Metals

Traditionally there are six different kinds of metals, namely gold, silver, copper, iron, tin and lead. 

Light weight metals include: aluminum, magnesium, titanium, and beryllium alloys. Aluminum and aluminum alloys are lightweight, non-ferrous metals with good corrosion resistance, ductility, and strength. Aluminum is relatively easy to fabricate by forming, machining, or welding.

Ferrous Metals Non-Ferrous Metals
Alloy Steel Aluminum
Carbon Steel Beryllium
HSLA Steel Copper
Iron-based superalloys Magnesium
Ferrous metals include: mild steel, carbon steel, stainless steel, cast iron, and wrought iron. These metals are primarily used for their tensile strength and durability, especially mild steel which helps hold up the tallest skyscrapers and the longest bridges in the world.
Screenshot (672)
Non-Ferrous Metals: do not contain Iron, are not magnetic and are usually more resistant to corrosion than ferrous metals. Some examples of Non-Ferrous Metals we deal with are: Aluminium & Aluminium Alloys. Copper.
Screenshot (671)
According to the American Iron and Steel Institute (AISI), steel can be broadly categorized into four groups based on their chemical compositions:
  • Carbon Steels.
  • Alloy Steels.
  • Stainless Steels.
  • Tool Steels.
Five common metal finishes that can influence the way metals look:
  • Aluminum. Similar in appearance to stainless steel, aluminum is lighter and less strong than steel. …
  • Brass. …
  • Copper. …
  • Stainless Steel. …
  • Wrought Iron. …
  • 5 Common Metal Finishes.
An alloy: is a mixture of metals or a mixture of a metal and another element. Alloys are defined by a metallic bonding character. An alloy may be a solid solution of metal elements (a single phase) or a mixture of metallic phases (two or more solutions).

Ingredients of Steel

  • Carbon – This ingredient is essential to steel’s creation; all steel will have some amount of carbon. It is the most important hardening element, but as it is added it can reduce the toughness of the material.
  • Chromium – Combats corrosion. Chromium will also increase the strength of the material, but adding chromium in large amounts decreases toughness.
  • Cobalt – Strengthens the the material
  • Copper – Combats corrosion.
  • Manganese – Hardens the material. If added in high quantities it can increase brittleness.
  • Molybdenum – Maintains the steel’s strength at high temperatures.
  • Nickel – Adds toughness.
  • Nitrogen – This element is sometimes used as a replacement for carbon in steel.
  • Phosphorus – Improves strength.
  • Silicon – Increases strength. Also, removes oxygen from the metal while it is being formed.
  • Sulfur – Increases machinability but decreases toughness.
  • Tungsten – Increases wear resistance.
  • Vanadium – Increases wear resistance and makes the material harder.

Types of Steel

There are literally thousands of types of steel. Among them, the most common are carbon steels, alloy steels, tool steels, and stainless steels. Each of these types of steel has a designation system that gives them a specific number.

Plain carbon steels are steels that contain iron, carbon, and a small amount of manganese. In contrast, alloy steels have a specified composition and contain certain percentages of vanadium or molybdenum, and they also typically have a larger amount of manganese. Tool steel contains tungsten, molybdenum, and other alloying elements.

The National Institute of Standards and Technology notes that “steel has become one of the most reliable, most used and most important materials of the age.” As an advanced engineered material, steel is the material of choice by engineers and architects because of its strong performance characteristics, reliability, versatility in design, consistency as a product and “green” profile.

The American Iron and Steel Institute’s mission is to influence public policy, educate and shape public opinion in support of a strong, sustainable U.S. and North American steel industry committed to manufacturing products that meet society’s needs.

Steel continues to provide a proven environmentally responsible solution for meeting green building requirements in sustainability standards.

  • Steel is the most recycled material in the world, more than aluminum, copper, paper, glass and plastic combined. In North America alone, more than 60 million tons of steel are recycled or exported for recycling each year.
  • Today, 97 percent of steel by-products can be re-used and the recycling rate for steel itself is 86 percent.
  • Through recycling, the steel industry saves the energy needed to power 20 million homes for one year.
  • Advanced high-strength steel is the only material that reduces greenhouse gas emissions in all phases of an automobile’s life: manufacturing, driving and end-of-life.
  • Since 1990, the industry has reduced energy intensity by 31 percent and CO2 emissions by 36 percent per ton of steel shipped.
  • The North American steel industry is committed to the highest safety and health standards. Since 2005, U.S. steel producers have achieved a reduction of 70 percent in both the total OSHA recorded injury and illness and lost workday case rates.

 

 

 

 

 

 

 

source:steelwrksAISI

 

Connections

 

Steel Connections | Overview

  • ƒ Connections are the glue that holds a steel structure together.
  • ƒ Historically, most major structural failures have been due to some form of connection failure.
  • ƒ Steel connections have a direct influence on the cost of the framing system.
  • ƒ While a connection may be efficient in the use of material, it may still be very expensive to erect.
  • ƒ Repetitive connection design may save costs
  • ƒ Most connections have the connecting material (plates,angles, …) attached to one member in the fabrication shop and to the other members in the field.
  • ƒ It is a common practice to weld shop attachments and to bolt field attachments.
  • ƒ If the supporting girder and a supported beam have the same depth, the supported beam must be double coped.
  • ƒ End-plate connections are always shop welded.

Steel Connections | Bolted Connections

  • ƒ Bolting is the preferred method of connecting members on the site. Staggered bolt layout allows easier access for tightening with a pneumatic wrench when a connection is all bolted .
  • ƒ High strength bolts may be snug-tightened or slip-critical.
  • ƒ Snug-tightened connections are referred to as bearing connections
  • ƒ Bolts in a slip-critical connection act like clamps holding the plies of the material together.
  • ƒ Bearing type connections may have threads included ( TypeN ) or excluded (TypeX ) from the shear plane(s).
  • ƒ Including the threads in the shear plan reduces the strength of the connection by approximately 25%.
  • ƒ Loading along the length of the bolt puts the bolt in axial tension.
  • ƒ If tension failure occurs, it usually takes place at the threaded section.
  • ƒ Three types of high strength bolts: A325, A490 (Hexagonal Head Bolts), and F1852 (Button Head Bolt)
  • ƒ A325 may be galvanized A490 bolts must not be galvanized F1852 bolts are mechanically galvanized
  • ƒ High strength bolts are most commonly available in 5/8” – 1 ½” diameters
  • ƒ Bolting requires punching or drilling of holes
  • ƒ Holes may be standard size holes, oversize holes, short slotted holes, long slotted holes.

Steel Connections | Welded Connections

  • ƒ Due to high costs of labor, extensive field -welding is the most expensive component in a steel frame.
  • ƒ Welding should be performed on bare metal.
  • ƒ Shop welding is preferred over field welding.
  • ƒ The weld material should have a higher strength than the pieces being connected.
  •  ƒ Single-pass welds are more economical than multi-pass welds.
  • ƒ The most economical size weld that may be horizontally deposited in one pass has 5/16”.
  • ƒ Fillet welds and groove welds make up the majority of all structural welds.
  • ƒ The strength of a fillet weld is directly proportional to the weld’s throat dimension.
  • ƒ The capacity of a weld depends on the weld’s throat dimension and its length.

Steel Connections | Shear Connections

  • ƒ Shear connections are the most prevalent type of connections in a steel frame building.
  • ƒ Shear connections are called simple connections since they are assumed not to transfer bending moment, thus allowing end rotation of the member.
  • ƒ Shear connections may be made to the web of the supported member while the flanges remain unconnected.
  • ƒ Seat or hanger connections are the only type of shear connections that connect to the flange of the supported beam.
  • ƒ Angles for shear connections may be attached to supporting members by bolting or welding.
  • ƒ Although single plate connections, are the most economical, they must sometimes be evaluated for eccentricity.
  • ƒ Single angle connections allow end-rotation for flexible connections.
  • ƒ Single angle connections tend to have lower load capacities than double-angle connections.
  • ƒ Moment connections are also called rigid connections.
  • ƒ Moment connections carry a portion or the full moment capacity of the supported member thus preventing any end-rotation of the member.
  • ƒ Moment connections are typically designed to also carry the shear component of the load.
  • ƒ Moment connections provide continuity between the supported and supporting members.
  • ƒ Relative rotation between the supporting and supported members is negligible.
  • ƒ The flanges of the supported member are attached to either a connection element or directly to the supporting member.

Screenshot (453) Screenshot (468).png

Shop-Bolted Double Angle | Field-Bolted Beam to Girder or Column

  • ƒ Double angles are shop-bolted to the web of the beam.
  • ƒ If the beam and girder have the same depth, then both flanges of the beam are coped to meet flush with the top flange of the girder.
  • ƒ The double angles are then field-bolted to the web of the girder.
  • ƒ The holes on the beam and the girder may be offset with respect to each other for ease of fastening.
  • ƒ Some rotation is possible in the gap between the beam flanges and the column web. This happens by the yielding of the connection material (the outstanding angle leg)
  • ƒ This is a shear connection since the double angles are fastened to the web, and transfer the load in shear.
  • ƒ The bolts on the beam web are in double shear. Those on the girder web are in single shear.
  • ƒ Double angles are shop-welded to the web of the beam.
  • ƒ If the beam and girder have different depth, the top flange of the beam is coped to meet flush with the top flange of the girder.
  • ƒ The double angles are then field-bolted to the web of the girder.
  • ƒ Some rotation is possible in the gap between the beam flanges and the column web. This happens by the yielding of the connection material (the outstanding angle leg).
  • ƒ This is a shear connection since the double angles are fastened to the web, and transfer the load in shear.
  • ƒ The bolts on the girder web are in single shear.
  • ƒ Double angles are shop-welded to the web of the beam.
  • ƒ If the beam flanges are too wide to fit in between the column flanges, the beam flanges will be coped.
  • ƒ Some rotation is possible in the gap between the beam flanges and the column web. This happens by the yielding of the connection material (the outstanding angle leg)
  • ƒ This is a shear connection since the double angles are fastened to the webs of the beam and column.
  • ƒ The vertical segment of the weld transfers the load from the beam web to the column web.
  • ƒ Welding all around the outstanding leg will inhibit the flexibility of the connection.
  • ƒ The weld at the top is limited to a weld-return.
  • ƒ The weld at the bottom is optional.

Shop-Welded Double Angle | Field-Welded Beam to Column Web

  • ƒ End plate is shop-welded to the web of the beam.
  • ƒ Holes in the end plate are punched in the shop.
  • ƒ Some rotation is possible in the gap between the beam flanges and the column web. This happens by the yielding of the connection material (the outstanding angle leg) The end plate is then field-bolted to the web of the girder.
  • ƒ This is a shear connection as the end plate is fastened to the web of the girder (beam flanges are not secured against rotation)
  • ƒ The bolts attaching the end plate to the girder web are in single shear

Unstiffened Seat | Shop-Welded and Field-Bolted

  • ƒ The angles are pre-drilled or punched in the shop before they are welded to the girder or column.
  • ƒ The bottom angle is called the seat.
  • ƒ The seat is where the girder transfers its load to the column in bearing.
  • ƒ The top angle provides stability to the girder.
  • ƒ The seat angle is larger and thicker since it transfers the load from the girder to the column.
  • ƒ Unlike others, this shear connection is not made to the web.

Shop-Welded Single Plate | Field-Bolted Plate to Beam or Column

  • ƒ The single plate is pre-drilled or punched and then shop-welded to the supporting column or girder web.
  • ƒ The beam may be swung into place instead of lowered into place.
  • ƒ The top flange of the beam is coped to match the girder elevation.
  • ƒ This is a shear connection since the single plate is fastened to the web of the beam.
  • ƒ The bolts shown are in single shear.
  • ƒ This connection can transfer a small amount of moment to the supporting member

Shop-Welded Flange Plates | Field-Bolted Girder to Column

  • ƒ The top and bottom flange plates are pre- drilled and then shop-welded to the column.
  • ƒ The top and bottom flange plates are field-bolted to the girder flanges.
  • ƒ The flange plates are cut to fill the space between the column flanges.
  • ƒ The single plate on the girder web transfers shear to the column.
  • ƒ The flange plates prevent rotation and thus the transfer of moment forces to the column
  • ƒ Allowance for shims must be made. Mill tolerance on beam depth needs to be accommodated.

Shop-Welded Flange Plates | Field-Bolted Girder to Column

  • ƒ The top and bottom flanges are pre-drilled and then shop-welded to the column.
  • ƒ The single plate is shop-bolted to the web of the girder.

Shop-Welded Flange Plates | Field-Bolted Girder to Column

  • ƒ The top and bottom flange plates are field-welded to the girder flanges.
  • ƒ The single plate is field-welded to the column web.
  • ƒ The flange plates are cut to fill the space between the column flanges.
  • 4.ƒ The corners of the flange plates are clipped to eliminate the development of stress concentrations at the re-entrant (back) corners.
  • ƒ These corners are left open and are not welded.
  • ƒ The single plate on the girder web transfers shear to the column
  • ƒ The flange plates prevent rotation and thus the transfer of moment
  • forces to the column, which makes this a moment connection
  • ƒ Allowance for shims must be made. Mill tolerance on beam depth needs to be accommodated.

Shop-Welded End Plate | Field-Bolted Girder to Column

  • ƒ The end plate is pre-drilled and shop-welded to the end of the girder.
  • ƒ The corresponding holes in the column flange are pre-drilled.
  • ƒ The two transverse stiffener plates are shop welded to secure the column flanges against the load transferred from the girder flanges.
  • ƒ Extended end-plate connections require tight fabrication and erection tolerances.
  • ƒ Extended end plate prevents rotation and thus transfers moment forces to the column which makes this a moment connection.

Field-Bolted Moment Splice | Girder to Girder or Column Connection

  • ƒ All holes in this connection are pre-drilled in the shop.
  • ƒ The web and flanges of each girder are pre-drilled.
  • ƒ (2) Shear plates are field-bolted in each side of the webs.
  • ƒ The plates that attach the (2) webs to each other are responsible for transferring shear.
  • ƒ Pre-drilled flange plates are field-bolted to the top and bottom flanges.
  • ƒ The flange plates are responsible for transferring bending moments across the connection.
  • ƒ The bolts fastening the web plates are in double shear.
  • ƒ The flange plates prohibit any rotation and so this is a moment connection.

Shop-Welded or Shop Bolted Splice | Connecting Two Different Columns

  • ƒ The plates are pre-punched and then shop-welded to the lower (larger) column.
  • ƒ The flange splice plates are field-bolted together.
  • ƒ If the two columns have the same depth, but different flange thickness, then a filler plate or shim is used to make up the difference in thickness.

Field – Welded Column Splice

  • ƒ A temporary plate or erection aid is either welded or bolted to the web and / or flange of the lower (larger) column in the shop.
  • ƒ Flange plates may also be required for stability of the column during erection.
  • ƒ This plate helps align the upper and lower columns.
  • ƒ The upper and lower columns may be of different sizes.
  • ƒ The flanges and webs of the two columns are field- welded to each other.
  • ƒ This type of weld is called a groove weld.

Example of 3D frame model cropped - Graitec UK Ltd.PNG

Steel Connections | Bolted Connections

Shop-Welded Flange Plates | Field-Bolted Girder to Column

Connections are structural elements used for joining different members of a structural steel frame work.  Steel Structure is an assemblage of different member such as “BEAMS,COLUMNS” which are connected to one other, usually at member ends fasteners, so that it shows a single composite unit.

The following parameters define subsequent connection types:

  • frame knee, beam-beam, column-beam connection
    • bar section parameters
    • base parameters
    • stiffener parameters
    • anchorage parameters
    • concrete, weld and wedge parameters
  • column-base connection
    • bar section parameters
    • reinforcement parameters
    • screw parameters
    • stiffener and plate parameters
    • depth of concrete base
  • angle connection
    • bar section parameters
    • angle parameters
    • bolt parameters
    • cut dimensions, distances, etc.
  • pipe connection
    • connection type (unilateral, bilateral)
    • parameters of adjoining bars (crosses)
    • bracket parameters
    • weld parameters
  •  gusset connection
    • connection type (welded, bolted) and its parameters
    • bar parameters etc.

Structural Connection

prefabricated, reinforced  concrete construction, the two types of connections used for joining beams, columns, slabs, and panels are the reinforced-concrete type and the metal type. In the reinforced-concrete type, provision is made for the transfer of forces by welding or by an overlap of the reinforcing rods with subsequent sealing of the joint with concrete. In the metallic type of connection, the forces are transferred by welding together steel insertion elements anchored inside the units being joined.

metal construction welded connections, which are the most common, riveted connections, and bolted connections are the principal types. The use of welded connections in structures subject to alternating or dynamic loads, for example, bridge sand the booms of heavy-duty cranes, is limited in view of the adverse effect of such loads on the durability of welded joints. In riveted connections, forces are transferred either directly through the members being joined, as in a lap joint, or by means of additional plates, as in a butt joint. Bolted connections are used mainly in assembly; their design and functioning is similar to that of riveted connections. Bolted connections using high-strength bolts made from heat-treated steel are very effective.

beam to column rigid joints

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source:engnr/CISCdesign/AISC

 

 

 

 

20-Foot-Tall Steelworkers of Iron

Titled “The Workers,” the giant angular metal men are meant to forge a connection between Pittsburgh’s old labor force and its new artistic denizens.

The Workers, a sculpture of two 20-foot-tall metal men and a big steel mill ladle. The sculptures were set into place on Labor Day weekend 2012.

The materials were free, moving them was costly. Each of the workers weighs 10,000 pounds and the ladle weighs 20 tons.

The worker on the right is the Pourer. The worker on the left is the Puddler.  (The slag congealed on the lip of the ladle is real.) 

Image result for metal statues in pittsburgh 

Artist: Tim Kaulen: is a co-founder of the Industrial Arts Co-Op, a seminal local group that in the mid-1990s began creating large experimental sculptures in Pittsburgh’s abandoned mills, factories and warehouses. Mostly using materials found on site, the group has built a reputation around several high-profile efforts.

Two metal steelworkers each stand 20 feet tall and are made from four tons apiece of scrap metal, mostly steel and iron girders from a nearby bridge. The sculpture also includes an authentic tool used in the manufacturing of steel. They stand as if pouring molten steel from a 15-ton hot metal ladle, salvaged from a local steel mill, which now tips into a bed of flowers.

The statues, which look like beta test version Decepticons, took 15 years to complete, mostly because their costs ballooned from $25k to $200k.

The Workers were constructed with symbolic meaning. The metal used to build the giants was recycled from Pittsburgh’s steel infrastructure. The spot where the sculpture stands is a park that used to be a rail yard that serviced the Pittsburgh mills. The Workers had to be huge so that they would dwarf the ladle (reversing the usual size relationship) to show humankind’s ascendancy over industry.

The artist, Tim Kaulen generously stresses to emphasize that the project was a group effort. This project is the result of a community wide collaboration, with tremendous support from the artist, Industrial Arts Coop members, the City of Pittsburgh, Office of Public Art, Greater Pittsburgh Arts Council, Volunteer Lawyers for the Arts, PJ Dick Construction, and many, many public and private funders.

Twenty-four different artists, part of a regional arts collective named the Industrial Arts Co-op, lent their hands to design, assemble, cut, weld, adjust, bolt, grind, and sandblast the sculpture.

 

Intended to commemorate the region’s steel heritage, this 15-year project shouldn’t be seen as a memorial to Big Steel, but rather a link between Pittsburgh’s industrial past and its artistic present. Regardless of the clothes worn in our jobs, we still follow the same work ethic.the sculpture consists of two 18’x 6’ steel figures fashioned from iron reclaimed from the local industrial landscape and the renovated Hot Metal Street Bridge. The sculpture has been installed on the site of a former steel mill site as a tribute to Pittsburgh’s labor and industry heritage.

The Southside Works Sculpture Project commemorates the rich industrial steel heritage of the Pittsburgh region and honors the individuals who contributed to it, while at the same time, celebrates the present-day transformation of one of this country’s most important cities into a contemporary, stimulating place for people to live, work, and perhaps most importantly, contribute. The project uniquely captures the essence of Pittsburgh’s glorious steel heritage and creates a welcome addition of Pittsburgh-based public art.

Address: Three Rivers Heritage Trail, Pittsburgh, PA
Directions: On the south side of the Monongahela River in Southside Riverfront Park. From Hwy 837/E. Carson St. turn north onto S. 18th St. Drive six blocks, then cross the train tracks and enter the park. Follow the road as it turns sharply right. Drive a quarter-mile to the parking area, where the statues stand.
Admission: Free

 

 

source:PghCityPaper

 

 

Structural Steel Checker

Why is checking steel shop drawings important?

Steel shop drawings cannot be interpreted the way detailed drawings are able to be understood by the fabrication shop. They are specialized, precise, instructions to the fabricator. Checking is therefore very important, as the entire geometry of the building is generally in the control the steel detailer. The checker reduces the chance of individual errors.

Qualifications required for a checker:

1. Experience in steel fabrication procedures

2. Strong geometry skills

3. Attention to detail

Screenshot (383)

Areas to focus on:

1. Design compliance

2. Geometric accuracy

3. Buildabilitiy

Recommended checking procedures:

Check primary building datums first, (an engineering and drafting datum is, a reference point, surface, or axis on an object against which measurements are made.)

This often requires the checker to create his own layout:

1.Bay spacing

1.Span

1.Roof pitch

The following items fit in around a datum: (If the primary datum is correct, there is little chance of the detailer making a major mistake.)

2. Check secondary building datum

3. Column, rafter, bracing member sizes

4. Bracing set-out

5. Purlin member sizes and spacing: (longitudinal, horizontal, structural member in a roof, except a type of framing with what is called a crown plate).

6. Bolt size

7. Plate size

Every number must be checked. Therefore it is advantageous to have a thorough method of communication from the checker back to the detailer.

Screenshot (388)

Drawing markup method:

A well marked up drawing is an excellent way of communication from the checker:

1. If a checker agrees with a number, the number is highlighted in blue pencil.

2. If a checker disagrees with a number or line-work, it is marked up in red pen.

3. If the checker has a comment to make, it is written in normal pencil.

Screenshot (384)

The color-system checking process:

Ultimately the detailer is responsible for the integrity of the drawing, which could result in one person having too much geometric responsibility.

The following is a process that has been proven, to be a way of reducing errors to an acceptable level:

1. The checker marks up the drawings, as described above:

2. If the detailer agrees with the checkers red markups the area is then marked with yellow highlighter. 

3. Red markups the detailer disagrees with, are marked with orange highlighter.

4. The completed drawing and the markups are returned to the Checker.

5. Orange markups are discussed with the detailer until there is a resolution. upon completion, the checker signs the final drawing.

Screenshot (385)

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Typical parts of a shop drawing set:

The following drawing sections need to be checked:

1. Assembly drawings

2. Single parts

3. Purlin orders

4. Holding down bolt plan

5. General arrangement plan

6. End wall-building elevations

7. Field bolt list

8. Drawing index

Checking of steel structural drawings for industrial, residential and

commercial complexes structures like column, beam, bracing, trusses,

miscellaneous, etc., using Tekla Structures with complete deliverable

documents as per client requirements.

  •  Fabrication drawing delivery in charge.
  • Preparation of RFI & queries related to the project including: missing dimensions, member placements and connections.
  • Monitoring the progress of the project at various stages of work in modeling, editing, checking & delivering the drawings.
  • Preparation & checking of erection drawing.
  • Preparation of material take off.

 

 

source:TechnicalDrawing/resource

𝐓𝐡𝐞 𝐁𝐫𝐢𝐝𝐠𝐞𝐬 𝐨𝐟 𝐏𝐢𝐭𝐭𝐬𝐛𝐮𝐫𝐠𝐡

The Bridges of Pittsburgh play an important role in the city’s transportation system, without bridges, the Pittsburgh region would be a series of fragmented valleys, hillsides, river plains, and isolated communities.

𝐏𝐢𝐭𝐭𝐬𝐛𝐮𝐫𝐠𝐡 𝐢𝐬 𝐤𝐧𝐨𝐰𝐧 𝐚𝐬: “𝐓𝐡𝐞 𝐂𝐢𝐭𝐲 𝐨𝐟 𝐁𝐫𝐢𝐝𝐠𝐞𝐬”
A 2006 study determined that Pittsburgh has 446 bridges, and with its proximity to three major rivers and countless hills and ravines, The Smithfield Street Bridge, which spans the Monongahela River, connecting downtown Pittsburgh to Station Square, is the oldest steel bridge in the United States. It was designed by Lindenthal and completed in 1883.

A list of some of the bridges in Pittsburgh

  1. The David McCullough Bridge, commonly and historically known as the 16th Street Bridge, is a through arch bridge that spans the Allegheny River in Pittsburgh, Pennsylvania.
  2. The Liberty Bridge, completed in 1928, connects downtown Pittsburgh, Pennsylvania, to the Liberty Tunnels and the South Hills neighborhoods beyond. It crosses the Monongahela River and intersects Interstate 579 (the Crosstown Boulevard).
  3. The Fort Duquesne Bridge, is a steel tied arch bridge that spans the Allegheny River in Pittsburgh, Pennsylvania. It was colloquially referred to as “The Bridge to Nowhere”.
  4. The Hot Metal Bridge, is a truss bridge in Pittsburgh, Pennsylvania, that crosses the Monongahela River.
  5. The Andy Warhol Bridge, also known as the Seventh Street Bridge, spans the Allegheny River in Downtown Pittsburgh, Pennsylvania and is the only bridge in the United States named for a visual artist.
  6. The Smithfield Street Bridge, is a lenticular truss bridge crossing the Monongahela River in Pittsburgh, Pennsylvania, USA. The bridge was designed by Gustav Lindenthal, the engineer who later designed the Hell Gate Bridge in New York City.
  7. The Rachel Carson Bridge, also known as the Ninth Street Bridge, spans the Allegheny River in Downtown Pittsburgh, Pennsylvania in the United States.
  8. The McKees Rocks Bridge, is a steel trussed through arch bridge which carries the Blue Belt across the Ohio River at Brighton Heights and McKees Rocks, Pennsylvania, west of Pittsburgh.
  9. The Roberto Clemente Bridge, also known as the Sixth Street Bridge, spans the Allegheny River in downtown Pittsburgh, Pennsylvania, United States.
  10. The Birmingham Bridge, is a tied arch bridge in Pittsburgh, Pennsylvania, which crosses over the Monongahela River.
  11. The South Tenth Street Bridge, most often called the Tenth Street Bridge, but officially dubbed the Philip Murray Bridge, is a suspension bridge spanning the Monongahela River in Downtown Pittsburgh, Pennsylvania.
  12. The Fort Pitt Bridge, is a steel double decker bowstring arch bridge that spans the Monongahela River near its confluence with the Allegheny River in Pittsburgh, Pennsylvania.
  13. The West End Bridge, is a steel bowstring arch bridge over the Ohio River in Pittsburgh, Pennsylvania, approximately one mile below the confluence of the Allegheny and Monongahela Rivers.
  14. The Homestead Grays Bridge, also known as the High Level Bridge, was built in 1936 and spans the Monongahela River between Homestead Borough and the southernmost tip of Pittsburgh’s Squirrel Hill neighborhood.
  15. The George Rankin Jr. Memorial Bridge, is a cantilever bridge that carries the Green Belt across the Monongahela River between Whitaker and Rankin in Pennsylvania in the USA.
  16. The Fort Wayne Railroad Bridge, listed as the Pennsylvania Railroad Bridge on the National Register of Historic Places, is a double-deck steel truss railroad bridge spanning the Allegheny River in Pittsburgh, Pennsylvania.

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Image may contain: sky, bridge and outdoor

 

Image may contain: bridge, sky, outdoor and water

Image may contain: sky, bridge and outdoor

Image may contain: bridge, sky, plant and outdoor               Image may contain: sky, bridge and outdoor

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source:PghHistoryCenter

Pittsburgh Steel Industry

Pittsburgh was named in 1758 by General John Forbes, in honor of British statesman William Pitt, 1st Earl of Chatham.

Tʜᴇ ᴍᴀss-ᴘʀᴏᴅᴜᴄᴛɪᴏɴ ᴏꜰ ᴄʜᴇᴀᴘ sᴛᴇᴇʟ ᴏɴʟʏ ʙᴇᴄᴀᴍᴇ ᴘᴏssɪʙʟᴇ ᴀꜰᴛᴇʀ ᴛʜᴇ ɪɴᴛʀᴏᴅᴜᴄᴛɪᴏɴ ᴏꜰ ᴛʜᴇ Bᴇssᴇᴍᴇʀ ᴘʀᴏᴄᴇss, ɴᴀᴍᴇᴅ ᴀꜰᴛᴇʀ ɪᴛs ʙʀɪʟʟɪᴀɴᴛ ɪɴᴠᴇɴᴛᴏʀ, ᴛʜᴇ Bʀɪᴛɪsʜ ᴍᴇᴛᴀʟʟᴜʀɢɪsᴛ Sɪʀ Hᴇɴʀʏ Bᴇssᴇᴍᴇʀ (1813- 1898).

 The Bessemer process, created independently by Henry Bessemer in England and William Kelly in the United States during the 1850s, allowed the mass production of low-cost steel; the open-hearth process, first introduced in the United States in 1888, made it easier to use domestic iron ores.

A milestone in steel production was achieved in 1875, when 𝑻𝒉𝒆 𝑬𝒅𝒈𝒂𝒓 𝑻𝒉𝒐𝒎𝒔𝒐𝒏 𝑾𝒐𝒓𝒌𝒔 𝒊𝒏 𝑩𝒓𝒂𝒅𝒅𝒐𝒄𝒌 began to make steel rail using the new Bessemer process. Industrialists such as Andrew Carnegie, Henry Clay Frick, Andrew W. Mellon, and Charles M. Schwab built their fortunes in Pittsburgh.

 From 1875 to 1980, southwestern Pennsylvania was the Steel Making Capital of the World, producing the steel for some of America’s greatest icons such as the Brooklyn Bridge and the Empire State Building.
Andrew Carnegie, from Scotland, a former Pennsylvania Railroad executive turned steel magnate, founded 𝐓𝐡𝐞 𝐂𝐚𝐫𝐧𝐞𝐠𝐢𝐞 𝐒𝐭𝐞𝐞𝐥 𝐂𝐨𝐦𝐩𝐚𝐧𝐲. He proceeded to play a key role in the development of the U.S. steel industry. The Carnegie Steel Company, which he sold to J.P. Morgan in 1901 for $492 million. It became the U.S. Steel Corporation.
J. P. Morgan and attorney Elbert H. Gary founded U.S. Steel on March 2, 1901 (incorporated on February 25) by combining Andrew Carnegie’s Carnegie Steel Company with Gary’s Federal Steel Company and William Henry “Judge” Moore’s National Steel Company for $492 million ($14.16 billion today).

By the early 1900s, Pittsburgh was producing around half of the United States’ steel.

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Created by Congress in 1996, the Rivers of Steel National Heritage Area is committed to preserving, interpreting, and managing the historic, cultural, and natural resources related to Big Steel and its related industries.

 

Encompassing over 5,000 square miles in the eight counties of Allegheny, Armstrong, Beaver, Butler, Greene, Fayette, Washington, and Westmoreland, Rivers of Steel is building on this area’s remarkable transition from heavy industry to high technology and diversified services as well as bolstering the new regional economy by promoting tourism and economic development based on this region’s historic industrial saga.

Pittsburgh has always been well known for being the “𝓢𝓽𝓮𝓮𝓵 𝓒𝓲𝓽𝔂,” even its professional football team earned its moniker the Pittsburgh Steelers from the large steel production.

Today Pittsburgh has adapted to the changing economy, reinventing itself and shifting to a service-based one instead. medicine, education, technology, and banking now drive Pittsburgh’s economy.

 

source:PghHistoryCenter

Continue reading “Pittsburgh Steel Industry”

The Carrie Blast Furnaces

The Carrie Furnaces were built in 1881 as part of U.S. Steel’s Homestead Works, a sprawling 400-acre complex that spanned both sides of the Monongahela river.

They produced up to 1,250 tons of steel a day until 1978 when they were closed.

The 100-foot high furnaces still stand; now they are an extremely rare example of pre-WWII ironmaking technology.

The furnaces were designated as a national historic landmark in 2006 and preservation.

Rust Belt Recovery

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From 1875 to 1980, southwestern Pennsylvania was the Steel Making Capital of the World, producing the steel for some of America’s greatest icons such as the Brooklyn Bridge and the Empire State Building.

Created by Congress in 1996, the Rivers of Steel National Heritage Area is committed to preserving, interpreting, and managing the historic, cultural, and natural resources related to Big Steel and its related industries.

Encompassing over 5,000 square miles in the eight counties of Allegheny, Armstrong, Beaver, Butler, Greene, Fayette, Washington, and Westmoreland, Rivers of Steel is building on this area’s remarkable transition from heavy industry to high technology and diversified services as well as bolstering the new regional economy by promoting tourism and economic development based on this region’s historic industrial saga.

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Guided tours

Rivers of Steel National Heritage Area is operating guided tours of the Carrie Blast Furnaces.

Constructed in 1906, Carrie Furnaces 6 and 7 stood at the heart of U.S. Steel’s Homestead Works until 1979.

At one time, the furnaces and the steelworkers who labored in them produced more than 1,000 tons of iron a day. Now these 92-foot-tall structures stand as sentinels to Pittsburgh’s steel heritage.

On this tour, a Rivers of Steel tour guide will lead visitors through the iron-making process, sharing the story of the site’s technology, workers, and culture from it’s heyday to the post-industrial present.

Rivers of Steel National Heritage Area
The Bost Building
623 E. Eighth Avenue
Homestead, PA 15120

 

source:Ameristeeljournal

Sheet Metal Fabrication

Metal Shaping

Metal Shaping or forming can only change metal in four ways. You can bend, cut, shrink and stretch metal to form it.

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Metal Fusion

Sheet metal fabrication is fusing small panels together to produce larger complex parts. The most common type of metal fusion is welding.

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Bending Metal

Form Bending- This is the simplest way to bend metal. It can be shaped or bent with a hammer.

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Metal Brake- A metal brake will make clean, precise bends in metal and works by placing the metal on a flat, gated surface and then clamping a flat bar on top of the metal and lifting the gated portion to bend the metal to the desired angle.

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Cutting Metal

Hand Shears- Hand shears are a manual, way to cut metal. Snips or hand shears are one first tools need when working with metal fabrication.

Power Shears- Power shears are for cutting metal. They cut sheet metal more quickly and with less manual effort.

Throatless Shears- Hand operated and use a hinged blade that swings down and cuts the metal that’s lying on a stationary adjacent blade. Designed to allow you to cut metal in straight lines or shapes in sheet metal with no marring of the cut edge.

Angle Grinder-  Uses a disc or wheel at a fast rate of speed for removing material in a quick manner. Thin cutting discs are available for cutting metal.  Cuts through multiple layers of sheet metal.

Plasma Cutter- Plasma cutter can cut sheet metal quickly with extreme accuracy and minimal clean up. This will make long straight cuts that may be difficult to handle alone on a throatless shear.

 

Shrinking Metal

Tucking Metal- This is a method of shrinking metal. Bunch the metal together by forcing it between a crevice with a spade hammer or by folding the metal over at the edges with a homemade tucking fork.

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Shrinker- A lever-operated tool (hand or foot) that has moving textured jaws that grasp sheet metal from the top and the bottom and force it together tightly. This method is a lot more precise than tucking with a hammer and form, but moves the metal much slower. You can carefully work particular areas to shrink them as desired.

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Heat Shrinking- The type or amount of stretched metal determines how you shrink or smooth the area out. compressed air can be used to get the desired shrink.  A shrinking disc can be attached to an angle grinder for precise friction to create the heat.

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Stretching Metal

Air hammer- Firmly hold an object behind the metal and hit the other side with a hammer. This forces the metal to be compressed and ultimately stretch.

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Stretcher–  A mechanically operated tool that puts the metal between two flat textured jaws and pulls the metal apart slowly each time the lever or foot pedal is pressed.

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Sheet metal thickness is measured in gauges, with a higher number indicating a thinner sheet. To measure the thickness, you can use a sheet metal gauge.

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source:MetalMarketInc

General Contractor Terms

Bid

A bid can mean that you are offering to do work for a particular price or that someone is offering to pay a particular price for someone’s work. In the construction industry, a bid is a document that a general contractor gives to a potential client that shows how much he will charge to do the work. The word “bid” can also refer to the actual dollar amount in the document.

A bid is created when the scope of the work is clearly defined by the client. Often a bid is given when the client is accepting offers from several general contractors.

In addition, subcontractors present bids to general contractors in order to win their specific projects. Their bid will go into the general contractor’s main bid that is given to the client.

Estimate

An estimate is an approximate rough figure that a general contractor gives to a client. The number is based on less clear data and limited information. Estimates are usually done for free in order for the client to get an understanding of roughly how much things will cost. This can help you determine if a certain general contractor is within your budget.

The price wont stay exactly the same once more details about the project are given to the contractor. The price could go up or down but the contractor is not legally bound to keep the price the same.

Proposal

A proposal is much more detailed than a bid or an estimate. It is a document  that outlines the exact scope of the project, materials used, and the costs. Like a bid, it can also be competitive. It will include bids from subcontractors, raw materials costs, labor costs, taxes, and the contractor’s mark-up. It will show you when your general contractor expects payments.

Often, a proposal can turn into a contract when the client signs it or there may be a place to sign to acknowledge receipt of the proposal. Either way, once accepted, this is the closest to actually starting the project.

Quote

A quote is similar to an estimate. It is non-binding until a contract is signed and it is usually based on a specific time frame. For example, you won’t be able to receive a quote from a general contractor and come back a year later expecting the same price.

A quote can also refer to a dollar amount that a contractor receives from a material supplier or other vendor. A general contractor will use the quote that is given in the estimate, bid, or proposal. This is why there is a time frame associated with these documents – because material costs are a commodity and they will fluctuate from month to month. If a general contractor gives a bid, estimate, or proposal based on the cost of goods one month the project is not moved forward for some months ahead, the material costs could have changed dramatically. A new document will need to be drafted to reflect current costs.

 

source:SteelTown/US/stus