| Refiner plate is an easily broken part of high consistency disc refiner. Its service life span directly affects pulp quality and production efficiency. This paper studied the new precision form technology of long life pulp refiner plate. The main results followed as:Failure modes and theories of refiner plate were studied systematically. It was found that failure of refiner plate is caused by the compound action of wear abrasion, tooth breakage, erosion, corrosion and bar rounding etc. Wear abrasion is caused by galling fatigue. The procedure is that pore occurred at the side of matrix and carbide firstly. Then cracks begin to generate with pore extending. At last matrix and carbide fall off, because of crack extending and connecting. Corrosion is not only affected by potential difference between tooth and groove but also by between matrix and carbide.Erosion failure was systematically analyzed and the necessary condition criterion of erosion formation was deduced. It was considered that bubble generation is caused by pressure loss of refiner area, which is the necessary condition of erosion generation. The criterion is ≤0. When this formula value is less than or equal to zero, the bubble easily generates. Bubble blast attacks tooth area. The compound action of bubble blast and jet fluid results in material damage.The effects of element C, Cr, Mo and Ni on the properties of high chromium alloy material have been investigated. The more increases C content, the more improves hardness of high chromium alloy material and the less impact toughness. Hardness and impact toughness rise with increasing Cr and Mo. Hardness decreases with increasing Ni, but impact toughness firstly increases, then decreases. The new refiner plate material-Cr27Mo2Ni-GT is optimized and developed. By using ultrasonic vibratory method, rotating method, polarization curve method and sliding friction method, the different material properties of erosion resistance, corrosion resistance, scour resistance and frictional wear resistance were investigated. It was demonstrated the material with flaky carbide have good properties of erosion resistance, corrosion resistance, scour resistance and frictional wear resistance. Net carbide badly affects the material properties and results in every index being the lowest. Island carbide has better properties than flake carbide on corrosion consistence and erosion consistence. But its properties are not as good as material with flake carbide on scour resistance and frictional wear resistance. At the same time it was proved martensite structure has better properties than austenite on corrosion resistance, erosion resistance and scour resistance.It was presented that the shell precision casting process composed of back sand and facing sand with chilling, high strength and low gas-forming properties. A set of molding process and equipment was designed. Pouring parameters were optimized. Pouring temperature of small refiner plate was 1520℃. Pouring time was 2-3s. F直:F横:F内 was 1.25:1:1.72. Pouring temperature of large refiner plate was 1610℃. F直:F横:F内 was 1:1.42:3.28. Generation of pore by gas, shrinkage, dispersed shrinkage and cold shut was prevented by presents ways. Dimensional accuracy of stably produced casting was CT8. Tooth face roughness was Ra3.2um. Its life span met design requirement. Produced casting by using this precision process was extensively used in many plants.
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