Pargas, Inc., of Waldorf has named four new vice presidents to fill management positions in the company's propane marketing operations.

Filling the newly-created position of executive vice president is N. L. Langley, who had been senior vice president in charge of the company's northern division. Langley has been with Pargas since 1946.

William E. Jones has been named vice president and manager of the northern division, replacing Langley. That division handles propane marketing in New York. New Jersey, Pennsylvania, Maryland, West Virginia, Minnesota and part of Virginia.

New vice president in the south central division is Donald E. Rones. Rones replaces Gordon L. Benson, who resigned from the company. Rones, who was most recently executive assistant to the president, has been with Pargas since 1967 when Pacific Delta Gas, Inc., was merged into the company.

R. L. Coleman has been elected vice president and manager of Pargas' southeastern division. That division also includes part of Virginia in addition to North and South Carolina, and Florida. Coleman succeeds the late J. Howard Wheatley.

District-Realty Title Insurance Corp. elected new officers recently.

Former president Jerome Malin was elected vice chairman, Samuel R. Gillman was named president and Vance N. Caskey was promoted to senior vice president.

Gillman has been president of Columbia Real Estate Title Insurance Co. for the past nine years.

The announcement was made by chairman Nelson G. Harris.Harris became chairman in January when District Realty became a subsidiary of Industrial Valley Bank and Trust Co. of Philadelphia. Harris was then president of Industrial Valley Title Insurance Co.

Computer Data Systems, Inc., has promoted Gordon S. Glenn to vice president. Glenn joined CDSI in 1971 and most recently has been program manager.

CDSI also announced that James E. Webb, a private attorney in Washington, has been elected to the board. Webb is a former administrator of the National Aeronautics and Space Administration.

CTEC, Inc., of Falls Church has named Ralph O. Rosenthal vice president. Rosenthal will manage the company's systems analysis and operations research department.

CIMA, a Washington-based risk management firm, has promoted Harry F. Custic to president. Armiger L. Jagoe will serve as the company's chairman.

People National Bank of Maryland has elected John S. R. Schoenfeld to the board. Schoenfeld is executive vice president and director of the International Management and Development Institute.