COOLING OF THE WATER INNER COOLED PIERCING PLUGS

On the basis of an investigation on the water inner cooled piercing plugs used in some ф76~100mm pipe mill trains the invalidity and its cause of the plugs are analyzed. The service life of the water inner cooled piercing plugs is greatly increased after modifying the inner hole design of the plugs, adjusting the cooling water pressure and changing the ratio between the input and output water.