Steel valves are the most common in medium-stressed engines. The steels used in this context have different characteristics according to their use:
When the best of the characteristics of the two steels is required, SCARPA & COLOMBO manufacture bimetallic exhaust valves, in which the valve head is made in a material resistant to high-temperatures, while the remaining part (i.e. nearly all the stem) is in toughenable steel and has a greater wear resistance. The two materials are welded together by friction.
At the customer’s request we provide the necessary assistance for the choice of the materials.