During Vacuum Arc Remelting process

deeper shrinkage cavity usually appears on the top of the largesize finished titanium alloy ingot

which also causes the high discarding amount of the ends.The reasons causing shrinkage cavity were analyzed

and the principle and method to design the parameters of hot topping were described.Thus

the hot topping system suitable for the production was determined which reduced the depth of the shrinkage cavity and increased the yield rate of the finished ingot greatly.