subject: Abrasives common sense: low hardness grinding wheels should hardness workpiece - Hardware, grinding, abrasive - Hardware Industry [print this page] Abrasives common sense: low hardness grinding wheels should hardness workpiece - Hardware, grinding, abrasive - Hardware Industry
Grinding wheel in the grinder as a cutting tool with the workpiece cutting method. The method is characterized by:(1) As the grinding wheel grit their high hardness and heat resistance, the grinding process can be very hard materials such as hardened steel, carbide and so on.(2) grinding wheel and grinding characteristics of the system can determine the uniformity of the micro-cutting for the general ap = 0.001 ~ 0.005mm; grinding speed is high, generally up to v = 30 ~ 50m / s; grinding stiffness good; with hydraulic drive, so can the economy grinding to obtain a high precision (IT6 ~ IT5) and small surface roughness (Ra = 0.8 ~ 0.2 m). Parts finishing grinding is one of the main methods.(3) because of strong friction, Ershi high grinding zone temperature. This will cause the stress and deformation of the workpiece, causing the surface burns. So a lot of grinding coolant must be injected to reduce the grinding temperature. Chip and coolant lubrication can also be played.(4) large radial force when grinding. This will result in machine tools? Wheel? Workpiece system flexibility concessions, the actual depth of cut less than the nominal depth of cut. So grinding will be complete, should not feed for light grinding to remove the error.(5) after blunt abrasive grinding, grinding force also increased, resulting in particle fragmentation or loss, re-exposed sharp edge, this feature is called "self-sharpening." Since Sharp makes grinding a certain period of time to normal, but over a certain time after work, man should be trimmed so as not to cause the grinding force increased vibration, noise and damage the workpiece surface quality.Wheel Grinding wheel is a cutting tool, which consists of many small, hard, abrasive and adhesive binder made of porous objects. Abrasive cutting directly responsible for the work, must be sharp and have high hardness, heat resistance and a certain toughness. Commonly used abrasives are aluminum oxide (also known as alumina) and silicon carbide are two. Alumina abrasive type, high hardness, good toughness, suitable for grinding steel material. Type silicon carbide abrasive hardness higher and more sharp, good thermal conductivity, but more brittle for grinding cast iron and hard alloy.Same abrasive grinding wheel, different because of its thickness, surface roughness of workpiece after processing and processing efficiency is not the same as coarse grit for rough grinding, fine abrasive for grinding, the coarser abrasive particle size smaller number.Bond from bonding abrasive effect. Commonly used is bond, followed by the resin bond. Binder choice of materials with different impact wheel corrosion resistance, strength, heat resistance and toughness.Abrasive bonded more firmly, the more difficult from a wheel fell off on the hardness of said grinding wheel, grinding wheel hardness means that the surface of the abrasive wheel under loads off the difficulty. Easy to fall off as soft, otherwise known as hard. Hardness and abrasive grinding wheel hardness are two different concepts. By grinding the workpiece surface is relatively soft, abrasive the edge (edges) on easy to wear, so the time can be abrasive to use longer, more solid bond that is optional wheel (wheel hardness higher). Conversely, low hardness for grinding wheel hardness of workpiece.Wheel at high speed under the conditions of work, in order to ensure the safety inspection before the installation, there should be no cracks and other defects; order to wheel and steady, dynamic balance test should be carried out before use.Wheel working after a certain time, the surface debris to plug the gap will be, will be blunt abrasive acute angle, the geometry of the original will be distorted. Must be repaired to restore the cutting ability and the correct geometry. Xu Yong wheel dressing diamond pen.Grinding surface grinding machine structure and movementMany different types of grinding machines, mainly surface grinder, cylindrical grinder, internal grinder, universal cylindrical grinding machine (which can grind the hole), gear grinding, thread grinding machine, rail grinding, centerless grinder (grinding cylindrical) and tool grinder (grinding tool) and so on. Here are surface grinder and its movement.1. Surface grinding machine structure (with M7120A, in which: M?? Grinder type machine; 71?? Horizontal spindle and rectangular desktop surface grinding; 20?? Work surface width of 200mm; A?? The first major improvement.)(1) wheel rack?? Install wheel and drive wheel for high-speed rotation, the wheel frame can slide along the dovetail guide for manual or hydraulic horizontal clearance campaign.(2) slide?? Install wheel drive wheel frame and guide frame for moving up and down along the column.(3) column?? Bearing slide and wheel frame.(4) table?? Install a workpiece driven by the hydraulic system for reciprocating linear motion.(5) bed?? Supporting table, the installation of other components.(6) coolant system?? To provide coolant to the grinding zone (saponified oil).(7) hydraulic system?? Its composition: 1) dynamic element?? For the oil pump, oil supply pressure of hydraulic drive system;2) implementation of the components?? For the tank, driving table and other parts movement;3) control components?? For a variety of valves, pressure control, speed and direction;4) auxiliary components?? Such as tanks, pressure gauges.Hydraulic and mechanical drive transmission compared to a smooth, can overload protection, can be achieved in a large range of variable speed advantages.2. Grinding motion (1) the primary campaign?? Wheel, high-speed rotation.(2) feed motion 1) vertical feed?? Table driven parts of the reciprocating linear motion;2) vertical feed?? Wheel depth direction to the movement of the workpiece;3) cross feed?? Wheel gap movement along its axis. http://www.articlesbase.com/rugby-articles/abrasives-common-sense-low-hardness-grinding-wheels-should-hardness-workpiece-hardware-grinding-abrasive-hardware-industry-2685386.html
