MET230L: Hydraulics and Pneumatics Lab

MET230L: Hydraulics and Pneumatics
Lab
Unit 3 Lab Assignment
Remember to open a new Word file named
MET230L_Unit3_Lab_LastName_FirstName.doc(x) if you have not done so yet.
Exercise 1
This exercise introduces time delay valve (s).
Consider the figure shown.
a. Give the complete name of the component T1.
Time delay valve, normally closed
b. In less than three line, briefly describe how it (T1) works
The time delay valve is actuated by a pneumatic signal at port 12 after a
preset time delay has elapsed. It is returned to the normal position when the
signal is removed. The time delay is infinitely adjustable by means of a
regulating screw. The time delay is reset automatically within 200 ms.
c. In the simulation software assigned by your instructor, open a new file named
Unit3_LabEx1_LastName_FirstName
d. Build the circuit using the components shown or their equivalents
e. Start the simulation by left clicking the start button circled in red as shown (
).
f. Set the opening of valve F1 to 10%
g. With the cylinder fully retracted, left click once on valve M1
 What happens to the cylinder rod?
The cylinder rod starts to extend, until the cylinder rod is fully
extended. After the cylinder rod is fully extended, then the cylinder starts
to retract. When it is fully retracted, the cylinder rod stops.
h. What happens immediately when the cylinder is fully extended?
 After the cylinder rod is fully extended, then the cylinder starts to
retract. When it is fully retracted, the cylinder rod stops.
i. When does the time delay occur? At the beginning of the extension or
retraction stroke?
 Time delay occurs at the beginning of the retraction stroke
j. Is the delay that occurs time on- or time off-delay? It is a timer-on delay
 Why? After the input is turned on, there is a delay before the output
valve is switched/turned on.
k. What valve (s) need to be actuated for the cylinder to extend? S1 and M1
valve
l. What valve (s) need to be actuated to retract the cylinder? S2 valve
MET320L U3Lab Page - 1 -

m. Take a screen shot of the working simulated circuit, copy and paste in the
word document
n. Save the simulation and word files
Figure 1 Circuit to be modeled for exercise 1
MET320L U3Lab Page - 2 -

Figure 2 – Actuated circuit for Exercise 1
The actuated circuit for exercise 1 is shown in figure 2. As soon as the circuit is
actuated, the pneumatic is barred to reach the piston for forward movement. The
5/2 way valve lets the pressure to reach retracement end of the piston.
When valve M1 is actuated, The 5/2 way valve is actuated to let the forward
pressure go to piston as shown in figure 3(A), this is an intermediate stage. As soon
as the piston fully extends, the reverse pressure, reverse pressure from valve R1
reverses the 5/2 way valve and closes it and hence the reverse pressure reaches
the piston and it starts retracting back and comes back to initial position as shown
in figure 3(B).
(A)
MET320L U3Lab Page - 3 -

(B)
Figure 3. (A) Forward extension of piston rod when valve M1 is actuated, (B)
Retraction of piston rod by reverse pressure by closure of 5/2 way valve
Finally the circuit comes to its actual actuated flow form as shown in
figure 2.
Exercise 2
This exercise shows the interconnection between the motions of two cylinders.
Consider the figure shown.
a. In the simulation software assigned by your instructor, open a new file named
Unit3_LabEx2_LastName_FirstName
b. Build the circuit using the components shown or their equivalents
c. Start the simulation by left clicking the start button circled here in red as
shown ( ).
MET320L U3Lab Page - 4 -