The unique feature of a slow speed two stroke engine is the sealing between the dirty combustion part and the clean crankcase. The heart of this division is the piston rod stuffing box.
The combination of scraper and sealing rings and lamella scraper rings solves three vital tasks:
HECO piston rod stuffing boxes with scraper and sealing rings have been developed and improved several times in close cooperation with the leading designer of two-stroke diesel engines. The basic principle, however, is unchanged compared to the one Henning Cornelius (founder of HECO) patented in 1962.