"Forged" preferred material hoist gear

  Rope hoist  gear material usually a "forged" because forged itself has high strength, good toughness, ease of manufacturing, heat treatment and so on.
Let me introduce soft tooth surface gears and hardened gear materials and the use of the difference.
      1, wire rope hoist  soft tooth surface gear
      Representing tooth gear tooth surface hardness> = 350HBS, commonly used in carbon steel and alloy steel. This gear for strength, accuracy less demanding situations, round billet after heat treatment for slotting or hobbing.
In determining the large and small gear hardness should pay attention to the pinion tooth surface hardness than the large gear tooth surface hardness 30-50HBS. This is because the pinion gear under load more than the number, and the pinion gear tooth root is thin, the gear teeth of the two nearly equal intensity, the pinion gear tooth surfaces of the tooth surface than stiffer.
      2, hardened gear
      Hardened gear tooth surface hard <= 350HBS, commonly used material for the carbon steel or carbon steel with surface hardening treatment, hardness up to 40-55HRC. Use of a low-carbon steel or carbon steel, carburizing required quenching, the hardness of up to 56-62HRC. Require grinding after heat treatment, such as the internal gear grinding is not easy, can be nitriding treatment.