Thermal spraying process for tungsten carbide grinding roller for grain and oil mechanical grinding machine

Abstract

The invention discloses a thermal spraying process for a tungsten carbide grinding roller for a grain and oil mechanical grinding machine. The thermal spraying process comprises the following steps ofperforming base material detection before thermal spraying, and determining a base material to be chromium-molybdenum alloy; performing geometric size detection to ensure the surface of a tungsten carbide grinding roller to be free of processing defects and the hardness HRC to be 55-58 degrees; preheating the tungsten carbide grinding roller to be 55-65 DEG C before spraying; starting a powder feeding device to convey prepared tungsten alloy powder to a combustion chamber, performing heating to 1800 DEG C to enable the tungsten alloy powder to be in a molten state; starting a high-pressure fan to spray a tungsten alloy liquid flow in the molten state onto the surface of the tungsten carbide grinding roller at a speed of 840 meters per second; axially moving a spray gun along the self-rotating tungsten carbide grinding roller to form a tungsten alloy coating layer; detecting that the thickness of the coating layer is 0. 02-0.04 mm, the hardness is HV1300 -1500, the surface roughness ofa tooth roller is Ra0.2-0.8, and the roughness of a smooth roller is larger than Ra3.2; and performing marking and boxing on a finished product. The thermal spraying process has the advantages that the tungsten carbide grinding roller is good in chromium-molybdenum base material and free of block falling and stripping and tooth breakage; and a thermal spraying coating layer is high in hardness and resists wear, high temperature and corrosion.

Description

technical field

[0001] The invention relates to a thermal spraying method for tungsten carbide grinding rollers, especially a kind of tungsten carbide for grain and oil mechanical mills with good toughness, no block peeling, tooth chipping, high hardness, wear resistance, high temperature resistance and corrosion resistance Grinding roller (toothed roller, smooth roller) thermal spraying process. Background technique

[0002] The existing grinding roller of the pulverizer adopts the centrifugal casting process. , The surface hardness of the grinding roller is HS70~73. Its process characteristics are loose structure and poor alloy toughness. The surface is easy to fall off and peel off during processing and use, which affects the service life and product quality. Contents of the invention

[0003] In order to solve the above problems, the present invention provides a thermal spraying process of a tungsten carbide grinding roller of a grain and oil mechanical mill with good...