Valve disc for exhaust valve of marine diesel engine and fully-coating surfacing alloy technology of valve disc

• Main Authors: TONG CHANGBING, BAO HAIBEI, JIA LIANJUN, CHEN WENBIN, HU QIXIANG, ZHONG AIDONG, ZHAO DAZHONG, LU HONG
• Format: Patent
• Language: Chinese; English
• Published: 16.11.2016
• Subjects: CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

The invention discloses a valve disc for an exhaust valve of a marine diesel engine and a fully-coating surfacing alloy technology of the valve disc. The valve disc comprises a step-shaped base layer connected with a valve rod, wherein an alloy layer is arranged on the periphery of the base layer through surfacing; the base layer comprises a first step and a second step, the second step comprises an inclined surface, a side surface and a bottom surface, and cross sections of the inclined surface, the side surface and the bottom surface are wedge-shaped. The surfacing technology comprises five steps as follows: preparation before welding, treatment before welding, weld machining, postweld treatment and quality inspection. The valve disc reaches technical performance indexes which cannot be realized by the exhaust valve processed without adopting the technology. The solid solution strengthening type nickel-base wrought superalloy has excellent corrosion resistance and high oxidation property, has good tensile p