Our Forged Carbon Steel Shafts, specifically designed for air cooler fans in refineries, are made from CK45 material with a hardness of 35 HRC. These shafts feature dimensions of 2.1875 inches (OD) by 49 inches (length), with a keyway of 0.5 x 0.25 x 6 inches (length). They are ideal for demanding refinery applications.