Study Project ( describes a method to design a SPRING for the Mechanical Engineering )

Study Project Name
Project report submitted

In partial fulfilment of the requirement for the degree of

B-Tech (H)

In

Mechanical Engineering

By

Muhammad Safdar                                          Roll# Number 1603

Supervized by:

Engr. Mehran Waheed

DEPARTMENT OF MECHANICAL ENGINEERING

SUPERIOR COLLEGE SIALKOT

December 2016

Abstract

This report describes a method to design a SPRING for the Mechanical Engineering Department of Superior College Sialkot, Pakistan. The reason being selecting the study is that to facilitate the department to compensate the huge expenses of on-grid power supply and also load shedding. The appliances are calculated from the whole department and tabulated in a sequence according to time table and load profiles developed. The novelty of this project is that a model is developed that is able to calculate the entire required components of the photovoltaic system as according to our load requirement. In addition, the methods to determine the positioning of solar panels are also presented.

The project work includes:

·       Introduction of Spring

·       Discussing different use of spring and different kinds

·       History

Acknowledgement

We express our sincere thanks and deep sense of gratitude towards Engr. Mehran Waheed for his guidance from which we are able to implement this project from concept to design. His timely and incisive review, comments and suggestions throughout the project enabled us to modify the project before things went out of our hand. We thank him for everything, from conception of getting things done practically and a lot of steps along the way, which helped us in overcoming our difficulties and making the project a successful.

Also we are highly thankful to Company Sialkot, whose cooperation helped us to make our calculation more realistic.

Dedication

 This project is dedicated to our parents whose prayers blended in our hard work to produce this project. Without their support and utmost faith this would have never been possible. Also it is dedicated to Pak Army who is always ready to sacrifice for our homeland.

Further, it is dedicated to our teachers specially Engr. Mehran Waheed, who provided us with unmatched support whenever we tumbled.

The dedication would be incomplete if I do not mention the emotional support and blessings provided by our friends.

                                                                                            

____________________________

Muhammad Safdar (Roll No.1603)

Date: 18-December-2016

List of figures

Figure 2.1: Tension/extension spring ……………………………………………..04

Figure 2.2: Compression spring …………………………………………………..05

Figure 2.3: Torsion spring ……….……………………………………………….05

Figure 2.4: Constant spring ……..……………………………………………….06

Figure 2.5: Variable spring ……….……………………………………………….06

Figure 2.6: Coil spring ……….….……………………………………………….07

Figure 2.7: Flat spring ……….……………………….………………………….07

Figure 2.8: Machined spring .….……………………………………………….08

Figure 2.9: Coil spring or helical spring .……………………………………….08

Chapter 1

Introduction

1.1.      Introduction

Spring (device)

A spring is an elastic object used to store mechanical energy. Springs are usually made out of spring steel. There are a large number of spring designs; in everyday usage the term often refers to coil springs.

Small springs can be wound from pre-hardened stock, while larger ones are made from annealed steel and hardened after fabrication. Some non-ferrous metals are also used including phosphor bronze and titanium for parts requiring corrosion resistance and beryllium copper for springs carrying electrical current (because of its low electrical resistance).

When a coil spring is compressed or stretched slightly from rest, the force it exerts is approximately proportional to its change in length (this approximation breaks down for larger deflections). The rate or spring constant of a spring is the change in the force it exerts, divided by the change in deflection of the spring. That is, it is the gradient of the force versus deflection curve. An extension or compression spring has units of force divided by distance, for example lbf/in or N/m. Torsion springs have units of torque divided by angle, such as N•m/rad or ft•lbf/degree. The inverse of spring rate is compliance, that is: if a spring has a rate of 10 N/mm, it has a compliance of 0.1 mm/N. The stiffness (or rate) of springs in parallel is additive, as is the compliance of springs in series.

Depending on the design and required operating environment, any material can be used to construct a spring, so long as the material has the required combination of rigidity and elasticity: technically, a wooden bow is a form of spring.

1.2.      Our objective

·       Utilization of available designs at more effective ways.

·       To improve technologies for Mechanical engineering department.

·       To provide un interrupted and noise free machines.

·       To provide cost effective and environmental beneficial source of advance technology.

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Chapter 2

History and kinds

2.1.      Introduction kinds of spring and history

History, Simple non-coiled springs were used throughout human history, e.g. the bow (and arrow). In the Bronze Age more sophisticated spring devices were used, as shown by the spread of tweezers in many cultures. Ctesibius of Alexandria developed a method for making bronze with spring-like characteristics by producing an alloy of bronze with an increased proportion of tin, and then hardening it by hammering after it was cast. Coiled springs appeared early in the 15th century, in door locks. The first spring powered-clocks appeared in that century and evolved into the first large watches by the 16th century.
In 1676 British physicist Robert Hooke discovered Hooke's law which states that the force a spring exerts is proportional to its extension.

Types of springs, Springs can be classified depending on how the load force is applied to them:Tension/extension spring – the spring is designed to operate with a tension load, so the spring stretches as the load is applied to it.

Figure 2.1

Compression spring – is designed to operate with a compression load, so the spring gets shorter as the load is applied to it.

Figure 2.2

Torsion spring – unlike the above types in which the load is an axial force, the load applied to a torsion spring is a torque or twisting force, and the end of the spring rotates through an angle as the load is applied.

Figure 2.3

Constant spring - supported load will remain the same throughout deflection cycle

Figure 2.4

Variable spring - resistance of the coil to load varies during compression

Figure 2.5

They can also be classified based on their shape:

Coil spring – this type is made of a coil or helix of wire

Figure 2.6

Flat spring – this type is made of a flat or conical shaped piece of metal.

Figure 2.7

Machined spring – this type of spring is manufactured by machining bar stock with a lathe and/or milling operation rather than coiling wire. Since it is machined, the spring may incorporate features in addition to the elastic element. Machined springs can be made in the typical load cases of compression/extension, torsion, etc.

Figure 2.8

Coil spring or helical spring – a spring (made by winding a wire around a cylinder) and the conical spring. These are in turn of two types: Compression springs are designed to become shorter when loaded. Their turns (loops) are not touching in the unloaded position, and they need no attachment points. A volute spring is a compression spring in the form of a cone, designed so that under compression the coils are not forced against each other, thus permitting longer travel. Tension or extension springs are designed to become longer under load. Their turns (loops) are normally touching in the unloaded position, and they have a hook, eye or some other means of attachment at each end.

Figure 2.9

CONCLUSION AND REMARKS:

Science and technology is a growing field in Pakistan and has played an important role in the country's development since its founding. Pakistan has a large pool of scientists, engineers, doctors, and technicians assuming an active role in science and technology. Liaquat Ali Khan the first Prime Minister of Pakistan (in office 15 August 1947 – 16 October 1951), made various reforms to initiate improvement in higher education and scientific research.

This is spring technology is very important , if we get more advance devices the thing will be more and more effective , as we already seen these springs are being use in Vehicles: Vehicle suspension, Watches: Balance springs in mechanical timepieces and spring-loaded bars for attaching the bands and the clasps. Mini Drill, Jewelry: Clasp mechanisms. Lock mechanisms: Key-recognition and for coordinating the movements of various parts of the lock. Pop-open devices: CD players, Tape recorders etc. Pens, spring mattresses, Slinky, Trampoline , Pogo Stick, Spring reverb, Buckling spring keyboards, Upholstery: Upholstery coil springs, Toy, Educational, Airsoft gun, Firearms, cars

The mechanical engineering field requires an understanding of core areas including mechanics, kinematics, thermodynamics, materials science, structural analysis, and electricity. Mechanical engineers use these core principles along with tools like computer-aided design, and product lifecycle management to design and analyze manufacturing plants, industrial equipment and machinery, heating and cooling systems, transport systems, aircraft, watercraft, robotics, medical devices, weapons, and others.

References

1.     General Discussions with  Engr. Mehran Waheed

2.     http://custommadeitems.blogspot.com/

3.     https://en.wikipedia.org/wiki/Spring_(device)

4.