Design And Construction Of An Arc Welding Machine
The design and construction of an arc welding machine involve the intricate amalgamation of various components and processes, converging to form a sophisticated apparatus essential for joining metal components. At its core, an arc welding machine operates by generating an electric arc between the welding electrode and the workpiece, creating the intense heat required for fusion. The apparatus comprises a power source, typically an electric transformer, responsible for converting and regulating the input voltage to meet the specific welding requirements. Additionally, the machine incorporates a welding electrode holder, which securely grasps the electrode and facilitates its controlled movement. The inclusion of a protective shielding gas, often achieved through the use of flux or inert gases, shields the weld pool from atmospheric contamination, ensuring the integrity of the final weld. The meticulous construction of an arc welding machine involves precision in assembling these integral components, aligning them seamlessly to guarantee the machine’s efficacy in providing a stable and controlled welding process.
The machine is designed to serve with an output of 250A. it has two pats which are the primary and secondary parts. The primary part, through which voltage is supplied to the machine has 180 turns which is made of 2mm2 S.W.G 14 copper coil. The secondary part has 45 turns made of 4mm2 S.W.G 8 copper coil.
Both turns are wound on separate limb of the laminated core. The voltage from primary turns flows to the secondary turn by induction.
The machine contain a power switch through which the machine can be switched on or off when connected to the power source. The indication light simply shows when the machine is on or off which is equally controlled by the power switch.
The fan connected to the machine helps in the looking of the temperature of the machine, it gets started once the machine is on.
The welding current is adjusted by varying the spacing between the primary and secondary windings when the cranks is rotated, clockwise the insulating block between the two winding moves down, the magnetic flux leakage and the inductive impedance are increased, thereby reducing the welding current in the secondary windings. Also as the insulating block is moved upward, away between the two turns, the magnetic flux leakage and the inductive impedance are brought down, causing the welding current to rise.
Title Page/Approval Page
Certification
Dedication
Acknowledgement
Abstract
Table Of Content
Chapter One
1.0 Introduction
1.1 Aims/Objective
1.2 Scope Or Limitation
1.3 Definition Of Terms
Chapter Two
2.0 Literature Review
2.1 Transformer Design
2.2 Coil Design
2.3 Core Design
2.4 Equivalent Circuit Of The Machine
2.5 Machine Design
2.6 Operation Of Machine
2.7 Leakage Flux Reduction
2.8 Specification From Design
Chapter Three
3.0 Construction
3.1 Lamination
3.2 Transformer Former
3.3 Copper Coil
3.4 Insulating Materials
3.5 Methodology
3.6 Casing
3.7 Coupling
3.8 Electrical Holder
Chapter Four
4.0 Testing And Finding
4.1 Open-Circuit Test
4.2 Short-Circuit Test
4.3 Test Analysis
4.4 Conditions For Operation
4.5 Cost Analysis
Chapter Five
5.0 Conclusion
5.1 Recommendation
References
1.0 INTRODUCTION
The Arc welding machine is the type that uses an electric power as an input, which is being supplied through the primary and then transferred to the secondary winding by induction which can the be used to carry out welding work by connecting to the output terminal the welding cables.
The output of the machine is designed in a way that it can be varied by adjusting the crank of the machines in clockwise or anti-clockwise direction in either to increase or decrease the output current respectively depending on the size of the material it is to be used on.
AIMS/OBJECTIVES
This group agreed in bringing ideals together as one body to construct a functional 250Amp Arc welding machine, which will be fir in both industrial and agricultural field.
The machine takes an input ranging from 220volt to 230volts which will be induced to the secondary windings then giving out it’s output towards the output terminals of the secondary windings.
Due to the variation on the size of the metallic materials, the machine the machine is designed in such a way that it’s output current can be varied in other to suit the material it works one.
1.2 SCOPE OR LIMITATION
The machine is designed to be supplied with an input ranging from 220volts to 240volts. It is a single phase machine which gives it’s output through the output terminal of it’s secondary windings. The machine with it’s maximum output as 250Amps can be re-adjusted to a lower value when such output is considered too high.
He machine is equally designed to work with electrodes with their gauge ranging from 8,10 and 12 depending on the nature of the material and in all cases, it is expected to serve continuously for about 48hours provided the required input voltage is being supplied to it.
1.3 DEFINITION OF TERMS
Listed below are the definition of some of the term used in this project:
1.3.1 Coil: This is a copper conductor used to form the primary and secondary windings from which current enters and leaves out of the transformer.
1.3.2 Insulator: This can be defined as those materials that do not allow the passage of electric current through them. They are used to insulate the windings from each other as well as the laminated core.
1.3.3 Windings: This is the copper wire used as the coil, which is then wound on the limb of the laminated core from which current enters and leaves the circuit.
1.3.4 Flux: This can be defined as the magnetic effect experienced in the circuit due to the flow of current in the windings.
1.3.5 Laminated core: This is the core lamination which is inform of strips joined in such a way that the joints in the alternate layers are staggered in such a way as to avoid the presence of narrow gaps right through the cross-section of the core. It is constructed with transformer sheet steel lamination assembled to provide a continuous magnetic path. It consists of the joke and the limb which are equally laminated to reduce the lost due to eddy current.
1.3.6 Limb: This can be defined as the vertical parts of the lamination core on which the primary and secondary windings are wound separately on the different limbs of the laminated core
1.3.7 Yoke: This is the outer horizontal parts of the lamination core, which help in the reduction of eddy current losses, as well as provide mechanical support to the windings. It also carries the magnetic flux produced by the poles.
Design And Construction Of An Arc Welding Machine:
Components of an Arc Welding Machine:
- Power Source: The heart of an arc welding machine is its power source, which converts electrical energy into welding current. Most welding machines use either a transformer-based or inverter-based power source. Inverter-based machines are more compact and efficient.
- Control Circuit: A control circuit is needed to regulate the welding current, voltage, and other parameters. This typically includes components like potentiometers, switches, and electronic circuitry for precise control.
- Welding Electrode Holder: This is a clamp that holds the welding electrode (stick electrode) and provides a path for the welding current to flow from the machine to the workpiece.
- Work Clamp: Also known as the ground clamp, this is connected to the workpiece to complete the electrical circuit.
- Cooling System: High-power welding machines may require a cooling system to dissipate heat generated during welding.
Steps for Construction:
- Design Phase: Begin by designing the electrical and mechanical components of your welding machine. This includes selecting the power source, control circuitry, and safety features.
- Select Materials: Choose the materials for the machine’s casing, handles, and internal components. Ensure that they are durable and can handle the heat generated during welding.
- Assemble the Power Source: Depending on whether you are using a transformer-based or inverter-based power source, assemble and connect the necessary components. This may include transformers, diodes, capacitors, and inverter circuits.
- Control Circuitry: Design and assemble the control circuitry to regulate the welding current, voltage, and other parameters. Ensure safety features like overload protection and emergency shut-off are included.
- Safety Measures: Implement safety features such as thermal protection, short circuit protection, and safety interlocks to prevent accidents.
- Cooling System (if needed): If your welding machine operates at high power levels, consider implementing a cooling system to prevent overheating.
- Testing and Calibration: Thoroughly test your welding machine to ensure it operates as intended. Calibrate the control circuitry to achieve the desired welding parameters.
- Safety Testing: Ensure your machine complies with safety standards and regulations. Conduct safety tests to verify that it operates safely under various conditions.
- Documentation: Create comprehensive documentation, including user manuals and safety instructions.
- User Training: If you plan to use or distribute the machine, provide training to users on its safe operation.
Remember that building an arc welding machine is a complex task that requires expertise in electrical and mechanical engineering. It also involves safety risks, so safety should be a top priority throughout the design and construction process. If you do not have the necessary knowledge and experience, it is advisable to consult with experts or consider purchasing a commercially available welding machine. Additionally, always adhere to local safety regulations and standards when working with electrical equipment.