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—— Chinese—— English

Tie to quality to manage, rely on Innovation to advance,depend on Science and technology to grow

	Rough forming: The balls are formed into rough spheres on cold heading, hot forging, or hot rolling machines.
	Flashing: The balls are ground under pressure between rotating grooved cast iron plates to improve sphericity.
	Heat treatment: The balls are through hardened by heating to 840 ℃ and quenching. They are then tempered to remove excess stresses.
	Hard’ Grinding: The hardened balls are then ground under pressure between a rotating grinding wheel and a stationary cast iron plate.
	Finish lapping: The balls are carefully lapped to their final dimensions between grooved cast iron plates, one rotating and one stationary.
	Inspection: Varies according to grade from 4% AQL for commercial grades to 100% electronic scan and crack detecting for high precision.