1. Instrumentation and Control Drawings
Unit 23
Instrumentation and Control Drawings

2. Learning Objectives Describe the types of control diagrams.
Identify symbols used on fluid power diagrams.
Recognize supplementary information accompanying circuit diagrams.
Read a graphic diagram.
Interpret graphic diagrams for fluid control devices.

3. Graphic Diagram
Components and piping are shown as schematic symbols

4. Pictorial Diagrams
Components are shown in a pictorial form and piping shown as lines

5. Cutaway Diagrams Components are shown in a cutaway form
Emphasizes the internal functions and connections

6. Combination Diagram
Components and piping shown as graphic symbols, in pictorial, or as cutaways
Describes the purpose of the diagram

7. Instrumentation and Control Diagram Terminology
Accumulator: Container in which fluid is stored under pressure as a source of fluid power
Actuator: Device for converting fluid power energy into mechanical energy
Examples include motors and cylinders
Circuit: Complete path of flow in a fluid power system

8. Instrumentation and Control Diagram Terminology
Component: Single hydraulic or pneumatic unit
Control: Device used to regulate the function of a component
Enclosure: Housing for components
Indicated by a center line rectangle in diagrams
Fluid: A liquid or gas

9. Instrumentation and Control Diagram Terminology
Port: End of a passage in a component
Reservoir: Container for storage of liquid in a fluid power system not under pressure
Restriction: Area in a line or passage with a reduced cross section that produces a pressure drop
Sometimes called an orifice

10. Fluid Power Diagram Symbols
In a diagram, lines can be solid or dashed and may include dots or arrows to assist the print reader with interpreting the circuit

11. Fluid Power Diagram Symbols

12. Fluid Power Diagram Symbols
In a diagram, there are various symbols for valves and other flow-control devices

13. Supplementary Information
The sequence of operations is an explanation of the various functions of a circuit in the order of operation
Solenoids are electrical components used to create reciprocating motion such as for switching
Listed on a solenoid chart
Component lists include the name, model number, quantity, and supplier or manufacturer of components in the circuit
Sometimes called a parts list or bill of materials

14. Reading a Graphic Diagram
Refer to the sequence of operations for this circuit at the end of the unit

15. What do you see?
Print supplied by Talley Industries.