Grinding method

The flexible abrasive polishing tools and polishing media particles or other modification of the surface of the workpiece processing. Polishing can not improve the dimensional accuracy of the workpiece or geometric shape accuracy, but to obtain a smooth surface or specular gloss for the purpose, sometimes to eliminate gloss (extinction).
Usually buff as a polishing tool. Buff general use multi canvas, felt or leather crafted stacked on both sides with a metal circular plate clamped its rim coated abrasives and grease, etc. from the powder mixture evenly polish. Polishing, buff rotating speed (peripheral speed of 20 m / sec or more) is pressed against the workpiece, the abrasive surface of the workpiece and trace rolling cutting, machining to obtain a shiny surface, generally up to the surface roughness Ra0.63 to 0.01 micron; When using non-greasy matting polishing agent, shiny surfaces can to improve the appearance of extinction.
Mass production of steel ball bearings, often using barreling approach. Rough polishing will be a lot of balls, lime and abrasives on pot-shaped drum tilted, the drum rotates, the ball and abrasive in the barrel rolling crash at random convex front surface to achieve the removal of the surface roughness is reduced purpose, can remove a margin of about 0.01 mm.
Fine polishing ball when loaded in barrels and fur pieces, available hours continuous rotation dazzling bright surface. Polishing precision line scale is machined surface immersed in, carried abrasive powder, polishing powder, polishing powder particle size W5 ~ W0.5 by the alumina powder and cerium oxide powder combined together. Uniform fine polishing using material degreased thin wood or a special felts, its trajectory uniform dense mesh, the surface roughness after polishing is less than Ra0.01 microns, the enlarged 40 times under the microscope than any surface defects. There are also other methods electrolytic polishing.

Purpose and nature of black silicon carbide quality specifications

A black silicon carbide is silicon carbide, refractory materials can be used, it can be used as the abrasive, and green silicon carbide similar are hexagonal crystals, a specific gravity of 3.20 ~ 3.25, microhardness of 2840 ~ 3320kg/mm2.
Black silicon carbide is composed of quartz sand, petroleum coke, wood and other raw materials at high temperatures in a resistance furnace smelting, its hardness between corundum and diamond, the mechanical strength is higher than corundum, brittle and sharp.
1 properties
Great hardness of silicon carbide, with excellent thermal and electrical conductivity, high temperature anti-oxidation.
2 Uses
(1) as an abrasive, can be used for abrasives, such as grinding wheel, Whetstone, grinding, sand tile etc..
(2) as a deoxidizer and high temperature metallurgical materials.
Silicon carbide has four major application areas, namely: functional ceramics, advanced refractories, abrasives and metallurgical raw materials. Currently a large number of silicon carbide coarse material has been able to supply, can not be considered high-tech products, and high-tech application of nanoscale silicon carbide powder is impossible to form a short time scale economies.
(3) high-purity single crystal, can be used for manufacturing a semiconductor, manufacturing a silicon carbide fibers.
3. Origin, exports to the country and quality specifications
(1) Place of Origin: Qinghai, Ningxia, Henan, Sichuan, Guizhou and other places.
(2) exports to country: United States, Japan, Korea, and some European countries.
(3) Specification:
① grade silicon carbide abrasive technical conditions at GB/T2480-96.
② abrasive particle size and composition according to GB/T2477-83. Abrasive grain size determination method according to GB/T2481-83.
Carbide such as silicon carbide refractory itself into the smelting industry also faces significant changes in the performance of pressure, high purity, high toughness, high density silicon carbide, it is in many performance with ordinary silicon carbide has a relatively large difference.
It is not only good toughness, bulk density, water absorption, porosity and purity silicon carbide and other indicators are normal can not be compared, is that it is most advantageous when processed into powder, chemical composition is not reduced, chemical and physical properties maintain the original features. For this reason, high-purity, high toughness, high-density silicon carbide is held in high esteem, the high-quality silicon carbide products for a variety of high-tech fields.

SiC ultra-fine grinding works

SiC ultra-fine grinding works:
Material into the grinding chamber, the spindle is rotated by the rotation of the roller swings outward centrifugal force, roller pressed on the grinding ring, shovel blade materials to the grinding roller and grinding ring, between the grinding rollers and grinding ring rolling and under pressure between the material repeatedly roll crushing, sandblasting abrasive in the grinding chamber and lead mixed into a fluidized air flow.
In the classification round lead centrifugal action of the wind and the system to achieve the thickness of separation, does not meet the size requirements of coarse crushing area to continue falling back pulverized into powder qualified grading machine for sorting, finer powder into the cyclone collector after , the centrifugal force, along the cyclone powder rotating cylinder wall is decreased, the end of the inner cone is separated, after the separation into the pulse finer powder collector, the purified gas into the atmosphere via the induced draft fan. A negative pressure state in the whole system work.
Production process: feeding → Host → grading machine → cyclone collector → → pulse collector fan.

Corundum powder processing process

Fine polishing abrasive grinding process-flow indispensable processing materials. As part of the diversity, there must be a corresponding fine polishing abrasives.
Corundum, white corundum, white corundum, with a homogeneous, suitable hardness, wear resistance, etc., use unbreakable to technical appraisal by experts, to fill the gaps, reached the international level of similar products to replace imports, with the kind polisher machines.
Corundum powder is used in ultra-fine grinding of a computer chip components, electronic communication products silicon components, rocket engine temperature component, high temperature gas turbine blade components, such ultra-fine grinding corundum powder production methods, based on aluminum hydroxide as raw material, after calcination, grinding, pickling, grading and drying to obtain, for the particle size of 40 microns or less fine powder, classified by hydraulic sedimentation method, from fine to coarse classification carried out in the first level of fine, coarse level, after that , the classification is completed until all.
Classification method in the strict control slurry concentration, settling time, while the siphon height, adding an efficient dispersant, the dispersant molecule in water between aggregated particles interspersed, including all attached to the periphery of particles of different sizes, by dispersant molecular charge repulsion, the particles can no longer get together, both to improve the accuracy of such classification, but also makes the final product can be kept loose state.

 

Five use of corundum

Corundum has the following five main scope of use
1 free grinding - grinding grade abrasives used in kinescope, optical glass, silicon, lenses, clocks, glass, crystal glass, jade and other areas of freedom ground, is commonly used advanced abrasive materials.
(2) Sandblasting corundum - blasting abrasive hardness, high packing density, no free silica, heavy, good toughness, Okay corundum is the ideal "green" blasting material, widely used in aluminum , copper profile glass, washed jeans precision molds and other fields.
3 Resin Abrasives - Abrasives has the right color, hardness, toughness, suitable particle cross-section type and edge retention, resin abrasive used, the results are satisfactory.
4 filter media - is a new type of abrasive applications, the use of particulate abrasive medium as the bottom of the filter bed, to purify drinking water or waste water, is home to a new water filtration material, particularly suitable for non-ferrous metal processing: oil drilling mud weighting agent .
5 corundum functional filler - mainly used for automobile brake parts, specialty tires, specialty building products in areas such as construction of motorways. Airstrip. Pier. Parking. Industrial floor. Stadium and other wear-resistant materials .

 

Corundum is abrasive blasting is the best choice

Corundum is bauxite, coke (anthracite), iron as the main raw material, and then electric arc furnace melting temperature crystallization, it has a hardness, toughness, particle Fengrui, grinding power, high temperature, high efficiency, is the quality of abrasives materials and advanced refractories. It is made with abrasive, for grinding high tensile strength of the metal can be cut, grind a variety of common steel, carbon steel, general steel, malleable, Qingdao Steel, hard Qingdao Steel, etc., can also be As advanced refractory, widely used in iron and steel, chemical and other industries abrasive blasting with high-quality corundum as raw materials using modern new unique technology is refined. Abrasive blasting abrasive short time, high efficiency, good benefits, and low prices of the product hardness, high toughness, good self-sharpening, sand consumption is low and can recycle and reuse, grinding pieces of finish is good; and chemical composition and stability, resistant, acid and alkali. The abrasive shell-shaped fracture, sharp corners, constantly smashing step in the formation of new edges and the side edge, making it superior to other abrasive grinding capacity. In particular it has a high hardness, specific gravity, chemical stability and its unique self-sharpening, etc. become sandblasting abrasive of choice; while it is sand-blasting cleaning workpiece. Workpiece material blasting purpose craft to stainless steel surface decontamination, in addition to welding slag and matte effectCorundum use1 Iron piece: to rust, decontamination, descaling, increasing the coating, the coating adhesion2 aluminum workpiece: descaling, surface hardening, light decoration effect3 copper artifacts: Go oxidation Pia light effect4 Crystal glass: frosted, engraved pattern5 Plastic products: matte effect6 denim and other special fabric: plush processing and effectsBlack corundum abrasives are high quality bauxite as main raw material, add less then a reducing agent in smelting electric arc furnace at high temperature, the color black. Hardness, toughness greater wear sharp edges and corners, and strong self-sharpening, grinding is less heat, high polished workpiece cleaning, domestic production of water purification materials, professional manufacturers, strong technical force, excellent equipment, advanced technology , there are more than ten series kind, hundreds kinds of products, the Ministry of Construction as a professional product promotion manufacturers. The products are widely used for urban water supply, drainage, metallurgy, electric power, industrial wastewater treatment and other fields.

  

Silicon carbide products using methods and protection methods

Silicon carbide products using methods:
Prohibit the use of silicon carbide products overload, if rod appearance showing blistering appearance, often stick temperature is too high or harmful substances and stick response, should seek to decrease temperature or reduction of harmful substances stick with great touch. Surveys often use the appearance (voltmeter, ammeter, thermometer, etc.) whether the normal readings, showing abnormal timely adoption of appropriate measures to find the cause. Silicon carbide devices and connection to the furnace after. It should be loose in the axial and lateral clearance can move and change, the prohibition of forced or hard metal plates mounted plug the stick force convergence, avoiding thermal expansion force after power increase and broken rods. The cold end of the fixture and stick spray aluminum end convergence to be fastened.
Silicon carbide products protection methods:
Stick in the Deposits must pay attention to moisture; rod ends are found sprayed aluminum layer deliquescence fall; should scratch sprayed aluminum disposal can also be sprayed aluminum rods wrapped layer of aluminum foil wiring segment after use. Using bolt type clamps, the need to run for some time before tightening again, to prevent loosening clamps and rods touch bad. Water vapor will promote accelerated aging silicon carbide products; if there is water in the heating process of discharge, on the need to leave the furnace vent. New furnace or kiln from lack of use, before using the oven.
Oven as much as possible the use of other sources of heat or stick with the old. There are other corrosive atmosphere furnace, in the case of promise, but also left on the furnace vent. To adhere to the furnace temperature is normal, in the process with the use of silicon carbide rod resistance value added, should be gradually progressive use of voltage, when the voltage transformer used to progress to the highest limits of silicon carbide products equipment still can not meet the pleading, you can choose to change shutdown great way to continue using wiring methods. If excessive aging should be fully shutdown using a new stick.
Silicon carbide has a brittle ceramics; transporting, unpacking, installation, replacement process to gently prohibit or mechanical strength sensational hit, to avoid breakage.