Category Archive CNC Technology

Four key points of CNC precision machining

In order to ensure the quality of precision CNC processing products, the following four key points should be followed in precision CNC processing:

  1. Datum first: that is, the datum plane shall be processed first. In the machining process of precision parts, the appearance as the positioning datum shall be processed first, so as to provide a precision datum for the processing of subsequent processes as soon as possible, so as to reduce the processing error.
  2. Division of processing technology: for the drawing size with high quality requirements for precision machining, multiple processing process routes shall be made, which can generally be divided into three stages: rough machining, semi finishing machining and finishing machining. Mainly to ensure the machining quality of mechanical parts; Conducive to the scientific application of equipment; Facilitate the arrangement of heat treatment process; And facilitate the discovery of blank defects.
  3. Face first and then hole: for precision CNC processing, for parts such as box, support and connecting rod, the plane shall be processed first and then the hole shall be processed. In this way, the plane can locate and process the hole, ensure the position accuracy of the plane and the hole, and bring convenience to the hole processing on the plane and ensure the processing quality.
  4. Finish grinding: the finishing of main surfaces, such as grinding, honing, finish grinding, rolling, etc., should be placed at the end of the process route. The general principle of formulating the process route of precision CNC machining and the formulation of the process specification of precision parts can be roughly divided into two links. The first is to draw up the process route of machining mechanical parts, and then determine the process size, equipment and process equipment, cutting specifications and man hour quota of each process.

The above is a personal understanding of the four key points that need to be followed in precision CNC processing.

ken. tang@chengcg.com

CNC machining surface treatment process!

In the field of precision CNC machining, surface treatment technology is needed for machined parts with high requirements for strength and toughness. Let’s take a look at the surface treatment process of CNC machining:

  1. In the hardware mold industry, the process polishing technology of mold accessories processed by CNC is a very important link, and it is also an important process in the process of workpiece processing. The machining surface treatment process of precision mechanical parts is very important in the machining process. It is worth reminding that the mold surface polishing treatment of precision parts is not only affected by the process and polishing equipment, but also affected by the specularity of part materials. This has not been paid enough attention in the current machining, which also shows that, The polishing process itself is affected by the material.
  2. Precision CNC machining. At present, the machining technology to improve the surface performance of precision parts is constantly innovated and upgraded, but the most widely used in precision CNC parts machining are mainly hardening film deposition, nitriding and carburizing technology. Because nitriding technology can obtain a high level of surface properties, and the process of nitriding technology is very consistent with the quenching process of steel in precision parts.
  3. Details of surface treatment. The nitriding temperature is very low, so there is no need for fierce cooling process after nitriding technology treatment, so the deformation of precision machined parts will be very small. Therefore, nitriding technology is also one of the early technologies used to strengthen surface properties in the processing of precision mechanical parts, and it is also widely used at present.

The above is about the surface treatment process of CNC machining.

ken. tang@chengcg.com

Steps of CNC precision machining

What is the order of CNC machining? For precision part processing, it must be based on the structure of the part, the condition of the blank, and the requirements of positioning and clamping. The key point is that the rigidity of the workpiece will not be damaged. There are the following points:

1、 The familiar understanding of precision parts processing technology can be divided into several points:

  1. How to handle the previous process will not affect the positioning and clamping of the next process. The middle cross section has a general fine part processing process.
  2. First stop the adding process of the inner cavity, and then stop the shape processing process.
  3. It is better to use the same positioning and clamping method or the same tool to stop the process, so as to reduce the number of repeated positioning, tool change and the number of moving pressing plates. Dongguan machining factory method.
  4. In multiple processes stopped in the same device, the process of damaging the workpiece stiffness shall be arranged first.

2、 The precision machining process of all parts can be completed by using the same tool sequence. Using other tools can successfully complete other parts. This can reduce the number of tool changes, shorten the dead time and reduce unnecessary positioning errors.

3、 Sorting method of processing parts: for parts with a large amount of processing content, according to their structural characteristics, the processing parts can be partially red, such as internal shape, shape, surface or plane. Common machining plane, locating surface and post machining hole; First deal with simple geometry, and then deal with complex geometry; Firstly, the parts with low precision shall be processed, and the parts with high precision shall be processed.

The above is the steps of precision CNC machining.

ken. tang@chengcg.com

Reasons affecting CNC machining accuracy

In the field of machining industry, what are the reasons for the influence of CNC machining accuracy? Let’s look at the following reasons:

  1. The first is the error of position influence: it usually refers to the change or deviation degree of the mutual position of the actual surface, axis or symmetrical surface of the machined part relative to its ideal position, such as perpendicularity, position, symmetry, etc.
  2. Machine tool error: the self error of the machine tool usually refers to the dead angle error. The main causes of position error are the machining error caused by the gap and elastic deformation caused by the transmission in the machining process of machine tool parts, and the position error caused by the friction force that the tool head needs to overcome in the machining process. In the open-loop system, the position accuracy is greatly affected, while in the closed-loop servo system, the position accuracy mainly depends on the displacement detection.
  3. Geometric error: machining accuracy error caused by geometric error of CNC machining. In the process of CNC machining, due to the influence of external factors such as external force and heat generated in machining, the geometric accuracy of machine tool is affected, and the geometric deformation of parts processed on machine tool will lead to geometric error. According to the research, there are two main reasons for the geometric error of NC machine tools: internal factors and external factors. The internal factors causing the geometric error of the machine tool refer to the geometric error caused by the factors of the machine tool itself, such as the levelness of the machine tool workbench, the levelness and straightness of the machine tool guide rail, the geometric accuracy of the machine tool and fixture, etc. External factors mainly refer to the geometric errors caused by the influence of external environment and thermal deformation in the machining process. For example, the geometric error caused by the thermal expansion and deformation of tools or parts in the cutting process will affect the machining accuracy of machine tools and parts.
  4. Cumulative error: from the long-term data analysis and actual operation of part processing, it can be seen that the machining accuracy error caused by the positioning of CNC machining machine tool. The positioning of machine tool has a great influence on the machining accuracy of NC machine tool. In terms of structure, the machining error of NC machine tool is mainly caused by positioning accuracy, and the feed system of machine tool is the main link affecting positioning accuracy. The feed system of NC machine tool is usually composed of mechanical transmission system and electrical control system. In the structural design, the positioning accuracy is related to the mechanical transmission system. In the closed-loop system, the CNC machine tool can usually prevent the position deviation of the main components in the feed system (such as ball screw and other components) through the positioning detection device. However, for the open-loop system, due to many influencing factors and complex conditions, it is impossible to carry out positioning monitoring, so the machining accuracy of NC machine tool is greatly affected.

The above explanation is the reason why Dongguan CNC machining accuracy is affected. I hope it will be helpful to you after reading it.

The following is our company’s website and email address. Please contact us if necessary.

ken. tang@chengcg.com

How to correct with cutting fluid in CNC machining

There are two kinds of cutting fluids for CNC machining of product parts: Oil-based cutting fluid and water-based cutting fluid. Precision parts processing is a kind of accessories widely used in automobile, communication, medical treatment, clocks, mobile phones, computers and other industries. Different from ordinary parts, precision parts are more precise and more suitable for some industries with high requirements for precision. Micropore processing less than 2 nm is called micropore. The pore size of some catalysts is usually described. Micropore processing is difficult, especially for micropores with a diameter of less than 1mm. However, many mechanical products have this microporous structure. CNC machining feed machining route refers to the turning tool from the tool setting point (or the fixed origin of the machine tool) starts to move until it returns to this point and ends the processing program, including the cutting path and non cutting empty stroke paths such as tool cut in and cut out. The cutting fluid used for CNC processing of product parts can be divided into cutting oil, emulsion, semi synthetic fluid and synthetic fluid, cutting oil, emulsion (sometimes referred to as soapy water) and synthetic fluid (commonly known as environment-friendly fluid), synthetic fluid may be commonly used, but little is known about how to select cutting fluid in the machining process. Let’s look at the advantages and disadvantages of each cutting fluid.

  1. Cutting oil for CNC machining of product parts. Very high physical lubrication B is suitable for low speed, less cutting allowance C surface finish and provides excellent service.
  2. CNC processing emulsion is used for product parts: advantages: multi metals have good safety and good lubricity. The advantages of this method are: good rust prevention, easy sewage treatment, disadvantages: increase the dosage; emulsify the sewage oil at the same time. The odor is not well controlled. The equipment is very dirty. The stability of hard water is very poor. The filtration is poor and the mixing is poor
  3. Semi synthetic liquid is used for CNC processing of product parts: advantages

1。 Cooling effect is better than emulsification effect.

2。 Better rust prevention

3。 Cleaner than emulsion.

4。 Better filtration performance

5。 More suitable for hard water and dirty oil. More suitable for hard water and dirty oil. The antibacterial effect is better than emulsion. Disadvantages:

1。 Blisters easily in soft water.

2。 Oil resistance is worse than synthetic liquid.

3。 At high concentrations, there may be a tendency to skin allergy

4。 Synthetic fluid used in CNC processing of product parts: advantages:

1。 Very clean.

2。 It doesn’t smell.

3。 Senior operator acceptance

4。 Low consumption (12-20 weeks)

5。 Excellent cooling performance. Figure 6. Completely refuse to spill oil. Low bubble 8. Long service life. Very good filtration / rapid sedimentation performance, disadvantages:

1。 Low physical lubrication

2。 Sewage treatment is difficult. A sticky residue, especially in hard water. Incompatible with emulsion. React with polycarbonate. It may damage the paint surface of the machine. Through the description of the cutting fluid used for CNC machining of the above various product parts, we can better understand them and be more clear about what kind of cutting fluid to choose.

ken. tang@chengcg.com

What tools are used for CNC processing aluminum

In the machining process of mechanical parts, the appropriate selection of cutting tools can be directly related to production efficiency and ultra-high machining cost! Therefore, it is also a skill in the machining industry to choose what materials to process and what tools to use. Let’s take a look at what kind of cutting tools are used for metal and aluminum processing?

Aluminum, also known as aluminum alloy in the machining industry, is one of the most common and important metal materials. In the mechanical equipment manufacturing industry, almost 60% of the mechanical equipment spare parts are processed with aluminum, especially in lithium battery equipment, laser equipment, non-standard automation equipment, optical industry and electronic technology. More than 80% of the spare parts of this equipment are replaced with aluminum. In machining aluminum is also the most contact!

For aluminum processing, many people may say that it is OK to use ordinary white steel tools. It is also applicable if the cost is not high, which is really good. However, our production efficiency can’t be improved. It’s easy to wear when processing with white steel tools, and the tools will often break, especially small ones. This is not cost-effective. The tool we want to say is not two edge or four edge. It is a three edge tool. Aluminum cutting has unique advantages. Compared with ordinary tools, it continuously improves the working efficiency, is not easy to wear and break, and the dimensional accuracy control is also guaranteed. In the machining industry, it is called aluminum special tool, which is the best choice for aluminum processing!

The above is a brief description of what kind of cutting tools are used for machining aluminum. Thank you for your attention!

ken. tang@chengcg.com

Machining accuracy of CNC computer gong

High quality comes from exquisite technology. In the machining industry, there are often high-precision machining of mechanical parts, which should be completed by selecting suitable machine tools and equipment. Let’s take a look at the machining accuracy of high-speed CNC computer gongs?

CNC computer gong is actually CNC machining center, which is an automatic machine tool controlled by program. The control system can logically process the program with control code or other symbolic instructions, decode it through the computer, so as to enable the machine tool to perform the specified action, and process the raw materials into semi-finished products or finished mechanical parts through tool cutting. CNC machining is completely controlled by computer and completed by process programming according to the drawing of mechanical parts. CNC machine tool itself has high precision. Generally, the spindle speed is 8000 / r.p.m, the spindle of high-speed machine can reach 10000-15000 / r.p.m, the part plane precision can reach 0.002-0.005mm, and the hole precision can be controlled between 0.003-0.005mm. In case of complex machining of mechanical parts, different process methods are selected to complete the machining accuracy.

The above is about the machining accuracy of CNC computer gongs. Thank you for sharing!

About CNC Turniing

ken. tang@chengcg.com

Method for removing side burr of CNC machining parts

In the process of machining precision mechanical parts, there are often burrs on the side of the parts to be removed. If they are not removed in time, the machining accuracy of the parts will be affected, and the side burr jaws will not be clamped, resulting in danger. There are many ways to remove the burr on the measuring surface of parts. Let’s see how to remove the burr on the side of precision mechanical parts

The choice of deburring tools will be different when machining precision mechanical parts with different materials. General aluminum processing can directly remove burrs with a sharp knife; Special chamfering machine can be selected for steel processing, and chamfering knife can also be used for deburring on the machine tool; The deburring of POM material is more convenient because the material has no hardness and can be completed with a special saw blade. Many precision parts have special requirements for deburring, and the surface of parts cannot be scratched, so special attention must be paid to deburring!

The above is how to remove the burr on the side of precision mechanical parts. Thank you for sharing!

ken. tang@chengcg.com