ARC 133 NVCC Metal

What can metal be classified as

Ferrous or Non-Ferrous

When two metals are combined what is it?

Alloy

How is something classified as ferrous?

The percentage of iron that’s in the metal

What are the three ferrous materials used in construction?

Cast Iron, Wrought Iron, and Steel

Whats the Carbon percentage of Cast Iron

2-4% carbon

Whats the weakness and strength of Cast Iron

High in compressive strength, low in tensile strength, can be molded into shapes

Whats cast iron used for

Waste pipes, fittings, bases of plumbing fixtures, and grill ornaments

What is Wrought Iron

A combo of pure iron and sla9 of iron silica

Whats the properties of wrought iron

Soft and easily shaped as rods, wires, handrails, etc.

What is Steel

An alloy of iron and up to 2% carbon

Whats the strengths of steel

Great strength in both tensile and compressive forces

What can steel contain besides iron and carbon

sulfur, phosphorus, silicon and manganese

Whats the classifications of steel

Low Carbon Steel: up to 0.25% Carbon

Medium Carbon Steel: with 0.25% up to 0.5%

High Carbon Steel: with 0.5% up to 2%

How is Steel produced

Produced in ingots ranging from 100lb to 25 tons usually in square or rectangular shapes

What is Blooming mill/ Cog mill/ Primary Mill

When ingots are heated to a desired temp and after passing through different types of rollers it finds its preliminary shape

Whats the products of blooming mill

A bloom, A billet, and a slab

Whats the dimensions of a bloom

ranges from 6×6 to 12×12

Whats the dimensions of a billet

2×2 to 5×5

Whats the dimensions of a slab

2” to 6” and over 24” wide

What does W10×122 mean

“W” means Wide Flange beam, 10 means the depth of the the beam, 122 is the pounds

Wide Flange Beam aka H beam, symbol is “W”

American standard beam aka I beam, symbol is “S”

American Standard Channel, symbol is “C”

Steel Angles, symbol is “L”, wrote as 4(first leg)x4(second leg) x ¼ (thickness)

Steel structural Tee shape, symbol is “WT”

steel plates are available at what thickness

1/8 to 3”

What is the 4 ways steel is classified

methods of manufacture, heat treatment, chemical composition, reference to recognized standard

Whats the four different types of steel

1. Carbon steel, 2. Alloy steel, 3. High strength low alloy steel, 4. Stainless steel

What's the composition of carbon steel

over 95% iron, not over 2% carbon, .6% copper, 1.65% manganese, .6% silicon

Whats alloy steel

Alloy elements added to carbon steel, gives different characteristics, ex. copper alloy steel is resistant to moisture

What is High strength, Low alloy steel

called weathering steel, 40% more strength than carbon steel, resists corrosion

What is stainless steel

Corrosion resistant from chromium added

what’s the percentage of chromium in stainless steel

11.5% chromium

Whats the 3 functions of steel in a construction site

1. Structural steel

2. Miscellaneous steel

3. Carpenters Steel

Whats structural steel

Consists of structural shapes, plates not less than 1/8” thickness, fasteners like bolts and anchors

Whats miscellaneous steel

All other steel members that aren’t apart of the structure

whats Carpenters Iron

Consists of all steel fasteners like nails and bolts for wood construction

Whats the most common structural steel in ASTM terms

ASTM A36, yield point of 36,000

Whats the 3 basic types of steel construction

1. Wall bearing

2. skeleton framing

3. Long span steel construction

Whats wall bearing steel

Structure loads from steel beams will be transferring to load bearing concrete or masonry walls

Whats skeleton framing

building with steel framing

Whats long span steel construction

in buildings like aircraft hangers, they require great distance between columns

Whats the 5 methods of long span steel construction

1. built-up girders

2. trusses

3. arches

4. rigid frame

5. cable hang

Whats built up girders

the top and bottom flanges resist the bending movements and the web acts as a spacer to keep flanges apart

built-up girder

box girder

howe truss, goes with the beginning diagonal

pratt truss, goes against the beginning diagonal

warren truss

bowspring truss

king post truss

Fink truss

scissors truss

Whats a benefit of arches

they support the walls and the roof aswell

two hinge arch, commonly used

three hinge arch, used commonly

What do hinges absorb

horizontal forces

whats an arch with no hinges

fixed arch, used on rocky surfaces

Whats rigid frame bents

A beam and two posts connected to each other with calculated details of connections 20’ to 24’, beams called purlins run perpendicular to these bents, 4’ to 5’ apart

How does fire proofing work for structural steel

Exposed structural steel must be covered with insulation to prevent the steel temp from going over 1000 F during a fire

What are the four ways to connect steel

1. rivets

2. unfinished bolts

3. highstrength bolts

4. weld

rivets, heated red hot then placed in holes 1/16” larger than the shank diameter

What are unfinished bolts

bolts used to temporarily hold steel members until a high strength bolt can be placed

High strength Bolts

same strength as rivets, more resistant to vibrations, bolts are tightened with pneumatic impact wrench

welding

electrode makes a continuous electric arc that generates heat enough to melt the localized area

fillet weld

lap weld

groove weld doesn’t go all the way through

butt weld

What is the selection of steel roof and floor based on

1. span

2. load to be applied

3. depth weight

4. fire resistance

5. cost

what is the lightest roof and floor systems

Open web steel joint

How is the open web steel joint produced

produced to up to 144’ span with a depth of 72” but standard sizes are 8” to 24”

If open web steel joints are used for roof what can it be

double pitched or single pitched top chord

whats the top chords slope

1/8” per foot slope

Steel deck can either be what

Light gauge galvanized or painted steel

corrugated single steel sheet for steel deck

Built up cellular unit, creates open area for electrical and mechanical lines

What is steel deck used for

As a base to pour lightweight concrete

whats the standard depth of decking

ranges from 1 ½ to 2 ½

What is done after welding the steel deck to the structural steel frame

reinforcements and shear studs are welded to the main beam every few inches then concrete is poured

Whats the standard web sizes for Light gauge steel members

web sizes are 2 ½ inches to 14 inches

Whats the standard flange sizes for Light gauge steel members

1 3/8 in, 1 5/8 in, 2 in, 2 ½ in, 3 inches

Whats the standard thickness sizes for Light gauge steel members

20 gauge to 12 gauge

Aluminum

non ferrous, highly resistant to weather, corrosive industrial and seacoast atmosphere

Why isn’t pure aluminum used

its very corrosion resistant but is extremely weak

how many standard aluminum alloys are there

50

Whats the PSI of aluminum alloys

20k to 68k psi

Mechanical and chemical finish

gives surface texture to aluminum

porcelain enamels finish

gives colorful, hard, heat resistant surface by fusing glass and finely ground pigments to the surface at high temp

Anodizing finish

aluminum place in electrolytic bath of sulfuric acid giving it a hard thin layer of aluminum oxide

Whats the difference between anodizing dyes and hard coating aluminum

dyes are added into the oxides coating and the hard coating is a coloring that happens to different aluminum alloying while anodizing

Whats cladding

when aluminum sheets cover external structures like beams, columns, windows, braces

Whats lead used for

nonferrous, waterproofing, sound/vibration insulation, corrosion resistant, heavy

How is thickness measured for lead

Pounds per sq ft, EX. 1/64” thick lead sheet weighs 1 pound so 1lb/sq ft

What is lead coated steel called

terneplate, used for roofing, cutters, flashing and metal doors

What is zinc

nonferrous, bluish white, resists corrosion by water, zinc coated steel is called galvanized steel

Copper is used for what

its resistance to corrosion, tensile strength, workability, and conductivity

24” wide or less copper is called what

strip copper

24” wide or more is called what

sheet copper

Brass is an allow of what

copper and zinc