In the actual field processing, the use of powerful milling TOOL HOLDER is very common, and it is used as the basic Tool Holder by many users. Today, Sheng Anbei is going to talk about some key points that are not usually mentioned. Selection and use of powerful milling tool shank 01. About clamping force It is difficult to answer the question of "how much kg · m clamping force is needed for low Zui". It is easy for users to fall into the misunderstanding of judging the quality of powerful toolholder according to the nominal holding force in the samples of various brands. In fact, it can not be simply said that a good toolholder has a large holding force. Take big dazhaohe powerful milling tool holder with clamping force of 300kg · m as an example. In practical use, the actual cutting torque of Φ 32 milling cutter is no more than 60kg · M. even considering the safety rate, 250kg · m is completely enough. However, in addition to the clamping force, the following points are more important! 02. The inner diameter has enough shrinkage In practical application, there are many occasions where the tool shank diameter is close to the lower tolerance limit and is used with the reducer sleeve. At this time, no matter how big the clamping force is, only when the gap between the inner wall of the handle and the reducing sleeve, and the gap between the reducing sleeve and the handle of the cutting tool is zero, can the clamping force be generated and the cutting tool be clamped. According to the calculation, if the inner wall of the toolholder does not have more than 0.1-0.12mm shrinkage, then the clamping force is difficult to reach the nominal value. 03. The inner wall has a groove to hold the oil film In the processing site, there will be impurities mixed with iron powder and oil. No matter how to wipe them, they can not be cleaned thoroughly. If there is no groove in the inner diameter, the oil film will easily make the tool slip in the handle, and the clamping force will be reduced to less than 1 / 2. The size of the groove is also very important, too small can not play the effect, too wide will make the tool handle damage, leading to problems in the use process. For example, for a tool handle with a clamping force of 300 kg · m, the handle of the cutting tool will bear 2 tons of pressure every 1 cm2. 04. Inner wall thickness In the past, the inner wall of the tool holder of the needle roller locking method is relatively thin, although the clamping force is relatively large, but the rigidity of the body is not good, so it is easy to drop the tool. Recently, the tool holder with the inner wall thickness of 10 mm has become the mainstream product, which not only ensures the clamping force, but also enhances the rigidity. Selection and use of powerful milling tool shank 05. Run out accuracy When improving the cutting parameters, it is easy to focus on the problem of clamping force. Generally, we all know that in the cutting conditions, the feed is the most important factor affecting the machining efficiency, but we often don't know that the feed is the runout accuracy. Moreover, when the tool vibrates, it is easy to think of the rigidity of the tool handle. But in fact, the vibration of part of the tool caused by the excessive jumping accuracy of the tool handle is also one of the important reasons. 06. Clamp the center and port There is a tendency to weaken the clamping force at the end of the powerful tool holder, especially when the straight bobbin jacket is used to clamp the small diameter tool. In order to solve this problem, we think that it is a better scheme to open an appropriate slit in the depth of the inner diameter of the toolholder. The slit can make the body part shrink evenly, increase the shrinkage, and improve the jumping accuracy. In other words, it is necessary to set a reasonable slit in the inner diameter of the powerful toolholder to improve the clamping force, the jumping accuracy and the clamping force at the end. 07. High durability According to Article 3, the overall pressure of 60Ton will be generated after tightening the nut. Long time use will cause wear on the surface of the needle roller. At this time, the life of the handle should be considered. The service life of powerful milling toolholders in the market is different. The service life of different brands varies from 1 to 5 times. Users need to have enough discrimination. After the accuracy deterioration, the tool holder will have a serious impact on the service life of machine tools and cutting tools. Some of the impact is not easy to detect, but it is very serious. It needs regular inspection and timely replacement. 08. Marks on the handle of cutting tools In order to verify the influence of the tool shank scar on the clamping force, we artificially added three scratches with a depth of about 0.04mm to the milling cutter shank diameter. The final test results show that the clamping force will be reduced to 1 / 2 ~ 1 / 5 of the nominal value. When the tool is often dropped, the first thing we think of is the clamping force of the tool holder. In fact, it is very important to confirm whether there are scratches on the tool holder. The above is about the introduction of the main hilts. Objectively speaking, today's hilt industry is still uneven. Sheng Anbei suggests that the majority of users must recognize the well-known brand when purchasing the hilt, so as to ensure the quality of the hilt.
