Process for producing cast iron castings with a vermicular graphite structure
AssigneeGeorge Fischer Ltd.
InventorsReinhold Linkert, Emil Becker, Horst Hoffmann
Life of this patent
Estimating the term…
Abstract
Cast iron with a vermicular graphite structure is produced by a process which involves the steps of determining the ratio of magnesium to sulphur in the melt and then adjusting the value of such ratio to between about 0.8 and 2.5.
Claims21
A process of producing cast iron with a vermicular graphite structure, comprising the steps of:
- determining the ratio of Mg to S in the melt;
- and
- adjusting the Mg/S ratio of the melt to a value of from about 0.8 to about 2.5.
A process of producing cast iron with a vermicular graphite structure, comprising the steps of:
- determining the Mg/S ratio in a melt;
- adding a sulphur compound when the Mg/S ratio is greater than about 2.5;
- adding a magnesium compound when the Mg/S ratio is less than about 0.8;
- and
- repeatedly adding the compounds until the Mg/S ratio is within the range of about 0.8 to about 2.5.
A process for producing cast iron with a vermicular graphite structure in a converter, wherein the initial melt has a sulphur content of up to about 0.3 percent, comprising the steps of:
- determining the Mg/S ratio in the melt;
- adding a sulphur compound when the Mg/S ratio is greater than about 2.5;
- adding a magnesium compound when the Mg/S ratio is less than about 0.8;
- and
- repeatedly adding the compounds until the Mg/S ratio is within the range of about 0.8 to about 2.5.
Dependencies are inferred from the claim text.