Wartsila CPP 4000mm 4B

A 4 m diameter, four‑blade controllable‑pitch propeller (CPP) made of nickel‑aluminium bronze, rated for about 150 rpm, supplied by Wärtsilä for low‑speed marine propulsion. As a Controllable-Pitch Propeller (CPP), it is normally installed at the aft end of the propulsion shaft with a hub containing the mechanism that rotates the propeller blades about their own axes. In that role, its primary purpose is to vary thrust and reverse thrust direction without necessarily reversing shaft rotation. Compared with an FPP, a CPP adds blade bearings, a pitch-control mechanism and hydraulic or mechanical actuation, which introduces additional sealing and control maintenance. For exact ratings, dimensions, settings, capacities, materials and variant-specific limits, refer to the manufacturer documentation for the exact figure.