Patent ID: 7270172

Claim:
A process, for forming a metal casting by pouring molten metal into and around a casting assembly comprising an open riser having a cavity containing a sleeve, wherein said process comprises: (a) inserting a riser insert into the cavity of the riser containing the sleeve, and (b) then allowing molten metal to flow into the cavity of the riser containing the riser insert, wherein the riser is shaped such that, or contains a barrier such that, the riser insert does not fall into other parts of the casting assembly before the molten metal is poured, the density of the riser insert is such that the riser insert floats on the surface of the molten metal when the molten metal enters the cavity of the riser, and the sleeve is shaped such that the sleeve holds the floating cover lid in place on top of the metal in the open riser after the molten metal is poured while excess metal is allowed to flow out of the top of the riser.