In recent years, the global aerospace industry has made remarkable achievements, which cannot be separated from the important support of CNCM machining technology. As an efficient and high-precision machining method, CNCM technology is increasingly widely used in the aerospace field, which provides a strong guarantee for the performance improvement of aerospace equipment.

According to international market research institutions, the global aerospace market size will maintain steady growth in the next decade and is expected to reach about $200 billion by 2028. In China, the size of the aerospace market is also continuing to expand and is expected to reach about 250 billion yuan by 2026. In this context, the application of CNCM machining technology in the aerospace industry is particularly important.

It is understood that CNC machining technology in the aerospace field can produce accurate, precise, complex parts, such as aircraft engines, turbine blades, aircraft structural parts, etc. These components need to have high accuracy and stability to ensure the safety and performance of aerospace spacecraft. According to relevant data, the global aerospace parts market is expected to reach about $12 billion by 2026.

In addition, the high efficiency of CNC machining technology in the aerospace field has also been widely used. In the assembly process of large aerospace spacecraft such as aircraft and rockets, CNC machining technology can achieve rapid and mass production and improve production efficiency. According to statistics, the global aerospace assembly market size is expected to reach about $60 billion by 2026.

In terms of materials, the compatibility of CNC machining technology in the aerospace field has been fully reflected. With the increasing application of new materials in the aerospace field, such as carbon fiber composite materials, titanium alloys, etc., CNC machining technology can realize the efficient processing of these materials to ensure the performance and quality of parts. According to statistics, the global aerospace materials market size is expected to reach about $35 billion by 2026.

It is worth mentioning that CNC machining technology also supports the manufacture of customized parts in the aerospace sector. This is of great significance for the manufacture of aerospace spacecraft in special scenarios. According to statistics, the global aerospace custom parts market size is expected to reach about $2.5 billion by 2026.

In summary, the application of CNCM machining technology in the aerospace industry provides a strong guarantee for the performance improvement of aerospace equipment. In the context of the rapid development of China's aerospace industry, the importance of CNC machining technology is self-evident. With the continuous expansion of the aerospace market, the application prospect of CNC machining technology in the aerospace industry will be broader. We have reason to believe that CNC machining technology will continue to help the prosperity of aerospace industry.

In the field of machining industry, the precision size control of drawings plays a vital role, which directly affects the assembly performance and quality of mechanical equipment. The main factor affecting the size of precision machining is the error problem, because the error problem is affected by a variety of factors, in the machine precision machining will inevitably appear a variety of error problems, so only the use of various technical measures, the precision control in a scientific range. This requires technical personnel to strictly process according to the production drawings, and strictly require the machining process flow, so as to ensure the accuracy of the size of the precision machining production drawings to the greatest extent.



Today, with the rapid development of social economy and industrial reform, the role played by precision machining has become more and more important, and China's machining industry has also made great progress, not only the quality has been greatly improved, but also greatly expanded in the scale of production. With the development of the industrialization process, the precision of precision machining is also more and more attention, therefore, it is necessary to strengthen the control of precision in the process of machining (precision machining process, the control of precision must be attached great importance, and take reasonable technical measures to solve the problems.



Content of machining and influencing factors







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Understand the content of machining



In the field of mechanical processing in China, there is a clear definition of the accuracy of mechanical processing, which refers to the professional and technical personnel after the completion of the processing of mechanical parts, the use of instruments to detect the position of the parts, shape, size and related data, so as to determine the degree of compliance of the parts. Generally speaking, the main factor affecting the accuracy of machining is the various errors generated in machining, and the operators and technical units of technical processing must attach great importance to this problem. In machining, the control and grasp of precision are obviously related to the error problem of machining. Machining error is mainly reflected by the shape, size and position, it is through the use of mechanical size control to achieve the purpose of controlling the precision of machining, in ensuring the surface quality of machining, the machining size error control within a reasonable range. In the process of machining, due to the impact of the benchmark and the machining surface, it will cause the deviation of the position of the precision parts, so the verticality, position and parallelism of the precision machining must be strictly controlled.



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/ Factors affecting precision machining accuracy




In the process of precision machining, there are strict requirements for various production technologies and production processes, so as to reduce or even eliminate the purpose of machining technology errors. In machining, the error between the spindle rotation is an important factor affecting the accuracy. In the process of modern mechanical production and processing, the error caused by the spindle rotation problem is very obvious, which is more obvious in high-tech and high-precision products, which is also an important factor affecting the processing. For the resulting error, the error can be reduced by processing and transforming the machinery. In addition, bearings with higher precision can also be used, which can also significantly reduce the resulting error.



In addition to the error caused by the spindle rotation, the error caused by the problem of the fixture and the tool can not be ignored. Due to the requirements of production, machining manufacturers will renovate the size, type and model of fixtures and tools to a certain extent, which will have a greater impact on the accuracy of machining. In the actual processing process, the size of the fixture and the tool are fixed, which makes it impossible to adjust the size of the fixture and the tool in the process of production and processing. This will cause a certain error flow in the mechanical processing when the technical parameters and the working environment change.

In addition, due to the process of using and installing fixtures and tools, the position of fixtures and tools will be changed, resulting in errors. Of course, the cutting force will also have a certain impact on the machining, resulting in the generation of errors, and ultimately the accuracy of the machining. Due to the influence of the external environment and temperature, the machined parts can easily affect the cutting force. The greater accuracy error is caused by the local change of the process system and the overall deformation. In the process of mechanical production and processing, if the change of the direction of the tightening degree and the insufficient stiffness of the parts are affected, the deformation of the machined parts will be caused, and the machining will produce a lot of errors, which will affect the precision control of the machining.







Technical measures to control machining accuracy




In the process of mechanical production and processing, the problem of processing accuracy must be strictly controlled, and the accuracy problem must be comprehensively considered, so the processing accuracy of each part must be greatly improved, so as to improve the accuracy of the entire mechanical equipment. In the process of machining, the original error plays an important role in ensuring the quality of machining. For mechanical components, it is necessary to classify them according to the requirements of relevant regulations, according to the material, type, model, size and use, and then develop a certain accuracy range, and control the precision error of the machined parts within this range. For the technical staff, it is necessary to determine a reasonable range of the error generated in the machining, and make reasonable adjustments to the fixture and the tool, so as to control the error within this reasonable range, and ultimately reduce the error of the part to the greatest extent. Only by controlling the errors in machining, can the precision control of machining be achieved to the maximum extent, so as to achieve the purpose of improving the precision of machining.

Compensating error method

Error compensation method refers to the use of processing means to achieve error compensation after the machining of mechanical parts, so as to achieve the purpose of reducing the error in the processing of parts. Compensation error method is a very important technical measure to solve the stiffness problem of the process. The main principle is to compensate the original error by creating a new error, so as to improve the precision control level in precision machining. Error compensation method is an important means to reduce the machining error, which has been widely used in practice at home and abroad. In domestic regulations, the original error is generally represented by a negative number, and the compensation error is specified as a positive number, so that when the original error and the compensation error are closer to zero, the smaller the machining error.



Of course, the methods of reducing errors and improving precision control are not only these two, but also the transfer error method is a more commonly used method of reducing errors. Therefore, in the actual production process, it is necessary to choose a reasonable method to reduce the error according to different situations, so as to achieve the best precision control and promote the continuous and stable development of precision machining.

General steps of plastic parts designPlastic parts are designed on the basis of industrial modeling. First, see whether there are similar products for reference, and then carry out detailed functional decomposition of products and parts to determine the main process problems such as parts folding, wall thickness, demoulding slope, transition treatment between parts, connection treatment and strength treatment of parts.1. Similar reference


Before design, first look for similar products of the company and peers, what problems and deficiencies have occurred in the original products, and refer to the existing mature structure to avoid problematic structural forms.2. Determine the part discount, transition, connection and clearance treatment between partsUnderstand the modeling style from the modeling drawing and effect drawing, cooperate with the functional decomposition of the product, determine the number of parts (different surface states are either divided into different parts, or there must be over treatment between different surfaces), determine the over treatment between parts' surfaces, and determine the connection mode and fit clearance between parts.
3. Determination of part strength and connection strengthDetermine the wall thickness of the part body according to the product size. The strength of the part itself is determined by the wall thickness of the plastic part, the structural form (the plastic part in the shape of a flat plate has the worst strength), the stiffener and the stiffener. While determining the single strength of parts, the connection strength between parts must be determined. The methods to change the connection strength include: adding screw column, adding stop, adding buckle position and adding reinforcing bone against top and bottom.4. Determination of demoulding slope
The demoulding slope shall be comprehensively determined according to the material (PP, PE silica gel and rubber can be demoulded forcibly), surface state (the slope of decorative grain shall be greater than that of smooth surface, and the slope of etched surface shall be 0.5 degrees greater than that required by the template as far as possible, so as to ensure that the etched surface will not be damaged and improve the yield of products), transparency or not determines the demoulding slope of parts (the transparent slope shall be greater).Material types recommended by different product series of the companySurface treatment of plastic parts
Wall thickness selection of plastic partsFor plastic parts, the uniformity of wall thickness is required, and the workpiece with uneven wall thickness will have shrinkage traces. It is required that the ratio of stiffener to main wall thickness should be less than 0.4, and the maximum ratio should not exceed 0.6.Demoulding slope of plastic parts
In the construction of stereoscopic drawing, where the appearance and assembly are affected, the slope needs to be drawn, and the slope is generally not drawn for stiffeners.The demoulding slope of plastic parts is determined by the material, surface decoration status and whether the parts are transparent or not. The demoulding slope of hard plastic is greater than that of soft plastic. The higher the part, the deeper the hole, and the smaller the slope.Recommended demoulding slope for different materials
Numerical values of different accuracy in different size rangesDimensional accuracy of plastic partsGenerally, the accuracy of plastic parts is not high. In practical use, we mainly check the assembly dimensions, and mainly mark the overall dimensions, assembly dimensions and other dimensions that need to be controlled on the plan.
In practice, we mainly consider the consistency of dimensions. The edges of the upper and lower covers need to be aligned.Economic accuracy of different materialsNumerical values of different accuracy in different size ranges
Surface roughness of plastics1) The roughness of the etched surface cannot be marked. Where the plastic surface finish is particularly high, circle this range and mark the surface state as mirror.2) The surface of plastic parts is generally smooth and bright, and the surface roughness is generally ra2.5 0.2um.
3) The surface roughness of plastic mainly depends on the surface roughness of mold cavity. The surface roughness of mold is required to be one to two levels higher than that of plastic parts. The mold surface can reach ra0.05 by ultrasonic and electrolytic polishing.FilletThe fillet value of injection molding is determined by the adjacent wall thickness, generally 0.5 1.5 times of the wall thickness, but not less than 0.5mm.
The position of the parting surface shall be carefully selected. There is a fillet on the parting surface, and the fillet part shall be on the other side of the die. It is difficult to make, and there are fine trace lines at the fillet. However, fillet is required when anti cutting hand is required.Stiffener problemThe injection molding process is similar to the casting process. The non-uniformity of wall thickness will produce shrinkage defects. Generally, the wall thickness of reinforcement is 0.4 times of the main body thickness, and the maximum is no more than 0.6 times. The spacing between bars is greater than 4T, and the height of bars is less than 3T. In the method of improving the strength of parts, it is generally reinforced without increasing the wall thickness.
The reinforcement of the screw column shall be at least 1.0mm lower than the end face of the column, and the reinforcement shall be at least 1.0mm lower than the part surface or the parting surface.When multiple bars intersect, pay attention to the non-uniformity of wall thickness caused by the intersection.Design of stiffeners for plastic parts
Bearing surfacePlastic is easy to deform. In terms of positioning, it should be classified as the positioning of wool embryo. In terms of positioning area, it should be small. For example, the support of plane should be changed into small convex points and convex rings.Oblique roof and row position
The inclined top and row position move in the parting direction and perpendicular to the parting direction. The inclined top and row position shall be perpendicular to the parting direction, and there shall be sufficient movement space, as shown in the following figure:Treatment of plastic limit process problems1) Special treatment of wall thickness
For particularly large workpieces, such as the shell of toy cars, the wall thickness can be relatively thin by using the method of multi-point glue feeding. The local glue position of the column is thick, which is treated as shown in the following figure.Special treatment of wall thickness2) Treatment of small slope and vertical surface
The die surface has high dimensional accuracy, high surface finish, small demoulding resistance and small demoulding slope. In order to achieve this purpose, the parts with small inclination of the workpiece are inserted separately, and the inserts are processed by wire cutting and grinding, as shown in the figure below.To ensure that the side wall is vertical, the running position or inclined top is required. There is an interface line at the running position. In order to avoid obvious interface, the wiring is generally placed at the junction of fillet and large surface.Treatment of small slope and vertical surface
To ensure that the side wall is vertical, the running position or inclined top is required. There is an interface line at the running position. In order to avoid obvious interface, the wiring is generally placed at the junction of fillet and large surface.Problems often to be solved for plastic parts1) Transition processing problem
The accuracy of plastic parts is generally not high. There must be transition treatment between adjacent parts and different surfaces of the same part.Small grooves are generally used for transition between different surfaces of the same part, and small grooves and high-low staggered surfaces can be used between different parts, as shown in the figure.Surface over treatment
2) Clearance value of plastic partsParts are directly assembled without movement, generally 0.1mm;The seam is generally 0.15mm;
The minimum clearance between parts without contact is 0.3mm, generally 0.5mm.3) The common forms and clearance of plastic parts are shown in the figureCommon forms and clearance taking method of stop of plastic parts

Nowadays, smart phones have changed from plastic back cover to thin metal body. Although the smart appearance attracts consumers, the production process of mobile phone case parts suppliers is more difficult. Only because the cutting and processing of the case requires quite high precision, even if it is only a small deviation, it may cause workpiece scrapping and erode profits.


In order to improve the yield of CNC processing, mobile phone box manufacturers are often forced to change tools frequently to ensure that CNC machines maintain a normal production beat, but this leads to an increase in the cost of consumables and also affects profits. In addition, the mobile phone case processing industry attaches great importance to the production rate, for fear that the sudden failure of CNC cutting machine will lead to negative chain reactions such as production capacity decline and delivery delay, which will damage customer satisfaction and goodwill. Therefore, it allocates manpower to carry out regular inspection and entrusts outsourcers to provide second-line maintenance support, but these methods are passive, It is difficult to effectively deal with abnormal conditions at the first time.
Mobile phone case is one of the cases of CNC machine application. CNC cutting is widely used in various processing and manufacturing, and various suppliers are facing a similar profit defense war. Xu Changyi, manager of Linghua technology measurement and automation products division, believes that whether you want to improve the machining accuracy or increase the productivity, the axe bottom salary drawing plan is to monitor the cutting process, especially the vibration monitoring, mainly because once the vibration value of the machine rises beyond the reasonable range due to imbalance, resonance or misalignment, It is easy to affect the operation of the machine, resulting in fault shutdown.
PC based monitoring solution is better than PLC solution to capture fine vibration signals
If the CNC processing machine can be endowed with intelligence and built with a set of full-time vibration monitoring mechanism, it can diagnose the health state of the machine at any time. Instead of waiting for the output of the final finished product and judging the cause of the abnormality afterwards, it can detect the unusual state of the processing machine in real time through preventive detection in advance and take corresponding treatment measures quickly, Including optimizing and adjusting processing parameters (such as changing spindle speed), or changing tools, etc. to solve small deviations immediately and avoid causing major disasters in the future.
It can not be denied that the cutting vibration monitoring of CNC machining machines is not a new topic at this moment. In the past, there were some PLC solutions with the demand of simplicity and convenience, which boasted that as long as the CNC machine was connected, it could produce utility quickly; Therefore, it is inevitable that some people wonder why PC based monitoring scheme is needed since PLC is available to assist in cutting vibration monitoring?
The so-called devil lies in the details. Some subtle vibration signals or high-frequency signals reflect some facts to some extent. It may be that the connecting mechanism begins to be unbalanced, the rotating spindle bearing ball breaks and affects the transmission power, or the fasteners become loose, which means that the CNC machining machine begins to "get sick", and the symptoms are different with the different machine characteristics; These subtle and changeable signs are not easy to capture by virtue of the PLC solution with the characteristics of low sampling rate, supporting limited bandwidth range and fixed algorithm. If the CNC monitoring solution can capture small changes and help users quickly grasp the key factors that may lead to reduced accuracy or capacity decline, they can respond as soon as possible.
In view of this, Linghua launched a cutting vibration monitoring scheme called mcm-100, which boasts that it can carry out 24-hour continuous data acquisition and vibration measurement for rotating transfer machinery and equipment under the condition of high precision and high sampling rate, and integrate the functions of data collection, vibration analysis and calculation, operation, Internet access and so on, Assist CNC machine users to successfully solve various challenges faced by traditional cutting process, and endow CNC machine with intelligence in the most relaxed and burden-free way.Achieve the wonderful effect of preventive maintenance through high-precision monitoring
Xu Changyi explained that generally speaking, there are three detection situations that CNC machines most want to establish. One is "spindle vibration detection", which aims to monitor the vibration of the spindle during cutting. The method is to directly measure the RMS value of the time domain signal. If it exceeds the critical value, reduce the speed or stop running; The second is "bearing quality diagnostic tic", which is intended to diagnose the health status of bearings. It is carried out when CNC does not perform cutting and only idles at high speed; The third is "spindle collision detection", which is used to detect the spindle collision. When the vibration wave pattern meets some default conditions, it is judged that the collision has occurred, and the spindle movement is stopped immediately.
The above situations 1 and 2 are closely related to the accuracy and bandwidth range of vibration signals. PLC solutions can capture very little information, which is difficult to help users establish contingency strategies; In contrast, mcm-100 not only has 24 bit high resolution capability (generally falling in the range of 12 or 16 bit), but also can capture high-frequency signals with a sampling rate of up to 128ks / S (generally only supporting 20Ks / s or even lower), so as to provide users with more vibration analysis materials.New business opportunities for CNC machine equipment manufacturers
On the other hand, the cutting vibration monitoring scheme can also create new business opportunities for CNC machine equipment manufacturers. As CNC machine equipment suppliers are exposed to a large amount of vibration information, once combined with big data analysis, they have a more thorough understanding of the correlation between signal changes and machine failures. CNC machine equipment suppliers can make good use of the accumulated knowledge assets, give birth to value-added services, and even adjust their business model from selling out equipment to selling machine operation hours, Establish long-term stable income. According to Linghua technology, the operator of PC based cutting vibration monitoring scheme, the vibration monitoring scheme has entered the landing stage and has been adopted by various well-known CNC tool machine manufacturers, and its demand has increased significantly in 2017, which shows that both CNC processors and CNC tool machine manufacturers have increasingly keen demand for CNC cutting vibration monitoring scheme.

If you are new to the world of CNC machines or want to get information on the latest happenings in the CNC industry then you definitely need to be a part of the CNC machining zone. You can use various methods to seek out like-minded people that have advice to offer or need advice and can stay connected to the world of CNC machines.
Different methods to stay in touch You can subscribe to newsletters if you are a member of any association related to the CNC industry. This will help you to get the latest news in your industry. With the advent of the Internet it is also possible to search for various websites that offer a forum for like-minded people to come together to exchange their views on each aspect of the CNC industry, be it on CNC lathes, CNC routers, CNC engravers, CNC cutters or even on accessories such as spindles, chucks, etc. Training methods, programming, upgrading and expert advice on niggling problems can also be discussed on a real-time basis.
Various modes of extracting information in the CNC machining zone In addition to participating in blogs and receiving online newsletters over the Internet, you can also watch videos of various CNC machines and their functions, such as the 4 or 5 axis CNC lathes, CNC pipe bending machines, etc. You can also download e-books from various websites that offer invaluable advice and tips on various types of CNC machines in great detail. Many online zones also offer vital links to other sites that could help in the procurement or maintenance of CNC machines.
Participate in online forums One of the best methods of gaining knowledge about your industry is to participate in online forums. You can post your queries or narrate specific problems related to your CNC machine and get responses from various quarters. This could help you to view various solutions and choose the one that suits your specific situation. As time goes by, you can also offer advice to fellow members and also enhance your name in the CNC industry as an expert.
Use the CNC machining zone to procure machines, material and manpower You can save a lot on manufacturing and recurring costs by using the CNC machining zone to procure the right types of CNC machines and raw materials to make your production much more cost-efficient. You can also look for talented workers in this zone that can help run your machine at peak efficiency. You can now locate molds, cast-iron, stainless steel or aluminum blocks, support blocks, controllers, motors, etc without any difficulty. You can also outsource certain aspects of your work if you do not have the required resources, thus helping you to complete your orders without indulging in heavy investments or failing to complete your work on time.
You are certain to benefit by entering the CNC machining zone since other members of your industry could willingly help you out of your cutting, milling or grinding problems. You will also be able to locate new suppliers, clients and meet new people that can help your business to attain a cutting edge in these tough and competitive times.