2020 – Page 92 – CNC Machining & Turning, Milling, Metal parts

The identification rule of coordinate direction for CNC machine tools

In order to simplify the way of programming for CNC machining and ensure the exchange of recorded data. The naming of the coordinates and targets of CNC machine tools has been formulated in the world for a long time. Jb3051-82 “naming of coordinates and targets of CNC machine tools” was formulated in 1982 in China.

In the CNC machining rules, the right-hand Cartesian coordinate system is selected to name the coordinate system of the machine tool. X, y and Z are used to represent the linear feed coordinate axis, and the relationship between X, y and Z coordinate axes is decided by the right skill:

The circular feed coordinate axis rotating around the X, y and Z axes is represented by a, B and C. according to the right-hand spiral rule, the targets of + A, + B and + C are confirmed, as shown in the figure.

Some of the feeding activities of CNC machine tools are completed by the spindle to start the cutter activities, some by the worktable with the workpiece activities. In normal programming, no matter whether the machine tool moves during machining or the workpiece is still moved, if the workpiece to be machined is relatively stationary, and the cutter is moving, and the object that the cutter is far away from the workpiece is the positive target Z axis of the coordinate coincides with the axis of the spindle, and the object that the cutter is far away from the workpiece is the positive target (+ Z); The x-axis is perpendicular to the Z-axis and parallel to the clamping surface of the workpiece. If it is a single column milling machine, the right moving target is the positive target (+ x) of the x-axis when facing the tool spindle to the column target; the y-axis can be confirmed according to the selected x-axis and z-axis according to the right technique..

How to improve precision machining?

Facing the penetration of high-tech such as artificial intelligence and big data into mechanical parts processing enterprises, the traditional precision mechanical parts processing plants are more distant. On the one hand, a large number of people are still not allowed to learn CNC parts processing and programming from scratch. On the other hand, these skills are brilliant, but it is difficult to land them. If a mechanical parts processing factory wants to invest in these skills, it may lose all its energy and cause the previous achievements to be wasted.

Now, precision machine parts processing plant is facing a big dilemma, that is, the profit margin is too low and the technology content is lower. The workshop of machine parts processing is still the traditional assembly line. In such a production mode, the new generation of employees are also defined as equipment and cost, and the subjective initiative cannot be developed. The old model is really out of date, and the new generation of employees are more and more disgusted with these mechanical work. Therefore, the automatic and intelligent machining of mechanical parts is highly sought after in order to completely free the hands of human beings. The manufacturing of some large products, such as automobiles and home appliances, is still basically automated. However, the manufacturing of Zhihao mobile phones, iPads and other products requires high precision. If the current automation equipment is unable to correctly install a soft cable, it is still necessary to ask for help In precision machine parts processing plant.

What should be paid attention to in the processing of non-standard fixture accessories

The following points should be paid attention to for grinding of non-standard fixture accessories:

1. Abrasive grain size for grinding shall be changed from coarse to fine in sequence. When changing abrasives, the grinding trace of the previous process should be completely removed. Grinding should be carried out until the grinding trace can only be seen this time. It is very important to prevent the “relief” phenomenon by punching the thimble.

2. The abrasive of the same size can only be used for the same grinding tool. Before changing the size, the workpiece must be completely cleaned to prevent coarse abrasive or other dirt from being brought to the next process to form scratch on the grinding surface.

3. Each time the next grain size is changed, the grinding shall be carried out at an angle of 30-45 ° with the last grinding target. If there are deep scars, it is not allowed to only grind the one-sided position, otherwise, the one-sided position will be pitted, and full trimming shall be carried out to remove the pit. It is necessary to pay attention to average grinding for simple grinding and not simple grinding stations

These are the articles shared today. Do you understand? If you want to know more about or need non-standard fixture accessories, please call our company or pay attention to our official website. We will sincerely serve you.

How to maintain CNC machine

The key point of prevention and maintenance of CNC machine tools is to strengthen daily maintenance, which includes daily inspection, weekly inspection, monthly inspection, quarterly inspection and semi annual inspection. CNC machining CNC machine tool prevention * * maintenance details are as follows:

1. Daily inspection of CNC machine tools

Its key items include hydraulic system, spindle smooth system, guide rail smooth system, cooling system and air pressure system. Daily inspection is based on the normal condition of each system. For example, when testing the process of the spindle smooth system, the power light should be on, and the oil pressure pump should operate normally. If the power light is not on, the spindle stop mode should be maintained, which is related to the mechanical engineer. Carry out repairs.

2. Weekly inspection of CNC machine tools

Its key items include machine parts and spindle smooth system, which should be inspected accurately every week. The unique thing is to eliminate iron chips and remove external sundries for machine parts.

3. Monthly inspection of CNC machine tools

If the main power supply and air dryer for inspection. Under normal conditions, the rated power supply voltage is 180v-220v, and the frequency is 50Hz. If there is any exception, measure and adjust it. The air dryer shall be disassembled once a month, and then washed and equipped.

4. Quarterly inspection of CNC machine tools

The quarterly inspection should focus on three aspects: machine bed, hydraulic system and spindle smooth system. For example, when inspecting the machine bed, it is important to see whether the accuracy and level of the machine meet the requirements of the manual. If there is any problem, it should be related to the mechanical engineer as soon as possible. When inspecting the hydraulic system and the spindle smooth system, if there is any problem, the new oil 6ol and 20L should be exchanged and washed.

5. Semi annual inspection of CNC machine tools

Half a year later, the hydraulic system, spindle smooth system and x-axis of the machine tool should be inspected. If there is any defect, the new oil should be replaced, and then the washing work should be carried out. After fully understanding and taking charge of the knowledge of prevention and protection, we must have a deeper understanding and necessary management of the causes and handling of the extra phenomena of the oil pressure system. For example, when the oil pump does not inject oil, the pressure is abnormal, there is noise and other phenomena, we should know what the key reasons are and what the corresponding treatment methods are.

The reason and treatment of the unusual phenomenon of oil pressure system should be understood from three aspects

(1) The key reasons for oil pump not to inject oil may include low liquid level in oil tank, reverse rotation of oil pump, insufficient rotation speed, high oil viscosity, low oil temperature, filter congestion, too large volume of oil suction pipe, air suction at oil inlet, damage of shaft and rotor, etc. there are corresponding treatment methods for key reasons, such as filling oil, confirming label, changing when oil pump reverses, etc.

(2) Abnormal pressure means high or low pressure. There are many reasons for this, such as improper pressure setting, bad coil behavior of pressure regulating valve, abnormal pressure gauge, leakage of oil pressure system, etc. The corresponding treatment methods include dismantling and washing according to the pressure configuration of the articles of association, replacing a normal pressure gauge, and checking in sequence according to each system, etc.

(3) Noise is mainly caused by oil pump and valve. When there is noise in the valve, the reason is that the flow exceeds the rated standard, so the flow shall be adjusted properly; when there is noise in the oil pump, there are many reasons and corresponding treatment methods, such as high oil viscosity and low oil temperature, the treatment method is to raise the oil temperature; when there is bubble in the oil, the air in the system shall be discharged, etc.