STRUCTURAL STEEL SHAPES BASICS AND TUTORIALS

DIFFERENT STEEL SHAPES BASIC INFORMATION
What Are the Different Steel Structural Shapes?


Steel mills have a standard classification for the many products they make, one of which is structural shapes (heavy). By definition this classification takes in all shapes having at least one cross-sectional dimension of 3 in or more. Shapes of lesser size are classified as structural shapes (light) or, more specifically, bars.

Shapes are identified by their cross-sectional characteristics—angles, channels, beams, columns, tees, pipe, tubing, and piles. For convenience, structural shapes are simply identified by letter symbols as indicated in Table 7.3.

The industry recommended standard (adopted 1970) for indicating a specific size of beam or column-type shape on designs, purchase orders, shop drawings, etc., specifies listing of symbol, depth, and weight, in that order.

For example, W14 30 identifies a wide-flange shape with nominal depth of 14 in and weight of 30 lb / lin ft. The , read as ‘‘by,’’ is merely a separation.

Each shape has its particular functional use, but the workhorse of building construction is the wide-flange W section. For all practical purposes, W shapes have parallel flange surfaces.

The profile of a W shape of a given nominal depth and weight available from different producers is essentially the same, except for the size of fillets between web and flanges.

ARC WELDING TYPICAL PROCESSES BASICS AND TUTORIALS

TYPES OF ARC WELDING BASIC INFORMATION
What Are the Types of Arc Welding?


Shielded metal arc welding (SMAW): 
Shielded metal arc welding, which is also known as stick welding, is the most widely used process. The arc is struck between the metal to be welded and a flux coated consumable electrode.

The fluxes are mostly made from mineral components and cover the hot weld deposit and protect it from the environment. The solidified glassy product, slag should be removed by chipping or with a wire brush.

Gas metal arc welding (GMAW):
This process is also referred to as metal inert-gas (MIG) welding uses an uncoated continuous wire. The weld area is shielded from contamination by the gas that is fed through the welding torch.

The mode of metal transfer (spray, globular, short-circuiting, pulsed-arc) is varied by adjusting the amperage and the shielding gases used depending on the welding position and the type of joint.

Flux-cored arc welding (FCAW):
The shielding gases and slag are provided by the decomposing flux that is contained within the electrode. Auxiliary shielding is also used in certain instances where deeper penetration is needed.

Gas tungsten arc welding (GTAW): 
Also known as tungsten inert-gas (TIG), the process uses a non-consumable electrode. The shielding gas is again fed through the welding torch.

Welding may be accomplished without the addition of filler metal, which is advantageous especially for thin walled parts.