LAB#7A
Theory and Operation
1. Black Direct Acting Pressure Relief Valve
This lab is used to analyze the action of various values by disassembling and assembling. This valve is used to describe its action in the hydraulic circuits.
Action of Black Direct Acting Pressure Release Value
The relief valve acts as the fuse or circuit breaker in an electric circuit. An electric circuit blows a fuse unless it overloads. The hydraulic circuits allow the relief value to dump. Protecting the pump from the excess pressure is the main function of a relief valve. The direct acting relief value responds quickly to the pressure tries to go and observe the valve settings. It is used to reduce the pressure spikes. On hydraulic circuit the direct acting relief valve opens partially and releases energy. This type of relief value is used in the steam locomotive.
2. Disassemble of Pilot Operated Pressure Relief Valve
This type of relief valve has two sections. The pilot operated relief valve is at top; poppet type direct acting relief valve. The main section of the valve is poppet or piston type. A pilot operated relief valve responds slowly. A pilot operated relief valve is suitable for the remote operations. This type of valve is used for the remote operations.
3. Disassemble of color flow control Valve
The F Flow control valves have a precise control of flow and permits the full flow in the opposite direction. The two- step needle has a fine adjustment at the low flow using first three turns of the adjusting knob. The next turn open the valve to full flow. The main operating pressure is 140 PSI.
The pressure compensated flow control values works accordance with the DIN – ISO 1219, values for the oil hydraulic systems. The hydraulic systems maintain constant outlet flow means of the control functions. The flow valve is largely depends on the pressure viscosity. It has the main advantage of the space saving installation and compact construction. Fitting of control blocks and choice of size ensures the possible adaptability. The main advantage of this value is saving the space of the installations.
The air pressure regulator works automatically. It has a control element to ensure the downstream element the pressure doesn’t exceed the set point. It has a safety device to protect the equipment harmful to overpressure. The flow system can operate safely and effectively. A pressure regulator is an open value takes high inlet pressure. The advantage lies in the fact that the greater accuracy and repeatability was achieved via spring. Overall design has the large sensing area. This all combined to provide best performing.
5. Disassemble of Norgren Air Flow Regulator Valve
The control valve is operated by the actuators. There are two types of control valve; it is air open and air close type. If the air supply fails, the control valve is either will be fully opened or fully closed. If valve is used to control steam, the valve shut off completely in air failure. On the other hand the valve is handling cooling water to the reactor.
6. Results and Analysis
1. Measure the diameter of the winch drum on the motor and calculate the maximum torque output for this motor for each weight.
T= VoP/2Tr
T = 0.0633
3. Calculate motor displacement from the data obtained. Motor displacement per revolution may be obtained by dividing volume of oil by the number of motor revolutions. One quart volume = 57.75 cubic inches.
Volume of oil = 57.75 cubic inches.
Motor Displacement = 96.75/57.75 = 1.6753247
4. If the motor normally supplied has a displacement per revolution different than you Just calculated. Explain the difference.
The difference is due to the leak, head loss, and fiction. All the analysis will not give perfect results due to some loss in the system.
5. Based on experimental results, what flow would be required to operate the motor f
At its maximum rated speed of 3750 RPM?
3000 PSI is required to operate the motor in the required RPM. The 3000 PSI is required to operate the motor in 3750 RPM.
6. Attempt to rotate the shaft with the control valve in the neutral position. Explain why
The motor offers high resistance to rotation.
The motor offers high resistance to rotation due to the fiction and wind opposition loss. The fiction loss of the shaft offers high resistance to the rotation. This loss is stable and it can be reduced to some extent, but it cannot be removed.
7. A hydraulic pump driving a hydraulic motor is frequently used as a means of power transmission. Name several advantages it may have over a mechanical transmission.
It is a good energy efficient system. It is depending on the drive concepts. The hydraulic drive takes up an average of 48% of machine total energy consumption. Volume of pump bled out a relief valves, which generates the frictional heat in the oil. Some drive pump significantly saves the energy up to 35% compared to the other convectional drives. This kind of drives contributes to the larger service life for the machine hydraulic oil.
8. Name the three most common types of hydraulic motors.
Gear and Vane motors, Gerotor motors, and axial plunger with radial piston motors are the three most common types of motor.
Conclusion
The complete working and function of the control valve is analyzed in this paper. Each valve has unique characteristics. The ANSI picture for each valve is shown in the picture. The readings are taken; the analyses are made based on the reading.
