Plasma arc is a kind of high-temperature ion gas produced by ionization of ion gas, which is ejected from the nozzle pores and compressed to form a slender arc column.

This paper introduces the common processing methods of engine valves, explains the application characteristics and applicable scope of each processing technology.

Recent technology has revealed a new engine valve which provides petrol engines with the efficiency as well as the economy of diesels. This new engine valve also displays a more benign and manageable emission when compared with conventional petrol engines.

Engine valve grinding machine is important for the companies who want to create top-quality engine valves. In the past years, the machine has been switched from semi-automatic to automatic technology.

Upsetting forging method is one of the production flows of the engine valve machines. This method is used to collect and upset the metal to create the heads of the bolts. Nevertheless, the equipment utilized for this method has been changed.