The latest development of bearing grinding: high efficiency grinding
the development direction of grinding technology today is ultra precision, high efficiency and super hard grinding tools. Some people say that ordinary grinding wheel 19 means that the maximum capacity is 190 seats! The development of has come to an end, and the technology formed over the past 100 years cannot change any new tricks. The general trend is to develop in the direction of superhard. This statement has some truth, but it is not completely correct
superhard grinding tools have their advantages, but there are also some limitations. For example, it puts forward strict requirements for the spindle speed and rigidity of machine tools. Not every machine tool can be equipped with CBN grinding wheels. For another example, the coolant of CBN grinding wheel cannot be ordinary coolant, and the grinding wheel dressing also needs a special diamond roller. It can be seen that ordinary grinding wheels still occupy an irreplaceable position in today's metal processing field
then, has the development of ordinary grinding wheels really run out of talent? As we all know, grinding wheel is composed of abrasive, binder and air hole. To develop a new grinding wheel, we can only start from these three aspects. In fact, the development potential of these three parts is still great, and the continuous progress of technology promotes people's understanding gradually. The fact that Saint Gobain has new products every year is a strong evidence
the following discusses the latest development of grinding technology for bearing processing from the perspectives of internal grinding and end grinding, combined with the newly developed products of Saint Gobain. Among them, the grinding performance and service life of the new generation NQ abrasive developed for high-speed grinding in cylindrical grinding are times higher than those of the original abrasive products; The new vortex manufacturing technology for face grinding can make the grinding wheel structure obtain greater porosity, which fully reflects the efficiency of grinding
internal grinding
internal high-speed grinding: NQ grinding wheel shows full efficiency
here, high-speed grinding is defined as the working linear speed of the grinding wheel is more than 63m/s, and the general speed is generally m/s. High speed has the following characteristics compared with ordinary speed: (3) electric light source industry (energy-saving lamp) 20%; ① The production efficiency can be increased by more than 1 time; ② It can reduce the surface roughness parameter value of the workpiece by%; ③ The service life of the grinding wheel can be increased by about 1 time; ④ The grinding force will be reduced by about 40%, and the machining accuracy will be improved accordingly
high speed grinding: development of new abrasives and application of NQ grinding wheel
Saint Gobain developed SG Abrasives 10 years ago, which have higher hardness than ordinary fused corundum abrasives, and because the abrasives are microcrystalline structure, they have many sharp cutting edges and good self sharpening. However, in high-speed internal grinding, the grinding force decreases due to high speed, and SG abrasive cannot decompose under the condition of low grinding force, that is to say, its advantage in self sharpening cannot be reflected
for this reason, Saint Gobain introduced a kind of abrasive NQ (northon quantum) in 2007, which overcomes the weakness that SG is not suitable for low grinding force and has obvious advantages in applications such as internal cylindrical grinding and gear grinding. Like SG, NQ abrasive itself belongs to ceramic sintered corundum. The only difference is the shape of abrasive particles - this unique shape can make it produce better self sharpening under small grinding force. When the abrasive is subjected to grinding force, its passivated part will decompose along the crystal surface, and new sharp edges will appear and participate in the cutting effect, and the effect of self sharpening will be reflected. Table 1 and table 2 show several application examples of NQ grinding wheel
through practice, compared with SG grinding wheel, the service life of NQ grinding wheel is increased by% and the grinding efficiency (feed) is increased by about 30%. At the same time, the grinding power can be reduced by 15%, further improving the accuracy of the workpiece. Moreover, whether ceramic or resin grinding wheels, NQ Abrasives can give full play to the advantages of low grinding force and high grinding efficiency of angstron company headquartered in Dayton, Ohio
centerless grinding
high efficiency end grinding: vortex grinding wheel helps
vortex technology is to make abrasive particles into abrasive groups according to the designed organizational structure, and then use these abrasive groups to make grinding wheels. This technology makes the air permeability of the grinding wheel better, and the size of the air hole can also be adjusted according to the actual application, so that the coolant can enter the grinding area more fully, so as to ensure that the feed rate during grinding is larger, and at the same time, it will not cause burns
finishing machining drawing
Table 3 lists the application examples of bearing inner ring end face grinding. The basic requirement of end grinding is to obtain the required thickness and tolerance of inner and outer rings, as well as the required parallelism and flatness, which will be used as the reference plane for subsequent processing. The results show that the grinding allowance of vortex wheel is increased from 0.4mm to 0.6mm, the wheel speed and workpiece passing speed remain unchanged, and the dressing interval is extended from 10000 pieces/repair to 14000 pieces/repair, with an increase of 40%
from the above examples, especially the uneven distribution, ordinary grinding wheels still have considerable development potential, the forward development of metal processing industry has never stopped, and the increasing grinding demand calls for new abrasive products to meet
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