U drill: one of the most commonly used tools for hole machining!

Advantages of U drill:
1. First of all, the difference between U-drill and ordinary drill is that U-drill uses the peripheral blade and center blade of the blade. From this point of view, the relationship between U-drill and ordinary hard drill is actually similar to the relationship between machine-clamped turning tools and welding turning tools , the blade can be replaced directly without regrinding after the tool is worn. After all, using indexable inserts saves material over solid hard drills, and insert consistency makes it easier to control part size.
2. The rigidity of the U-drill is better, and a high feed rate can be used, and the processing diameter of the U-drill is much larger than that of the ordinary drill, and the maximum can reach D50~60mm. Of course, the U-drill cannot be used due to the characteristics of the insert is too small.
3. U drills only need to replace the blades of the same type and different brands when encountering various materials, and hard drills are not so convenient.
4. Compared with the hard drill, the accuracy of the hole drilled by the U drill is still higher, and the finish is better, especially when the cooling and lubrication are not smooth, and the U drill can correct the position accuracy of the hole, but it is not possible for the hard drill. Now, you can use the U-drill as an over-the-top rifle.
The advantages of U drill in CNC machining:
1. The U drill can drill holes on surfaces with an inclination angle less than 30~ without reducing cutting parameters.
2. After the cutting parameters of the U drill are reduced by 30%, intermittent cutting can be realized, such as machining intersecting holes, intersecting holes, and intersecting perforations.
3. The U drill can realize the drilling of multi-step holes, and can boring, chamfering and eccentric drilling.
4. Most of the drill chips are short chips during U-drill drilling, and the internal cooling system can be used for safe chip removal, without the need to clean the chips on the tool, which is beneficial to the processing continuity of the product, shortens the processing time, and improves the efficiency.
5. Under the condition of standard aspect ratio, there is no need to remove chips when using U-drill.
6. U-drill is an indexable tool, no need to sharpen after the blade is worn out, it is more convenient to replace, and the cost is low.
7. The surface roughness value of the hole processed by the U drill is small and the tolerance range is small, which can replace the work of part of the boring tool.
8. There is no need to pre-drill the center hole when using the U-drill, and the bottom surface of the processed blind hole is relatively straight, eliminating the need for a flat-bottom drill.
9. The use of U-drill technology can not only reduce the number of drilling tools, but also because the U-drill adopts the method of inserting carbide inserts on the head, and its cutting life is more than ten times that of ordinary drills. At the same time, there are four cutting edges on the insert. When the blade is worn, the cutting can be replaced at any time. The new cutting saves a lot of grinding and tool replacement time, and can increase the work efficiency by 6-7 times on average.
U-drilling skills on CNC machine tools
1. The rigidity of the machine tool and the alignment between the tool and the workpiece are highly required when the U-drill is used, so the U-drill is suitable for use on high-power, high-rigidity, and high-speed CNC machine tools.
2. When using a U drill, the central blade should be a blade with good toughness, and the peripheral blade should be a relatively sharp blade.
3. When machining different materials, inserts with different geometries should be used. In general, when the feed is small, the tolerance is small, and the aspect ratio of the U drill is large, the insert with a small cutting force is used. When the aspect ratio of the drill is small, a grooved insert with a larger cutting force is selected.
4. When using the U-drill, the spindle power of the machine tool, the clamping stability of the U-drill, the pressure and flow of the cutting fluid must be considered, and the chip removal effect of the U-drill must be well controlled, otherwise the surface roughness and size of the hole will be greatly affected. precision.
5. When clamping the U-drill, make sure that the center of the U-drill coincides with the center of the workpiece and is perpendicular to the surface of the workpiece.
6. When using a U drill, it is necessary to select appropriate cutting parameters according to different part materials.
7. During the test cutting of the U-drill, be careful not to reduce the feed rate or reduce the rotational speed at will, so that the U-drill blade is damaged or the U-drill is damaged.
8. When using a U drill, when the blade is worn or damaged, carefully analyze the cause and replace the blade with better toughness or wear resistance.
9. When using a U drill to process stepped holes, be sure to start with large holes first, and then process small holes.
10. When using the U drill, pay attention to the cutting fluid with sufficient pressure to flush out the chips.
11. The inserts used on the center and edge of the U-drill are different, and must not be used incorrectly, otherwise the U-drill shank will be damaged.
12. When drilling with a U-drill, workpiece rotation, tool rotation, and simultaneous tool and workpiece rotation are possible, but when the tool moves in a linear feed, the most common method is workpiece rotation.
13. The performance of the lathe should be considered when machining on the CNC lathe, and the cutting parameters should be adjusted appropriately, generally reducing the speed and low feed.
Common problems of U drill in CNC machining:
1. The blade is damaged too quickly, it is easy to break, and the processing cost increases.
2. There is a harsh whistling sound during processing, and the cutting state is abnormal.
3. The machine tool shakes, which affects the machining accuracy of the machine tool.
Points to note when using the U drill:
1. The installation of the U drill should pay attention to the positive and negative directions, which blade is up, which blade is down, which is facing inward and which is facing outward.
2. The center height of the U drill must be corrected. The control range is required according to its diameter. Generally, it is controlled within 0.1mm. The smaller the diameter of the U drill, the higher the center height requirement. The center height is not good for the two sides of the U drill It will wear out, the hole diameter will be too large, the service life of the blade will be shortened, and the small U drill will be easily broken.
3. The U-drill has high requirements on the coolant. It must be ensured that the coolant is ejected from the center of the U-drill. The pressure of the coolant should be as high as possible. The excess water outlet of the turret can be blocked to ensure its pressure.
4. The cutting parameters of the U drill are strictly in accordance with the manufacturer’s instructions, but also consider the blades of different brands, the power of the machine tool, and the load value of the machine tool can be adjusted appropriately during processing. Generally, high speed and low feed are used.
5. U-drill blades should be checked frequently and replaced in time. Different blades should not be installed backwards.
6. Adjust the feed amount according to the hardness of the workpiece and the length of the tool overhang. The harder the workpiece is, the larger the tool overhang is, and the smaller the cutting amount should be.
7. Do not use excessively worn blades. The relationship between blade wear and the number of workable workpieces should be recorded in production, and new blades should be replaced in time.
8. Use adequate and correct internal coolant pressure. The main function of the coolant is chip removal and cooling.
9.U drill cannot be used to process softer materials, such as red copper, soft aluminum, etc.