Types of Valves, Guides, and Bearings
Valve types include intake and exhaust valves for diesel and gasoline engines, made from chrome-molybdenum steel with 55-60 HRC surface hardness to withstand temperatures up to 600°C and gas pressures up to 200 bar. Valve stem diameters range from 6 to 12 mm, with lengths between 80 and 150 mm. Accurate operation is ensured by hardened valve seats, providing gas leakage below 0.05 mm.
Valve guides are made from alloy steel with nickel coating and 50-55 HRC hardness, ensuring precise valve movement along the shaft and wear reduction up to 0.1 mm. Bearings include metal and graphite bushings capable of handling axial and radial loads up to 50 kN and operating temperatures of 150°C. Lubrication uses VG 32 to VG 68 oils, and vibration and pressure testing according to ISO 1940 ensures a service life exceeding 10 years.
