As mentioned before, the generation of burrs has not been well solved up to now. This problem is not discussed here, but some effective control methods and methods are proposed for the burr problem in production, that is, to prevent the cementation or deformation reinforcement of the cutting tool and to avoid the burr.
➀ reduce surface roughness of cutting tool rake face;
➁ increase cutting tool rake Angle;
➂ reducing cutting thickness;
➃ for proper heat treatment, reducing plastic deformation;
➄ stick performance good cutting fluid resistant;
➅ according to the plastic parts, appropriate adjustment of cutting speed.
Establishing an ultra-stable processing environment;
Adopt special processing method
1. 1. Reasonable product structure design
On the premise of meeting the requirements of product use, the product structure should be able to restrain or reduce the appearance of burrs. For example, the oil hole structure of the eq6100-2 engine crankshaft produced by dongfeng motor company used to be inclined oil hole. Before drilling the inclined oil hole, the spot-head spot-head is spot-loaded with a 9mm nose-in ball, so that the inclined bit can be drilled correctly and the deviation of the drill bit and the outlet of the oil hole can be avoided in the drilling process. However, at the outlet of the oil hole of the connecting rod shaft, the thin hole wall is too pointed, which is prone to burr and easy to crack when medium frequency quenching. After changing the outlet of the oil hole of the connecting rod's journal to the straight hole of 98mm, this problem was solved well, as shown in figure l.
1.2 emphasis on deburring process in process design
Since the burr appears in the process of metal cutting, the key to control burr is in the process of parts processing. During the process, the deburring process should be reasonably arranged and specific requirements should be made to facilitate the operation and inspection of the process. What kind of process design is more reasonable, there is not a unified standard, should be combined with the actual and decided. Some technologists in some enterprises have weak awareness of deburring. In the process design, the deburring process is not considered at all, and it is regarded as an optional process. In order to simplify the process, the deburring process is not arranged, which is obviously wrong. On the contrary, if too much deburring process is arranged in the process, it is neither economical nor reasonable.
According to relevant data, different processing methods have different effects on burr formation. In this way, when possible, some processing methods can be avoided, or easy to produce burr processing methods centralized arrangement, and then unified processing. Another point is that the workpiece should be treated effectively before heat treatment, so as to avoid difficult removal after heat treatment.
1.3 improved deburring method and adopted new deburring technology
The traditional deburring process is manual grinding wheel or manual grinding on grinder. Although these methods are simple and easy to operate, their effects are unsatisfactory and the operation is difficult to grasp. In recent years, some enterprises have made some improvements in the method of deburring and received good results. For example, dongfeng automobile co., ltd. made use of emery cloth wheel to finish the crankshaft oil mouth edge. The process is simple, the quality is good and the efficiency is high.
In the past few years, a new method for removing burrs by electrolysis was popular in the manufacturing industry. Deburring by electrolysis is carried out by using the principle of metal workpiece producing anode dissolution in electrolyte under the action of dc power supply. Since burrs are protruding on the surface of the workpiece and have the smallest gap with the cathode, the current density is the largest, and the electron line is highly concentrated, the burrs closest to the cathode will be dissolved first, until the burrs are completely corroded. The research shows that this method can remove the burr at the holes, deep holes, blind holes and cross holes. However, the promotion of this deburring process has yet to be solved.
1.4 design special tools and machine tools
In actual production, this situation is often encountered, some workpieces due to structural reasons, so deburring becomes a difficult problem. For example, the casting of the inner cavity of the box parts, the flanging of the annular groove on the surface of the inner hole, etc. It is very necessary to design special tools and machine tools, which can not only improve product quality, but also reduce labor intensity and improve productivity. This point abroad is done better, deburring of special tools, tools have been quite common. Some domestic attempts have been made in this regard, such as special design of drilling - chamfered compound cutting tool, tapping - chamfered compound cutting tool, special elbow scraper, but not popularized.
1.5 strengthen production management
A modern enterprise should not only attach importance to technological transformation and the application of advanced manufacturing technology, but also strengthen its internal production management so as to improve its efficiency. In addition to the foregoing, strict production management is also necessary to reduce or eliminate the effect of burrs on product quality. In the process of parts, the damage of collision and percussion will occur during the transportation, clamping and assembly of the workpiece, which will form burrs and leave hidden dangers to product quality. Only when the management is strengthened, the collision and percussion will be significantly reduced and the damaged and unqualified workpieces will be screened out. At the same time, it also avoids the artificial barbaric operations.