1. Welding Safety
What is the most important aspect of welding? The answer is simple: “ SAFETY”. What good does a beautiful weld and job well done do you if you’ve hurt yourself (or others) in the process?
Many dangerous elements make up any welding operation. You use massive amount of electricity to join metals (which are often sharp and heavy) through melting. You’re constantly at risk for electrical shock, serious eye injuries, and burns.
Welding safety is no accident! Be sure to take the precautions necessary to ensure your safety and the safety of those around you.
You also need to make sure anyone who comes near your welding projects is aware of proper welding safety practices so that they can help keep themselves safe as well. Here is some personal protection equipment:
- Gear up and protect yourself with recommended safety gear, including ample eye protection.
- Choosing the right welding shade for your weld process. “Auto Darkening or Passive lens” is recommended.
- Keeping the right fire extinguisher on hand
- Wearing protective clothing; Welding Jacket, Pants, Gloves, Safety boots, Hats/beanies, and Lather Jackets
- Using a respirator or fume extraction unit
- Keeping your workspace clean
- Getting the ventilation right
- Storing flammable liquids and gases
- Protecting yourself from electrical shock
- Maintaining your equipment and don’t hesitate to get professional repair help
- Ready your first-aid kit nearby
- Knowing how to handle injuries
2. Welding Workshop Set Up
If you want to succeed with any welding projects, you need to cover two bases: location and equipment. You can’t get very far with good welds without having the right kind of setup, from building itself to the tools and other gear you need to equip the space properly.
Some welders who are new to welding think they can simply clear out a space in the garages, buy a piece of welding equipment online and start making high-quality welds.
It’s not that simple, you need to think through all the requirements necessary for a welding space that allows you to do a good work and do it safely.
And when you’re talking about welding equipment and tools, you need to make sure you have all the basics (and maybe a few extras as well). Get the right teacher or training centre to provide you the basic knowledge before starting a welding project.
3. Tools Commonly Used for Welding
Here we will discuss about the tools and equipment you need to get your welding area set up right.
With this items, it will make welding easier, and in many cases, it will make the welding process – from start to clean-up – more enjoyable. You are going to be spending a lot of time with your tools if you really get into welding, so treat them well.
Be sure you buy tools that are the right size because tools that are too small or too large for you can be uncomfortable or dangerous.
- 4 inch grinder: Grinders are really dynamic tools and they are a cinch to use after you’ve had some practice. You rarely get all the way through a welding project without having to thoroughly clean or otherwise alter the surface of a metal, and a grinder is an excellent way to get that done in a fast, efficient way.
You may be amazed at how often you need to remove rust, grind and groove into something, or smooth down a rough surface. With a grinder, it has a variety of attachments you can use with it. You can use a flap disc to smooth something out.
Using a wire brush attachment, you will be able to clean up a piece of cast iron before welding. - Hacksaw: A hacksaw is a small versatile, handheld saw that allows you to use all kinds of different blades designed to cut various materials. It is relatively inexpensive and you’ll probably enjoy having it around.
- Air compressor: Many of the welding processes, particularly stick welding can create a mess and leave your projects covered with particles.
If you have a compressor with a blowgun attachment, you can use pressurized air to blow that stuff off on the floor so that you can easily broom it up later. That’s a lot quicker than having to wipe down or brush off all those surfaces. - 3/8 inch electric drill: This electric drill is one of the most common and most popular drills available and for good reason; you can use this kind of drill for all kinds of things in your home and shops. It’s great for drilling small holes in your welding jobs where necessary.
- Wrench set: When you are assembling or disassembling the parts of a welding project, a good wrench set can certainly come in handy. They are also great for adjusting you tools and other equipment. You can always just stick with an adjustable wrench, which is a versatile tool, but if you want a perfect fit.
- Cutoff saw: If you have not worked with a lot of metals in the past, you may not be familiar with cutoff saws, which are a little different from the saws you use to cut other materials such as wood.
Instead of using a blade, cutoff saws use an abrasive sheel to make cuts. The wheels are like grinding wheels but they’re quite thin. - Bench grinder: A bench grinder is a feat piece of equipment for general grinding tasks and for sharpening the tools in your shop. Bench grinders are usually about the size of a microwave, and you can attach them to the top of a workbench.
- Tools box: Toolboxes come in a variety of sizes, form the kind you can fit into the glove box of a car to the kind mounted on wheels that can hold a ton of tools. Because of the range in sizes, toolboxes can be quite expensive.
4. Commonly Welded Material
The top three material that is commonly picked will be steel, stainless steel and aluminium. Choosing the right material for your project is essential and it’s like a good chef knowing the right ingredient or a good carpenter who knows what wood to choose.
If you can familiarize yourself with those three metals and understand their characteristics then you’re well on your way to figuring out how to work with these three most common, versatile metals out there. Here are some basic properties of metals that you should know:
- Strength: How much external force the metal can take without breaking
- Ductility: The ability to change shape without breaking
- Magnetism: Some metals (like steel) are magnetic: others (like aluminium) aren’t
- Hardness: The resistance of metal to being damaged when another metal is applied to it
- Resistance to oxidization: When metals combine with oxygen, they become oxidized, and it causes them to rust.
- Electrical conductivity: Some metals conduct electricity much more efficiently than others.
- Melting point: Every metal had a melting point – the tempreture at which the metal turns from solid to liquid. This property is critical in welding because we are trying to melt the metal during welding.
5. Weld Preparation
All welding metals ferrous or non-ferrous have to be cleaned and prepare before you weld them. Quality welds aren’t going to happen if your material is covered with surface contaminants.
And some of those contaminants can be downright dangerous to your health if they’re heated up and converted to fumes while you’re welding.
Let us take the material carbon steel as an example: You especially need to do your best to remove rust from the surface of your stell. Rust is especially common on carbon steel and it can wreak havoc when you’re trying to produce a high-quality weld.
The most common defect you experience as a result of rust is porosity (the presence of lots of little holes) in your welds, and porosity can really ruin a good weld joint.
You can use one of two methods for cleaning your steel prior to welding; chemical, mechanical or laser. The method you choose depends on the metal type, the condition of the metal, the welding process you’re planning to use and the equipment available.
6. Choose the Right Welding Process
You can use heat to join metal in several different ways, but by far the most common welding methods used today are the arc welding (SMAW) methods.
Arc Welding is simple in theory: A large amount of electricity creates an arc between an electrode and base metal, and that arc generates enough heat to melt the materials in the weld area and join them together to make a weld.
In practical, arc welding includes three different welding processes (Stick, MIG and TIG) and has many different variables of other elements. For example, some kinds of arc welding use shielding gas, while others don’t.
The electrodes that you use in arc welding may be consumables, meaning they get melted and incorporated into the weld, or they may be non-consumable.
The electricity used in arc welding is the source of many other variables, including amperage (which varies) and current (either AC or DC current).
Here is a summary of the 3 most popular welding processes in the world.
- Stick Welding: It is also known as arc welding, Shielded Metal Arc Welding (SMAW), Manual Metal Arc Welding (MMA). This is the most common technique being used worldwide.
- MIG Welding: It is also known as Co2 welding, Gas Metal Arc Welding (GMAW) or Metal Inert Gas Welding (MIG). There is two types of shielding gases that can be used, and it depends on the type for material and filler wire use.
- TIG Welding: It is also known as Argon Welding, Gas Tungsten Arc Welding (GTAW), Tungsten Inert Gas Welding (TIG). This welding process is normally used in welding thin material. Material such as stainless steel and aluminium is very common in TIG welding.
7. Using the Right Accessories
Having the right accessories during welding may prevent accidents from happening. There is always some sort of danger in welding.
Tools are essential to welders to achieve a neat and robust weld, save time, and ensure optimal accuracy.
When choosing the right accessories for welding, never compromise on quality and over time it will provide you with the maximum cost and effectiveness as well.
Below is the list of welding accessories that is most important for you to begin your weld.
- Auto-darkening welding helmet: The first essential welding accessory you must have is a welding helmet.
The primary purpose of any welding helmet is to prevent sparks and flames from scarring your face while you work and prevent damage to the skin and eyes from the heat.
It filters away the unwanted UV and IR radiation and let only the visible light pass through and providing you with full protection to your eyes. An auto-darkening helmet will help in saving time and getting your weld started correctly. - Welding Magnets: These are the most versatile and useful tools that you will have in your kit. This allows you to mount pieces of metal and weld them together at an angle to one another.
They can also be used to hold pieces of metal in place without the use of clamps. They are inexpensive and readily available in a variety of sizes. - Work Holding Clamps: These help you to simplify your job setup tasks by providing quick clamping and secure holding without any distortion.
They also provide high clamping forces in a variety of space requirements thereby providing good accessibility to the workpiece. - Welding Jigs: These is not that necessary as compared to many of the other items listed above but it is still a nice piece of equipment to have.
- Welding Fume Extractor: This fume extraction unit can be used as a filtration system cleaning the air of harmful chemicals and particulates.
Welding processes create fumes including welding, grinding, sanding, spraying, powder filling and chemical application. - Weld Cleaning Machines: Cleaning after welding is very hectic but by using the TIG Brush, it can solve the problem associated with stainless steel cleaning solutions.
- Welding Machine: They offer a technological advantage in all welding procedures. It’s a matter of investing in the right product for a better solution. Selecting the ideal welding machines is of great priority.
8. Shielding Gas
For all welding processes to happen, the welder must be able to regulate the welding machine for the proper welding current and select the proper electrode size and type, as well as the right Shielding Gas.
These gasses are also known as inert or semi-inert gasses that are commonly used in welding processes, most notably GMAW and GTAW respectively. Their purpose is to protect the weld area from oxygen and water vapour.
Depending on the materials being welded, these atmospheric gases can reduce the quality of the weld or make the welding more difficult. Other arc welding processes use alternative methods of protecting the weld from the atmosphere as well.
For example, the SMAW process uses an electrode covered in flux that produces carbon dioxide when consumed.
Improper choice of welding gas can lead to a porous and weak weld, or the excessive spatter, while not affecting the weld itself, causes loss of productivity due to the labour needed to remove the scattered drops.
Below are the commonly mixes of shielding gas available in the market are argon, helium and carbon dioxide. In addition, a small amount of oxygen, nitrogen and hydrogen have proven beneficial for some applications.
Of these gases, only argon and helium are inert gases. Compensation for the oxidizing gases is made only for wire electrode formulations.
Argon, helium and carbon dioxide can be used alone, in combinations or mixed with others to provide defect-free welds in a variety of weld applications and weld processes.
9. Defect Analysis
The most common defect in welding is the “weld discontinuity” and “weld defect”. A discontinuity is some interruption of the weld’s typical structure, a location in the weld that is not like the usual parts of the weld.
It can be changed in mechanical, metallurgical, or physical characteristics of the weld and its immediately surrounding base metal. Every discontinuity causes a stress concentration within the weld.
Stress levels at concentration points may be many times the stress level of the surrounding material. While stress concentration may not cause immediate weldment failure, in time stress concentrations lead to cracks.
Cracks tend to grow larger with time and can ultimately lead to complete and catastrophic weld failure.
Dealing with defects in welding is normally done by a welding inspector and typically they will help in examining every aspect of the welding process to ensure the welds meet the welding specification procedure (WPS).
The type of inspections typically use are both destructive methods and non-destructive methods for testing the quality of the welds.
10. Type of Welder’s Qualification
Whether you are getting started in welding with intentions to become a full-time welder or are a hobbyist who’s thinking about taking your welding efforts to the next level, welding certifications is a great option.
They are a few national bodies that regulate and administers welding certifications in Malaysia. Namely CIDB Technologies, Proweld Training Centre, TWI, AWS, DV, and ISO.
Most welders will tell you the same thing about this certification: It’s an important step for a welder and one that is certainly recognized by the welding industry.
If you are young and willing to pursue a welding certification, most vocational schools and community colleges include some sort of welding program. In addition to welding certification, those locations often also offer welding courses that can help you with your welding knowledge and techniques.
For example, the courses from Proweld Training Centre are usually focused on a relatively narrow range of welding methods, so you can pick and choose the ones you want to get better at or just take them all and become a truly dynamic welder.
Most of the training centre facilities are fairly up to date. You may need to do some research before joining these kinds of classes and it all depends on your budget as well as the type of certification that you need.
For example, in Proweld Training Centre they use a welding simulator to provide their beginner student with familiarization with all welding processes. It’s like a pilot simulator before the actual aeroplane.
11. Maintenance, Repair, and Calibration of Welding Machines
Hundreds of companies can save thousands of dollars if proper maintenance, repair and calibration are done correctly. Taking care of the welding machine is a vital step that all welders must take, whether they’re doing it professionally or as a hobby.
As you can see the welding machines need to be maintained similarly like you maintain an auto vehicle as per se. A well maintains welding power source will provide you good returns in the years to come.
Proper upkeeping is something you shouldn’t take lightly as these machines contains many components that all require a special amount of care and protection to work properly. Here is some basic guideline for you to observe:
- Owner’s manual: You should always start by reading the welding machine manual. This manual will provide you with the technical specification and maintenance procedures for the welding machine. The most important key is to switch off the welding machine before beginning any maintenance tasks.
- Guns and torches: Welding guns and torches can become damaged or contaminated over time. This is why the welder must regularly inspect the particle build-up inside, as well as any connections that may be loose or otherwise damaged.
- Welding cables and earth leads: Frequently inspect all cables to ensure they aren’t loose, frayed, punctured, or compromised in any other way.
The cable can obtain damage by being regularly stepped on, improperly wrapped around an object or recklessly stored when not in use. If you see a damaged cable, immediately replace it as electric shocks are a common welding hazard. - Electrode holders: Like welding cables and earth leads, electrode holders can accrue damage over time. Regularly inspect electrode holders for cracks and wear and tear, replacing them when necessary.
- Wire feeders: Don’t forget to thoroughly inspect the wire feeder as well. If the feed rollers are dirty or damaged, you’ll need to act accordingly. The process is fairly easy for the maintenance of the feed roller.
If it’s dirty just clean it with a cleaning agent and if it’s broken or cracked just replace it. Don’t forget to inspect the inlet and outlet guides for damage either. Both the inlet and the outlet guide will need to be replaced if it is broken. - Hoses: To avoid producing a low-quality weld, you’ll also need to ensure the gas hoses are intact. To make sure the shielding gas is reaching its destination properly. Regularly inspect gas hoses for any cracks, punctures, wear and tear and other signs of leakage.
- Internal cleaning: Air blowing or vacuuming your welding machine is one of the most important tasks for ensuring the machine works properly. Over the course of multiple welds, dirt can work its way into the welding machine.
All welding machine has a built in fan for cooling, and normally the air are being sucked from the front panel of the welding machine. If the machine is laying on the ground then dust, and steel particles will be your number one issue.
These steel particles will create sparks within the machine, so simply use a vacuum or dry air to blow the dirt out of the welding machine, the frequency of which depends on how often you are well.
Monitor dirt accumulation in your welding machine and remove it when necessary, whether it’s weekly, monthly, or bi-monthly.
All welding calibrations such as inverter, rectifier, AC transformer, engine power welding machines should be calibrated and certified before use, and it should be done at least once a year.
This is to ensure the performance and consistent welding result of the welding equipment. In practice, calibration is the process of comparing indicated weld outputs (normally voltage and amperage) on the welding machine with a load bank.
The comparison is made to determine whether the equipment results are within the tolerance defined in the applicable standard.