Page 111 - PNEUMATIC SYSTEM INSTRUMENT

QUESTION 3

a. The THREE (3) types of valve actuation method are:

 Manual
 Electric

 Pneumatic
 Mechanical

b. The FIVE (5) disadvantages of the pneumatic system are:

 Only clean air with lowest humidity is allowed to be in

pneumatic system. So, compressed air needs good
preparation to filter any kind of dirt and condensate.

 It is seldom to get uniformed and constant piston speed with
compressed air.
 It has the limitation in producing the output force. It is

suitable for non-heavy-duty purpose.
 The exhaust air is very noisy.

 Compressed air is very expensive in terms of conveying the
power, but the high price is remunerated by the cheap

pneumatic equipment’s, fast and efficient production.

c. A graphic symbol of Push button, 3/2 way normally closed-valve via
spring returned.

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