mm. The processing time is long and the props are wasted. In order to ensure the quality of the parts. Under the premise, improve the processing efficiency, roughing to Φ100 corn milling cutter, non-standard knife body, blade: SPMT100408-RIC328, processing parameters are V = 30m / min, F = 40m / min. Firstly, the rough milling and two knives were used to complete the machining. During the machining process, the cutting was very smooth, and the blade wear was small after machining. Based on this, the test completed the rough machining of the part, and changed the machining mode into the tangential arc. The earth improves the processing efficiency, and the tool wear is serious after processing, and the next part can be processed after being replaced.

 

Second, No.80 process rough milling large end external profile test study

This process is the main rough milling process of the parts. It has many margins and is easy to be deformed. It adopts special tools for outsourcing, with internal support, and requires a force-limiting wrench for pressing. The pressing force of the pressing plate is 80NM, and the internal support is 30NM.

 

The following is a description of the specific speed-up content and improvement content according to the work steps:

(1) Application of ceramic tools in rough milling

The maximum amount of parts in this process is 7mm. The rough machining experiment has adopted ceramic blades, and the rough machining has a left side of 0.5mm. The ceramic blade is characterized by high strength, high hardness, high red hardness, high wear resistance, excellent chemical stability and low friction coefficient, and its cutting processing efficiency is 6 to 10 times that of ordinary cemented carbide tools. In the case of high-speed milling with modern ceramic inserts, it is essential to select the cutting speed, feed rate, depth of cut, width and tool type for the purpose of improving tool life and productivity. Therefore, in the application, you must pay attention to the following aspects:

 

1 machine tool requirements

Machine tool-parts-tools, the weak rigidity of the process system is the main reason for the reduction or collapse of the ceramic tool life. The rigidity of the machine tool cannot be considered simply. The rigidity of the parts, fixtures and tools must be considered at the same time. The DMU210P five-coordinate machining center used in the machining of this part has good rigidity, sufficient power and high number of revolutions. The external auxiliary fixture is used to add internal auxiliary support to the machining area, which reduces the stress generated during the machining process and causes the parts to be Deformation.

 

2 reasonable NC program

When using ceramic tools for high-speed milling, the milling method is usually used. When the internal profile is machined, when the tool is cut to the corner, the cycloidal cutting method is adopted to avoid sudden increase of the cutting force. High-speed cutting mainly adopts circuit cutting, which reduces the cutting in and cutting times of the tool through the uninterrupted cutting process and tool path, and obtains a stable, high-efficiency and high-precision cutting process.

 

3 selection of reasonable geometric parameters of ceramic tools

When selecting the reasonable processing parameters of the ceramic tool, it must be considered that the ceramic tool is a hard and brittle tool. How to ensure the stability of its use and the absence of chipping is an important basis for selecting the reasonable processing parameters of the ceramic tool; The continuity, economy and smoothness of the intermediate ring material milling are to be considered.

 

(2) Switch to face milling cutter finishing belt

The original finished intermediate ring belt was milled up and down using a Ф20R3 hard milling cutter. The surface of the milled island was milled up and down using a 16 full-end milling cutter. The disadvantage of this machining is that the high hardness of the part is high, and the machining cost is high. time. Later, the 50R6 face milling cutter was used to finish the middle ring belt and the Ф40R5 face milling cutter to mill the island surface. However, after machining with these two types of milling cutters, it was found that the surface of the machined parts was not the same height, and the height difference was 0.2 mm. Since the middle part of the tool was not machined, the surface height after machining was different. In view of this situation, using eccentric milling, taking the Ф50R6 face milling cutter as an example, the highest point of the cutting edge is at Ф35, and the cutting can not be performed in the middle of the tool. After the eccentricity is 12.5mm, the surface of the machined parts is 0.03mm. Left and right, meet the requirements of the design drawings.

 

(3) Use of U drill

Since the U-drill has not been used before, the hole is usually machined according to the traditional machining method. Dot-drill-ream-boring-reaming, for some large diameter holes and tolerances and position degrees It is not a very strict hole, and it takes a lot of time to process. The outer part of this part is recommended to use U-drill to machine the hole on the island.

First, let's briefly introduce the processing characteristics of U-drill:

 

1 processing efficiency is generally 2 to 3 times that of ordinary drills.

The 2U drill can be machined directly on the workpiece without the need to drill the pilot hole in the center.

3 The front end of the cutter body is equipped with a replaceable blade, which reduces the cost of use.

The difference between a 4U drill and a conventional drill bit is that the U-drill uses a blade - a peripheral blade and a center blade. After the tool is worn, the blade can be directly replaced without re-grinding. The use of the indexable blade saves material compared to the overall hard drill, and the blade is consistent. It's easier to control part size.

 

The 5U drill has good rigidity and can adopt a high feed rate, and the machining diameter of the U drill is much larger than that of the ordinary drill bit, and the maximum can reach Ф50mm~Ф60mm. Of course, the U drill cannot be made too small due to the characteristics of the insert blade. U diamonds below 10mm are rare.

 

6U drills need to replace the same type of different types of blades when encountering various materials. Other drill bits should be selected according to different materials.

 

7 Compared with hard drills, the accuracy of the hole drilled by U drill is still higher, and the finish is better, especially when the cooling and lubrication are not smooth, and the U drill can correct the position accuracy of the hole, and the ordinary drill bit will not work.

 

The dimensions of the holes on the island to be processed in this process are Ф20, Ф22, Ф29, Ф32, respectively. The original Ф16 drill bit is used to drill the bottom hole, and then the Ф16 milling cutter is used for layer milling, and the holes are sequentially machined to the size. The point is not good, one is a waste of time, respectively, the hole is milled from Ф16 to Ф19, Ф21, Ф28, Ф31, which needs to remove a lot of margin; the second is to waste the tool, using a solid carbide milling cutter to layer the hole, Moreover, the margin is large, the tool wears quickly, and the cost increases. Third, there is a quality hazard in the machining. When milling the hole, the operator needs to calculate the tool compensation value and input it into the machine tool, so that the artificial operation is easy to generate errors. The advantages of CNC machine tools are not fully utilized, and it is easy to cause the parts to be out of size.

 

Conclusion

 

In this paper, through the research on the two milling operations of the parts, the processing efficiency is improved, the precious production time is saved for the factory, and the processing cost is also reduced, which lays a foundation for the mass production in the future.

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Brief Discussion on Thread Milling

March 6, 2019 by jincheng  

The emergence of a three-axis linkage CNC machining system enables thread milling.

 

First, the seven contrasts with traditional tapping

 

First, the tap (screw) can only process fixed pitch, and the thread milling cutter can machine threads with different pitches. Second, when machining blind holes, the tap can only reach a certain depth. A thread milling cutter with a flat bottom actually has no "guide cone" and can process deeper complete threads. Third, thread milling cutters can machine threads with special fits, tolerances or positions, and standard taps cannot. Fourth, the thread milling cutter can machine a variety of internal and external threads with different directions of rotation (left-handed, right-handed). For threads that do not allow transitional or undercut structures, traditional turning methods or taps and dies are difficult to machine, but CNC milling is very easy to implement. Fifth, when machining the internal thread with a tap, it is necessary to ream the taper of 1 degree and 47 minutes after drilling, and then use a head tapping tap to open a guide. If it is a blind hole, the third tapping cone is also required. Milling does not require a reaming hole in most cases. Sixth, the continuous length of swarf generated by tapping on certain materials can be entangled in the hole or piled up at the bottom of the blind hole to cause the tap to break. Thread milling is an interrupted cut that produces short, shredded chips with sufficient space between the tool and the hole to allow the chips to be easily discharged without chipping. Seventh, when tapping, due to poor tap performance or difficult material processing, the processed thread is easily out of tolerance. Thread milling, especially for difficult-to-machine materials, does not have the problem of excessive thread size. The thread size is controlled by the machining cycle (program value) and the tool offset value, and the surface quality of the milled thread is also significantly better than tapping. By cutting a threaded hole and a tapped hole and observing the result under a magnifying glass, it is easy to see that the tapped hole appears to be a little flash because the cutting edge of the tap tends to be blocked and sometimes at the time of tapping. Biting the tap sometimes tears the thread, causing defects in the tooth shape; eighth, once the tap breaks in the threaded hole being machined, it is quite difficult to remove the broken tap from the threaded hole, especially for very expensive materials. It will cause great economic losses. This is not the case after the thread milling cutter has been broken.

Second, the type of thread milling cutter

 

1. Overall cylindrical thread milling cutter

Commonly used integral cylindrical thread milling cutters can be divided into two types: machining coarse thread and machining fine thread. Thread milling cutters are made of hard alloy and can be coated with various coatings (such as TiCN, TiAlCN, WC, etc.) to increase tool life. Suitable for milling small and medium diameter threads of steel, cast iron and non-metallic materials, with smooth cutting and long life. Table 1 shows the standard thread pitch P of common specifications.

 

2. Machine clamp thread milling cutter

Machine clamp thread milling cutters are suitable for threading of larger diameters (generally 25mm or more in diameter). The jaws are divided into two types from the tooth profile: single-toothed blades and multi-toothed blades. The tool path when milling threads is basically the same.

Third, the programming and processing of milling threads

The thread milling movement path is a spiral, which can be realized by the three-axis linkage of the CNC machine tool.

1. Single-thread thread milling cutter milling internal thread circulation (FANUC system)

O2345;

#1=;Thread nominal diameter

#2=;pitch

#3=[1.1*#2]/2; thread depth

#4=; Milling cutter diameter

#5=;Thread depth

#6=;feed speed

#7=[#1-#4]/2.+#3; Blade radius of gyration

#8= 0 ;variable

G54 G90 G21;

GOO Z5O.;

XO YO;

M03 S600;

G01 X#7 F#6;

WHILE[#8GT-#5]DO 1;

G00 Z#8;

#8=#8-#2

G02I-#7 Z#2; left-handed with G03

END 1;

G00 XO YO;

Z50.;

M30;

 

2. Single-blade thread milling cutter milling external thread circulation (FANUC system)

O3456;

#1=;Thread nominal diameter

#2=;pitch

#3=[1.1*#2]/2; thread depth

#4=; Milling cutter diameter

#5=;Thread depth

#6=;feed speed

#7=[#1+#4]/2.-#3 ;

#8= 0 ;variable

G54 G90 G21;

GOO Z5O.;

XO YO;

M03 S600;

G01 X#7 F#6;

WHILE[#8GT-#5]DO 1;

G00 Z#8;

#8=#8-#2

G02I-#7 Z#2; left-handed with G03

END 1;

G00 XO YO;

Z50.;

M30;

 

Thread milling also has limitations:

First, it is necessary to use a 3-axis CNC machine tool; second, it can only process 3 times the diameter of the thread; third, the thread milling cutter is more expensive than the tap; fourth, the programming of the thread milling is more troublesome.

 

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Cause analysis and preventive measures for the problem of easy milling

March 5, 2019 by jincheng  

The problem of high frequency during milling is the problem of the tool and the quality of the workpiece. The tool problem is mainly caused by the formation of crater on the rake face, the viscous edge of the blade, the hot crack of the blade, the deformation of the cutter tooth, etc. The quality of the workpiece is mainly manifested in the work of milling to produce scales, the workpiece to produce chill layer, surface roughness parameters. The values ​​are too large, the geometric error is out of tolerance, and the geometrical tolerances are out of tolerance. The following are the analysis of possible problems in these processes, and propose methods and measures to prevent these problems.

1 Probable causes and precautions for tools used in milling

(1) The rake face is produced by the rake face. When the blade is welded to the chip, the rake face is prone to crater, and this problem is avoided. Wear-resistant blades, coated alloy blades, reduced milling depth or milling load, and larger milling cutter rake angle should be used. (2) Edge edge sticky swarf. The ever-changing vibration load causes an increase in the milling force and the milling temperature, and the edges are susceptible to sticking. In order to avoid this problem, the oil should be polished with the oil on the cutting edge arc or chamfer, change the alloy grade to increase the blade strength, reduce the feed per tooth, reduce the milling speed when milling hard materials, use sufficient lubrication and cooling. Good cutting fluid; (3) hot cracking of the cutter. During the milling process, when the temperature changes rapidly at high temperature, the teeth are prone to hot cracking, and the hot cracks of the teeth are avoided. The alloy grade should be changed, the milling speed should be reduced, and the cutting fluid should be used appropriately; (4) The cutter teeth are deformed. When the milling temperature in the milling area is too high, the teeth are easily deformed, and the deformation of the teeth is avoided. The anti-deformation and anti-wear blades should be used, the cutting fluid should be properly used, the milling speed and the feed per tooth should be reduced. (5) The edge is notched or sunken. When the blade is subjected to tensile and compressive stress and the hardened material blade is oxidized, the blade edge is notched or sagged. To avoid this defect, the milling angle should be increased, the blade cutting edge should be polished with oil stone, and each tooth can be lowered. (6) The plated blade is broken or the blade is split. During the milling process, if the milling force is too high, it is easy to break the plated blade or the blade is cracked. To avoid this problem, anti-vibration alloy grade inserts, high-intensity negative-angle milling cutters, and thicker use should be used. Blades, knives, reduced feed or milling depth, check that the inserts are all in contact; (7) excessive wear or wear on the edges. In the case of milling, if there is grinding, mechanical vibration and chemical reaction, it is easy to cause excessive wear or wear of the cutting edge. To prevent this problem, anti-wear alloy grade inserts should be used, the milling speed should be reduced, the feed rate should be increased, and the feed rate can be increased. Sharpen or replace the blade; (8) Cutter slag in the milling cutter. If abnormal chips or chip pockets are too small, the cutter flutes are easy to slag. To avoid slagging in the flutes, increase the chip space and flutes, and polish the flutes when milling aluminum alloy. .

2 Causes and precautions for problems in the quality of workpieces during milling

(1) During milling, the workpiece produces scales. In milling, if the milling force and milling temperature are too high, the workpiece is prone to scales. The method of avoiding scale formation is to increase the milling speed, change the tool geometry angle and increase the rake angle for the soft material and hard material below 34~38HRC. And keep the edge sharp, using coated blades.

(2) The workpiece produces a chill layer. When the milling cutter is blunt and the milling thickness is too small, the workpiece is prone to produce a chill layer. To avoid chilling and hardening of the workpiece, the blade should be sharpened or replaced, the feed per tooth should be increased, the down-milling should be used, and the larger positive rake angle milling should be used. Knife.

(3) The surface roughness parameter value is too large. When milling the workpiece, if the milling amount is too large, the vibration is generated during milling, the milling cutter is beating, and the milling cutter is blunt, the surface quality of the workpiece is degraded. To improve the surface quality of the workpiece during milling, the following measures should be taken: Amount; use a wide-blade large-arc repairing tooth milling cutter; check the workbench strip to eliminate the gap and other moving parts; check the spindle hole and the arbor and the shank and the milling cutter; eliminate the gap or Add inertia flywheel on the arbor; check the cutter teeth to jump, adjust or replace the blade, grind the cutting edge with oil stone, reduce the edge roughness parameter value; sharpen and replace the edge or blade of the indexable insert, keep the blade Sharp mouth; when milling the side, use a wrong tooth with a backlash angle or a three-sided milling cutter.

(4) The flatness is out of tolerance. When the workpiece is deformed during milling, the axis of the milling cutter and the workpiece are not perpendicular to the workpiece, the flatness of the workpiece cannot be guaranteed. To ensure that the flatness of the workpiece is not exceeded after the workpiece is processed, the following precautions should be taken: Clamping force to avoid deformation; check whether the clamping point is at the best position of the workpiece; add a lockable auxiliary support at the appropriate position of the workpiece to improve the rigidity of the workpiece; check whether the positioning base has burrs or debris, Whether all contact; in the process of installation and clamping of the workpiece, the principle of clamping from the middle to the side or diagonally should be avoided to avoid the deformation of the workpiece due to improper clamping sequence; reduce the milling depth αp and reduce the milling speed ν Increase the feed rate αf, use small margin, low speed and large feed milling to minimize the temperature change of the workpiece during milling; before finishing the milling, relax the workpiece and then clamp to eliminate the deformation of the workpiece during finishing milling; Calibrate the perpendicularity of the milling cutter axis to the workpiece plane to avoid undercutting when the workpiece surface is milled.

(5) The verticality is out of tolerance. When the end mill has a small diameter or vibration, swing or three-sided milling cutter perpendicular to the axis feeding the milling side, the rigidity of the tool bar is insufficient, the vertical tolerance of the workpiece can not be guaranteed, in order to avoid this situation, Take the following measures: select an end mill with a large diameter and good rigidity; check the coaxiality of the cutter sleeve or the collet with the main shaft and the coaxiality between the inner and outer circles, and eliminate the skew that may occur during installation; Small feed rate or increase milling speed; appropriately reduce the diameter of the three-sided milling cutter, increase the diameter of the cutter bar, and reduce the feed amount to reduce the bending deformation of the cutter bar.

(6) The size is out of tolerance. During milling, if the tool such as end mill, keyway cutter, and three-sided milling cutter oscillates itself, it will cause the workpiece to be out of size. If the qualified workpiece size is pre-guaranteed, check whether the cutter meets the pattern requirements after sharpening. Replace the worn tool in time, check whether the swing after the milling cutter is installed exceeds the accuracy requirement range, check whether the milling cutter bar is bent, and check whether the end face between the milling cutter and the tool bar sleeve is flat or perpendicular to the axis.

In the milling process, in order to ensure the surface quality, shape tolerance and dimensional tolerance of the workpiece, it is necessary to pay attention to the problems that may occur during the machining. Prepare the plan before machining, select the appropriate tool, and correctly install the tool and workpiece. Determine the scientific and reasonable cutting process parameters, properly use the cutting fluid to control the temperature of the processing area, ensure the smooth discharge of the chips, and fully prepare for the qualified workpieces to improve the processing efficiency, save production costs, and create greater for the enterprise. Economic benefits.

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Identify key challenges in milling routing

March 4, 2019 by jincheng  

1) It should be able to ensure the precision and surface roughness of the parts in the milling process.

2) The tool movement path should be the shortest, the tool idle travel time should be reduced, and the machining efficiency should be improved.

3) The numerical calculation should be simple and the number of blocks should be small to reduce the programming workload.

 

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