The cooling of the forged ring is a key procedure that affects the final mechanical properties. The evenly cooled forging ring will produce uniform internal structure and uniform mechanical properties, providing good prerequisites for the next step of heat treatment. For forging rings made of high carbon steel and alloy steel, in order to prevent surface cracking, they need to be piled after forging, using furnace cooling, sand cooling or furnace pre-baking cooling, while preparing for next heat treatment.
When austenitic stainless steel is used as a material, it needs to be poured into water immediately after forging, in order to maintain its existing grain size as soon as possible and prevent grown up. At the same time, it is not desirable to have more internal tissues or particles to be precipitated and then solution treated. All other conventional medium and low carbon steel and medium and low alloy steel forged rings must be air-cooled after forging, in order to make them cool evenly, uniform in structure and uniform in performance, to prevent grain growth and mixed crystals.
Air cooling is a common way for cooling forged rings. Some rings need to be padded between upper and lower layers when piling. Usually calculated at 10% height, that is, the 1000mm section should be padded 100, 2000mm, padded 200, and so on.www.morayshaft.com