China Shenzhen Perfect Precision Product Co., Ltd. company news

What turning tools are required for machining different threads of precision parts In the process of precision parts processing, when high-speed steel turning tools are used to turn threads at low speed, if turning tools with back rake angle Yp equal to zero degrees are used, it is difficult to remove the chips, and it is difficult to turn the thread tooth surface smooth. Therefore, thread turning tools with a back rake angle of 5 °~15 ° can be used. However, when the turning tool has a back rake angle, the tooth profile angle is easy to change. At this time, the method of correcting the tool tip angle is used to compensate for the tooth profile angle error. The thread turning tool with back and front angle can cut smoothly, reduce chip buildup, and turn threads with low surface roughness. However, because the cutting edge does not pass through the axis of the workpiece, the thread profile (axial profile) to be cut is not a straight line, but a curve. This error can be ignored for threads with low requirements generally, but it has a great impact on the tooth profile angle. Especially for thread turning tools with large back and front angles, the tip angle must be corrected. When turning triangular threads, when the thread turning tool with 10 °~15 ° back rake angle is grinded, the tool tip angle shall be reduced by 40,~1 ° 40,. If the precision of the thread is required to be higher, the back and front angle should be smaller (0 °~5 °) to turn the correct tooth profile. It must be pointed out that the thread turning tool with large back rake angle will not only produce thread profile deformation, but also produce a large back force Fp when turning precision parts. This force tends to pull the turning tool towards the inside of the workpiece. If the gap between the slide plate lead screw and the nut is large, the phenomenon of "knife cutting" (broaching) will occur.

Five Matters Needing Attention in Tool Radius Compensation for Precision Parts Processing In the process of precision parts processing, it controls the path of the tool center. For convenience, the user always compiles the processing program according to the part contour. Therefore, in order to process the required part contour, the tool center must offset a tool radius value to the inner side of the part: when processing the outer contour, the tool center must offset a tool radius value to the outer side of the part. This CNC device can automatically generate the tool center path in real time according to the part contour and the preset offset parameters, which is called the tool radius compensation function. 1. The establishment and cancellation of radius compensation mode are only valid in C0 or C01 movement command mode. Of course, some systems now support C02 and C03 modes, but in order to prevent errors, it is better not to use C02 and C03 commands in radius compensation setting and cancellation segments. 2. To ensure the safety of tools and workpieces when tool compensation is created or canceled, C01 motion mode is usually used to create or cancel tool compensation. If the tool compensation is established or cancelled by using the C0 movement mode, the programming method of establishing the tool compensation first, then lowering and withdrawing the tool, and then canceling the tool compensation shall be adopted. 3. In order to facilitate coordinate calculation, tangent cut in method or normal cut in method is used to establish or cancel tool compensation when precision parts are processed. When it is inconvenient to cut in and out along the tangent line or normal direction of the workpiece contour, the arc auxiliary program segment can be added according to the situation. 4. In order to prevent the tool from over cutting during the process of establishing and canceling the radius compensation, the starting position and the ending position of the program section for establishing and canceling the tool radius compensation should be on the same side as the compensation direction. 5. In the tool compensation mode, it is generally not allowed to have more than two consecutive segments of non compensated planar motion commands, otherwise the tool will also have dangerous actions such as over cutting.

Six technological characteristics of machining plane of precision parts The plane on the part can be divided into parallel plane, vertical plane and inclined plane according to its position relationship with the reference plane. The connection surface between the plane and other surfaces is usually called the connection surface. Milling bevel for precision parts is divided into simple bevel and compound bevel. Milling plane has the following process characteristics: 1. It can use a variety of milling cutters to process different positions and types of planes. The geometric shape and geometric angle of the milling cutter are suitable for rough machining to finish machining of various precision planes. The utility model can be used for a variety of combined machining of connecting surfaces. 2. The power of the milling machine is large, and the end milling can be used for advanced and efficient machining such as power milling, high-speed milling, step milling, etc. 3. Milling machines have various forms, such as horizontal milling machine, vertical milling machine, gantry milling machine, universal tool milling machine, etc. They can process planes and connecting surfaces with different positions, dimensions and shape accuracy. 4. There are a variety of milling methods for precision parts,. For example, the plane can be processed by either cylindrical milling or end milling, and the joint surface can also be processed by both end milling and cylindrical milling. 5. Using the function of milling machine, the function of fixture and the form of milling cutter, complex planes such as compound inclined plane can be machined. 6. Various types of indexable face milling cutters have the advantages of convenient blade replacement, long service life and high plane milling efficiency.

Seven Factors Affecting Milling in Precision Parts Processing In the process of precision parts, milling, as a common form of processing, is mainly used in the process of plane processing. Compared with grinding, the effect of milling is higher. In the process of milling, it can reduce the machining difficulties caused by complex parts. In the process of industrial milling, due to the influence of machine tools and other factors, the milling accuracy is affected, and the standard quality of processing cannot be reached. But what factors will affect milling? 1. The influence of milling vibration on machining accuracy milling vibration is caused by intermittent cutting characteristics of milling, milling mode (down milling or up milling), rigidity of process system and other factors. Milling vibration directly affects milling accuracy. 2. The multi edge cutter cuts into the workpiece surface intermittently, and the cutting force changes constantly when the precision part is processed, which causes the periodic vibration of the process system. 3. During up milling, there is a sliding distance when the milling cutter cuts into the processing surface of the workpiece, which makes the cutter bar lift. After cutting into the processing surface, the cutter bar is pulled down, causing periodic milling vibration. 4. Milling machine vibration caused by clearance of spindle, workbench guide rail, transmission mechanism, etc. affects machining accuracy. 5. Milling vibration is caused by insufficient rigidity of the fixture of the milling machine. 6. Milling vibration is caused by the diameter or length of long milling cutter shank and large milling cutter. 7. Milling vibration is caused by insufficient rigidity of workpiece or improper positioning or clamping.

What are the commonly used fixtures for precision parts processing disk parts Precision parts are usually used to process small disk parts with three jaw self centering chucks for clamping workpieces. If the surface with location accuracy requirements cannot be processed during the installation of three jaw self centering chucks, usually after finishing the inner hole, the inner hole positioning installation mandrel or spring mandrel is used to process the outer circle or end face to ensure the location accuracy requirements. When processing large disk parts, because the three jaw self centering chucks are not so large in size, Therefore, the workpiece is often clamped with a four jaw single action chuck or a disc. 1. Spindle When the workpiece uses the machined hole as the positioning reference and can ensure the coaxiality requirements of the outer circle axis and the inner hole axis, the mandrel can be used for clamping. This clamping method can ensure the coaxiality of the inner and outer surfaces of the workpiece, and is suitable for certain batch production. There are many kinds of mandrels. The workpiece is usually positioned by a cylindrical hole with a circular mandrel and a small taper mandrel; For the positioning of workpieces with taper holes, threaded holes and spline holes, the corresponding taper mandrels, threaded mandrels and spline mandrels are commonly used. When positioning and clamping the taper mandrels or taper mandrels, pay attention to their contact with the workpieces. 2. Flower disc The disc is a large disc mounted on the lathe spindle. Precision parts with irregular shape can be used to process workpieces. For workpieces that cannot be clamped with three jaw self centering or four jaw single action chuck, they can be clamped with a disc. It is also a common fixture for machining large disc sleeve parts. There are thousands of T-shaped grooves on the disk, which are used to install positioning elements, clamping elements, indexing elements and other auxiliary elements. It can process the outer circle, end face and inner hole of disk sleeve parts or eccentric parts with complex shapes. When using the disc to clamp the precision parts to process the workpiece, pay attention to the balance, and use the balancing device to reduce the vibration generated by the high center and the wear of the main shaft bearing. Generally, there are two kinds of balancing measures: one is to add balancing weights (counterweights) on the heavier one, and the farther away from the high turning center, the better; the other is to machine the heavy hole on the heavier one, and the closer the position is to the turning center, the better. The position and weight of the balancing weights are best adjustable.

What are the ways to divide the turning milling composite processing procedures: The process of machining parts in Dongguan turning milling compound machining center can be relatively concentrated. In one clamping, most or all processes can be completed as far as possible. Generally, the process can be divided into the following ways: 1. The process shall be divided according to the clamping and positioning method of parts. Different parts have different structures and shapes, and the positioning methods during processing are also different. Generally, the internal shape is positioned when machining the profile, and the internal shape is positioned according to the profile. Therefore, processes can be divided according to different positioning methods. 2. The processes are divided according to rough and finish machining. When dividing processes according to the processing accuracy, stiffness, deformation and other factors of parts, the processes can be divided according to the principle of separating rough and finish machining, that is, rough machining first and then finish machining. 3. Process is divided according to the used basis. In order to reduce the number of tool changes, reduce the idle time, and reduce unnecessary position errors, parts can be processed according to the method of tool concentration process, that is, in one clamping, use the same tool as much as possible to process all parts that can be processed by turning and milling in Dongguan, and then use another tool to process other parts.

What are the steps to formulate the process specification of parts for turning milling composite processing The process procedure of turning milling compound machining parts is the processing method and step of parts. His content includes: arranging the processing procedures (including heat treatment procedures), determining the machine tool, clamping method, measurement method, machining allowance, cutting amount, and man hour quota used in each procedure, and filling in each content on a process card to guide the production and processing process. The steps to formulate the part process specification are as follows: 1. Process analysis of parts. 2. Selection of blanks. 3. Selection of positioning datum. 4. Formulation of process routes. 5. Select the manufacturing machine tool equipment. 6. Select manufacturing tools, fixtures, measuring tools and other auxiliary tools. 7. Determine the machining allowance, process size and tolerance of the process. 8. Determine the cutting parameters of the process. 9. Estimate time quota. 10. Fill in process documents. Process procedures are the main process documents that are determined by words, charts and other carriers to guide product processing and worker operation. It is the basic basis for enterprises to plan, organize and control production, and an important guarantee for Dongguan turning milling compound processing enterprises to ensure product quality and improve labor productivity.

How to Control and Avoid Milling Vibration in the Process of Precision Parts Processing In the process of precision parts processing, the vibration of milling will affect our processing accuracy. The vibration of milling is caused by the intermittent cutting characteristics of milling and the rigidity of the process system. If we want to control and avoid milling vibration, we need to do the following four things: 1. The process system with sufficient rigidity shall be selected as far as possible, such as sufficient machine power, rigid fixture, reasonable milling cutter structure size, reasonable clamping method, clamping force, etc. 2. Before the washing operation, the clearance of each part of the machine tool must be adjusted reasonably, and the unused feed direction must be locked during processing. 3. Select reasonable cutter cutting angle and milling amount. 4. Adopt advanced vibration reduction measures for precision parts processing.

Five Basic Methods for Controlling Over cutting and Under cutting in Milling of Precision Parts In the process of machining precision parts, over cutting and under cutting of metal cutting is one of the difficulties that must be controlled to improve machining accuracy. The basic method of controlling over cutting and under cutting in milling process must pay attention to the following five points: (1) Improve the rigidity of the process system, and avoid elastic deflection and pulling between milling cutter, fixture, machine tool and workpiece. (2) Control the appropriate and minimum milling allowance to avoid excessive allowance causing over cutting by pulling or under cutting by deflection, and avoid the comprehensive phenomenon that excessive allowance causes under cutting due to difficult cutting and over cutting after additional allowance. (3) Control the wear degree and service life of the milling cutter. When it is necessary to control the machining accuracy and the allowance is relatively small, the milling cutter at the initial stage of normal wear should be used. (4) In the process of milling, pay attention to exploring the working shape, rigidity, material removal, cutting parameter selection, milling method and other related laws, and use the most stable milling scheme for processing. (5) Attention shall be paid to the method of eliminating under cutting allowance after multiple cleaning at the original predetermined position to meet the requirements of geometric accuracy of milling. It is very important to carry out the correct control method in the milling process of precision parts, otherwise it will lead to the birth of a large number of defective products and waste a large number of materials. To ensure the processing quality, we must strictly follow these five basic methods to improve the processing quality.

What are the key points of fixture debugging verification and machining inspection in precision part machining (1) In the processing of precision parts, the scribing of workpieces can be completed by bench workers. Generally, it is necessary to make a template with the same shape as the wing. (2) When milling and aligning, the rotary table shall be aligned at a certain bisection position, and the bisection line of a wing shaped piece shall be parallel to the vertical and horizontal of the workbench by rotating the workpiece. As for the horizontal position of the milling cutter and the workpiece, the coarse milling adjustment is determined by adjusting the length of the profiling rod, and the fine milling adjustment is determined by the horizontal micro movement of the workbench. (3) The finish milling is separated, and the shape, position and roller contact pressure of the formed surface of the rough milling spare parts are used. (4) In the process of precision parts processing, attention shall be paid to the use of up milling, convex surface 1 shall be milled in from the large end of the wing, and concave surface 2 shall be milled in from the small end of the wing. (5) The profile curve shall be inspected with a special sample plate. (6) The position of the wing piece is usually inspected visually by scribing. (7) After the shape inspection of each wing shape piece is qualified, the bisection of the workpiece surface can be checked with the aid of the bisector calibration device to recheck the highest point of the convex surface, and the bisection error can be determined by the difference of the indicated values.