2. How to determine the number of pneumatic butterfly valves for ball valves installed in equipment: if the equipment manufacturer has provided such data, the manufacturer's regulations shall prevail; Generally, the installation interval of pneumatic butterfly valves shall not exceed 2M, and the installation quantity of pneumatic butterfly valves for ball valves can be calculated accordingly; If the equipment has channel steel base and the base strength is strong enough, the installation interval of ball valve pneumatic butterfly valve can be appropriately increased and the installation number of pneumatic butterfly valve can be appropriately reduced