Towards a comparative study of quarter-turn pneumatic valve actuators

Comparative design studies are potentially a valuable source of design knowledge, surveying as they do the work of many designers in many companies and incorporating the judgement of the market-place. Quarter-turn pneumatic valve actuators are a good product to study, as they are small and self-contained and used in large numbers, and there are many makers (many more even than were expected). Experimental tests were made on nineteen designs. Criteria for comparison were found, and applied, measuring efficiency, matching and compactness. Some explanation of the diversity of designs was found in niches in the market, for example for different valve types and applications. Historical trends have generally been to greater refinement. Some function costs are given. The industry has shown serious interest in this work.