TULSA, OKLAHOMA—  Thompson Manufacturing, who manufactures rules as well as fabricated steel carts and racks, has purchased the assets of H.S. Boyd Co. These two companies had been direct competitors for years in the offset inline perf and scoring markets.  H. S. Boyd Company, Tulsa, Oklahoma has for 50 years  manufactured Inline Offset Cutting and Perf Print Plus die cutting systems. Litho-Perf, Litho-Score and Micro-Perf were for perforating, scoring on offset presses and were sold by dealers across North America. Founded in 1982, Thompson Manufacturing also of Tulsa, built envelope feeders, conveyors, Ferrell Bindery Carts Thompson also manufactures perforating rules, dies and plate correctors. This merger reflects the continuing consolidation of suppliers to the graphic arts industry worldwide .