2020 – Page 66 – CNC Machining & Turning, Milling, Metal parts

How to improve CNC machining accuracy

The maintenance of CNC machining center is very important, not only related to the machining accuracy of workpiece, but also directly affects the machining efficiency of CNC machining center. The maintenance operation points are as follows:

1. Before processing, it is necessary to determine the processing technology, make clear the content of the process card, especially to determine the shape of the parts to be processed, and know the content of the next processing program.

2. The blank size should be measured before clamping, and the blank placement must be carefully checked to see if it is consistent with the programming.

3. After the rough machining of the blank is completed, maintenance should be carried out to determine whether the workpiece is correctly divided? Computer gong processing | Dongguan high-speed computer gong processing | Dongguan mold processing | Dongguan Mechanical parts processing | CNC processing whether there is dislocation loosening? Is the dimension from the processing part to the reference point meet the drawing requirements? After checking, the shape and scale of rough machining should be measured timely and accurately.

4. Semi finish machining or finish machining can only be carried out after rough machining and maintenance is completed. After CNC machining, the technician shall check the shape and size of the machining parts, mainly checking the vertical and inclined processing parts and the base point size marked on the measurement drawing,

When machining with CNC engraving and milling machine, try not to use the maximum cutting capacity of the cutting tool for processing. The cutting tool of each material will have a maximum cutting amount. because

Because this value is only a reference value for users, it can not exceed this value, so in actual operation, try to be less than this value and control it at the value

Two thirds of that would be ideal. In this way, the tool can be used for a long time, and the tool life will be longer.

In addition, CNC engraving and milling machine processing will be

It is divided into two parts: rough machining and finish machining. The first part of rough machining should be faster and better in overall speed and tool selection, and all surplus parts should be cut off as much as possible

In order to save time and improve work efficiency, finishing is to adjust the speed of CNC engraving and milling machine appropriately to ensure the fine processing of products.

And it is a kind of application technology constrained by its own economic strength. Computer gong processing, Dongguan high-speed computer gong processing, Dongguan mold processing, Dongguan Mechanical parts processing, CNC machining center selection, because the price is far more expensive than ordinary machine tools, so it is subject to more constraints, and whether the machine tool selection is reasonable or not is more prominent. Correct selection of machining center is the key to make good use of machining center and make it play an effective role.

The cutting tools and cutting conditions for CNC machining

For effective metal cutting, machining materials, cutting tools and cutting conditions are the three main factors. These determine the processing time, tool life and machining quality. Cutting conditions must be selected reasonably for economical and efficient processing methods.

The three elements of cutting conditions: cutting speed, feed and cutting depth directly cause damage. With the increase of cutting speed, the point temperature will rise, resulting in mechanical, chemical and thermal wear. If the cutting speed is increased by 20%, the tool life will be reduced by 1 / 2.

Back feed conditions and tool wear are kept to a minimum. But feeding behind, cutting temperature rise, wear. It is less than the effect of cutting speed. Cutting depth has no effect on cutting speed and feed, small cutting depth, but cutting material in hardened layer will also affect tool life.

According to the user’s processing material, hardness, cutting conditions, material selection, feed and cutting depth, the cutting speed is used.

Based on the selection of the most suitable process conditions, these factors are selected. Regular life and stable wear are the most ideal conditions.

However, in practice, the selection of tool life and tool wear, through machining size, surface quality, noise reduction, heat and so on. Under certain processing conditions, it is necessary to study according to the actual situation. Difficult to machine materials such as stainless steel, heat-resistant alloy, can use coolant or choose a good rigid blade.

Reasonable selection of cutting tools

1。 Rough rotation, should choose high strength, good durability knife, in order to meet the large car turning, feedback.

2。 The essence of automobile is to select high precision, durable and good cutting tools to ensure the machining accuracy.

3。 Reduce the conversion time and knife convenience, should try to use machine knife and machine clip blade.

Select fixture

1。 General fixture should be selected to clamp workpiece as much as possible, and special fixture should be avoided;

2。 The coincidence of parts positioning datum reduces the positioning error.

Determine the processing route

Machining path is the part of tool path and direction relative to each other in the process of exponential control.

1。 It should be able to meet the requirements of machining accuracy and surface roughness;

2。 Shorten the processing route as far as possible and reduce the idle travel time of the tool.

Machining route and allowance

Machining process specification

Machining process specification generally includes the following contents: process route of workpiece processing, specific content of each process and equipment and process equipment used, inspection items and inspection methods of workpiece, cutting amount, time quota, etc.

So in the process of machining, what are the steps to formulate the process specification? Let’s take a look at it

1) Calculate the annual production program and determine the type of production.

2) Analyze the part drawing and product assembly drawing, and analyze the process of parts.

3) Select the blank.

4) Draw up the process route.

5) Determine the machining allowance of each process, calculate the process size and tolerance.

6) Determine the equipment and tools, fixtures, measuring tools and auxiliary tools used in each process.

7) Determine cutting parameters and man hour quota.

8) Determine the technical requirements and inspection methods of each main process.

9) Fill in process documents.

In the process of working out the process, it is often necessary to adjust the contents that have been initially determined before in order to improve the economic benefits. Computer gong processing, Dongguan high-speed computer gong processing, Dongguan mold processing, Dongguan Mechanical parts processing, CNC processing, in the process of implementing the process specification, there may be unexpected situations, such as the change of production conditions, the introduction of new technology and new technology, the application of new materials and advanced equipment, which require timely revision and improvement of the process specification.

The technological process of machining includes, generally speaking, the process of changing the overall dimension and performance of the workpiece through a kind of mechanical equipment.

The working principle of machining process regulation is high quality, high yield and low cost, that is, under the premise of ensuring product quality, labor productivity can be improved and cost can be reduced as much as possible. What problems should be paid attention to in the process planning? Here’s a look:

1., the advanced technology.

In the formulation of machining process procedures, computer gong processing, Dongguan high-speed computer gong processing, Dongguan mold processing, Dongguan Mechanical parts processing, CNC processing should make full use of the existing production conditions of the enterprise, as far as possible, use domestic and foreign advanced technology and experience, and ensure good working conditions.

2. Economic rationality

Under the specified production program and production batch, there may be several process schemes that can meet the technical requirements of parts. At this time, the process cost is generally required to be the lowest through accounting or comparison with each other. Make full use of the existing production conditions, spend less and do more.

3. Good working conditions

High speed CNC machining

Computer gong processing after thousands of years of history of ups and downs, to now, all aspects have gradually matured and improved. In recent years, under the fierce competition at home and abroad, computer gong processing, Dongguan computer gong processing, Shenzhen computer gong processing, mechanical parts processing, Guangzhou computer gong processing, some small and medium-sized enterprises are facing various kinds of difficulties, struggling on the edge of life and death.

Change is the only way out.

Many hardware manufacturing enterprises have recognized this problem and began to make changes, but they often treat the symptoms rather than the root causes, ignoring the most important things. In order to find a way out, some enterprises began to learn the advanced western marketing methods, conduct in-depth research on the market, sell through the Internet, or change to service-oriented, and put forward the slogan of “customer is God, service is life”, or think “channel is king”, and think that the ultimate purpose of producing products is to sell them.

Some small and medium-sized hardware enterprises with low technology content and labor-intensive attribute their shortcomings to the lack of advanced machines. Computer gong processing, Dongguan computer gong processing, Shenzhen computer gong processing, mechanical parts processing, Guangzhou computer gong processing think that the reason why they can not be bigger and stronger is that they can not independently increase investment in science and technology due to the lack of funds and strength, so they can only cooperate with or be owned by large enterprises Finally, they lost themselves and gradually disappeared on the stage of hardware.

There is no doubt that these changes in technology and sales have been active and stimulated the traditional hardware products, making them glow with new vitality. However, most of these improvements are temporary and have changed vigorously for more than ten years. However, the dilemma faced by China’s hardware manufacturing industry has not been fundamentally changed. Most of the small and medium-sized hardware enterprises are still in the world market , can not get steady development.

If we stop to look at the manufacturing power – “Germany”, we will find that in fact, we are not too many small and medium-sized enterprises, but neglect the most basic thing – a heart that wants to make high-quality products. Dongguan Machinery parts processing when an enterprise to put a stable mind, no longer for profit and production, do not rely on low-cost labor, do not blindly invest money for equipment, machinery and technology is only icing on the cake, CNC processing brand and success is only a natural thing. German manufacturing industry is well-known in the world, and some small companies can also make big brands to be sought after in the world, mainly because they can focus on creating high-quality products.

The importance of bearing maintenance in CNC machining

First, clean the bearing in gasoline, wipe off the oil sludge and dust left on the bearing, and gently wipe and polish the rusty bearing with metallographic sandpaper until there is no roughness by hand.

2. Dry the cleaned bearings with dry rags, and then soak them in antirust oil. Computer gong processing, Dongguan high-speed computer gong processing, Dongguan mold processing, Dongguan machine parts processing, CNC processing, in this process, the bearing should be completely contacted with the antirust oil, and the bearing should not stop rotating, so that the oil film formed by the antirust oil can cover the surface of the bearing, so as to achieve the purpose of rust prevention.

3. Next, apply lithium grease and grease evenly on the surface of the bearing, including inner and outer rings, wheels and cages. And it is to wipe while rotating the bearing, so that the grease really into the bearing, play a full role in lubrication.

There are many ways to obtain the accuracy of measuring workpiece size in machining, one of which is the trial cutting method. What is its main operation?

That is, first try to cut a small part of the machined surface, measure the size obtained by trial cutting, adjust the cutting edge position of the cutting tool to the workpiece according to the processing requirements, computer gong processing, Dongguan high-speed computer gong processing, Dongguan mold processing, Dongguan Mechanical parts processing, CNC machining, and then cutting again, and then measuring. After two or three times of trial cutting and measurement, when the processed size meets the requirements, then cut the whole Surface to be machined. The trial cutting method is repeated until the required dimensional accuracy is achieved through “trial cutting – Measurement – adjustment – re cutting”. For example, trial boring of box hole system.

The precision of the trial cutting method may be very high, it does not need complex devices, but this method is time-consuming (need to make multiple adjustments, trial cutting, measurement, calculation), low efficiency, depends on the technical level of workers and the accuracy of measuring instruments, and the quality is unstable, so it is only used for single piece and small batch production.

As a type of trial cutting method matching, it is based on the processed parts, computer gong processing, Dongguan high-speed computer gong processing, Dongguan mold processing, Dongguan Mechanical parts processing, CNC processing and its matching another workpiece, or the method of combining two (or more) workpieces for processing. The final dimension to be processed in the matching process is based on the matching requirements of the machined parts.

History of metal manufacturing

Hardware manufacturing industry has a long history. Exploring the source of its development can almost keep pace with the history of China. Computer gong processing after thousands of years of history of ups and downs, to now, all aspects have gradually matured and improved. Dongguan high-speed computer gong processing, but China’s hardware enterprises are mainly small and medium-sized enterprises. In recent years, under the fierce competition at home and abroad, some small and medium-sized enterprises are facing various difficulties, struggling in the edge of life and death.

Change is the only way out.

Many hardware manufacturing enterprises have recognized this problem and began to make changes, but they often treat the symptoms rather than the root causes, ignoring the most important things. In order to find a way out, some enterprises began to learn the advanced western marketing methods and conduct in-depth research on the market, such as computer gong processing, Dongguan computer gong processing, Shenzhen computer gong processing, mechanical parts processing, Guangzhou computer gong processing, selling through the Internet, or changing to service-oriented, making the slogan “customer is God, service is life”, or thinking “channel” Tao is the king. “I think the ultimate goal of producing products is to sell them.

Some small and medium-sized hardware enterprises with low technology content and labor-intensive attribute their deficiencies to the lack of advanced machines. Dongguan mold processing thinks that the reason why they can’t be bigger and stronger is because of the lack of capital and strength, and they can not increase the investment in science and technology independently. They can only cooperate with a number of small enterprises or be absorbed by large enterprises to strengthen their strength. Finally, they lose themselves on the stage of hardware and gradually lose themselves Die out.

No doubt, these changes in technology and sales have stimulated the traditional hardware products, making them glow with new vitality. Computer gong processing, Dongguan computer gong processing, Shenzhen computer gong processing, mechanical parts processing, Guangzhou computer gong processing, but most of these improvements are temporary, and have changed vigorously for more than ten years, but the difficulties faced by China’s hardware manufacturing industry have never been solved Fundamentally changed, most of the small and medium-sized hardware enterprises are still in the world market, unable to get steady development.

If we stop to look at the manufacturing power – “Germany”, we will find that in fact, we are not too many small and medium-sized enterprises, but neglect the most basic thing – a heart that wants to make high-quality products. Dongguan Machinery parts processing when an enterprise to put a stable mind, no longer for profit and production, do not rely on low-cost labor, do not blindly invest money for equipment, machinery and technology is only icing on the cake, CNC processing brand and success is only a natural thing. Germany’s manufacturing industry is well-known in the world, and some small companies can also become big brands, thus being sought after by the world

CNC machining machine maintenance content

Maintenance contents:

1. Replace X-axis screw rod, screw nut, wire rail and bearing, adjust and repair the parallelism, twist degree, horizontal equal height of two line rails, manual scraping, screw rod and screw mother seat, and the comprehensive accuracy of bearing seat processed by Dongguan high-speed computer gong (parallel, equal height, center, twist, etc.) error is within 0.005 range. (remarks: one set of Haiwei ball screw, one set of Taiwan Haiwei linear guide rail, and six Japanese original nskp4 bearings).

2. Replacement of y-axis screw rod, screw nut, wire rail, bearing, adjustment and repair of the parallelism, twist, level and equal height of the two line rails, manual scraping, screw rod, screw mother seat, computer gong processing, Dongguan computer gong processing, Shenzhen computer gong processing, mechanical parts processing, Guangzhou computer gong processing

The comprehensive accuracy of the bearing pedestal (parallel, equal height, center, twist, etc.) error is in the range of 0.005. CNC processing (Note: Taiwan Haiwei ball screw set of 2500 yuan, Taiwan Haiwei linear guide rail set, Japanese original nskp4 level bearing 6).

3. Check and repair x, Y axis, mutual comprehensive accuracy, complementary accuracy, perpendicularity, displacement error (range 500mm ≤ 0.01mm)

4. Z axis precision adjustment, eliminate working clearance, vertical error 500mm ≤ 0.01mm, adjust the level of two line rails, Dongguan mold processing | twist degree, screw rod, screw nut adjustment, eliminate clearance, positioning accuracy, control within 0.005 range.

5. Unit maintenance, geometric accuracy, adjustment and repair, oil channel dredging, to make it meet the normal use standard. Positioning accuracy, linear interpolation, clockwise circular arc interpolation, screw interpolation, counter clockwise circular arc, spiral interpolation, cylindrical column difference compensation, etc. Dongguan machine parts processing system adjustment, mechanical adjustment, control panel, repair reset, replace the required accessories button, to achieve a clean appearance, flexible operation

The future of machining

(1) There are tens of thousands of old and backward machine tools in our country, which are the realistic basis of machine tool overhaul and CNC transformation industry

China is a developing country. Due to the long-term inadaptability of its own mechanism, the economic strength is too low, the technology is backward and the equipment is obsolete. The computer gong processing, Dongguan computer gong processing, Shenzhen computer gong processing, mechanical parts processing, Guangzhou computer gong processing have greatly restricted the development of the national economy. In order to change the backwardness of China’s machinery manufacturing industry as soon as possible, in the past 20 years, while developing the national machine tool manufacturing industry, we have actively introduced the world’s advanced technology and equipment. On the one hand, it cooperates with the world’s advanced machine tool manufacturers to continuously produce all kinds of machine tools with the world’s advanced level; on the other hand, it has directly purchased a large number of various types of machine tools. All these have played a huge role in the rapid development of China’s national economy. Dongguan computer gong Processing Factory Dongguan machine parts Processing Factory Dongguan mold processing factory Shenzhen computer gong processing.

However, the long-term operation of machine tools even overload use, and lack of serious repair and maintenance, resulting in serious wear and loss of precision; some machine tools are idle for a long time due to the change of enterprise personnel and product structure, or due to the lack of technical force, they are found to be rusty and the electronic control system can not be started up when they are used; due to the need of new product manufacturing, the machine tool has been seriously worn and lost its precision Due to the rapid development of computer and network technology in the world, the product update of CNC system and drive system factory is accelerated, and the original product is stopped prematurely, which brings some difficulties for the replacement and maintenance of spare parts. Moreover, the service life of CNC system is generally 5-10 years, while most of the machine tools in China are in the process of upgrading Extended service. Computer gongs processing, Dongguan computer gongs processing, Shenzhen computer gongs processing, mechanical parts processing, Guangzhou computer gongs processing, all of these factors need to be overhauled and CNC upgraded.

(2) A large number of new used machine tools have become the catalyst for machine tool overhaul and numerical control transformation industry. Since the reform and opening up, many enterprises have introduced a large number of obsolete machine tools from abroad. Although some of them can still meet the use requirements, most of them are still lack of experience, technology, data and spare parts, resulting in the embarrassment that although they are purchased cheaply, they can not continue to play a role The situation. Among them, there are many old machine tools and production lines introduced for use after transformation. Most of the second-hand machine tools here can play a role as long as they have appropriate capital investment, after overhaul and transformation, Dongguan computer gong processing factory, Dongguan machine parts processing factory, Dongguan mold processing factory, Shenzhen computer gong processing factory.

(3) Significant economic benefits are the driving force for the development of machine tool overhaul and numerical control transformation industry. For machine tool owners, they can get the same effect by spending less than 30% of the cost of purchasing the same new machine tool. According to the international records of the industry, even if the structural performance of the original machine tool is completely transformed and upgraded, it only costs about 60% of the price of the new machine tool.

Three elements of cutting conditions

According to the user’s processing material, hardness, cutting conditions, material selection, feed and cutting depth, the cutting speed is used.

Based on the selection of the most suitable process conditions, these factors are selected. Regular life and stable wear are the most ideal conditions.

Reasonable selection of cutting tools

1。 Rough rotation, should choose high strength, good durability knife, in order to meet the large car turning, feedback.

2。 The essence of automobile is to select high precision, durable and good cutting tools to ensure the machining accuracy.

3。 Reduce the conversion time and knife convenience, should try to use machine knife and machine clip blade.

Select fixture

1。 General fixture should be selected to clamp workpiece as much as possible, and special fixture should be avoided;

2。 The coincidence of parts positioning datum reduces the positioning error.

Determine the processing route

Machining path is the part of tool path and direction relative to each other in the process of exponential control.

1。 It should be able to meet the requirements of machining accuracy and surface roughness;

2。 Computer gong processing | Dongguan computer gong processing | Shenzhen computer gong processing | mechanical parts processing | Guangzhou computer gong processing

Shorten the processing route as far as possible and reduce the idle travel time of the tool.

Direction of foundry machine tool industry

Compared with the casting machine tool industry, computer gong processing, Dongguan high speed computer gong processing, Dongguan mold processing, Dongguan Mechanical parts processing, CNC processing, China’s casting machine tool industry is obviously backward in the production process level, which makes it has obvious deficiencies in the technical level and running speed of the core operating parts, the accuracy of the finished products and the reliability of the machine tools. It can be seen that the development of China’s foundry machine tool industry must start to actively seek new direction and concept.

Revolution becomes a new driving force in the field of casting machine tools

In order to meet the needs of industrial structure adjustment and low-carbon economy development and realize the scientific development of precision casting industry, the following work should be focused on:

1. To cultivate strategic emerging industries and modern production and service industries, so as to adapt to the transformation requirements of downstream areas, and provide support for the stable and rapid development of China’s equipment production industry. Dongguan CNC processing provides the basis for the establishment of modern casting industry system.

2. The network system of education and training in the field of precision casting has been constructed comprehensively. Various forms of school running can effectively cover the whole field of foundry education and training.

3. To help enterprises effectively use WTO and other international rules to deal with trade disputes such as anti-dumping and strive for the right of discourse in the international trade system.

4. Adhering to the principle of “go out, please come in”. On the basis of well running the high-level forum on China’s precision casting industry and the high-level forum on casting industry in mainland China, high-speed computer gongs processing in Dongguan, mold processing in Dongguan, mechanical parts processing in Dongguan, CNC processing, etc., will further improve the high-level forum of Asian casting industry and the high-level forum of BRICs casting industry, and actively participate in the world foundry industry Layer forum.

5. Substantive participation in international standardization work. During the 12th Five Year Plan period, several draft International Foundry specifications formulated by China will be submitted to the international standardization organization.

6. To carry out the National Foundry credit rating evaluation.