Monthly Archive September 14, 2020

CNC surface machining method

The machining method of CNC workpiece surface depends on the technical requirements of machined surface. However, it should be noted that these technical requirements are not necessarily the requirements specified in the part drawing, and sometimes they may be higher than the requirements on the part drawing due to process reasons. For example, because the datum does not coincide, the machining requirements of some CNC machining parts are raised. Or it may put forward higher processing requirements because it is used as a precision reference.

When the technical requirements of the surface of CNC machining parts are defined, the final processing method can be selected according to the requirements, and the processing methods of several steps and each step are determined. The selected CNC machining method should meet the requirements of parts quality, good processing economy and high production efficiency. Therefore, the following factors should be considered when selecting the processing method:

  1. There is a large range of machining accuracy and surface roughness that any CNC machining method can obtain, but only in a narrow range is economical, and the machining accuracy in this range is economic. Therefore, when selecting the processing method, we should choose the corresponding processing method which can obtain the economic machining accuracy.
  2. The properties of CNC machining parts should be considered.
  3. The structural shape and size of CNC machining parts should be considered.
  4. Productivity and economic requirements should be considered. In mass production, advanced technology with high efficiency should be adopted. Even can fundamentally change the manufacturing method of the blank, can reduce the amount of mechanical processing labor.
  5. The existing equipment and technical conditions of the factory or workshop should be considered. When selecting the processing method, the existing equipment should be fully utilized, the potential of the enterprise should be tapped, and the enthusiasm and creativity of the workers should be brought into play. However, it is also necessary to continuously improve the existing processing methods and equipment, adopt new technologies and improve the technological level

Advantages of CNC precision parts machining

This processing technology has been widely used in our industry. It is very common in our industry. The requirements of this processing technology are very high. Compared with the traditional process, it can achieve better results. There are many advantages that other processing methods do not have. What are the advantages of CNC precision parts processing?

  1. Multi axis control linkage: in general, three axis linkage is the most frequently used, but through some adjustment, four axis, five axis, seven axis and even more linkage axis machining center can be achieved.
  2. Parallel machine tool: the common machining center has a fixed function. The machining center and turning center, or vertical and horizontal machining center can be combined together, which can increase the processing range and processing capacity of the machining center
  3. Tool breakage warning: using some technical detection means, we can find the tool wear and damage in time, and give an alarm, so that the tool can be replaced in time to ensure the processing quality of parts.
  4. The management of the same cutting tool can improve the working efficiency of multiple cutting tools at the same time.
  5. Overload and power-off protection of machine tool: according to the maximum load level set according to the load in the production process, when the load reaches the set value, the machine tool can realize automatic power-off to protect the machine tool.

Price calculation of hardware parts processing

Many people will get some different prices when they go to the market for processing. Sometimes it is because of different prices, sometimes it is the same product, but in different businesses, they will get different prices. There are many influencing factors. So let’s learn how to calculate the price of hardware parts processing?

  1. First look at your drawings and technical requirements
  2. There are differences in materials and labor in different places, and there is a big price difference in some places
  3. General parts are calculated according to material cost + processing cost + profit. The processing cost depends on the process. The price of different processing equipment is of course different. Some are calculated according to working hours (turning time, grinding time, etc.), and some are calculated according to working procedures (such as how much is a folding plate for a knife, how much is a common drill hole, etc.)
  4. There is also a problem of quantity. A large quantity is certainly cheap. If it is a single piece, even if it is a small piece and the materials are not retailed, you should calculate the price of the whole board! For example, if you say 0.3, the manufacturer does not use it frequently. If you only buy one or two pieces of materials, if you only buy one board at a time (such as 1220 * 2440), you will be wrongly spent on the material cost.
  5. If the parts processing factory can solve the problems of the processing factory itself, of course, there is no problem. If the processing factory itself has some processes to be outsourced, the price will be correspondingly increased. If you are outsourcing, it means that you have been outsourced twice! So you should find the right one to find what they can do and what they are good at.

Precautions for CNC machining

In the process of processing, because we want to ensure the effect of the product, as well as our personal safety, so we need to pay attention to a lot of matters in the operation, such as some correct operation methods, these are basic, the correct operation method can avoid damaging the parts of the equipment, then we will learn what we should pay attention to in CNC processing What about the item?

(1) When the workpiece is too high, it should be roughened by different length of knife in layers. After using a big knife for roughening, the residual material should be removed with a small knife.

(2) The flat bottomed cutter is used to process the plane, and the ball cutter is used less so as to reduce the processing time; if there is a slope and it is an integer, it should be processed with a slope cutter.

(3) The reasonable setting of tolerance can balance the machining accuracy and the computer calculation time, do more procedures, and reduce the idle tool time.

(4) If the hardness of the blank material is high, the reverse milling is selected; if the hardness of the blank material is low, the down milling is selected. Rough machining up milling, finish machining down milling.

(5) The tool material has good toughness and low hardness, which is suitable for rough machining, while the tool material with poor toughness and high hardness is suitable for finish machining.

Advantages of CNC processing compared with 3D printing

Many people may not have too much understanding of these two, but in our industrial industry, the scope of application is still very wide. 3D printing and CNC machining are the more common production processes in the field of precision mechanical processing. They have similarities and differences. So let’s take a look at the advantages of CNC processing compared with 3D printing?

1、 Advantages of surface treatment

CNC machines provide better surface finish than 3D printing because the material does not deform during processing. Rigid materials and cutting actions keep the product together and there is less chance of error or deformation. The surface finish of 3D printing is poor. The material is bent, twisted or twisted because the material is laminated heated plastic.

2、 Prototype integrity improved

The numerical control machine tool does not heat the material and carries on the transformation. Materials remain stronger and have better structural integrity than 3D printers, and 3D printers must heat materials to build the desired product. 3D printers may also need to add foreign materials to the mixture to make prototypes, while CNC machines do not.

3、 Prototyping becomes easier

CNC machines are more suitable for prototypes that can withstand structural testing because they carve designs out of materials. They can also build prototypes using the exact materials that will be used to make the final product. Structural tests and changes will be more accurate because they use the same materials. This can speed up the production process, because the change will be design rather than material. 3D printers do not make prototypes with structural strength, so they cannot be physically tested.

4、 Price and volume do not represent price

The cost of 3D printing depends on the volume of material required. The final product quantity does not determine the price of CNC machine tools. For large orders, 3D printing is not cost-effective, which is the booming situation of CNC machine tools.

5、 The level of tolerance is rising

CNC machines are more accurate, so parts have better tolerances than 3D printers. Due to the tolerance level, prototypes with shafts or connections to other parts will have higher quality and are more likely to fit other parts.

6、 Quality benefits CNC

The larger layers of 3D printers are faster, but not as high-quality as smaller layers. If you need a prototype, you can choose to get it quickly but with a slightly lower quality, or wait longer to get the best quality prototype that the printer can provide. CNC machine tools allow you to choose the resolution of the items. They can provide different qualities in a short period of time, making them ideal for rapid build and instant test results.

7、 Cost reduction

If you can choose which manufacturing method to use for your product, CNC processing is usually cheaper than 3D printing.

Matters before CNC processing

We all know that no matter what work we are doing, we should do some preparatory work first, so as to ensure that our work can be carried out smoothly. Therefore, whether it is the preparatory work or to understand some common sense, these are very important. So let’s learn what we need to know before CNC processing?

CNC processing in Dongguan

  1. Datum first: that is to process the datum plane first. During the machining process of parts, the surface as the positioning datum should be processed first, so as to provide the precise datum for the subsequent processing as soon as possible.
  2. Distinguish the processing stage: precision CNC machining quality request high appearance, all distinguish the processing stage, generally can be divided into rough machining, semi finishing and finishing three stages. The first is to ensure the quality of processing; it is conducive to the scientific use of equipment; it is convenient to organize the heat treatment process; and it is convenient to find the defects of the blank.
  3. Face before hole: for parts such as box, bracket and connecting rod, the plane should be machined first and then the hole should be processed. In this way, the hole can be processed by plane positioning, which ensures the accuracy of plane and hole orientation, and brings convenience to the processing of holes on the plane.
  4. Finishing: the primary surface finishing, such as grinding, honing, finishing, rolling, etc., should be placed at the end of the process path. There are two parts in drawing up the general rules of fine CNC machining road and the drawing up of precision CNC machining procedure. The first is to draw up the process path of parts processing, and then determine the process scale of each process, the equipment and process equipment used, as well as the cutting standard, man hour quota, etc

Precautions for CNC machining of aluminum alloy

No matter what kind of work, there must be some matters to pay attention to in this process, so as to better ensure our work efficiency and product quality. Now aluminum alloy is widely used with high-precision instruments, so the requirements are higher and higher. At this time, whether it is manufacturing or processing, what matters should be paid attention to in CNC processing of aluminum alloy?

  1. The speed of white steel knife should not be too fast.
  2. When the workpiece is too high, please thicken it with a knife of different grade length.
  3. After roughening with a rough knife, remove the excess with the knife, and grind the knife after ensuring the excess.
  4. The plane is processed with flat bottom edge instead of ball edge to reduce processing time.
  5. The four corners of the calibration plane must be flat.
  6. The inclination is an integer, which is processed with an inclined cutter, such as tube position.
  7. Before each work, want to clear the remaining amount of the previous work after processing, to avoid empty tool and redundant processing.
  8. Try to take a simple path. For example, shape, trenching, avoiding single side, lapping, etc.
  9. When taking wcut, if you can go to finish, please don’t take rough.
  10. In the case of shape light knife, the light should be coarsened first and then exposed. When the workpiece is too high, it should be illuminated first and then.
  11. The tolerance should be set reasonably to balance the machining accuracy and computer calculation time. The tolerance is set to 1 / 5 of the remaining value when it is turned on, and 0.01 for a light knife.
  12. Add more projects to reduce the time of empty knife. Think more and reduce the chances of mistakes. Increase the auxiliary surface of the auxiliary line slightly to improve the processing condition.

Attention factors of CNC surface machining

If you want to do a good job, there must be many factors that need to be considered. It is very important for us to ensure the efficiency of work and the quality of products. But in the process of our work, there must be some factors that we can’t control, so this will lead to problems in the work, so let’s understand what factors should be paid attention to in the surface processing of CNC machining parts

  1. There is a large range of machining accuracy and surface roughness that any CNC machining method can obtain, but only in a narrow range is economical, and the machining accuracy in this range is economic. Therefore, when selecting the processing method, we should choose the corresponding processing method which can obtain the economic machining accuracy.
  2. The properties of CNC machining parts should be considered.
  3. The structural shape and size of CNC machining parts should be considered.
  4. Productivity and economic requirements should be considered. In mass production, advanced technology with high efficiency should be adopted. Even can fundamentally change the manufacturing method of the blank, can reduce the amount of mechanical processing labor.

Precautions of cutting fluid

In the process of hardware processing, we will use a lot of different things, because we want to do a good product is to pay attention to some details of the problem, so that we can make better quality products, so let’s learn about Dongguan Hardware processing using cutting fluid to pay attention to what matters?

(1) the cutting fluid shall be free from irritating smell and additives harmful to human body, so as to ensure the safety of users.

(2) the cutting fluid shall meet the requirements of equipment lubrication and protection management, that is, the cutting fluid shall not corrode the metal parts of the machine tool, damage the seal and paint of the machine tool, and shall not leave hard colloidal deposits on the guide rail of the machine tool, so as to ensure the safety and normal operation of the equipment

(3) the cutting fluid should ensure the anti rust oil effect between the working procedures of the workpiece and not rust the workpiece. When processing copper alloy, the cutting fluid containing sulfur should not be selected. The pH value of cutting fluid should be neutral when processing aluminum alloy.

(4) the cutting fluid should have excellent lubricating and cleaning properties. The cutting fluid with high Pb value and low surface tension is selected, and the cutting test shows that the cutting effect is good.

(5) The cutting fluid should have a long service life, and the machining center is particularly important.

(6) the cutting fluid should adapt to a variety of processing methods and workpiece materials.

(7) the cutting fluid should have low pollution and waste liquid treatment method.

(8) cutting fluid should be suitable in price and convenient in preparation. In conclusion, when selecting cutting fluid, users can select 2-3 kinds of cutting fluid with better comprehensive performance according to specific processing conditions. After trial use in the factory, the cutting fluid with proper performance can be determined

Precautions for machining!

In fact, no matter what is processed, there are matters needing attention, so as to ensure the quality of the products we produce. However, compared with large parts, processing is still relatively difficult, so there are many matters needing attention. So let’s learn about the matters needing attention in machining large parts?

  1. Large and medium-sized parts should be equipped with protective equipment before machining, and rubber gloves and necks are strictly prohibited. Before starting the CNC lathe, it is necessary to understand the main purpose and operation steps of each rocker, and check whether all positions of the CNC lathe are running normally. Before starting the CNC lathe, it is necessary to clamp the NC blade and steel parts with a wrench.
  2. It is forbidden to start the CNC lathe for machining large and medium-sized parts without the permission of the staff. It is not allowed to touch the running position in the process of speed regulation, chip removal or area measurement before starting. If dirt or cutting is found on the CNC lathe, it is forbidden to take it by hand or blow with mouth.
  3. During the machining of large and medium-sized parts, if it is found that the articles are loose or the machine equipment is abnormal, the car must be parked immediately. After the actual operation, the special tools should be removed and the working environment of the CNC lathe should be cleaned. It is not necessary to put the CNC blade, steel parts and other objects on the surface of the machine tool workbench.
  4. It is not allowed to touch the CNC blade, steel parts and its running components with hands in the machining of large and medium-sized parts. It is forbidden to lean the human body on the CNC lathe to prevent other safety accidents. When two people operate each equipment together, the division of responsibilities shall be established and close cooperation shall be established.
  5. About 40% of the gear transmission noise is caused by rough edges and bumps. Some processing plants remove the burr and bumps before the assembly line of the reducer, which is a common method to prepare the mechanism in advance. Special attention should be paid to the fact that in normalizing or heat treatment, the temperature in the furnace must be kept even, and the fixtures should be selected to make the steel parts evenly heated and cooled by water. It is forbidden to stack them together.
  6. Control the quality of raw materials: high quality raw materials are the necessary conditions for the production and manufacture of high-quality commodities. The raw materials used by enterprises, such as aluminum alloy profiles, Q235, stainless steel plates, 50Cr and 46 steel, are used to manufacture non-standard parts such as permanent magnet machinery and equipment, mechanical equipment and automatic machinery. No matter which way, the raw materials must go through rigorous composition detection, grain size measurement and purity identification after arriving at the plant. The aim is to adjust the deformation of quenching and tempering immediately and improve the quality of tooth profile production and processing. The enterprise has strict quality management process, including raw material review, production process management, commodity factory inspection, etc.