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

cnc four-axis machining in the process of processing will occur in many different situations, oil leakage is a frequent occurrence, to solve this problem, we must find out the root cause to solve things, for processing when the phenomenon of oil leakage is also seen, then which conditions will cause oil leakage? Oil change does not meet the requirements.   Cause cnc machining center oil leakage. The problems in oil change are mainly manifested in three aspects.   Oil change with too much oil, especially in the parts with rotating parts, due to the churning effect of rotating parts, more likely to appear oil overflow phenomenon.   For the parts with high viscosity lubricating oil, change the oil to low viscosity lubricating oil at will, it will make the corresponding box, shaft hole and other sealing performance is affected to a certain extent, sometimes will greatly reduce the sealing of these parts. When changing oil without cleaning the oil tank, the dirt in the oil tank may enter the lubrication system, blocking the oil path, wear seals caused by oil leakage.   The choice of lubrication system parts and adjustment is not appropriate and cause oil leakage:.   For example, cnc machining maintenance personnel maintenance selected too high pressure or too much oil out of the oil pump, or adjust the system pressure, relief valve, safety valve, pressure reducing valve and other pressure adjustment is too high, CNC machine tool lubrication system flow is too large, etc. with the oil return system and sealing system does not match, it will cause oil leakage.

The common types of wear in precision parts processing plant mainly include running wear, hard grain wear, surface fatigue wear, heat-like wear, phase change wear and hydrodynamic wear. Run-in wear is the wear of machinery under normal load, speed and lubrication conditions, this kind of wear is generally slow to develop, the short-term impact on the quality of processing is not significant.   Hard particle wear is due to the parts themselves dropped abrasive particles or hard particles from the outside into the machine tool, mixed into the processing area, subject to mechanical cutting or grinding, causing damage to the parts, which is more serious impact on the quality of processing.   Precision parts processing plant surface fatigue wear is machinery under the action of alternating load, resulting in tiny cracks or class point-like craters, thus causing damage to the parts. This type of wear is usually closely related to the pressure size, load characteristics, machine parts materials, size and other factors. Heat-like wear is the parts in the friction process generated by the heat on the parts, so that the parts have tempering softening, scorching creasing and other phenomena. This type of wear usually occurs in the high-speed and high-pressure sliding friction, wear is more destructive, and accompanied by the nature of accidental wear.   Corrosion wear is a chemical effect, that is, chemical corrosion caused by wear. When the surface of the parts and acid, alkali, salt liquid or harmful gas contact, it will be chemical erosion, or the surface of the parts and oxygen combined to generate easy to fall off the hard and brittle metal oxide and make parts wear.   Phase change wear is parts of long-term work at high temperatures, parts of the surface metal tissue grain heat becomes large, the grain boundaries around the oxidation, resulting in small gaps, so that parts fragile, wear resistance decreased, resulting in parts wear.

The common right-angle grooves in precision parts machining are open, closed and semi-closed, of which the tail of the semi-closed groove has two forms: vertical milling cutter arc (vertical arc) and disc-type milling cutter arc (lying arc). The keyway on the shaft is a typical right-angle groove with a flat key coupling the shaft and the sleeve, and the special-shaped grooves milled on the milling machine are V-groove, T-groove, semi-circular keyway and dovetail groove, etc. Machine tool guides, shaft parts are often positioned using V-grooves: T-grooves are mainly used to put on T-bolts, such as T-grooves on the machine table for putting on bolts to clamp the workpiece: dovetail fits are usually also used for machine tool guides, such as longitudinal and vertical guides for milling machines. Right-angle groove and special-shaped groove milling technology requirements (1) dimensional accuracy: the width, length and depth of the groove have certain dimensional accuracy requirements, especially for the parts that fit with other parts, the dimensional accuracy requirements are relatively high. Such as both sides of the keyway, because with the flat key, its width size tolerance is less than or equal to 0.052mm. (2) shape accuracy: various shapes of grooves after milling precision parts processing, should meet the shape accuracy requirements of the drawings. Right-angle groove and special-shaped groove are composed of plane, therefore, usually have the basic requirements of flatness and straightness. Used to fit the plane, its shape requirements are higher, such as the key slot on both sides of the surface, T-slot benchmark straight groove on both sides of the surface, V-slot V-shaped surface, dovetail groove with the bevel and horizontal surface. (3) positional accuracy: precision parts processing between the slot and the reference generally have positional accuracy requirements, such as the shaft key slot generally has a slot width size on the workpiece axis symmetry requirements, such as the T-slot middle plane and the reference side parallelism requirements, several T-slots between the parallelism requirements, in addition, the distribution of grooves on the shaft parts, there is equal precision or angle requirements. (4) surface roughness: the surface roughness requirements for each surface of the composition of the groove, the surface used to fit requires a small surface roughness value, such as the benchtop T-slot benchmark straight groove on both sides of the surface is often used for fixture positioning, therefore requires a small surface roughness value.

In the process of work, the problem of failure is very normal, so we should not be too surprised when we meet the failure, want to avoid more failures, then we have to do a good job of maintenance outside the work, many new users do not know what to do when they encounter failures, want to solve the problem, we must first find the source of the problem, the following together to understand the causes of large cnc machining is what? 1, may be the reason of the tool, sometimes it is not our operation what is wrong, but the problem of the accessories, because the tool is not sharp enough, not strong enough and so on these reasons will lead to the broken knife. 2、It is also because of the material problem, when the aluminum alloy shell is not uniform enough, uneven hardness and softness, or too many impurities will also lead to the occurrence of the problem. 3、The problem of clamping, we have to see whether the aluminum alloy shell is firmly clamped; whether the fixture is locked. These reasons are worth our attention. 4, there is the machine tool problem. CNC machining machine tool is level; voltage is stable; machine screw is aging and other such reasons   5, the preparation of the program, the preparation of aluminum alloy shell processing program, the spindle motor speed is too low; eating tool amount is too large; machining allowance is reasonable; aluminum chip discharge is smooth.

When turning slender shafts in the field of precision parts machining, the rigidity of the workpiece itself is poor, and if the center stand, the follow tool holder and other auxiliary tools are not properly adjusted, the geometry and surface quality will not meet the requirements, thus leading to bending. The workpiece has a large diameter and poor rigidity; the radial cutting force and centrifugal force during turning, the workpiece produces thermal deformation elongation and cutting stress; the blank material itself is a deformed rod and other reasons, which can cause the workpiece to bend.   The solution is to use the center frame, follow the tool holder, increase the rigidity of the workpiece; reasonable selection of the geometric angle of the tool (mainly large front angle, large main deviation angle), reduce the radial cutting force, reduce the generation of cutting heat; the use of spring top, reduce the adverse effects of the workpiece line expansion, fully pour cutting fluid, reduce friction and quickly take away the heat generated, the necessary heat treatment of the blank or workpiece. In the process of precision parts processing if the blank material itself or processing bending, should be timely straightening before continuing turning. Specifically according to the need to choose hot forging straightening, cold pressing correction, counterstrike method correction, counterstrike method straightening, pry hit straightening, simple tool straightening, quenching straightening, anti-torsional groove straightening and other appropriate methods.

Precision parts processing enterprises how to give product positioning, this issue, enterprises must pay great attention to. Each enterprise has its own goods, and each commodity has its own category, and positioning is to find this has the core competing ability goods, so as to enter this market, to obtain more customer orders. We are in an era of overproduction, CNC machining manufacturers are everywhere, the market economy is highly developed to provide customers with too many choices of precision parts processing. How to let customers choose their own, is the headache of every enterprise. The simple and brutal approach is to use the price to impress customers. So the more intense competition in the industry, the more inevitable the price war. You know, stable prices, will bring sustained profits, price war itself is unsustainable, with the price to attract customers will sooner or later leave you because of the price.   In addition to what you can sell cheaper than the competition, we have no other way, can make customers take the initiative to choose, and give you the right price? Of course there is, and that is differentiation. And positioning serves precisely to differentiate. Through positioning to find the weak point in the market, and the intersection of our own strengths, and then quickly cut into the new market, to establish their own corporate influence.   We often say to solve the customer's pain points, the reason why customers still have pain points, is because the existing product processing in this market can not fully meet their needs, especially in certain subdivision scenarios, subdivision of the field of demand. Such as precision parts processing of certain industries, aviation, cell phones, intelligent equipment industry, the need for more sophisticated equipment and testing equipment, not all CNC machining manufacturers can complete, we can complete the difficult, high-precision product manufacturing. These are from the point of view of the product, trying to find a business and competitors can play a differentiated positioning. Precision parts processing enterprises should always pay attention to the changes in the market, when the market changes have accumulated to a qualitative change, like the arrival of the Internet, that is, you should go to rethink the needs of buyers, re-adjust the positioning of the time. The success of the enterprise can not be separated from good positioning, of course, can not be separated from our own good competitive products.   Positioning theory should stand in the overall height and competition perspective, to see the development of an enterprise, is a strategic thinking for the market. Its role does not replace the product itself as the status of enterprise ballast. A correct view of positioning, flexible use of positioning, open new markets, we can get greater returns.

A. Tool position point cnc four-axis machining tool position point is a reference point on the tool, the tool position point relative movement of the track that is the processing route, also known as the programming track.   Second, the tooling and tooling point Tool setting is to make the tool position point coincide with the tool setting point by certain measurement means before starting the CNC program by the index control operator. You can use the tool setting instrument to the tool, its operation is relatively simple, the measurement data is also more accurate. You can also position the fixture and install the parts on the CNC machine tool after the use of measuring blocks, stoppers, micrometers, etc., using the coordinates on the CNC machine tool to the tool. On the operator, determine the point of tooling will be very important, will directly affect the accuracy of the machining of parts and program control. In the batch production process, it is more important to consider the repetition accuracy of the tool setting point, it is necessary for the operator to deepen the understanding of CNC equipment and master more tool setting skills. (1) the selection guidelines of the tool setting point   In the machine tool is easy to find the right, easy to view in the processing, easy to calculate when programming, and the tooling error is small. Tool setting point can pick a point on the part (such as the center of the positioning hole of the part), can also pick a point outside the part (such as a point on the fixture or machine tool), but must have a certain coordinate connection with the positioning reference of the part. Improve the accuracy and precision of tool setting, even if the part does not require high precision or the program requirements are not strict, the machining accuracy of the selected tool setting part should be higher than the machining accuracy of other orientations. Select the part with large contact surface, easy to monitor, and stable machining process as the tool setting point. Tooling point as far as possible and the design reference or process reference unified, to avoid the size of the conversion leads to tooling accuracy or even processing accuracy reduced, increasing the difficulty of CNC programs or parts CNC machining. In order to improve the machining accuracy of the part, the tooling point should be selected as far as possible in the design of the part benchmark or process benchmark. For example, the hole positioning parts, the center of the hole as the tooling point is more appropriate. The accuracy of the tooling point depends on both the accuracy of the CNC equipment, but also depends on the requirements of the parts processing, manual check the accuracy of the tooling to improve the quality of CNC machining of parts. Especially in the batch production to take into account the repetition accuracy of the tooling point, the accuracy of the tooling point can be used relative to the machine tool origin of the coordinate value to check. (2) the selection method of the tooling point On the CNC lathe or turning and milling machining center CNC equipment, due to the center of the orientation (X0, Y0, A0) has been determined by CNC equipment, determine the axial orientation can determine the entire processing coordinate system. Therefore, only need to determine the axial (Z0 or relative orientation) of a certain end face as a tool setting point can be.

Right-angle grooves in precision parts machining consist of three planes with a cross-sectional shape of three straight lines, with adjacent lines perpendicular to each other. Right-angle grooves are usually divided into three forms: closed, semi-closed and open right-angle grooves. Right-angle grooves can be distributed on flat and cylindrical surfaces. The more classical right-angle grooves are keyways, which are divided into ordinary flat keyways and semi-circular keyways. The characteristics of the milling process for right-angle grooves are as follows. 1. Using fixed diameter or fixed width milling cutters (such as keyway milling cutters, semicircular keyway milling cutters, disc-shaped slot milling cutters, etc.) to control the width of the slot size with high accuracy, such as keyway on the shaft with flat keys and semicircular keys, open right-angle grooves with matching accuracy requirements, etc.   2. The symmetrical position of the keyway on the shaft in the precision parts machining is usually different according to the accuracy level, respectively, using different tool setting methods. The keyway with high symmetry requirements uses the indicator table ring table method to find the relative position of the workpiece axis and tool axis or the middle section of the disc milling cutter, and the keyway with low symmetry requirements can be processed by the cut mark-to-to-tool method.   3. The machining of keyway on the shaft is usually done by V-block positioning or self-aligning chucking with indexing head to ensure the symmetry of the workpiece and other major machining accuracy requirements.

In the process of precision parts processing turning appeared zapping phenomenon The main reason for the phenomenon of zapping is: the workpiece clamping is not secure and walking, resulting in an increase in cutting volume. In addition, poor flexibility of the turning tool shank, the cutting dosage selection is too large, worm turning tool longitudinal front angle is too large, the cutting fluid is not properly selected or due to the cutting edge of the turning tool grinding dull and the emergence of hardening affects the cutting into, etc., may also cause a tool. Once the tool is tied, light damage to the tool, scrap the workpiece, heavy damage to the machine tool, it should try to prevent   Incorrect tooth shape in precision parts machining is mainly in the sharpening and installation of the turning tool. For example, the turning tool tip angle is not corrected; the turning tool tip and the workpiece center is not equal height; the tool tip angle bisector is not perpendicular to the axis of the workpiece; not according to the form of worm when finishing according to the requirements of the correct loading tool. In addition, the wear of the turning tool will also affect the correctness of the tooth shape. Poor surface quality Vibration caused by insufficient rigidity of the toolholder; dull or damaged turning tool; poor rigidity of the workpiece and improper selection of cutting amount; excessive borrowing amount during rough machining and cannot be corrected; insufficient margin in the finishing stage; improper selection of cutting fluid; chip tumor or chip pulling worm tooth side in turning will make the surface quality decline.

There are two series of indexable face mills for precision parts machining. Among them, the series of inserts with back angle is suitable for continuous milling of steel and cast iron parts, cutting lightly and effortlessly, consuming little power, requiring little process system, and a set of inserts with four cutting edges. The series of inserts without back angle are suitable for interrupted cutting of steel and cast iron parts, with high cutting edge strength, and are not easy to chip when processing hard steel and materials with uneven material. Using this type of milling cutter, the accuracy of the milling machine spindle is not high, but requires sufficient power of the machine tool, good rigidity of the process system, a set of inserts with 8 cutting edges, high utilization of the inserts.   According to the size of the main deflection angle, there are mainly two forms of 75° and 90°. According to the combination of back front foot (mainly affects the required cutting power) and side front (mainly affects the deformation and direction of chip discharge), it is usually divided into three forms. Double negative front angle type is suitable for rough milling and interrupted cutting; double positive front angle type is suitable for processing aluminum alloys, copper alloys, plastics and composite materials, as well as steel semi-finishing; negative, positive front angle type has the advantages of the first two combinations in, in Shanghai precision parts processing is suitable for processing a variety of carbon steel, alloy steel, tool steel, cast iron and stainless steel, etc., more versatile.