How to calculate the actual consumption of instrument air?
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Question: 1. Do pneumatic control valves still consume instrument air even when they are not in operation? 2. If one wants to reflect more accurately the actual gas consumption of pneumatic instruments (valves), how should it be calculated? (Don’t estimate 1.3 NM3/h per unit)
http://bbs.hcbbs.com/viewthread.php?tid=296005&highlight=%D2%C7%B1%ED%B7%E7 Check post 5! ! Here is another post on instrument air: http://bbs.hcbbs.com/viewthread.php?tid=373832&extra=page%3D1&frombbs=1. The air consumption of control valves includes the air used by valve positioners and that required for the operation of the diaphragm; 1.3 Nm3/h is assumed for each of these components. Switching the valve consumes 0.3 Nm3/h per operation. If analytical instruments also require instrument air, that amount must be added as well. The total amount obtained after adding these values needs to be multiplied by several factors: 1. The air leakage factor (1.1 can be used in China, while 1 is used abroad, assuming no leakage); 2. A margin for future additional instruments (1.5 can be used in China, while 1.2 or 1.3 is used abroad). This is because plant designs in China are often not well-thought out and subject to frequent changes, whereas plants abroad are rarely modified