Pressure ranges: 15 to 300 psi Steam, 30 to 125 psi Hot Water Shell Diameters: 36" 15 to 40 HP; 48" 50 to 100 HP; 60" 125 to 200 HP; 78" 250 to 350 HP; 96" 400 to 800 HP; Model Number Nomenclature Guide . The CB Model Number Nomenclature is based on three unique identifiers, each separated by a dash. Identifier #1: Model. This identifies the product model as .