Leading Company Specializes In Supplying China Truck Spare Parts

- Nov 26, 2018 -

The valve is composed of the valve head and the rod. The shape of valve head includes flat top, spherical top and trumpet top. Usually flat roof is used. Flat-top valve head has the advantages of simple structure, convenient manufacture, small heat absorption area, small mass, and can be used in both intake and exhaust valves. Spherical top valves are suitable for exhaust valves. They have high strength, low exhaust resistance and good exhaust gas elimination effect. However, they have large heating area, large quality and inertia, and complex processing. The trumpet has a certain streamlined shape, which can reduce the intake resistance, but its head has a large heating area and is only suitable for the intake valve.

Valve cone angle is the angle of valve sealing surface, generally 45 degrees, some are 30 degrees (CA1091 6102 engine). The valve of 30 degree has smaller taper, bigger end face and smaller intake resistance when the lift is the same. However, the valve head with smaller taper has thinner edge, smaller stiffness, poor sealing and thermal conductivity, so it is generally used in the intake valve. Valve edge thickness is generally 1 ~ 3 mm to prevent damage or burning at high temperature due to impact with valve seat in work. In order to reduce the intake resistance and improve the intake efficiency of the cylinder, most engine intake valves are larger than exhaust valves. The used intake and exhaust valves are also different in color.

The valve stem is cylindrical in shape. It moves repeatedly in the valve duct. Its surface must be heat treated and polished. The shape of the end of the valve rod depends on the fixed form of the valve spring. The commonly used structure is to fix the spring seat with two half locking plates. The end of the valve rod has ring grooves to install the locking plates. Some are fixed with locking pins, and the end of the valve rod has a hole for installing the locking pins.