Edward Reel Williams, 78, a retired steel company executive and a developer of continuous casting processes for steel, died at Montgomery General Hospital Sunday of complications following a stroke. He had lived at Rossmoor Leisure World in Silver Spring since 1967.

Mr. Williams grew up in Sharon, Pa.; where he was born, and Cleveland, Ohio. He served briefly in World War I. In 1921, he graduated from Yale University with a degree in engineering.

In 1923, he joined the Vulcan Mold and Iron Co. in Latrobe, Pa. He became its president in 1932 and held that position until he resigned in 1946 and moved to Edgewater, Md. For several years thereafter he operated the Williams Engineering Co., specializing in research, patent development and licensing in the metals industry. Mr. Williams was an expert in the continuous casting of steel.

Mr. Williams was a member of the Annapolis Yacht Club and the Annapolis Power Squadron.

Survivors include his wife, Edith Faye, of the home in Rossmoor, a daughter, Elizabeth Hendrich, of Miami, Fla., a brother, David, of Orleans, Mass, three grandchildren and one great-grandson.

The family suggests that expressions of sympathy be in the form of contributions to the Building Fund of the Washington Cathedral.