Diamond M Company, offshore drilling subsidiary of Houston-based Kaneb Services, Inc., has made three corporate promotions and one staff change, according to Ned E. Simes, president and chief executive officer. Robert E. Rose, formerly vice president contracts and marketing, has been named executive vice president. He joined Diamond M in 1979, and has an extensive background in both drilling operations and marketing.

Mr. Simes also announced the promotion of Roger F. Wise to senior vice president-operations, and R.C. (Chuck) Johnson to director-contracts and marketing. Formerly, Mr. Wise was vice president, worldwide operations, and Mr. Johnson was manager, contracts and marketing. Simultaneously, Mr. Simes announced a staff change involving the appointment of Richard H. Mueller to be director of technical services. Mr. Mueller formerly was director of foreign operations.

Diamond M, the largest energy-related subsidiary within Kaneb Services, currently operates a large fleet of drilling rigs, including semisubmersibles, jackups, platforms, and barge rigs. Three rigs currently under construction, including two semisubmersibles and a posted barge rig, will bring the company's rig fleet to 32 units.