SmartDraw includes thousands of professional-looking diagrams like this that you can easily edit and make your own.
Text in this example:
LIST OF COMPONENTS
A - LUBRICATOR
E - OPEN 2 WAY VALVE
B - PRESSURE GAUGE
G - CLOSED 2 WAY VALVE
C - PRESSURE REGULATOR
H - SIMGLE ACTING CYLINDER
D - FILTER-STRAINER
I - FLOW CONTROL VALVE
FLUID POWER DIAGRAM
[COMPANY NAME]
DRAWN
CHECKED
DATE
DRAWING NO.
(A)
PRESSURE SOURCE
(B)
(D)
(C)
(E)
(G)
(H)
(I)