For machining, taps and drill bits are often encountered in the workpiece. The following solutions are available for reference. Solve the tap and the method of breaking the drill bit into the workpiece:
1. Fill the lubricant with a sharp tweezers or tweezers and slowly knock it out in the reverse direction of the fracture surface. The most common method, but it may not be suitable for threaded holes with too small apertures or broken taps that are too long, but try).
2. Weld a handle or hex nut on the broken section of the tap and then gently reverse it. (This is a good method, but the welding is somewhat troublesome, or the same is true for smaller diameter taps. )).
3, with a special tool: broken tap extractor, the principle is that the workpiece and the tap are connected to the positive and negative electrodes, the middle of the electrolyte, causing the workpiece to discharge corrosion to the tap, then the auxiliary needle nose pliers, etc., the inner hole The damage is small.
4. Take the top of the steel roller and tap it slowly with a small hammer at the tap of the tap. The tap is relatively brittle, and finally knock it out into the slag, or it is simpler. The threaded hole of the broken tap is directly smashed and re-reamed. Tapping (the method is somewhat savage, if the diameter of the tap is too small, it is not good, the diameter is too big, and it is very tiring to knock).
5. Flatten the threaded hole where the broken tap is located, and then flatten it and re-drill. Although it is difficult, it can be drilled slowly (if the threaded hole can be changed position, re-drilling and tapping) It is recommended to change to the original threaded hole).
6. Cut a slot on the cross section of the broken tap and reverse it with a screwdriver (the slot is difficult to cut out, it is even harder if the diameter of the tap is small).
7. Drill the threaded hole of the broken tap and then inlay a wire screw or pin, then weld, smooth, re-drill and tap, which can be basically the same (this method is troublesome, But very practical, the size of the tap does not matter).
8. Use electric pulse to knock off, EDM or wire cutting can be done, the hole can be reamed and the wire screw sleeve is added. (This method is simpler and more convenient. As for the coaxiality, do not consider it for the time being, unless your The threaded hole coaxiality directly affects the quality of the equipment).
9. Make a simple tool and insert it into the flute of the broken taper section. Carefully pull it back. For example, you can use the broken nut with a square twist to screw 2 nuts and use the wire (the number of The number of taps is the same. Insert the broken tap and the nut into the empty groove, then use the hinge to pull the square in the direction of the exit and take out the broken tap. The main idea of this method is to pass through the flute of the broken tap. It is better to use a steel needle as a wrench to take the broken wire. Of course, if such a broken wire often occurs in the workshop, it is better to make such a tool wrench.
10. The nitric acid solution can corrode high-speed steel cones and does not scrap the workpiece.
11. Anneal the tap with an acetylene flame or a blowtorch, and then drill with a drill bit. At this time, the diameter of the drill should be smaller than the diameter of the bottom hole, and the drill hole should be aligned with the center to prevent the thread from being drilled. Insert a flat or square punch and use a wrench to unscrew the tap.
12, reverse with the gas drill, relying on the feel, because instead of directly drilling the tap, but with a slow speed and a little friction (similar to the car half-clutch) let the tap follow.
13. You can use a grinder to smooth the broken wire, then drill with a small drill bit, and then gradually change to a larger drill bit. The broken wire will gradually fall off. After falling off, use the original tap to re-attack. Tooth, this advantage does not require an increase in the aperture.
14. Weld an iron rod on the broken object and then unscrew it. (Disadvantages: a, too small broken material can not be welded; b, the welding skill is extremely high, easy to burn the workpiece; c, the weld is easy to break, the probability of being able to take out the broken object is very small.)
15. Use a tapered tool that is harder than the broken object. (Disadvantages: a, only suitable for brittle fractures, break the broken material, and then slowly remove it; b, the broken material is too deep, too small to be taken out; c, easy to destroy the original hole.) Directly use an electrode that is smaller than the broken object and use an electric spark machine. (Disadvantages: a, useless for large workpieces, can not be placed in the EDM machine table; b, time-consuming; c, too deep, easy to deposit carbon, can not fight.)
18, with alloy drills (disadvantages : a, easy to destroy the original hole; b, useless for hard breakage; c, alloy drill bit is brittle and easy to break.)
19, now there is a portable machine tool designed and manufactured by electric machining principle, can Remove the broken screw and broken tap drill easily and quickly.
20, if the screw is not too hard, you can flatten the end face, then find the center point, use a small bit to go up, drill with a small bit, vertical, and then take out the broken wire The reverse can be screwed out.
21. If you can't buy the broken wire extractor, use a larger bit to continue to ream the hole. When the hole is close to the screw, some of the wire will not fall off, remove the remaining wire, and then re-use the tap. Finishing is fine.
22. If the broken wire of the screw is exposed, or the requirements for the broken screw are not strict, there is a saw with a hand saw, the saw can be sewn, and the outer casing is also sawed, and then removed with a flat-blade screwdriver.
23. If the broken wire is exposed to a certain length outside, and the melting point of the mechanical material is not too low, an elongated T-bar can be welded on the screw by electric welding, so that the welded rod can be easily unscrewed.
24, if the screw rust is very serious, using the above method is not easy to handle, it is recommended to use a fire to bake red and then add a little lubricant, and then use the above corresponding method.
25, after N efforts, although the screw is taken out, but the hole is also abolished, simply drill a larger hole tapping, if the original screw position and size are limited, you can also Hit a larger screw, or directly weld the tapping wire, and drill a small hole in the center of the large screw. However, internal metal structure problems after soldering are sometimes difficult to tap.