Fluid Power Transmission Lab Manual_Spring_2025

Plotting a Pump Performance Curve for a Centrifugal Pump

Hydraulic Circuits I: Regeneration and Synchronization

Objectives

• Be able to build and design hydraulic circuits on Automation Studio.

• Understand the function of regeneration circuits and how it works.

• Understand the function of synchronization (in parallel and in series) for hydraulic circuits.

• Understand how to build the circuits on the hydraulic trainer.

Background and Theory

• A simple hydraulic circuit using a double-acting hydraulic cylinder was built in Laboratory 2.

• The piston in the cylinder has two motions: extension and retraction.

  • Extension Stroke: Piston-rod moving to the rod-end side.

  • Retraction Stroke: Piston moving toward the cylinder/blank end.

• Equations for Velocity and Force Calculation:

  • Continuity equation: $v = \frac{Q_P}{A}$

  • Pressure equation: $F = p * A$

  • Where:

    • $Q_P$: pump flow rate

    • $A$: effective area

    • $p$: pressure

• Extension Stroke: Fluid enters the blank end of the cylinder and acts on the entire circular area of the piston ($A_P$).

• Retraction Stroke: Fluid enters the rod end of the cylinder and acts on the smaller annular area between the rod and cylinder bore ($A<em>P - A</em>r$).

• Velocity and Force for Both Strokes:

  • Extension:

    • $v<em>{extend} = \frac{Q</em>P}{A_P}$

    • $F<em>{extend} = p * A</em>p$

  • Retraction:

    • $v<em>{retract} = \frac{Q</em>P}{A<em>p - A</em>r}$

    • $F<em>{retract} = p * (A</em>p - A_r)$

• The velocity of the retraction stroke is larger than the velocity of the extension stroke. To speed up the extension stroke while keeping the retraction stroke velocity the same, a regeneration circuit will be used.

Regeneration Circuit

• Used to increase the extension stroke speed of the piston of a double-acting cylinder while keeping the retraction stroke velocity the same.

• Done by directing the fluid from the rod end during the extension stroke to the blank end instead of going back to the tank.

• One of the directional control valve outlet ports (A&B) that should be connected to the rod end will be blocked; the rod end fluid will be directed to the blank end using a multiple port connector.

• Total Flow Rate During Regeneration Extension:

  • $Q<em>T = Q</em>P + Q_r$

  • $Q<em>T = A</em>P * V_{extend, regen}$

• Flow Rate from the Rod End Side:

  • $Q<em>r = (A</em>p - A<em>r) * V</em>{extend, regen}$

• Regeneration Velocity Equation:

  • $V<em>{extend,regen} = \frac{Q</em>P}{A_r}$

Synchronizing Circuits

• Used when a large mass must be moved, and it is not feasible to move it with just one cylinder.

• Multiple cylinders are used to prevent moments that might distort and damage the load or the cylinder.

• Cylinders must be synchronized for the circuit to operate properly.

• Two ways to synchronize the cylinders in a hydraulic circuit:

  • In parallel.

  • In series.

Synchronization in Parallel

• Two identical cylinders are connected in parallel, sharing the same inlet and exit.

• Both cylinders extend and retract at the same speed.

• For synchronization, the cylinders need to be identical, and the loads on the cylinders must be identical.

• Practically, it is hard to place the load to be carried equally by both cylinders and no two cylinders are identical due to packing (seals) friction differences. This prevents cylinder synchronization for this circuit.

• Flow control valves are needed to be placed at each cylinder to control the flow rate to each cylinder and synchronize both cylinders.

Synchronization in Series

• Two identical cylinders are connected in series where the exit of cylinder 1 is connected to the inlet of cylinder 2.

• During the extending stroke of cylinders, fluid from the pump is delivered to the blank end of cylinder 1. As cylinder 1 extends, fluid from its rod end is delivered to the blank end of cylinder 2, causing the extension of cylinder 2. As cylinder 2 extends, fluid from its rod end reaches the tank.

• The two cylinders are not synchronized because the amount of fluid used to extend the piston cylinder 2 is not enough to fully extend piston since the fluid is coming from the rod end of cylinder 1 where is the rod is taking space reducing the fluid going to cylinder 2.

• For synchronization, cylinder 2 must be smaller than cylinder 1.

• Equation for Synchronization:

  • $Q<em>{out(cylinder \ 1)} = Q</em>{in(cylinder \ 2)}$

  • $(A<em>{Piston \ 1} - A</em>{Rod \ 1}) * v1 = A_{Piston \ 2} * v2$

  • For synchronization: $v1 = v2$

  • $(A<em>{Piston \ 1} - A</em>{Rod \ 1}) = A_{Piston \ 2}$

• The piston area of cylinder 2 must be equal to the difference between the areas of the piston and rod for cylinder 1.

• No matter the load placement, or the number of cylinders in series, each one must be capable of lifting the entire load, otherwise, all the system will be locked.

Experiments Setup and Procedure

• Three activities will be conducted in this laboratory:

  • Construct a regeneration circuit on the hydraulic trainer and simulate the circuit on Automation studio.

  • Construct a synchronization in parallel circuit on the hydraulic trainer and simulate the circuit on Automation studio.

  • Construct a synchronization in series circuit on the hydraulic trainer and simulate the circuit on Automation studio.

Activity #1: Construct Regeneration Circuit

• Equipment: Bosch Rexroth Trainer, a computer with Automation Studio software.

• Procedure:

  1. Before starting the experiment, listen to the instructor’s description of the circuit and follow the safety checklist.

  2. Start the circuit by placing the required components on the trainer.

  3. At the pressure port on the connection header “port P,” place a connector with multiple ports.

  4. Connect a hose from one of the ports of the “multiple ports connector” to the “P” port of the directional control valve.

  5. From port “T” of the directional control valve, connect a hose to the return port “port T” on the connection header.

  6. From port “A” of the directional control valve, connect a hose to the blank end port of the cylinder.

  7. Connect a hose from the rod end port of the cylinder to one of the ports of the “multiple ports connector”. (Don’t connect any connection to port B on the DCV).

  8. Pull out the red safety switch (make sure it is pulled out from both sides of the trainer).

  9. Start the motor by pressing the black button on the side of the white box near to the reservoir, then rotate the control valve (silver arm) to let the flow move through the circuit.

  10. By shifting the directional control valve, the piston should extend and retract at nearly the same speed.

  11. Record the pressure of the circuit (the pressure gage inserted at the P port at the connection header).

  12. Record the time of the piston extension and retraction. What do you observe? Write down your observation and your thoughts about your observation.

  13. Take a picture of the circuit and insert it into your report.

  14. Observe the pressure of the circuit (pressure gage inserted at P port).

  15. Start Automation Studio and build the complete circuit.

  16. After completing the circuit design, simulate the circuit. Observe the extension and retraction speed.

  17. Save a print screen of your circuit and insert a copy in your report.

Activity #2: Build Synchronization in Parallel Circuit

• Equipment: Bosch Rexroth hydraulic trainer, a computer with Automation Studio software.

• Procedure:

  1. Before starting the experiment, listen to the instructor’s description of the circuit and follow the safety checklist.

  2. Start the circuit by placing the required components on the trainer.

  3. Connect two “multiple ports connectors” at ports A&B of the Directional Control Valve DCV.

  4. Connect two hoses from the multiple port connectors at port “A” on DCV to ports "A" on two flow control valves.
     Connect two hoses from the multiple port connectors at port “B” on DCV to the rod ends of both cylinders.

  5. Pull out the red safety switch (make sure it is pulled out from both sides of the trainer).

  6. Start the motor by pressing the black button on the side of the white box near to the reservoir, then rotate the control valve (silver arm) to let the flow move through the circuit.

  7. By shifting the directional control valve, both cylinders will extend and retract (are they synchronized?).

  8. Adjust the flow control valve to synchronize the strokes for both cylinders.

  9. Take a picture for the circuit and insert it into your report.

  10. Start Automation Studio and build the complete circuit.

  11. After completing the circuit design, simulate the circuit. Observe stokes of both cylinders. Comment on the observation in your report.

  12. Save a print screen of your circuit and insert a copy in your report.

Activity #3: Build Synchronization in Series Circuit

• Equipment: Bosch Rexroth Trainer, a computer with Automation Studio software.

• Procedure:

  1. Before starting the experiment, listen to the instructor’s description of the circuit and Follow the safety checklist.

  2. Start the circuit by placing the required components on the trainer.

  3. Connect a hose from the pressure port on the connection header “port P” to the “P” port of the directional control valve.

  4. Connect a hose from port “A” on the DCV to the blank end of cylinder 1

  5. From the rod end of cylinder 1 connect a hose to blank end of cylinder 2.

  6. From the rod end of cylinder 2 connect a hose to port “B” on the DCV.

  7. By shifting the directional control valve, observe what will happen and comment on the observation in your report.

  8. Take a picture for the circuit and insert it into your report.

  9. Start Automation Studio and build the complete circuit.

  10. After completing the circuit design, simulate the circuit. Observe the extension and retraction speed.

  11. Save a print screen of your circuit and insert a copy in your report.

Post Lab Questions

1. What is the function of a regeneration circuit?

2. In a regeneration circuit, would the extension speed increase or decrease if the rod diameter was decreased, why?

3. Could the synchronization in parallel circuit work only with one flow control valve? Why or why not?

4. What are the disadvantages of synchronization in series circuit in terms of force, startup, and adjustments? (if you experience any of them write it down)

5. Which circuit would you choose to synchronize 4 or 8 cylinders, synchronization on series or synchronization in parallel?

Hydraulic Circuits II: Meter-In and Meter-Out Circuits

Objectives

• Understanding the concept of Meter-in & Meter-out flow control.

• Being able to build Meter-in & Meter-out circuits on the Hydraulic trainer.

• Being able to build and design hydraulic circuits on Automation Studio.

Background and Theory

• Meter-in and Meter-out circuit flow control methods are used to control the speed of actuators in any hydraulic (or pneumatic) circuits.

• Meter-in circuit controls the flow inlet to the actuator to control its speed, while Meter-out circuits control the speed of the actuator by controlling the flow outlet.

• A flow control valve should be used to control the flow rate in or out from the actuator.

• A one-way restrictor valve will be used, which meters the flow in one direction while allowing free flow in the opposite direction.

• There are four different available circuits for a double acting hydraulic cylinder:

  • Meter-in extension.

  • Meter-in Retraction.

  • Meter-Out extension.

  • Meter- out retraction.

• The purpose of the circuit and the cost determine which meter circuit to be used. There are certain applications that one of the circuits must be used, while for some, any of the circuits could be used.

• Three different orientations must be considered when deciding which circuit should be used based on the hydraulic cylinder:

  • Horizontal.

  • Vertical.

  • Tilted load.

Horizontal Loads

• The cylinder is either pushing or pulling the load depending on the purpose of the circuit.

• The choice of the circuit will depend on the application, meter-in or meter-out circuits can be used (Meter-in are found to be more used in these applications).

Vertical Loads

• Two different orientations for vertical loads:

  • Cylinder carries load against gravity (cylinder is underneath the load).

  • Cylinder is pulling the load against gravity (cylinder is above the load).

  • There will be a critical stroke that needs to be considered for each of these applications.

• When the cylinder carries the load, the retraction stroke is critical since the load is descending due to gravity which can cause damage to the cylinder (or the load) due to high impact force in addition to the cavitation effect in the cylinder due to the depressurization of the fluid in the cylinder.

  • Meter-in circuit is not recommended to be used to control the retraction stroke since the load will push the fluid in the blank end which is not restricted and can cause strong impact with the cylinder end.

  • Meter-out would be recommended as it controls the flow out during retraction which will cause smooth operation when lowering the load.

• When the cylinder pulls the load, the extension stroke is critical.

  • If the Meter- in circuit is used, damage may occur due to the speed of the load.

  • Meter-out should be used to control smooth operation of the system.

• Pressure Intensification: When Meter-out is used in the previous examples, the pressure at the port where the fluid leaving will increase beyond the pump pressure.

Tilted load

• Similar to vertical loads, Meter-out circuits should be used when designing circuits include tilted loads to protect both the cylinder and the load.

Experiments Setup and Procedure

• Three activities will be conducted in this laboratory:

  • Construct a Meter-in circuit on the hydraulic trainer using a horizontal hydraulic cylinder.

  • Construct a Meter-out circuit on the hydraulic trainer using horizontal hydraulic cylinder and vertical hydraulic cylinder.

  • Construct and simulate a Meter-in or Meter-out circuit on Automation studio.

Activity #1: Construct Meter-In Circuit

• Equipment: Bosch Rexroth hydraulic trainer.

• Procedure:

  1. Before starting the experiment, listen to the instructor’s description of the circuit and Follow the safety checklist.

  2. Start the circuit by placing the required components on the trainer.

  3. Connect a hose from the pressure port on the connection header “port P” to the “P” port of the directional control valve.

  4. From port “B” on the DCV to port “A” on the one-way restrictor valve.

  5. From port “B” on the one-way restrictor valve to the rod end of the cylinder.

  6. From the blank end of the cylinder connect a hose to port “A” on the DCV.

  7. Install four pressure gauges in the circuit: before and after the one-way restrictor valve, near the blank end, and at the connection header to measure the circuit pressure.

  8. Install a flowmeter either before or after the one-way restrictor valve.

  9. Pull out the red safety switch (make sure it is pulled out from both sides of the trainer).

  10. Start the motor by pressing the black button on the side of the white box near to the reservoir, then rotate the control valve (silver arm) to let the flow move through the circuit.

  11. By shifting the directional control valve, the piston should extend and retract.

  12. By controlling the knob on the one-way restrictor valve, the retraction speed should change.

  13. Fully open the one-way restrictor valve (setting 10) and record the pressure from all the gauges, the flow rate, and the time of extension and retraction in the table below

  14. Change the opening of the one-way restrictor valve and record the pressure from all pressure gauges, the flow rate, and the time of extension and retraction in the table. Repeat this step two times.

  15. Take a picture for the circuit and insert it into your report.

  16. Comment on the data you collected

Activity #2: Construct Meter-Out Circuit

• Equipment: Bosch Rexroth hydraulic trainer.

• Procedure:

  1. Before starting the experiment, listen to the instructor’s description of the circuit and Follow the safety checklist.

  2. Start the circuit by placing the required components on the trainer.

  3. Connect a hose from the pressure port on the connection header “port P” to the “P” port of the directional control valve.

  4. From port “B” on the DCV to port “B” on the one-way restrictor valve.

  5. From port “A” on the one-way restrictor valve to the rod end of the cylinder.

  6. From the blank end of the cylinder connect a hose to port “A” on the DCV.

  7. Install four pressure gauges in the circuit: before and after the one-way restrictor valve, near the blank end, and at the connection header to measure the circuit pressure.

  8. Install a flowmeter whether before or after the one-way restrictor valve.

  9. Pull out the red safety switch (make sure it is pulled out from both sides of the trainer).

  10. Start the motor by pressing the black button on the side of the white box near to the reservoir, then rotate the control valve (silver arm) to let the flow move through the circuit.

  11. By shifting the directional control valve, the piston should extend and retract.

  12. By controlling the knob on the one-way restrictor valve, the retraction speed should change.

  13. Fully open the one-way restrictor valve (setting 10) and record the pressure from all the gauges, the flow rate, and the time of extension and retraction in the table below

  14. Change the opening of the one-way restrictor valve and record the pressure from all pressure gauges, the flow rate, and the time of extension and retraction in the table. Repeat this step two times.

  15. Take a picture for the circuit and insert it into your report.

  16. Comment on the data you collected.

  17. Remove the hoses from the horizontal cylinder on the trainer and connect it to the vertical cylinder located beside the trainer.

Activity #3: Construct and Simulate A Meter-In or Meter-Out Circuit On Automation Studio

• Equipment: A computer with Automation Studio software

• Procedure:

  1. Start Automation Studio and build either a Meter-in or Meter-out circuit.

  2. After completing the circuit design, simulate the circuit.

  3. Change the opening of the needle valve of the one-way restrictor valve. Observe the extension and retraction speed.

  4. Save a print screen of your circuit and insert a copy in your report.

Post Lab Questions

1. In the Meter-out extension, why did the pressure increase at the rod end? What is the name of this phenomenon?

2. What are the applications (in industry) when you should Meter-out circuit and Meter in Circuit? (Provide real applications).

3. Using ANSI symbols, draw the following circuits (all details should be included):

   • Meter-in Extension

   • Meter-out Retraction

Advanced Hydraulics: Pressure Control Valves

Objectives

• Understanding the difference between different pressure control valves.

• Understanding the function of pressure reducing circuit, counterbalancing a hydraulic motor circuit, and sequencing a motor and a cylinder circuit.

• Being able to build and design hydraulic circuits on Automation Studio.

Background and Theory

• Valves in fluid power systems are used to control the direction, flow, and pressure.

• Three different pressure control valves will be used in different circuits:

  • Pressure reducing valve.

  • Counterbalance valve.

  • Sequence valve.

  • Brief description of each valve will be introduced before building the circuit on the trainer in addition to the pressure relief valve.

Pressure Relief Valves

• Most widely used type of pressure control valve since it is found in practically every hydraulic system.

• It is a normally closed valve whose function is to limit the pressure to a specified maximum value (cracking pressure) by diverting the pump flow back to the tank to prevent the damage of any component in the hydraulic circuit.

• Performed by sensing the pressure before the valve (upstream pressure).

Pressure-Reducing Valves

• Normally open valve used to maintain reduced pressures in specified locations of hydraulic systems lower than the pressure set by the pressure relief valve.

• Actuated by downstream pressure (after the valve) and tends to close as this pressure reaches the valve setting.

Sequence Valves

• Designed to cause a hydraulic system to operate in a pressure sequence.

• There are two outlet ports and one inlet port to the sequence valve in addition to a pilot control line at the bottom of the valve.

• Fluid flows through the lower outlet until its operation is completed.

• The pressure at the inlet will increase which is connected through the bottom port (pilot control to push the plunger up and let the fluid flow through the upper outlet port while blocking the lower outlet port.

• ANSI symbol of the sequence valve is similar to the pressure relief valve.

Counterbalance Valves

• Used to control the actuator (cylinder or motor) by means of sensing the pressure as pilot control at two different points in the circuit.

• Used to maintain control of a vertical cylinder to prevent it from descending due to gravity.

• Can be used with hydraulic motors (overrunning load) and are then commonly called a brake valve.

Experiments Setup and Procedure

• Four activities will be conducted in this laboratory:

  • Construct a pressure reducing circuit on the hydraulic trainer.

  • Construct counterbalancing a hydraulic motor circuit on the hydraulic trainer.

  • Construct sequencing a motor and a cylinder circuit on the hydraulic trainer.

  • Construct and simulate any of the above circuits on Automation studio.

Activity #1: Construct Pressure Reducing Circuit

• Equipment: Bosch Rexroth hydraulic trainer.

• Procedure:

  1. Before starting the experiment, listen to the instructor’s description of the circuit and Follow the safety checklist.

  2. Start the circuit by placing the required components on the trainer.

  3. Connect a hose from the pressure port on the connection header “port P” to the “P” port of the directional control valve.

  4. From port “A” on the DCV to the inlet of the flowmeter, then from the outlet of the flowmeter to the inlet of the pressure reducing valve.

  5. From the exit of the pressure reducing valve to the blank end port on the cylinder. Install a pressure gauge before the blank end port. [Install a pressure gauge on the connection header to measure the system pressure].

  6. Connect a hose from the rod end port on the cylinder to port “B” on the DCV.

  7. Pull out the red safety switch (make sure it is pulled out from both sides of the trainer).

  8. Start the motor by pressing the black button on the side of the white box near to the reservoir, then rotate the control valve (silver arm) to let the flow move through the circuit.

  9. By shifting the directional control valve, the piston should extend and retract.

  10. By controlling the knob on the pressure reducing valve, the pressure reading on the pressure gauge would change.

  11. Fully open the pressure reducing valve and record the pressure and the flow rate, and the time of extension and retraction in the table below

  12. Change the opening of the pressure reducing valve and record the pressure and the flow rate, and the time of extension and retraction in the table below. Repeat this step two times.

  13. Take a picture for the circuit and insert it into your report.

  14. Comment on the data you collected

Activity #2: Construct Counterbalancing a Hydraulic Motor Circuit

• Equipment: Bosch Rexroth Trainer.

• Procedure:

  1. Before starting the experiment, listen to the instructor description of the circuit and Follow the safety check list.

  2. Start the circuit by placing the required components on the trainer.

  3. Connect a hose from the pressure port on the connection header “port P” to the “P” port of directional valve.

  4. Connect a hose from port “A” on the DCV to the inlet of the motor. Install a pressure gauge at the inlet of the motor. [Install a pressure gauge on the connection header to measure the system pressure].

  5. Connect a hose from the exit of the motor to the inlet of the counterbalance valve and install a pressure gauge between the motor and the valve.

  6. Connect a hose from the exit of the counterbalancing valve to the inlet of the flow meter then from the outlet of the flow meter to port B on the DCV.

  7. Pull out the red safety switch (make sure it is pulled out from both sides of the trainer).

  8. Start the motor by pressing the black button on the side of the white box near to the reservoir, then rotate the control valve (silver arm) to let the flow move through the circuit.

  9. By shifting the directional control valve, the motor will rotate.

  10. By controlling the knob on the counterbalance valve, the speed of the motor will change

  11. Open the counterbalance valve to a certain opening and record the pressure and the flow rate, and the speed of the motor using a tachometer in the table below.

  12. Change the opening of the counterbalance valve and record the pressure and the flow rate, and the speed of the motor in the table. Repeat this step two times.

  13. Take a picture for the circuit and insert it in your report.

  14. Comment on the data you collected.

Activity #3: Construct Sequencing A Motor and A Cylinder Circuit

• Equipment: Bosch Rexroth hydraulic trainer.

• Procedure:

  1. Before starting the experiment, listen to the instructor’s description of the circuit and Follow the safety checklist.

  2. Start the circuit by placing the required components on the trainer.

  3. Connect a hose from the pressure port on the connection header “port P” to the “P” port of the directional control valve.

  4. Connect two multi-port connectors to port “A” and port “B” on the DCV.

  5. Connect a hose from one of the ports on the multiport connector at port “A” on the DCV to the blank end port on the cylinder

  6. Connect a hose from one of the ports on the multiport connector at port “B” on the DCV to the rod end port on the cylinder.

  7. Connect a hose from one of the ports on the multiport connector at port “A” on the DCV to the inlet of the sequence valve.

  8. Connect a hose from the exit of the sequence valve to the inlet of the motor.

  9. Connect a hose from one of the ports on the multiport connector at port “B” on the DCV to the outlet port of the motor.

  10. Pull out the red safety switch (make sure it is pulled out from both sides of the trainer).

  11. Start the motor by pressing the black button on the side of the white box near to the reservoir, then rotate the control valve (silver arm) to let the flow move through the circuit.

  12. Observe the function of the circuit as the directional control valve is controlled.

  13. Control the knob of the sequence valve and observe how the circuit works.

  14. Take a picture for the circuit and insert it into your report.

Activity #4: Construct and Simulate Any of The Above Circuits on Automation Studio

• Equipment: A computer with Automation Studio software.

• Procedure:

  1. Start Automation Studio and build any of the previous circuits.

  2. After completing the circuit design, simulate the circuit.

  3. Save a print screen of your circuit and insert a copy in your report.

Post Lab Questions

1. What is the function of a pressure reducing valve?

2. Is a bypass check valve always required when using a pressure reducing valve in this type of circuit? Explain your answer in detail.

3. What is the function of a counterbalance valve in the hydraulic motor circuit? Explain your answer in detail

4. In the sequencing circuit, if the cylinder diameter is 2 in, the rod diameter is 0.5 in, and the stroke is 12 in. The cylinder was used to lift a load of 2500 lb, what should be the pressure setting of the sequence valve.

5. Give real application examples of sequencing operation between cylinder and motor.

Pneumatic Circuits I

Objectives

• Being familiar with different pneumatic components used to construct circuits.

• Building simple pneumatic circuits using the pneumatic components.

• Being able to build and design pneumatic circuits on Automation Studio.

Background and Theory

• Pneumatic systems use air as the gas medium because air is very abundant and can be readily exhausted into the atmosphere after completing its assigned task.

• Pneumatic systems are considered in many industrial applications instead of hydraulic systems due to the low weight of air in comparison to liquids, lower force to compress air, low viscosity, and lower cost in comparison to hydraulic systems.

• It is impossible to obtain precise, controlled actuator velocities or precise positioning control with pneumatic systems as these systems exhibit spongy characteristics due to the compressibility of air.

• The pneumatic components are similar to hydraulic components, but they are of lighter construction since pneumatic system pressures are lower compare to hydraulic.

• When analyzing or designing a pneumatic circuit, the following four important considerations must be taken into account:

  • Safety of operation.

  • Performance of desired function.

  • Efficiency of operation.

  • Costs.

Experiments Setup and Procedure

• Four activities will be conducted in this lab. Four different circuits will be constructed:

  • Remote operation of a single acting cylinder.

  • Two interlock safety circuits (AND circuit).

  • Direct operation from two locations using a shuttle valve (OR circuit).

  • In addition, one of these circuits will be built and simulated on Automation Studio.

Activity #1: Remote Operation of a Single Acting Cylinder

• Equipment: Bosch Rexroth pneumatic Trainer.

• Procedure:

  1. Before starting the experiment, listen to the instructor’s description of the circuit and follow the safety checklist.

  2. Start the compressor and set the pressure to 40 psi. [Air will not flow in the circuit unless the shut-off valve at the pressure regulator is opened. This will be opened when the circuit is completed].

  3. Start the circuit by placing the required components on the trainer in the right order.

  4. From the multiple-port air distributor, connect a tube to port “1” to the push-button 3/2 DCV. Also, connect a tube from the distributor to port “1” at the pneumatic-operated 3/2 DCV.

  5. Connect a tube from port “2” at the push button valve to the pneumatic pilot port “14” at the pneumatic operated valve.

  6. Connect a tube from port “2” at the pneumatic operated DCV to port “1” at the one-way restrictor valve.

  7. From port “2” at the one-way restrictor valve, connect a tube to the blank end on the single-acting cylinder.

  8. Set the pressure regulator to 40 psi and open the shut-off valve.

  9. Press the push button and observe the extension of the cylinder (it will retract by the force of the spring).

  10. By controlling the knob at the one-way restrictor valve, the speed of the extension will change.

  11. Take a picture for the circuit and insert it into your report.

Activity #2: Two Interlock Safety Circuits (AND Circuit)

• Equipment: Bosch Rexroth pneumatic trainer.

• A- Using Two Inline Valves

  1. Before starting the experiment, listen to the instructor’s description of the circuit and follow the safety checklist.

  2. Start the compressor and set the pressure to 40 psi.

  3. Start the circuit by placing the required components on the trainer in the right order.

  4. From the multiple-port air distributor, connect a tube to port “1” to the first push-button