Efficient grinding technology is a necessary condition for advanced manufacturing technology , completely solve the traditional precision grinding , inefficient processing limitations in obtaining high efficiency, high precision , while a variety of materials and shapes can be abrasive fibre disc high surface integrity and reduce processing costs . Under China's current conditions , strengthen the research, promotion and application of efficient grinding technology, the level of China's machinery manufacturing industry to improve processing and accelerate new product development has great significance . Today, the increasingly widespread use of superhard materials , implementation of high-speed and efficient processing of superhard materials and grinding is the preferred process difficult to cut materials. Since the development of superhard abrasive applications, high-speed, high- precision machine tools and CNC technology development , new grinding wheel dressing and other fluids and related technologies , high-speed ultra-high speed grinding technology and high efficiency grinding , grinding, automation and development of intelligent technologies make high efficiency abrasive machining in machinery manufacturing field has a more important role , with good prospects for development. Efficient grinding wheel should have a good wear resistance, high precision balancing , crack resistance , good damping properties, high stiffness and good heat resistance, mechanical strength and be able abrasive paper sheet to withstand high cutting force during grinding and so on. Efficient grinding wheel can be used corundum, silicon carbide , CBN, diamond abrasive . Under suitable binding agent and the conditions of advanced manufacturing technology , production speeds of up to use abrasive 125m / s.
Existing vitrified wheel water, oil, acid, alkali corrosion , to maintain the correct geometry. Porosity big , grinding rate, greater strength , toughness, flexibility, vibration resistance is poor, can not withstand lateral forces , V wheel <35m / s grinding , this combination agent most widely used, can be made into a variety of abrasive for shaping existing strength resin bonded grinding and grinding threads, gears, crankshafts and other large and elastic , not afraid of the impact that can work at high speed . Friction polishing effect, but strong resistance and heat resistance than vitrified poor, not acid , alkali, porosity is small, easy to plug ; V wheel > 50m / s high-speed grinding , grinding wheel can be made thin slot edge grinding tool rake face , high-precision grinding. High strength inorganic polymer bonded abrasives , and therefore have a higher usage rate generally applicable to high-speed cutting, grinding shortage , heavy duty grinding ; addition of inorganic polymer binder mill has a certain elasticity , heat and binders high , grinding self-sharpening , so compared with traditional resin binder wheel corners to maintain good , good shape retention , but also for grinding, such as thread grinding , molding grinding, sharpening ; can say inorganic polymer binder having both ceramic abrasive performance, but also a resin having abrasive properties , while avoiding their drawbacks.
Inorganic polymer binder abrasives , grinding theory is based on basic and applied research, the concept is introduced into the abrasive composites production , the following aside inorganic polymer binders basic principles of physical chemistry (1 crystal chemistry of inorganic polymer material 2 . inorganic polymer materials thermodynamics 3 . process kinetics of inorganic polymer materials ) and to introduce the interface and toughening mechanism of composite materials , inorganic polymer binder specific about the new , efficient, dedicated , heavy-duty strength and precision abrasive production applications. While this advanced technology has gradually mastered the industry for a number of tools , but there are still a number of specific issues have yet to be conscientiously sum up experiences , study and solve . Here is the specific design principles and methods of inorganic polymer binder abrasive production , production of inorganic polymer composite high-speed heavy-duty grinding , abrasive grinding shortage , strong abrasive grinding , high efficiency deep grinding , creep feed grinding cutting abrasive, abrasive grinding quick points , efficient grinding abrasive, abrasive spindle and bearings , high efficiency grinding machine grinding , rail grinding abrasive, abrasive belt grinding process for mentioning some opinions . An inorganic polymer bonded abrasives design principles and methods
In the design and manufacture of the grinding wheel should consider the following questions: First, consider the performance of precision materials processing and materials processing surface , and then select the appropriate abrasive , abrasive grinding grain size and mixed use . Followed by a variety of stress conditions , impact resistance , speed, temperature , processing materials and abrasive grinding wheel life working conditions zirconia flap disc and choose a suitable binders , accessories , etc., and consider matching and scientific process between each other. Abrasive bond strength depends on the performance of the manufacturing process and abrasive grinding specifications. Considering factors that affect abrasive strength are: abrasive types , size, type and performance bond , abrasive hardness, organization , density, mixing, molding and curing conditions , abrasive shape , abrasive wheel outside diameter aperture the ratio . Wherein after the abrasive characteristics and specifications given , the most important binding agent performance, mixing and curing process molding process conditions . Another grinding wheel is also an important parameter ratio . Above factors involved , here we come eleven talk :
Combination of abrasive abrasive substrate and the extent and thickness of abrasive particle size distribution
Abrasive degree of thickness - is the size of the abrasive type , the degree of the overall thickness of the mix ; particle size distribution refers to a combination of different types , sizes, and quantity ratio or with abrasive conditions . Is an important factor from the abrasive grinding action of the abrasive , the abrasive nature of the workpiece according to the choice of the main materials, such as hardness, tensile strength , toughness, etc. to determine the selected abrasive basic principle is : high grinding the material hardness of the workpiece , you should choose a higher hardness abrasive ; grinding high tensile strength of the workpiece material should be used in large toughness abrasive ; grinding low tensile strength of the material should be used more brittle or high- strength silicon carbide abrasive. Various abrasive properties, uses and options, the choice here is not as elaborate abrasive particle size , should mainly be based on precision, surface roughness and grinding efficiency requirements to choose. General principles are as follows : grind the workpiece roughness requirements are high , you should choose a coarse-grained ; requires low surface roughness , fine-grained should be selected . When the work requires a higher geometric precision and low surface roughness , grain size should be selected mix . High precision workpiece geometry , when the abrasive wheel and the workpiece contact area hours should choose fine-grained ; large contact area , choose a coarse-grained . Workpiece material is hard and brittle , you should choose a fine-grained ; workpiece material soft and tough , you should choose a coarse-grained . Poor thermal conductivity of the workpiece , easy to heat deformation, easy to burn, should be selected coarse granularity. These problems are related to the factors that affect the performance of abrasive grinding thermal conductivity , heat capacity , density, porosity and other abrasive usually divided - coarse abrasive, abrasive , abrasive powder fine abrasive and so are several . Under the same conditions with an abrasive , abrasive powder larger total surface area , total surface area of less coarse abrasive . Abrasive surface required in the production of tuberculosis agents parcels, giving bond strength, the greater the total surface area of the abrasive child , you need to wrap the abrasive surface of the inorganic polymer binders will get. Generally with coarse abrasive than the fine abrasive inorganic polymer used in small doses combined . Abrasive particle size distribution, in order to make the grinding efficiency, not only to consider the strength and machining abrasive materials , but also must determine what kinds of abrasives with the amount of grading that is abrasive . When conducting abrasive grinding , abrasive grinding body on the one hand the role of impact , it also undermined the role of the grinding bodies , so as to ensure the sharpness abrasive to complete the entire grinding process. Obviously , in the unit of time , the contact point of the grinding body more involved grinding , i.e., the more abrasive grinding unit of time involved , the higher grinding efficiency . When the abrasive must , to increase the grinding body in contact with the abrasive , the better the smaller the size of the abrasive . On the other hand , to complete the grinding of the workpiece grinding , the grinding capacity must be sufficient impact job . Abrasive task is necessary to ensure sufficient capacity for grinding the workpiece material , and also ensure that the grinding wheel on the workpiece to a certain fineness , therefore , in the case of certain other conditions (e.g., abrasive strength, grinding speed , etc.) , this task only by selecting the appropriate size abrasive and they are reasonable proportion to complete. In theory, the abrasive grinding gap between production is followed by a binding agent to produce coated abrasives, less polymer to achieve the amount of the inorganic binding agent to meet abrasive strength and reaches improve the grinding efficiency purposes , it should be to minimize the gap between the abrasive particles . Another idea that should be adopted to clarify that burns occur when people are accustomed to the work attributed to the set of values abrasive grinding wheel is too dense, the lack of sufficient capacity crumbs pores. Holes in the ground of debris from the chip and chip effect, and can accommodate coolant helps grinding heat dissipation . To meet the special processing requirements, traditional abrasive impregnated pores can also certain fillers such as sulfur and paraffin wax , in order to improve the performance of the abrasive . Such fillers, also known as the fourth element of the traditional abrasive . This is not always correct, because the sheer number of wear debris generated when high- cut grinding , large pore volume are by no means can accommodate small , abrasive and superabrasive wheels although no pores. As long as its surface dressing appropriately can work well . If you increase the pore volume ratio of resin abrasive wheel is bound to reduce its strength, making it premature wear , it is not worth the candle thing. In addition , the linear velocity of the wheel work to produce the quantity of debris is more complex when the grinding wheel increased from 28.8m / s to 33.6m / s , the speed is increased by 16 %, while the blockage increased threefold. Because the wheel speed increases the maximum depth of cut so that the abrasive grains decreases , the cross-sectional area of the chip is reduced , while the number of cutting and grinding heat increases , so that these two factors are increased clogging , but when a high degree of wheel speed ( eg up to 50m / s or more ) the amount of wheel jam but greatly reduced . For a variety of workpiece materials, each with a certain minimum amount of its critical blockage wheel speed values. Inorganic polymer binder produced little abrasive on these considerations , the grinding of these theories will be introduced again in the future special . ) As to ways to reduce high-speed mill burns problem, the following specific abrasive elements will be talked about . Quantitative abrasive particle size distribution and thickness of the extent that the degree of particle size distribution and thickness abrasive . District represented by graded abrasive grading , which means that the thickness of the abrasive used fineness modulus .
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