CHAPTER ONE
1.0    INTRODUCTION
Door is a movable structure that is used as a means of closing off entrances for security purpose and also for the beautification of the area. In the ancient time, doors were not used and the people of then live comfortably in peace since there is trustworthiness among them, but as time goes on, some people gang up to become an enemy of progress, they started stealing another people’s properties and also terminate their live. This brings the people of those days to sit down and discover what is now known as door. During that time, doors were made of grasses or wood as a means of locking to secure their life and properties.
Wood as a material has a long history; it is the major component in the construction of doors. Doors made from wood is easy to construct and very cheap, but it can easily be destroyed when termites and other pests penetrate through it and it is not friendly with water and fire. The same thing happens to doors made from grasses, even worsen than that of the wooden door. As a result of these properties, wooden or grass door is not effective for security purpose as it can be easily breakthrough.
It was due to these problems that made engineers to develop and design more strong and effective door which is the metal door. Metal doors are in various design, these are: metal flush doors, flat sheet metal door etc.
The doors mentioned above give maximum protection to life and properties and meet people’s want.
But for more advancement, double panel door was employed by modern engineer into the family of existing doors to give maximum satisfaction. So the construction of this project is based on this double panel metal door. This door is divided into two (2) halves; the big door and the small door. It consists of the frame, the panel which is made of metal sheet, the stopper, the locking device, the hinges and the handle.
There are forces acting on door, these are: -
1.    Contact Force: - This is a force which exists between surfaces in contact. It includes pushing and pulling forces, frictional forces and tension force in strings and wires.
2.    Force Field: - Typical examples of force field include gravitational force, electrostatic force and magnetic force.
A gravitational force is the force which the earth exerts on every object on its surface.
1.1    Objectives of the Project
Some of the aims and objectives of this project are stated below:
i.    To prepare students for future task as an engineer or technologist.
ii.    To provide maximum security for life and properties.
iii.    To ensure better life span for door with the use of quality materials.
iv.    To promote and improve the method of door designs to a modern design.
v.    To allow large objects to pass through the door at the same time by opening the two (2) panels.
vi.    To expose the students to various machines used in the construction of twin panel metal door and to be technically involved.
1.2    The Need for Doors
The main reason and the need for doors include:
i.    For security purpose
ii.    To allow for privacy
iii.    For beautification of houses, offices, shops etc.
iv.    Regulation of access and noise reduction.
v.    To control the physical atmosphere within a space by enclosing the air drafts so that interiors may be more effectively heated or cooled.