COKE SCRAPING RING, CYLINDER LINER, CYLINDER, GAS ENGINE AND GAS ENGINE OPERATION METHOD

The present invention pertains to a coke scraping ring 10 for a cylinder liner 100 of a cylinder 200 used in a gas engine, for scraping carbonaceous residuals R off a top land 210 of a piston (220, Fig. 1), comprising a ring body (12, Fig. 2), a top end (14, Fig. 2), a bottom end (16, Fig. 2), and a combustion-facing side (18, Fig. 2) configured to be in direct contact with combustion products during operation; the coke scraping ring 10 further comprising a scraping ring section 20 at the bottom end (16, Fig. 2) and a recess ring section 22 configured to provide a recess (23, Fig. 3) in the combustion-facing side (18, Fig. 2); The present invention further pertains to a cylinder liner 100 comprising such scraping ring 10, to a cylinder 200 comprising such cylinder liner 100, to a gas engine comprising such cylinder 200 and to a gas engine operation method comprising continuous scraping carbonaceous residuals off a top land 210 of a cylinder piston (220, Fig. 1), comprising the steps of assembling (S10, Fig.12) a cylinder piston (220, Fig. 1), a coke scraping ring 10, a cylinder liner 100, a cylinder crank case 240, and a cylinder head (230) to obtain a ready-to-operate cylinder 200, operating (S20, Fig. 12) the cylinder 200 while scraping excess carbonaceous residuals off the top land of a cylinder piston, and observing (S30, Fig. 12) no pressure-induced deformation on the cylinder piston (220).