UNIVERSITI TEKNOLOGI MARAFAKULTI KEJURUTERAAN MEKANIKAL

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Program : Bachelor of Engineering (Hons) Mechanical (EM221)Course : Robotic and Automation Course Code : MEM 665Lecturer : Dr. Low Cheng Yee___________________________________________________________________________

Laboratory Report

HYDRAULIC LABOTARY CONVEYOR TENSIONING DEVICE

No.

Name Student ID Number Signature

1. MOHD SHAHIR BIN ABDULLAH 2008289642

2. MOHD AKMAL BIN SHAFIE 2008515075

3. KHAIRIL HAZRIQ BIN MAT ISMAIL 2007127791

4. MUHD ANAS BIN MOHAMMED 2008501277

Practical Session : __03/03/2010 Staff certification : ________________ (Date) (Signature)

Report Submission : _ 22/03/2010 Staff certification : ________________ (Date) (Signature)

1.0 OBJECTIVES:

1- To assemble, test, troubleshoot (if necessary) and describe the

operation of hydraulic cylinder in tension, retraction and stop position.

2- To familiarize the student with the applications of a 4/3-way valve and

show how to use a piloted non-return valve.

3- To design and propose a new improvement of the existing system.

EXPERIMENT 1

2.0 INTRODUCTION

The basic idea behind any hydraulic system is very simple: Force that is applied at one

point is transmitted to another point using an incompressible fluid. The fluid is almost

always an oil of some sort. The force is almost always multiplied in the process.

A hydraulic system circulates the same fluid repeatedly from a fixed reservoir that is

part of the prime mover. The fluid is an almost non-compressible liquid, so the actuators

it drives can be controlled to very accurate positions, speeds, or forces. Most hydraulic

systems use mineral oil for the operating media but other fluids such as water, ethylene

glycol, or synthetic types are not uncommon. Hydraulic systems usually have a

dedicated power unit for each machine. These hydraulic systems operate more like a

compressed-air installation because the power source is in one location.

3.0 LITERATURE REVIEW AND THEORY:

Parts are fed through a drying oven on a steel chain conveyor belt. It must be possible to

correct the tracking of the belt means of a tensioning device to ensure that the belt does

not run off its rollers. This device consists of a steel roller fixed at one end kind movable

at the other by means of a double-acting cylinder. Hydraulic power must be available

continuously. The hydraulic system must switch to the recirculation (pump bypass)

condition counter force to act on the cylinder. A piloted non-return valve is used to

prevent creep age of the piston rod of the positioning cylinder as a result of oil leakage

losses in the directional control valve.

Figure 1: a drying oven on a steel chain conveyor belt system

4.0 PROCEDURE:

1. The drawing of the given hydraulic circuit diagram of the system was studied and

understood.

2. The hydraulic components that were involved in this experiment were

recognized and familiarized through their symbol labels.

3. The practical assembly of the hydraulic circuit was constructed.

4. The system was executed by pressing and activating the switch involved.

5. Observations and results were obtained.

Hydraulic circuit for above system

5.0 RESULTS :

Figure 1: Complete circuit (cylinder is retracts)

CYLINDER IN RETRACT POSITION

PRESSURE INPUT

TANK OUTPUT

PIPE/HOSE

JOINT

CYLINDER

Figure 2: Complete circuit (cylinder is extended)

CYLINDER IN EXTENDS POSITION

4/3 WAY VALVE

CHECK VALVE

4/3 WAY VALVE

POWER SWITCH

CYLINDER

HYDRAULIC COMPONENTS

NO FIGURE DESCRIPTION

(a)

Check valve

Allows fluid to flow in one direction, in this case from bottom to top.

(b)

4/3-way valve manually

These valves have four or five pipe connections, commonly called ports. One pressure inlet, two cylinder ports providing pressure to the double acting cylinder or actuator and one or two outlets to exhaust pressure from the cylinders.

(c)

Butterfly valve

Butterfly valves are used for applications when a short layout length is desirable and the valve is not used for precise flow regulation. 

(d &e)

Pressure relief valve

Are quick-opening, quick-closing valves used to protect equipment from gas pressure build up or pressure surges. 

(f)

Pump

To move liquid by pressure or suction. Hydraulic pumps are used to transfer energy and are powered by an energy source that initializes the pump but has no part in the pumping action itself.

(g)

Motor

Hydraulic motors convert hydraulic energy into mechanical energy. A pump is connected via a carrier line to a motor, which then draws fluid from a reservoir and forces it into the motor. The fluid forces the movable components of the motor into motion, which in turn rotates the attached shaft. The shaft, which is mechanically linked to the work load, provides rotary mechanical motion.

(h)

Cylinder

Retract or extend to ensure that the fluid flow with the right system.

6.0 APPLICATIONS:

The typical applications of hydraulic system are:

In tools purposes;

1. Hydraulic jack

2. Hydraulic puller

3. Hydraulic lifter

4. Hydraulic rock crushing

5. Hydraulic metal cutter

In vehicle and transportation purposes;

1. Snow Plow (Hydraulics raises blade)

2. Tow Truck (Hydraulics raises boom)

3. Cherry Pickers (Hydraulics raises arm)

4. Marine Winch Drive (Hydraulics run winch)

5. Aircraft (Hydraulic run landing gear)

6. Backhoe (Hydraulic raises boom)

7. Automotive (Hydraulic run steering and breaking system)

In industry purposes;

1. Stamping Machine (Hydraulic raises die ram)

2. Punching and blanking machine (Hydraulic raises tool edge)

3. CNC Milling machine (Hydraulic control spindle movement)

4. Extrusion Machine (Hydraulic squeeze metal billet to the die)

7.0 RECOMMENDATIONS (improvement):

To improve hydraulic system first we need to know weaknesses of this system, here we

have some weaknesses of the hydraulic system and recommendation ways to overcome

this weaknesses:

Weaknesses of hydraulic system Improvement

Working fluid leak from the

system (messy) Use high pressure sealant

Hydraulic system over heating

(can effect sealant bonding)

Use heat sink to dissipated heat

from the working fluid

Need period maintenance Use hydraulic system wisely

Noisy system Use low noise motor

8.0 SUMMARY:

As a conclusion we had achieved our objective to assemble, test, troubleshoot and

describe the operation of hydraulic cylinder in tension, retraction and stopped position,

to familiarize the student with the applications of a 4/3-way valve and show how to use

a piloted non-return valve and to design and propose a new improvement of the existing

system.

The hydraulic system we construct was successful because the cylinder is able to retract

and extend. Figure 1 & 2 shows that the mechanism used in the hydraulic system for

hydraulic laboratory conveyor tensioning device which is 4/3-way valve, check valve,

pump, motor, reservoir, hose and etc. Figure 3 shows that schematic diagram of the

hydraulic system that has been labeled for each component.

In completing the experiment, we faced many problems that required reference from

the technician, but we managed to complete our experiment successfully. One of such

problem is as the following; the valve is in a pressurized condition and as a result, we

cannot assemble the hose to the valve. Finally, we were able to complete the circuit by

the help from technician and lecturer. Another problem is that the components to be

assembled at the circuit board were not stored and labeled properly. Therefore, we went

through the difficulties in finding the components in the drawer. In addition, while

operating the circuit, the oily components also influenced our experiment.

As recommendations, the lab should provide a way to clean and maintain the

components and provide extra technician to guide us while conducting the experiment.

Hydraulic machines are machines and tools which use fluid power to do work. Hydraulic

systems have a quite high power density, and this makes hydraulic systems and

machinery widely applied in various fields and industries. Heavy equipment is a

common example.

In this type of machine, high pressure hydraulic fluid is transmitted throughout the

machine to various hydraulic motors and hydraulic cylinders. The fluid is controlled

directly or automatically by control valves and distributed through hoses and tubes.

9.0 REFERENCE

1. http://en.wikipedia.org/wiki/Electrohydraulic_manual_transmission

2. http://material-handling.globalspec.com/LearnMore/Flow_Transfer_Control/

Valve_Actuators_Positioners/Hydraulic_Electrohydraulic_Valve_Actuators

3. http://en.wikipedia.org/wiki/Hydraulic_system

4. http://www.hydraulicspneumatics.com