A Quick Clarification on the Pneumatic Symbol. I am very new on Pneumatic schematic Diagram.

[JM333]

Hi,

i am kinda confused on the Exhaust symbol in Pneumatic diagram, where i see schematic drawings on the exhaust port either label as exhaust or label as exhaust with connection using triangle symbol. Which is the correct representation on the exhaust or exhaust with connection.

Could some 1 assist to clarify on this as i am new to this work. i have attached a link to illustrate on what i meant.


[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1622435425/tips/Exhaust_symbol_cbau3f.pdf[/url]

 

[Compositepro]

Most exhaust ports are threaded, and this is shown by a short line with the exhaust triangle at the end. The single acting cylinder shown in your example has a spring on one side of the piston. The airspace around the spring is vented to the out side through a hole drilled in the body. Therefore the exhaust triangle is shown attached to the cylinder body with no line in-between. In many cases this exhaust triangle is not even shown because it is not part of the pnemnatic circuit, although the vent is important for the air cylinder to operate properly.

 

[srini1785]

The symbol shown on the left is that of a 3/2 spring return valve. For such a valve, Port 3 is exhaust while port 1 is supply and Port 2 is connected to the actuator. Valves are threaded and exhausts are directly connected to them. The symbol shown on the right (inside a red circle) is a quick exhaust valve. This is used for venting out the cylinder for rapid return. This is different from a simple exhaust and is (in many cases) directly connected to the cylinder or whatever actuator that is used.

Further note, exhausts are also called as silencers. Photos of threaded, ducted and quick exhaust valves are attached for your reference.