The idea of using fence and gates in Nigeria is not new, however, only a few actually practice it because of its capital consumption. Though the majority now use it for prestige and show of status, the benefits of using fence and gates cannot be overemphasized.
In Nigeria, many investors that buy virgin lands usually use block fence and steel gate to secure their boundaries to avoid intrusion in their land in the future since land dispute has been found to be a major source of most community crisis, court cases, quarrels, and family fights, etc. within the country.
Modern gates have gone beyond the design of putting just steel plates together to something unique with the combination of aesthetic and structural integrity in the mind of structural engineers. Though simple gates exist and the majority of the design can be produced by street welders in Nigeria.
The star-guard sliding gate can be used in private or public buildings. It is a gate designed with simplicity and reliability of operation in the mind of the engineers. For the purpose of the smooth operation, the gate has the feature of light-weight and flexibility for sliding operations in order to ensure that the electric motor used in its opening and closing experiences less stress.
The model illustrated using a diagram in this post has no actual size specifications except for the standard gate sizes being used in modern Nigeria buildings. In terms of request for production, the gates can be made with any size while maintaining the same design. The modern steel gates in Nigeria could be either 12feet length, 10feet length, or 8feet length. The height of all of them remains the same i.e. 4feet to 5feet. Any other design of sliding gate can be produced while maintaining the same standard and principle of operation of this design.
Below are the general features of the star-guard design steel gates:
THE STAR-GUARD UNIT “A”
The name “star-guard” came from the attached reflective steel guard located at the top of the steel plates after its closing of an angle bar. The “A” symbol is an indication of the star-guard in the labeled diagram of the gate design. The star-guard could be fabricated, cast, or formed using a systematic machine operation. The major function is to ensure the top of the gate has pointed sharp edges making it impossible for bandits to climb the gate for any attempt of entering into the building or prevent unnecessary abuse of the security system of the fence by trying to jump over the fence. Therefore, the design will ensure the gate is secured against any abuse.
THE STEEL PLATE SECTION “B” AND “F”
The “B” inscription is the steel plate section of the gate. It forms the major part of the gate because it is the part that carries other parts. It can be made of any thickness based on client’s request. Some designs could be made with double plates for special protection such as “bullet-proof”. The type of steel plate (stainless or mild steel), thickness, and size of the gate will have a great influence on the cost of production. At the four edges of the steel plate, i.e “B” section angle bars or square pipes with significant thickness could be used to frame the section for the purpose of rigidity and strength. The thickness of any of the framing steel used also determines the overall weight, strength, and durability of the gate.
THE DOOR SECTION OF THE GATE “C” AND “I”
The “C” inscription is the “door” section of the gate. It measures 2 ½ feet to 3 feet in width and 6 feet in height. Designed with special arc made with a half-ellipse shape to join the top section together. A clearance of about 20 millimeters exists between the door and its frame and they are joined together with two long flexible hinges. The frame of the door can be strengthened with angle bar or square pipes with significant thickness. The next part that can be found in the door section is the “opening and closing handles” this part forms the “I” inscription. It helps the users to hold the door firmly during opening and closing operations. The location where the handles are found in the same location that the locking units can be fixed for easy operation.
THE MAIN GATE LOCKING UNIT “D” AND “E”
The main gate locking unit is the “D” & “E” inscription letters. The unit is made up of two thick iron angle bars the side of the D has the angle bar welded to the frame of the steel plate ‘B’ at the edge. The E side has inbuilt electromagnetic system attached to it. The function of the electromagnets is to magnetize the iron bar so that it can hold the D angle bar iron firmly thereby creating strong security and locking of the main gate. Once the magnet is ON the two iron angle bars are magnetized together making it impossible for anyone to open the gate except they are demagnetized by turning the voltage supply OFF. For the smooth operation of the automatic system, the electromagnetic locking system is synchronized with the electric motor located at “J” such that once the signal to open the gate comes in, the control unit cuts off the voltage supply going to the electromagnets at the locking unit before turning the voltage supply of the electric motor at “J” ON. For manual operations, the unit has three holes created for padlocks or direct cross-locking with steel rods.
THE MAIN GTE OPENING UNIT “J”
The main gate opening unit is made up with an electric motor “J” anchored in a way that it can drive the linear gear arrangement attached at the upper section of the steel plate backside. The electric motor has its own shaft “K” meant for transmission of motion. For that reason, the shaft “K” is made with uniform gear teeth which is directly proportional to that of the steel square “L”. The linear gear “L” is made with steel square bar with significant thickness machined to create uniform gear teeth for easy transfer of motor.
THE ROLLING/SLIDING UNIT “G” AND “H”
The rolling or sliding unit is a simple but carefully designed unit. It consists of the “G” and “H” inscription. The G part is made up of two rollers made with high carbon steel and thermos-treated to withstand high compressive stress coming from the weight of the gate and its sliding actions. The roller could be in any diameter and thickness based on the calculations obtained from the overall weight of the gate. The rollers have ball bearing attachment at each joint with the gate for easy rolling. The H unit is an external unit because it is fixed on the floor and has no direct joint with the gate though it is still part of the gate. The function of the H unit is to provide a suitable surface that the rollers could slide for easy opening and closing of the gate. It can be fixed on the floor using concrete or bolt and nuts system or the combination of both.
THE AUTOMATION UNIT “M”
The automation unit “M” is where the whole automatic control occurs. The unit is a small control box having an electric circuit inside it, it switches the electric motor on and off according to either timing or signal received. The closing and opening operations depend on the accuracy and sensitivity of the automation unit. It could be located either inside the building or beside the gate based on the client’s preferences.
THE COST OF PRODUCTION
In terms of cost, building this type of gate in Nigeria and its installation will cost from N400,000 to N1,000,000 depending on the size, quality, and special features.
Special features associated with the gate design are:
- Timed opening and closing operations
- Sensor controlled operations
- Alarm system for opening and closing
- Electrocution effect for security bridge control
- And other possible features.
DISADVANTAGES OF THE SLIDING GATE
- Because it works with the electromagnetic system for its automatic locking and opening, it will be suitable a place with a steady power supply or special inverter for the small gates.
- The rolling unit will need at least weekly cleaning and lubrication to ensure sand and trapped materials will not hinder the movement.
- The electromagnets could be a source for higher electricity consumption.
- The gear units need constant lubrication and inspection.
ADVANTAGES OF THE SLIDING GATE
- It is reliable in operation
- It could operate without a gateman
- It has a higher level of security than other types
- Very suitable for less busy areas that require a high-level security system
- It operates with less noise
