7.1 Equipment Used in the Construction Industry

Douglas Rupik, M.Ed., JIW

Two workers are silhouetted as they work on the steel frame of a building, with other highrises in the background.
Figure 7.1. Building Highrises Requires Working At Heights / Photo Credit: Carol M Highsmith, CC0

About 10% of welders work in the construction industry (Welder Demographics and Statistics, n.d.). Examples of building/construction trades that are commonly associated with welding are Ironworkers, pipefitters/steamfitters/sprinkler fitters/plumbers, piledrivers, millwrights, and boilermakers. Other building/construction trades may also use welding in the scope of their work. If you pursue a career in construction, you will likely work in all types of weather and have to travel. After a time, you will be able to point to different structures and proudly say, “I built that!” Besides working in different types of weather and traveling to different job sites, perhaps what distinguishes a construction welder from a shop welder is the size of the object they are working on. Bridges and buildings are large. The parts used to build them are large, which means many of the tools used to assemble them are large. Your first time on a construction job site may be intimidating, so let’s discuss some of the equipment you may see.

Specialized tools used in the field

While an experienced shop fabricator can easily transition into the field welder role, some tools may be new or unfamiliar. Often, welding in the field requires a gas or diesel-powered welder generator rather than a welding machine that plugs into a wall outlet (110v/220v/480v). Flux core welding will likely be performed with a voltage-sensing “suitcase” wire feeder. This gets its operating power from the welding current and requires its own ground on the workpiece. Flux core welding outside will often be performed with high deposition, self-shielding wire electrodes.

A welder in a high visibility vest with a hard hat-mounted welding hood welds on trusses.
Figure 7.2. A Welder In The Field Often Has To Wear A Welding Hood Mounted On Their Hardhat. / Photo Credit: U.S. Army Corps of Engineers, PD

Working in the field will require you to wear your welding hood over a hard hat using special headgear. When working at heights, you may also be required to wear a chinstrap to prevent you from dropping your hood and hard hat onto unsuspecting people below. Of course, you will be required to use fall protection that is either engineered (such as guardrails and scaffolding) or a personal fall arrest system, such as a harness with a lanyard or retractable lifeline.

If working outside, you will be exposed to the elements. Dress appropriately for the weather with cotton, wool, or other natural fibers. You may find yourself working in the rain, under an umbrella, wearing rain gear. This is definitely something that must be taken into account when deciding on a career path.

A welder perches on the side of a bridge and welds with one hand, holding onto the bridge with the other hand.
Figure 7.3. Welding In The Field Often Requires In All Types Of Weather And Working Conditions Very Different From In A Shop. / Photo Credit: City of Greenville, North Carolina, PDM 1.0

Hoisting and Lifting Equipment

Moving large building materials has been a problem since ancient times. The ancient pyramids in Egypt, the Americas, and Asia, the statues of Easter Island, and Stonehenge in England all were constructed of stone blocks weighing up to several tons each. We still are not entirely sure of the exact methods used to hoist) or lift and transport the largest of these blocks. We do know that wooden cranes powered by people in giant “hamster wheels” were used in ancient Rome and the Middle Ages in Europe.

A wooden crane with a large wheel on one side sits in the middle of a field of grass.
Figure 7.4. Medieval Style Crane / Photo Credit: Ji-Elle, PD

Modern cranes use a similar basic idea, minus the hamster wheel, but are much larger and capable of handling greater weights than their wooden ancestors.

Different sizes of construction projects require different sizes of cranes, and there are some design differences as well.

A large tower crane lifts a large load to the building under construction next to it.
Figure 7.5. Tower Cranes Are Used To Lift Large Loads / Photo Credit: NASA, PD
A red lattice boom crane mounted on crawler treads lifts precast tilt-up concrete panels into place on a construction site.
Figure 7.6. Crawler Mounted Lattice Boom Cranes Are Used On job sites Requiring High Capacity Cranes That Can Move Around The job site. / Photo Credit: NASA, PD

Cranes with lattice booms mounted on crawler treads (like tank treads) or railroad tracks, or tower cranes, are the cranes most likely to be used on the largest of job sites, due to their greater capacity and reach, both in height and radius (distance they are able to reach away from where they are parked). Many of these cranes must be trucked to a job site in pieces and assembled over days or weeks before they are ready to be used.

Other cranes have hydraulically telescoping booms and are based on vehicles that can travel on the highway (boom trucks) or have large off-road tires and are capable of all-terrain travel. These may be able to perform lifting on their tires or, for a greater capacity, on outriggers that stabilize the crane. Their sizes range from just large enough to move a load from the ground to the roof of a single-story building to over 100 feet high.

While operating and working with a crane rigging loads may look simple, cranes are dangerous pieces of equipment that require thorough training to use safely. National certifications for operators, signal persons, and riggers require extensive written and practical tests.

As stated in the chapter on equipment safety, hoisting equipment lifts loads from above. Cranes are a type of hoist. Other hoists you may use are winches and chainfalls. (NEVER USE A COME-ALONG AS A LIFTING DEVICE. THEY ARE ONLY INTENDED FOR LATERAL PULLING!). Hoists may be secured to an overhead part of the structure you are working on or suspended from a frame called a gantry. Be sure your anchor point is capable of supporting the load.

A yellow forklift with its forks raised.
Figure 7.7. Typical Forklift / Photo Credit: Compliance and Safety LLC, CC BY-SA 3.0
A forklift moves a pallet load of material to a shelf high overhead in a warehouse.
Figure 7.8. Forklift In A Warehouse / Photo Credit: U.S. Department of Agriculture, PD

Forklifts are lifting equipment. They may be a warehouse-type forklift with a vertical mast, or they may be a forklift with a telescoping boom. Again, these are so commonly seen that people often become complacent around them regarding safety. Training is required for safe operation. Forklifts with telescoping booms tend to be more complicated to operate than warehouse forklifts due to the additional functions they are capable of. They can raise and lower a load and extend it horizontally away from the cab. These forklifts are often all-terrain with large tires, can tilt their chassis, and can have four-wheel steering that can be operated independently between front and rear axles. Some can also pivot their forks from side to side. All of these controls require training and practice for safe operation.

There are also smaller lifting devices called hand lifts that are powered by hand cranks or winches. These resemble the mast and forks of a warehouse forklift, but instead of possessing a cab with a seat, engine and counterweight, they simply have a hand-cranked winch. These typically have a maximum capacity of a few hundred pounds but are small enough to fit through a doorway.

Lengths of pipe are easily moved with a manual lifting device known as a “grasshopper” pipe dolly. Drywall carts, pallet jacks, piano carts, and hand trucks or dollies are often used to move materials in places that a forklift cannot access. Obviously, construction work requires a certain level of physical strength and fitness.

Aerial Lifts and Platforms

A construction worker welds steel building connections while standing in an aerial work platform.
Figure 7.9. Aerial Lifts Are Used To Allow Workers To Gain Access To Work That Cannot Be Reached By Ladder / Photo Credit: City of Greenville, North Carolina, PDM 1.0

Once the structure you are working on becomes taller than you can reach, you have a problem. Drywall finishers have solved this by wearing stilts on the job. I have yet to meet a welder who is interested in trying this. Using a ladder can get you in the air, but your reach is limited, and climbing up and down a ladder, moving it constantly, is much less productive than working with both feet on the ground.

Consider the Depression-era photo of ironworkers eating their lunch, seated on a beam hundreds of feet in the air. Safety and the ability to access your work have come a long way since the 1930s. Today, we have hard hats, fall arrest harnesses, aerial lifts, and work platforms, which make work safer and increase worker productivity.

Several construction workers are seated on a beam high atop a skyscraper, chatting while eating lunch.
Figure 7.10. Lunch Atop A Skyscraper, 1932 / Photo Credit: Charles Clyde Ebbets, PD

Modern aerial lifts typically have a heavy counterweight base with a telescoping boom. At the end of the boom is a basket or platform surrounded by a railing with space for two workers. Controls are normally operated from the basket, with a second set of controls at the base on the ground. These lifts can have a straight boom or different joint configurations to allow them to work around obstructions like pipes. They can be all-terrain with independent front-rear steering and be diesel, electric, or gas/propane powered. Proper training is required for the safe use of aerial lifts. ALWAYS WEAR A FALL ARREST HARNESS AND KEEP YOUR LANYARD ATTACHED TO THE PROPER ANCHOR POINT IN THE BASKET AT ALL TIMES! Some of these boom lift aerial work platforms can reach over 125 feet in height.

Two construction workers stand in a scissor lift that is raised off the ground. One of the workers is performing hot work on a girder, and sparks fill the air.
Figure 7.11. Scissor Lift In Use / Photo Credit: MTA Construction & Development Mega Projects, CC BY 2.0

Platforms can be motorized, such as a scissor-type lift, or they can be scaffolding. Vertical lifts can range in size from a one-person vertical lift (similar to working from the top of a telescoping car antenna) to a multi-person, all-terrain behemoth driven by an internal combustion engine. Probably the most common size lift accommodates two people, can fit through a doorway, and runs on rechargeable batteries. Remember to plug these in for recharging at the end of your shift. Dead batteries in your lift make for an irate foreman and a long day at work the next day.

Stairs mounted inside scaffolding are installed next to a building under construction.
Figure 7.12. Stair Tower Outside Of A Building / Photo Credit: Marcel Schoenhardt, CC BY-SA 2.0

Scaffolding can be stationary, attached to the outside of a building, and reach dozens of stories in the air, or it can be a smaller, wheeled unit that fits through a doorway.

Two workers are in a swing stage platform hanging outside a building.
Figure 7.13. A Swing Stage Is Often Used By Window Washers Or Construction Workers To Access The Outside Of Buildings / Photo Credit: Dmitry Ivanov, CC BY-SA 3.0

A “swing stage” is a type of scaffolding that is suspended by wire ropes (cables) and can move up and down, usually powered by an electric motor. Window washers typically use this type of platform on the outside of high-rise buildings. The davits (arms) which the swing stage hangs from may be permanently attached or have a temporary anchoring system held in place by weights. Always refer to the manufacturer’s recommendations regarding how much counterweight is to be used for the load on the platform, and always inspect the davits before each use. My instructor related how he and his coworker were returning to work after lunch to discover roofers had begun to disassemble and move the supporting arms and counterweights in order to perform their work on the roof. Had my instructor simply hopped back in the swing stage on the ground and started to try ascending, they would have pulled the supporting arms off the roof, and they would have fallen on them. If you are welding from a swing stage, be aware of two things. First, you may find yourself swaying while you weld, which will require you to learn how to steady yourself with one hand while you weld using the other. Second, your electrode and stinger may short (ground) themselves out on the swing stage platform while the building you are working on is the electrical ground. In this situation, you may get shocked if you touch the building. This is yet another reason you should remove stick electrodes from the holder when not actively welding. Of course, there must always be a safety line independent from the swing stage platform, with which you should always have your personal fall arrest harness attached.

You may be fortunate enough to work on a variation of the swing stage called the bosun’s chair, a single seat suspended by a single line. There is also the float: a plywood platform suspended by rope or an even smaller contraption called an “angel wing.” You can imagine what working from any of these is like.

A construction welder stands atop a beam in a building under construction.
Figure 7.14. Ironworker Welder / Photo Credit: Doug Rupik, CC BY 4.0

Earthmoving Equipment

Many of us had toy dump trucks when we were children, and surely all of us have played in the sand or dirt, digging and building miniature cities and landscapes. On a construction site, you will get to see the real thing in action. You may even have a job doing repair welding on some of this equipment. Earthmoving equipment can be divided into two categories: digging and hauling.

Some excavating or digging equipment examples are track hoes, front end loaders, backhoe/loaders, trenchers, graders, bulldozers, and scrapers.

An excavator, sometimes called a track hoe, may come to mind first when discussing digging equipment. This piece of equipment has crawler or “tank’’ tracks with a cab that spins around and a long articulated boom arm. The end of this arm will be fitted with digging accessories such as a bucket, jackhammer, or grabbing claw. These are particularly good at digging deep holes with steep sides, such as basements and foundations for buildings. The arm allows a long reach away and lower than the cab, and the fact it rotates allows it to grab a bucket of earth and immediately load it or pile it away from the hole it is digging.

A front-end loader has a large blade or bucket across the front that is used to scoop up large loads of dirt or gravel. A backhoe loader tractor is a combination excavator and front end loader mounted on a common farmer-style tractor.

A trencher resembles a truck or tractor with a giant chainsaw sticking out of the front or back. This “chainsaw” cuts a narrow trench into the ground for pipelines or other utilities.

Graders look like long, skinny tractors with giant blades across their midsection. They are used in leveling ground, particularly in road construction. Scrapers are used for the same function, except they will also remove dirt from the area.

Bulldozers are heavy-duty, track-mounted trucks that are used to move dirt and gravel. They have a blade mounted to the front used for leveling and moving anything in its path.

Hauling equipment includes front end loaders and dump trucks in various configurations. Front end loaders do just that: they scoop up large loads of earth and lift them into the air to load into trucks. Dump trucks may be single units or have trailers. They may also be small enough to travel on public roads or be massive units that may only do work in mining operations.

As a welder, you may be working in excavations, welding pipes, or pilings, or you may be performing repair work on these pieces of equipment.

If working in an excavation, be sure proper shoring is being used. You may have seen large metal plates lining trenches. These are kept apart by pipe spacers and prevent the trench walls from collapsing. Workers can be quickly killed if the sides of the hole collapse or cave in.

You may also perform hardfacing welding on digging equipment. Often, weld metal is deposited on digging buckets or dozer blades to slow down wear or replace worn metal. This weld metal is harder than the base metal and is often welded in a cross-hatch pattern to provide abrasion resistance. If performing other repair welding on heavy equipment, be sure to use proper lockout tagout procedures (see Chapter 2).

Attributions

  1. Figure 7.1: Restoration work on Reading Terminal by Carol M Highsmith is released under CC0
  2. Figure 7.2: Work progresses at National Air Force Museum by U.S. Army Corps of Engineers in the Public Domain; United States government work
  3. Figure 7.3: Town Common Pedestrian Bridge by City of Greenville, North Carolina is released under PDM 1.0
  4. Figure 7.4: Grue médiévale (reconstituée) devant l’abbaye de Hambye (Normandie) by Ji-Elle in the Public Domain; Public Domain dedication, not CC0
  5. Figure 7.5: A crane and rigging are used to lift the Orion Service Module Umbilical (OSMU) high up for installation on the mobile launcher tower at NASA’s Kennedy Space Center in Florida. by NASA in the Public Domain; United States government work
  6. Figure 7.6: In Launch Complex 39 at NASA’s Kennedy Space Center in Florida, workers guide one of the walls of the Propellants North Administrative and Maintenance Facility into place. by NASA in the Public Domain; United States government work
  7. Figure 7.7: Forklift-Truck by Compliance and Safety LLC is released under CC BY-SA 3.0
  8. Figure 7.8: 20180912-FNS-PJK-0699_TONED by U.S. Department of Agriculture in the Public Domain; United States government work
  9. Figure 7.9: Aerial lifts are used to allow workers to gain access to work that cannot be reached by ladder. by City of Greenville, North Carolina is released under PDM 1.0
  10. Figure 7.10: Lunch atop a Skyscraper – Charles Clyde Ebbets by Charles Clyde Ebbets in the Public Domain; This work is in the public domain because it was published in the United States between 1928 and 1963, and although there may or may not have been a copyright notice, the copyright was not renewed.
  11. Figure 7.11: Ironworkers are welding a column in the back-of-house area of the future LIRR passenger concourse. (CM014B, 05-22-2019) (47952892561) by MTA Construction & Development Mega Projects is released under CC BY 2.0
  12. Figure 7.12: Construction Update – Mayfair South by Marcel Schoenhardt is released under CC BY-SA 2.0
  13. Figure 7.13: Workers on suspended scaffold in Korolyov by Dmitry Ivanov is released under CC BY-SA 3.0
  14. Figure 7.14: Ironworker Welder by Doug Rupik, for WA Open ProfTech, © SBCTC, CC BY 4.0
definition

License

Icon for the Creative Commons Attribution 4.0 International License

Introduction to Welding Copyright © by Washington State Board for Community and Technical Colleges is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.