Why should high viscosity pump gears be nitrided?

Concept: Nitriding is a process of infiltrating nitrogen into the surface layer of steel to improve surface hardness and wear resistance, as well as to improve fatigue strength and corrosion resistance.
It uses ammonia gas to decompose the active nitrogen atom when heated, and is absorbed by the steel to form a nitride layer on the surface and diffuse to the core.
Nitriding is usually carried out using specialized equipment or a well type carburizing furnace. Applicable to all kinds of high-speed transmission precision gears, machine tool spindles (such as masts, grinding machine spindles), high-speed diesel engine crankshafts, valves, etc.
Nitriding workpiece routing: forging - annealing - roughing - quenching - finishing - stress removal - rough grinding - nitriding - fine grinding or grinding.
Since the nitrided layer is thin and brittle, it requires a higher strength of the core structure, so the tempering heat treatment is first performed to obtain the tempered sorbite, and the mechanical properties of the core and the quality of the nitrided layer are improved.
After nitriding, the steel no longer needs to be quenched to have a high surface hardness greater than HV850) and wear resistance.
The nitriding treatment has a low temperature and a small deformation, which is much less deformed than carburizing and induction surface quenching.
Carbonitriding of steel: Carbonitriding is a process of simultaneously infiltrating carbon and nitrogen into the surface of steel. It is customary for carbonitriding to be called cyanidation. At present, the application of medium temperature gas carbonitriding and low temperature gas carbonitriding (ie gas nitrocarburizing) is widely used. The main purpose of carbon monoxide in medium temperature gas is to improve the hardness, wear resistance and fatigue strength of steel. The low temperature gas carbonitriding is mainly nitriding, and its main purpose is to improve the wear resistance and seizure resistance of steel.
Therefore, in general, the high-viscosity pump is required to transport the non-lubricating and high-viscosity material. The high-viscosity pump gear must be nitrided to increase the surface hardness and wear resistance of the gear to prolong the service life of the high-viscosity pump.