Welding Tutorial

SMAW

2006-12-29T21:23:00.000+08:00

Shielded Metal Arc Welding (SMAW) or Stick welding is a process which melts and joins metals by heating them with an arc between a coated metal electrode and the workpiece. The electrode outer coating, called flux, assists in creating the arc and provides the shielding gas and slag covering to protect the weld from contamination. The electrode core provides most of the weld filler metal.
When the electrode is moved along the workpiece at the correct speed the metal deposits in a uniform layer called a bead.
The Stick welding power source provides constant current (CC) and may be either alternating current (AC) or direct current (DC), depending on the electrode being used. The best welding characteristics are usually obtained using DC power sources.
The power in a welding circuit is measured in voltage and current. The voltage (Volts) is governed by the arc length between the electrode and the workpiece and is influenced by electrode diameter. Current is a more practical measure of the power in a weld circuit and is measured in amperes (Amps).
The amperage needed to weld depends on electrode diameter, the size and thickness of the pieces to be welded, and the position of the welding. Generally, a smaller electrode and lower amperage is needed to weld a small piece than a large piece of the same thickness. Thin metals require less current than thick metals, and a small electrode requires less amperage than a large one.
It is preferable to weld on work in the flat or horizontal position. However, when forced to weld in vertical or overhead positions it is helpful to reduce the amperage from that used when welding horizontally. Best welding results are achieved by maintaining a short arc, moving the electrode at a uniform speed, and feeding the electrode downward at a constant speed as it melts.

How Arc Welding works?

2006-12-24T21:29:00.000+08:00

Nice topic…really want to know. Let’s talk about it. In arc welding, the work to be welded becomes part of an electric circuit (hopefully you read last posting).

In a simple welding circuit, a power source (generator ) provides the current. From one pole on this source comes the electrode cables which carries the current. At the end of the cable is the electrode holder and the electrode itself. An electrode is a rod to melt down as filler metal. The current flows through the electrode cable into the electrode.

The electrode is held against the workpiece and then drawn back slightly causing a short. The electric current jumps the gap, creating a continuous spark which is called the arc. The workpiece is attached to ground cable which connects it to the opposite pole of the power source and completing the circuit.

welding current

2006-12-19T21:32:00.000+08:00

Okay…this week we will talk about …basic electric for welding. What??????? Why we should know about electrical. We are not electrician or wireman…just to weld the metal. That’s all.
I’m totally agree with you….. but the knowledge of basic electric will help you to improve the skill and how to operate welding machines. Anyway learn about electrical its not too difficult if we really understand how our water pipeline (hydraulic) at home. The principle quite and almost same.

Voltage is like a pressure in pipe
Amperage is flow of water in pipe
Transformer is used to step up or step down the current e.g from 11kv to 230v
Rectifier is used to change Alternate current AC to direct current DC.
Generator is used to produce electrical source for welding machine.

Personal Protection Equipment

2006-12-14T21:14:00.000+08:00

or PPE. What’s up man!!! .Its basic need for General work clothing is worn by each person in the shop. This stuff you can get from your near hardware shop or welding supplier.
Or you can buy via online : http://millerwelds.com/
Leather is often the best material to use, as it is lightweight, flexible, resist burning and is readily available.
The basic things you should wear it during welding (unless you’re really good and X-men).
1. Hand protection or leather gloves, gauntlet type.
2. Body protection; full leather jackets and capes will protect a welder’s shoulders, arm and chest.
3. Welding helmet to protect eyes and face from direct radiant energy and hot sparks.
4. Safety shoes. Safety boots with steel toes.

That’s only the basic personal protection wear during welding….. for home welding.

watch out !!!!

2006-12-08T07:34:00.000+08:00

Until now, you’re familiar with the word

s welding. But before we proceed with the basic principles of welding…..SAFETY FIRST (we should discuss it earlier).

Welding like other industrial jobs, has a number of potential safety hazards. Learning to work safely very important because these hazard can cause injury or fatal. Our safety is our responsibility, we must take that responsibility.

Examples:

Electric shock from welding electrode or wiring can kill.
Breathing welding fumes can be hazardous to your health.
Welding can cause fire or explosion
Arc rays can burn eyes and skin.

to be continue...

2006-12-03T21:10:00.001+08:00

WELD@home.com

Dear valued readers…..

I’m just starting my new project…. To setup a welding shop. So what?????
And what is welding ?. I’m wonder how its work and what it is. So, from today and onward we will talk all about this issues (but depends on your comments and feedback).

I’m asking you? What is welding ? Some of you will answer like this: “I think its has something to do with metal” or “It’s a way to join iron together”….and my grand father said..”when two metals fall in love and married”...ha-ha!!!!.

It is defined by American Welding Society as “A joining process that produces
coalescence of materials by heating them to welding temperature, with or without
the application of pressure or by the application of pressure alone and with or
without the use of filler metal.”

Its sound too technical language….Lets say that “A weld is made when the separate pieces (two or more) of metal to be combine and form one piece of metal.

Before we go more details and complicated on welding. Let’s look on the history of welding.

1. Egyptian used application of stone to create temples and pyramids that were fastened together with a gypsum mortar. more details click http://millerwelds.com/pdf/WorldofMetals.pdf

2. Workers in the Iron Ages began to solve the problems of forming and casting metals. Another method used was to place two pieces of metal close together and pour molten metal between them as figure show below;

Back to modern welding techniques are apply in the various industry such as building, bridge and even at our home products (looks at our gates, drain cover, grill and etc…I’ll tell how to make it soon in next posting).

To be continue…next posting about the basic welding equipment and how to setup @home.

Please give your comments…..TQ.