Automated Welding: Pros and Cons

If you’re wondering how automated welding can enhance your value stream, here are the main pros and cons to consider.

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Automated welding can provide large gains in productivity and profitability – in the right applications. Welding is arguably the most complex manufacturing process and is frequently the least understood. A surprising number of companies spend millions of dollars to automate assembly while ignoring the welding process. Manual welding is still the best process for many assemblies. However, many assemblers are implementing automated welding systems to increase quality, productivity and profitability. Here we present the pros and cons of automated welding.

Semiautomatic and fully automatic
“Welding automation can be broken down into two basic categories i.e. semiautomatic and fully automatic. In semiautomatic welding, an operator manually loads the parts into the welding fixture. A weld controller then keeps the welding process, motion of the torch, and stillness of the parts to preset parameters. After the weld is completed, the operator removes the completed assembly and the process begins again,” says S M Bhat, Managing Director, Ador Welding Limited.

He explains, “In fully automatic welding, a custom machine, or series of machines, loads the workpiece, indexes the part or torch into position, accomplishes the weld, monitors the quality of the joint and unloads the finished product. Additional “part in place” and final product quality checks may also be designed into the machine if necessary. Depending on the operation, a machine operator may be necessary.”

Bhat believes that not every welding operation is a good candidate for automated welding. Applications will benefit most from automation if the quality or function of the weld is critical; if repetitive welds must be made on identical parts; or if the parts have accumulated significant value prior to welding. Excellent candidates for automation include batteries, capacitor cans, solenoids, sensors, transducers, metal bellows, relay enclosures, light bulb elements, fuel filters, thermos flasks, medical components, nuclear devices, pipe fittings, transformer cores, valve elements and airbag components. Companies that assemble limited quantities of products requiring accurate or critical welds may benefit from a semiautomatic system, but would probably not need fully automated systems.

Offers improved weld quality, increased output and decreased variable labour costs
Bhat informs “Automated welding systems offer four main advantages: improved weld quality, increased output, decreased scrap and decreased variable labour costs. Weld quality consists of two factors: weld integrity and repeatability. Automated welding systems ensure weld integrity through electronic weld process controllers. Combining mechanised torch and part motions with electronic recall of welding parameters results in a higher quality weld than can be accomplished manually. This offers instantaneous quality control. Furthermore, because a weld is made only once, defects are readily visible and detectable. Humans tend to “smooth over” a mistake with the torch, hiding lack of penetration or a possibly flawed weld. In some cases, leak testing and vision systems can be integrated into fully automated systems to provide additional quality control.”

Bhat suggests “Semiautomatic and fully automatic systems increase output by eliminating the human factor from the welding process. Production weld speeds are set at a percentage of maximum by the machine, not by an operator. With minimal setup time and higher weld speeds, a mechanised welding system can easily outpace a skilled manual welder.”

Require a higher initial investment than manual systems
Despite all the benefits, Bhat explains welding system automation is accompanied by some drawbacks. Although the drawbacks can be controlled, they should be recognised from the onset of an automated welding project.

Bhat says, “Automated welding systems require a higher initial investment than manual systems. A modern manual welding power supply costs less than $5,000; semiautomatic systems often start around $30,000. Companies considering fully automated welding systems should budget $175,000 to $250,000 for a turnkey system.”

He observes, “Flexibility is also an issue. The flexibility of a machine has an inverse relationship with the degree of automation. While a manual welder can easily move from one part to the next, specialised welding equipment and systems can only satisfy a dedicated niche in the manufacturing process. Flexibility of performance is exchanged for accurate, repeatable and precise welds.”
He also says, “When shifting from labour-intensive to capital-intensive processes, companies must adopt and rigorously follow preventive maintenance programs. Relying on one machine to do the work of eight welders is like placing all of one’s eggs into one basket. While the gains in productivity and profitability can be outstanding, an effective preventive maintenance program must be followed to minimize the risk of costly downtime. Depending on the complexity of the system, a maintenance program should include cleaning and lubricating the machine, calibrating
the controls and power supply, and replacing consumables.”

Bhat feels implementing an automated welding system requires a longer lead time for reaching full-scale production. If a company needs to begin welding parts immediately, manual machines may be purchased and implemented in a matter of days or hours. Semiautomatic machines can take 4 to 8 weeks to deliver. Fully automatic systems commonly have lead Arial of at least 20 weeks. The long-term benefits of automated welding systems often outweigh the initial costs of these lead Arial. As a result, delivery Arial should be considered in the planning process.

Bhat adds, “Before investing large sums in automation, assemblers should consider product life cycle. Most products follow a predictable pattern of introduction, growth, maturity and decline. Assemblers would be ill-advised to sink cash into automating the assembly of an eight-track tape player. On the other hand, the demand for airbag elements and automotive emission sensors will probably remain strong for years.”
ADOR Welding Limited offers standard and customised Automation solutions for different types of Industries:
Standard welding automation products:
• Column and boom
• Welding positioners
• Welding rotator
• Trolley for linear GMAW welding (MIG AUTOMATION)
• Trolley for circular shell welding (MIG)
• Fume extractor.

Application wise customised products:
• Square axle welding SPM
• Robotic welding
• H beam welding SPM
• Idler roller welding
• Cylinder welding SPM
• Weld Seamer.

Provides various benefits to users
Welding is considered the most complex joining operations involving numerous variable parameters including skills. “Automated welding provides main benefits to users like reproducible weld qualities irrespective of operator skills, increased output, reduces defects and scraps and decreases variable labour cost,” says Amlan Saha, Sales Project Management-Automation PW, Fronius India Pvt Ltd.

Saha adds, “Reproducibility of welding is most important for production lines producing numbers of components for automotive industries like two-wheeler and four-wheeler etc. Robotic and special purpose machines (SPM) are mostly employed for such applications. Part loading and unloading can also be mechanised with proper jigs and fixture assemblies along with mechanised welding systems. Consistency of quality is the prime requirement for such mechanised process. Assuming the system controller is functioning properly, whether the machine positions the parts or the torch within the specified tolerance for welding, solely depends on the quality of the system and intelligence of the system to understand the external environment correctly.”

Saha opines, “When the entire industry is moving towards Industry 4.0 or, cyber physical production systems, the most important for industry is to select the futuristic technologies which can handle large number of data for documenting, reporting and monitoring.” He further adds, “Apart from automotive industries the other industry sectors with high dependence on welding automation are critical manufacturing like defence, aerospace, rail transport, power, valves, oil and gas components, construction machinery and engineering fabrications. Human skill shortage across the industries and demands for higher production at lesser labour cost per component is creating a huge demand for mechanized welding systems.”

Major drawbacks of welding automation system
Despite all the benefits, welding automation system always has some drawbacks explains Saha like product life cycle vis-à-vis the initial investment for the welding automation systems, limitations of flexibility and hence requires a higher quality and consistency of input material.

Saha outlines, few points of Fronius Automated Welding solutions for Pipe welding, valves overlay, power and engineering sectors:

Fronius Welding Automation offerings to
industry:
• Customer-specific system solutions
As a systems supplier, we have been creating the most cost-effective, customer-specific and complete solutions for mechanised arc welding for over forty years.

• Overlay and joint welding
Whether they relate to the overlay or joint welding processes, the application areas are as challenging as they are varied and unique.

• Intelligent systems with leading welding technology
Our customers benefit from world-renowned Fronius welding technology, which optimises each and every one of our systems intelligently and efficiently.

• Significant competitive advantages for our customers
Equipped with many years of experience as the leading power source developer, we seamlessly incorporate our leading technology into mechanised systems to produce significant competitive advantages. Outstanding welding results, shortened welding cycles and a considerable reduction in costs guarantee maximum cost effectiveness.

Automate your Welding Process Today

Welding and Cutting Automation Plant and Equipment - New, Used and Refurbished for Sale

A Smarter Way to Welding Automation
As labour shortages continue worldwide, finding skilled welders is becoming a challenge for many businesses.
Welding automation offers a smart solution. Not only does it maintain high production quality and reduce defects, but it also brings long-term benefits that go beyond saving time and labour.

How to Get Started with Welding Automation?
The best approach is to start with simple tasks and gradually improve your production line. Avoid jumping into the most complex processes right away.
It's also important to note that automation can't fix issues from your suppliers, so improving upstream processes will ensure you get the most benefit from your automation investment. If you’re unsure where to begin, we have the experience and expertise to guide you. We’ll work with you to find the best solution that fits your production needs and budget.

Although there are many welding jobs which are best handled manually, and many more that can be done manually if necessary (as, for example, if a welding operation is too small to have an automatic welding machine, or if repairs must be carried out far from one of these devices), there are also many welds that can be handled quite adequately by an automated welding process. Some, such as pipe welding in the case of large pipes in many industrial applications (such as oil drilling platforms and chemical factories, to name only two examples), must be handled by an automatic welding machine such as an orbital welder, because of the precision that needed to avoid springing a potentially hazardous leak.

There are two different situations where an automatic welding machine is typically used. Semi-automatic welding uses a pre-programmed automatic welding machine, but the parts are actually loaded onto the welding bench (or its equivalent) by an operator, who arranges them and then switches on the welding machine until the weld has been completed. The operator then removes the finished workpiece and repeats the process as many times as necessary.

Fully automatic welding removes the human element except as an overall observer to make sure the machines are running properly. In these set-ups, the parts and finished workpieces are moved by other machines, such as conveyer belts, and the welding operation is often continuous over a large number of individual pieces. This is a truly industrial use of the automatic welding machine, and is found mostly in very large operations such as car factories.

Automatic welding machine benefits and drawbacks

Automatic welding machines have both their advantages and disadvantages, and as is the case with so many things, a gain in one place is compensated for by a loss in another. Automatic welding machines are much faster than skillful human welders can ever hope to be, and produce decent workmanship despite their greater speed. An automatic welder is roughly eight times faster than a manual welder. These welders do not pause or tire, although they may eventually become overheated and need to be shut down for a time. Since a lot of welding scrap is generated by welder fatigue when a human is wielding the electrode, there will be less wastage over the course of a long work day when automatic welding systems are the main ‘workers.’

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Automatic welding machines also provide a high quality weld, since they are totally uniform in their application of the electric arc or other welding tool. The machines are always on the job, unless they happen to break down, and once they have been purchased, they do not need to be paid.

Conversely, human welders still retain a few advantages over automatic welding machines. The cost of setting up even a modest array of automatic welders can be in area of a quarter million U.S. dollars, so the initial outlay on a human welder is much smaller. Automatic welders also take an extremely long time to set up, so the urgency of the welding job also needs to be weighed in the balance. Manual welding is extremely flexible, while automatic welding machines carry out the task in a repetitive manner and must be completely reconfigured if a different weld needs to be made. Also, if maintenance is not handled properly, the machines may break down and cause a disastrous pause in production. Automatic welding machines are fast, efficient, and highly useful, but they are not a complete solution to every situation and this must be borne in mind by their potential users.

Full or Semi Automatic welding systems come in many shapes and sizes and can be used for a variety of applications from welding pipe to ship building.

Column & Boom (TIG, Plasma, MIG & Submerged Arc Process)...

To meet the stringent requirements of aerospace and nuclear related applications column and boom manipulators need to provide exceptional rigidity and low deflection under load. Other important requirements include smoothness and consistency of axis movement. In meeting these demands a range of column and boom manipulators have been designed featuring high quality sub components and stress relieved fabrications that are incorporated into a design, which provides class-leading stability. This design philosophy is carried through to larger heavy-duty models.

Light duty and standard range generally have more applicability to Aerospace and light precision engineering applications, where minimal boom deflection and lack of vibration at full boom extension are important factors. Options exist for precision boom drive (for linear welding applications) or even precision column drive (vertical) utilizing recirculating ball screw type mechanisms. As for all column and boom manipulators both boom and column motions can be via precision bearings and guide ways. Design features include thick section fabrications that have been stress relieved to ensure highest standards of straightness and dimensional tolerance. Applicable weld processes include TIG, plasma welding and MIG/MAG, where high level weld head payload is not a primary factor.

Heavy Duty and Extra Heavy Duty column and boom manipulators share the same design features common to the light and standard duty manipulators so they also can be used for precision applications involving processes such as Dual Arc – Plasma / TIG. However, these units will find application mainly involving MIG/MAG and submerged arc (SAW) processes offer a range of optional extras including powered carts and king pin rotation of the column. Special oversized travel carts are available to carry all control and weld process equipment.

If factory space is an important consideration then we can offer models which feature telescoping of the boom, thus minimizing space requirements to the rear. Movement of the telescoping sections is synchronous to ensure the highest possible smoothness of motion is maintained.

All Column and boom manipulators are designed to work with a range of controls. Depending on size and duty, boom motion control may be via a frequency inverter type drive with encoder feedback.

Brands of Column and Boom welders include Bode, ESAB, SAF, Lincoln, Gullco, Pandjiris, Ransome, Arsonson

Seam Welders (TIG, Plasma & MIG Process)...

Longitudinal seam welding systems accommodate manufacture of tubes and pipes for a very wide range of material thickness and length. Applications range from the seam welding of small diameter tubes with short length and ultra thin wall thickness for bellows and instrument manufacture, through to large diameter beverage and brewing tanks, and thick wall pressure vessels. Brands of Seam welders include Bode, Jetline, ProArc, SAF, AMET, ESAB, Koike.

Get in touch with our team if you need assistance and advice on choosing the right machine and application for your project.

Seam Welding Industry Examples...

Below are some examples of advanced seam welding technologies being used in a variety of commercial sectors - Aerospace, Automatic, Bellows, Fume Extraction, Water Heating Tanks, Dairy machinery

Welding Lathes (TIG Plasma and MIG Process)...

Supplied are new and used Lathe type welders for circumferential welding systems to suit small components such as bellows, sensors and transducers, right through to a diverse range of larger components including, hot water tanks, fuel containers, nuclear waste containment, food and beverage containers.

For small to medium size components we offer our New Pro-Arc lathe range. These head and tailstock units feature ultra low backlash harmonic type gearboxes and encoder servo motor drive. Options exist for bench and freestanding models featuring controls suited to the most demanding precision application. Typical weld processes include Micro TIG, Micro plasma, TIG, Plasma and MIG.

Circumferential lathe type welding systems can accommodate components with diameters up to mm and weights up to 10,000Kgs. Smaller models are ideal for welding components such as Air Cylinders, Valve Assemblies, Catalytic Converters and Hydraulic Actuators. Various control options are possible including PLC, Typically welding process selection would be TIG, plasma and MIG reflecting thicker section weld requirements.  

Brands of lathe welding equipment include Bode, Jetline, Pandjiris, Pro-Arc, Weldlogic,

Welding Lathes Industry Examples...

Below are some examples of advanced welding lathe technologies being used in a variety of commercial sectors. Aerospace Technical Welding, Instrument and Transducers, Steam, Air and Water Pressure Welding, Welding of Munitions

Robotic Welding Equipment

There are two popular types of industrial welding robots. The two are articulating robots and rectilinear robots. Robotics control the movement of a rotating wrist in space. A description of some of these welding robots are described below: Rectilinear robots move in line in any of three axes (X, Y, Z). In addition to linear movement of the robot along axes there is a wrist attached to the robot to allow rotational movement. This creates a robotic working zone that is box shaped.

Articulating robots employ arms and rotating joints. These robots move like a human arm with a rotating wrist at the end. This creates an irregularly shaped robotic working zone. There are many factors that need to be considered when setting up a robotic welding facility. Robotic welding needs to be engineered differently than manual welding. A robotic welding system may perform more repeat ably than a manual welder because of the monotony of the task. However, robots may necessitate regular recalibration or reprogramming.

Robots should have the number of axes necessary to permit the proper range of motion. The robot arm should be able to approach the work from multiple angles. Robotic welding systems are able to operate continuously, provided appropriate maintenance procedures are adhered to. Continuous production line interruptions can be minimized with proper robotic system design. Planning for the following contingencies needs to be completed:
·Rapid substitution of the inoperable robots.
·Installing backup robots in the production line
·Redistributing the welding of broken robots to functioning robots close by 
Brands of Robotic welders include Motoman, OTC, Kuka, ABB, Fanuc, Panasonic, Miller, Lincoln

Benefits of robotic welding

Productivity

A robot typically works between two or more work stations. This means that during the robot welding cycle the operator is unloading a welded assembly and then loads new components to a welding fixture. Because there is less handling compared to a manual weld cycle the robot achieves much higher levels of arc-on time. The robot also moves very quickly between the joints and this yields a further saving in cycle time. Typically a robot system will increase output by a factor of two to four. This depends on the nature of welding. An assembly with lots of short welds can be produced with the most time savings. The cost savings that robot welding brings, can help companies to be more competitive and beat off competition from low cost manufacturing countries in Eastern Europe or China. In order to assess what sort of productivity improvements can be achieved it would be appropriate to compare manual welding times with robot welding times.

Quality

The robot has a very high repeatable accuracy (± 0.08 mm) and excellent path following accuracy. The robot presents the welding gun at the correct welding angle, welding speed and distance. The high level of integration to the welding equipment ensures that optimum welding conditions can be used for each and every joint. The end result is consistent high quality output, day in day out, year in year with reduced cost for rework, scrap or removal of weld splatter.

Consumable costs

It is up to the judgment of a manual welder to weld to the correct standard, but often the weld is oversize. A robot however, always welds to the correct length and size of weld that it has been programmed to produce. This means that some potential savings in wire consumption can be made. If for example a manual welder welds a 5 mm fillet, where only a 4 mm fillet is required, the savings in welding wire alone will be a staggering 36%!

Labour

In recent years it has become increasingly difficult to employ manual welders. There tends to be a certain amount of staff turnover and this of course carries a cost for recruitment and training. When labour is an issue companies often find themselves working overtime or having to employ additional contract labour to meet demands and this can have a serious impact on production costs. If products cannot be supplied to the end customer, penalties may be incurred or future business may be at risk. Whilst there will always be a requirement for manual welding, companies that invest in robotic automation are much less dependent on manual welding.

Safety

A robot welding system addresses health and safety issues associated with dangerous welding fumes and exposure to arc-flash. Companies can reduce the risk of their employees claiming compensation if they are affected by the hazardous working environment.

Flexibility

The robot can be used to weld many different products and allows companies to consider Just In Time production. By reducing work in progress and stock levels, savings can be made due to fact that less value is added to stock levels in terms of labour, transport and storage costs.

Floor space

Compared to the same output from manual welding bays the robot requires less floor space.

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