Metal fabrication is a broad term that includes any process that shapes, cuts or mould metal materials to produce a final product. Manufacturing technology has gradually been evolving, along with the metal fabrication industry. While hundreds of classic fabrication tools, strategies and techniques have become obsolete, new technologies are completely reshaping the way metal is fabricated in various industries.
The structural steel fabricator has developed into a lean, mean machine, but automation in this industry has a long and interesting history. Most structural fabrication operations of the past were labour-intensive. Layout, drilling, cutting, and welding were performed manually. In structural fabrication today, nearly every process can be automated. Few if any other metal manufacturing sectors could make such a claim.
The ’70s and ’80s
Structural fabricators stepped into beamline automation with machines like the Beatty punch, followed by the three- and five-press beam punch lines. The beam punch lines of the 1970s were the first step. They reduced the manual labour required to process main structural members by punching the holes in all surfaces in one pass. A saw could be added on the same system to cut members to length.
The next progression was the “pop mark,” an early way for a beam punch line to make layout marks on a beam. Using the tip of the punch, a machine could mark the centre point of the piece and the intersection for weldments, plate, and angle connection points.
Dealing with mill tolerances was the next challenge to overcome for machines of the late 1970s and early 1980s. Machines had to be designed to detect all the conditions of the piece to be processed. This included toed-in or -out flanges, off-centre webs, twist, and camber.
The structural drilling and sawing line was the next development, and in the early 1980s drills were quickly replacing the beam punch lines of the past. The weight and thickness restrictions of material diminished, paving the way forward.
In some cases, though, the beam punch line was even faster on lighter material. There was a saying at one time: Punch for profit, drill for oil. The saying was true; the cost per punched hole was considerably cheaper than the cost per drilled hole, although this did not offset the total benefits of drilling. The punching system was not as flexible as the drill, and the punch had restrictions based on the punching tonnage available.
Early automated copying machines of the mid-1980s were simple systems with no linear measuring that could prepare basic end-connection detail using three oxyfuel torches.
The next generation of copying machines could produce far more complex cuts such as copes, notches, rat holes, weld preparation, slots, web penetrations, split tees, and castellated beams, to name a few.
By the late 1980s, downloading of data from 3-D CAD systems became a reality. The basic cut-to-length, hole position, pop marks for part location, piece number, and cope information was held in the DSTV file format, which was developed in Germany and became a global standard. Many versions later, this format is still used today, but the file holds far more information.
In the 1990s, the cold saw was phased out at many plants and replaced with more cost-effective methods, such as band sawing. Typically, the band saws were placed in tandem with the drill; this saved space and required only one operator. The CNC positioned both the saw and the drill before transferring the beam to a copying machine.
The industry soon witnessed the evolution of plate processing. Structural fabricators moved from the traditional burn table with multiple oxyfuel torches to a pass-through-style system in which the material moved, and the machine remained fixed. Such combination systems could either punch and plasma cut or punch, drill, and plasma cut. The oxyfuel torch was retained on certain models for thick materials.
The pass-through systems used nesting programs to minimize scrap. They also dropped off the finished part rather than requiring an operator to remove it from a table or shake it from a skeleton. The “stock material on, part of” concept revolutionized plate production, especially in structural steel shops. Along with downloading data from CAD, this concept allowed structural fabricators to produce standard parts. This reduced plate inventory and allowed designers to work with certain design parameters to create standard connections. All this boosted fabrication efficiency.
During the 1990s the industry began to notice the obvious constraints of material handling. They included the labour cost associated with moving steel through processing to fabrication and ultimately getting the correct detail parts (that is, those parts to be connected to beams) to the weld stations.
Many different material handling methods were used. Workers sometimes pushed beams on simple trolleys from station to station. Sometimes they operated a motorized system capable of positioning multiple beams at one time for each station.
It was estimated a fabricator touched a beam up to 15 times at an approximate cost of $25 per lift. For this reason, material handling became a huge focus for the fabricator to reduce labour-hours and cost.
By 1998 the industry witnessed early automated material handling technology that loaded and unloaded a simple drill-saw tandem system. Fabricators in North America began to see hydraulically driven rollers and transfer systems. These hydraulic systems required an operator at each processing position, so they had high labour costs. The hydraulic system is still widely used today but is being phased out.
Enter the MSI
Today’s automated systems—known as multisystem integration, or MSI— position workpieces using electric motors, inverters, and encoders. Monitoring the position of each piece, the MSI combines multiple machines into one production line. Once the production requirement is created, and material is loaded, an MSI operates without manual input.
For example, material moves from a shot blasting machine to a drill machine, a layout marking machine, a sawing machine, and finally a plasma and oxyfuel robotic structural cutting system. Roller conveyors and cross transport mechanically connect all machines.
The production process starts at the detailing office, where the project is created in a 3-D CAD system. Each product is broken down into a DSTV file that is then imported into the machine’s software. After this step, nested files are generated in a DSTV+ format, which is then uploaded to the master control of one of the machines. The product is then distributed from the master to all machines in the production line. Because every machine is connected to the master, each one always has the most up-to-date production data available.
Today the operator simply selects the loaded profiles on the control panel and starts the process. Data then is updated automatically at the production office and every machine. The material handling system has built-in buffers, so the production line knows the order in which the beams go through and which processes are required on each piece.
Cross transports with photocells detect the profiles and position them at the correct distance apart for the shot blasting of multiple pieces in one pass. Immediately after processing, transfer mechanisms move the beams to the next operation. Encoders and sensors in the roller conveyor register the exact position of the batch. When the sensor on the infeed control is passed, a new batch of beams is transported onto the infeed conveyor. The new batch holds the position until the first bundle passes the outfeed sensor. The height of the beams is monitored to ensure the dimensions comply with the data in the software, and the height of the brush and blowoff unit is adjusted to remove any blast media from the web area before the beam moves to the next operation.
Cross transports between two machines function as a buffer to equalize differences in production speed. Beams on the cross transports are automatically repositioned to create enough space for the next bundle of beams. The software knows the beam positions and dimensions to ensure all operations connect seamlessly to each other—and all of this is followed in real-time by the production office.
Mechanical drag-dogs move beams rapidly over the cross transports to minimize transfer time between machines. Before the beam crosses the infeed roller conveyor, the feed slows as it approaches the datum line to prevent damage.
A servo-driven feeder truck moves the beam, and at the same moment, the roller conveyor moves the beam toward the servo-driven feeder truck. This also reduces the transfer time. The beam is then processed while the next beam is transferred close to the infeed roller conveyor.
Short pieces (less than 47 in. long, for example) are removed and pushed sideways into a bin by a short product removal system. Leading and trailing edge trim cuts are removed and deposited in the scrap bin with no manual intervention. Finally, the long pieces are transported to the outfeed cross transports and are removed.
Enter Welding Automation
The next step, now a reality but still in the early stages of adoption, is adding robotics to the structural fabrication shop. Robotic welding and thermal cutting are not new to structural fabricators, but automated welding is—that is, welding with no manual intervention whatsoever. This includes program development and moving material in and out of rotating fixtures.
Two technology advancements make fully automated robotic welding possible. First, weld programming in these systems now can be automated. Traditionally, robotic welding systems still require programming, so a structural fabricator usually takes a welder and makes him a programmer. But the goal is to reduce overhead and increase efficiency, not increase the labour burden.
Second, robots use sensors and probes (including the use of the welding wire tip as a touch probe) to measure and adapt to workpiece variation. For instance, intelligent systems now can probe toed-in or -out flanges, off-centre webs, and whether the material is within mill tolerances.
Intelligent welding systems can import data from CAD if the welding information is in the model. If it is not, a database can recommend the welding information to add to the model; a programmer then can take this recommendation or add in the welding information separately.
At the end of the beamline, beams are automatically loaded into the welding system. From here the detail (that is, the part to be welded onto the beam) is transported, deburred, scanned, and positioned correctly so that the material handling robot can place the part on the beam. Using the wire tip as a touch probe, the welding robot detects the beam’s true position, then tacks the part. Finally, when all the parts are tacked in position, the robot arm welds the pieces.
Let’s have a look at the most disruptive technologies that can have a huge impact on the metal fabrication industry:
Automation has completely revolutionized the way products are manufactured and handled. Advanced automation systems and robotics are being increasingly implemented across manufacturing industries to accelerate production processes and boost productivity. Human workers can’t work 24/7 and maintain the quality of the production process. Robots, on the other hand, completely outsmart human employees in terms of speed, precision, and performing repetitive tasks with great ease. The day is not far when machines will take over and run the entire fabrication facility without any human intervention.
3D printing is a relatively new technology that has had a major impact on the manufacturing industry. It can be used to redesign materials like plastic, concrete, steel, and even masonry. 3D printers are growing in size and capacity following the high demand for innovative products. It is possible now to create and assemble an entire building using 3D printing methods. 3D printing has a disruptive impact on fabrication due to its ability to alter how parts are developed, maintained, and ordered. It can also help fabricators reduce waste and optimize energy usage.
Lower dependency on steel
Most modern machining techniques have been developed for materials that are difficult to machine. Some of the modern fabrication methods are designed to produce complex shapes and cavities. While electrical discharge processes are limited to metals, ultrasonic machining can be applied to fabricate a broad range of materials: silicon, ferrite, ceramics, glass, germanium, etc. The development of the latest fabrication solutions will open up possibilities for diverse use of materials.
With more advanced fabrication practices, manufacturers can utilize innovative materials and lower their dependency on steel. Additive manufacturing and material sciences have made it possible to fabricate materials, which would hitherto have been impractical.
Definition Of Fabrication Technology
It is defined as a different field of engineering involves joining together quite no. of the smaller component in structural construction machine, building etc. this component can be joined by temporary fastening like bolts, screws, but joining them permanently involves the use of forging, riveting and welding techniques.
Importance Of Fabrication Technology
Mainly all critical structures are produced by fabrication technology like boiler, pressure vessel, ships, offshore, structure, bridges, storage tanks, rocket parts, sphere etc. are produced speedily, easily and economically.
- Thermal and nuclear power plant
- Oil pipeline construction
- Process plant
- Automobile industry
- Aerospace industry
- Bridges construction
Ways Automation is Enhancing Industrial Steel Fabrication
Greater precision in steel products
One of the many advantages that automated fabrication technology has over manual fabrication is that weldments, bends and cuts can all be completed with greater precision and accuracy.
This is because of machines complete work with less variability than human labour.
Completing fabrication projects with greater precision means that the likelihood of having to do re-work is eliminated, which is not only costly but can slow down project completion timelines.
This greater precision also enhances the quality of the project as automated fabrication machinery performs all tasks precisely and consistently to exact measurement specifications.
One of the biggest ways in which automated fabrication technology creates better steel fabrication outcomes is by enhancing efficiency.
This is due to:
- Less time needed to complete work (up to 2 or 3 times less in most case studies), leaving fabricators time to spend time completing adjacent work, which leads to sped-up project timelines
- Shorter lead times, which allows fabricators to complete multiple projects on-site, whether for the same or multiple stakeholders
One of many examples of automated fabrication machinery, which greatly enhances project efficiency is beamline technology.
Beamline technology works to speed up the cutting and drilling of steel beams, instead of fabrication professionals manually measuring, cutting, and drilling steel beams – a time-consuming process.
Not only do beamlines enhance efficiency by speeding up the process, but they also increase safety for workers as it requires the steel beam to be moved less by workers.
For more complex heavy fabrication projects, a single component may need to be moved multiple times for all the necessary work to be completed, often requiring the use of overhead cranes.
Since the nature of heavy fabrication projects means they are large-scale, there is a risk each time the structure is moved.
More controlled processes and predictable life cycles
Automated fabrication technology and machinery help to control fabrication processes and create more predictable life cycle times.
A more predictable life cycle allows fabrication companies to deliver finished projects on time and schedule fabrication professionals more accurately.
Examples of controlled automated fabrication processes include
- Precision machining
- Automated cutting
Since automated fabrication processes are machine-run, they aren’t prone to human error which can slow down production due to re-work.
This allows Fabrication Plant Managers to more accurately plan life cycles, improving project flow, scheduling and accuracy.
Enhanced data and reporting
When automated fabrication technology is paired and connected with software, it becomes a wealthy resource to identify mistakes in weldments and log valuable data for future reporting.
This data can give metal fabrication companies better insight and accuracy into processing times, which in turn can be passed over to the customer in the form of more accurate scheduling quotes.
This data is also useful in quickly identifying quality control issues so they can be mitigated before a project’s inspection date, where re-work may be identified, and project completion timelines are extended.
One of the greatest benefits of automated fabrication systems and robotic technology is that it can increase safety for workers.
This is due to the reduced need for large fabricated modules to be moved manually, leaving less chance for human error leading to safety incidents.
While automated machinery is helping enhance safety for shop workers, the need for skilled fabrication workers isn’t dwindling.
While robotic welding machines are used for specific, repetitive tasks, such as bending and cutting, the need for versatile welders and fitters isn’t fading anytime soon. There is still a growing need for welding professionals in the industrial fabrication industry, growing at a rate of about six per cent per year.
Automated welding technology, together with experienced welding professionals, are enhancing and increasing efficiency in the industrial fabrication industry for better outcomes as we know it.
The industry has moved from manual fabrication to comprehensive automation. The leap has been a large one, with massive reductions in labour and huge increases in output, and technology will continue to drive the industry forward.
This isn’t to say that every modern structural fabricator has become fully automated. The rate of technology adoption varies widely within the industry, and it has always been this way. Indeed, many may be surprised to find that some of the technologies described here have been around for so many years.
Some structural fabricators continue to move closer to full automation, while others remain manual in many respects. Regardless, automation technology is available, while skilled labour increasingly.