A classic feature of Sulzer Z-type engines SULZER ZA, SULZER ZAS, SULZER Z40, SULZER ZA40, SULZER ZA40S is the rotating piston. This Sulzer patented concept with cylinder bores from 90 mm to 420 mm for highly loaded trunk piston engines has the following benefits:

-Even temperature distribution around the piston crown

-Minimum piston skirt deformation

-Optimum sealing and working conditions for the piston rings

-Low and stable lubricating oil consumption thanks to the small piston running clearances

-Smallest risk of seizure between the piston and the cylinder liner