Welding Productivity: Arc Time, Deposition and Rework

Improving welding productivity starts with understanding where the time goes across the whole job. Fitting parts, changing consumables, cleaning welds and waiting for materials can all matter as much as welding speed. Looking at these activities together helps you see which are essential and where better planning, equipment or maintenance could reduce avoidable delays.

This guide will help you identify those delays and consider which equipment and consumables could make a useful difference, so you can finish sound welds more efficiently.

Where Welding Time Goes

A useful starting point is to measure arc-on time: the time spent actually welding, with the arc burning. Expressing this as a percentage of the period measured gives the operating factor. When looking at published figures, bear in mind that they may exclude setup and assembly, so they cannot always be compared with a full shift. For your own jobs, include fitting, cleaning, inspection and waiting so you can distinguish avoidable delays from the preparation and checks the work needs.

How Welding Process Affects Output

When comparing welding processes, you will also come across deposition rate, which measures how much weld metal is added per hour while the arc is on. It leaves out electrode changes, cleaning and setup, so it describes only part of the job. The consumable, diameter, current and welding position all affect the rate, making it important to compare product data at settings you can actually use.

Process	How it can help productivity	What to allow for
General-purpose stick electrodes, such as E6013	Useful for general fabrication and repairs, with output depending on electrode size and current	Unused electrode ends, frequent electrode changes and slag removal between weld passes
Iron-powder stick electrodes, such as E7024	Can add weld metal faster than general-purpose electrodes on suitable joints	E7024 is limited to flat welds and horizontal fillet welds, so the job must permit both the position and the electrode type
MIG and MAG solid wire	Continuous wire feed reduces stops and leaves no flux slag to chip off	Needs suitable shielding gas, protection from wind and properly cleaned material
Flux-cored wire	Can achieve high deposition rates, with suitable all-position wires helping on vertical and overhead welds	Allow for slag removal and follow the wire’s permitted positions and shielding requirements. Some wires need gas while others are self-shielded; the joint still needs cleaning as specified

Each electrode change in stick welding leaves an unused end, known as a stub. As an example, a 50 mm stub from a 350 mm electrode represents about 14% of its length, although actual stub lengths vary. That percentage describes unused length rather than total consumable cost or total material loss. Measuring both the stubs and the changeover time on your own jobs gives you a clearer picture of what happens in practice.

For larger welds in flat or horizontal fillet positions, E7024 can be a useful choice because the iron powder in its coating adds metal to the weld. The time saved will depend on the products and settings, however, so there is no fixed speed advantage over E6013. Compare the products at settings that suit the work and confirm that the welding procedure permits the change.

For work that suits solid-wire MIG, moving from stick welding can save the time spent on repeated electrode changes and flux-slag removal. To judge the benefit for your job, look at gas shielding, access, setup and the required weld quality as part of the comparison.

If you need several welding processes, a multi-process machine can bring them together in one unit. The available functions vary between models, so look at the processes, TIG functions and accessories included. Some machines do not provide AC TIG or come with everything needed to use the processes they support.

Duty Cycle and Cooling Time

Duty cycle helps you judge whether a machine can sustain the workload you have in mind. It states how long the machine can weld at a specified output within a test period, usually ten minutes. For example, a 200 A rating at 30% duty cycle allows three minutes of welding and seven minutes of cooling within that period, under the stated conditions. Treat this as a working limit rather than a prediction of exactly when the machine will trip.

If overheating repeatedly stops production, first establish whether the machine is being asked to exceed its rated workload, has restricted airflow or needs maintenance. Once you know it is working properly, you can assess whether its duty rating is sufficient. A higher rating may reduce cooling delays where the existing machine cannot sustain the job.

• Check the rating at your welding current. The useful figure is the one at the output your job needs, because a high duty cycle at a low current does not tell you how long the machine can run at a higher output.
• Check the test temperature. The rating applies under stated conditions, and cooling performance can fall if the surrounding air is hotter than the rated temperature.
• Keep cooling airflow clear. Blocked vents or restricted airflow can cause overheating, so follow the manufacturer’s clearance and cleaning instructions.

For help considering these specifications together, our guide to choosing a welding machine explains how amperage, duty cycle and power supply fit together.

Reducing Consumable Changes and Delays

Wire, electrode and gas changes are a normal part of welding, but good stock control, storage and maintenance can make those planned changes quicker and reduce unnecessary stops between them.

Cause of delays	What to improve
Running out of consumables during a job	Base minimum stock levels on how much you use and how long deliveries take, keeping enough for normal work within the amount you can store and use properly.
Frequent wire-spool changes	Larger spools may help if they fit the feeder and you will use the wire before storage conditions affect it. Include handling, change time and price in the comparison.
Opened low hydrogen electrodes absorbing moisture	Ovens and quivers help keep dry electrodes ready for use when you follow the product’s storage temperature and exposure limits. A heated holder does not automatically restore electrodes that are already damp.
Wire jams, tangled wire at the feeder or an unstable arc	Work through the liner, contact tip, drive rolls, spool brake and feed pressure. The parts need to be sized for the wire, with worn or damaged items replaced.
Searching for the right consumable	Label storage with the full classification and size so products are easy to identify. Keep product, batch and approval details available to check against the welding procedure before making a substitution.

If you are reviewing how you choose and store electrodes, our electrode selection guide and ovens and quivers guide explain what to look for.

Reducing Weld Repairs

The work involved in a weld repair goes beyond welding the joint again. You first need to find the defect and remove the affected metal, then recheck the result after welding. Although the cost varies with the defect and the job, preventing repeated faults avoids all of this extra work.

It helps to record repair time separately from general welding time, so you can see how much it costs and whether the changes you make are reducing it.

• Look for recurring causes. Work through the settings, joint preparation, consumables, equipment and technique, allowing for the possibility that more than one factor is causing the defect. Our guides to TIG defects and MMA problems explain the common problems and help you decide what to check.
• Keep low hydrogen electrodes dry. Following the storage rules and welding procedure helps address the risk from moisture, which can contribute to hydrogen cracking hours after welding.
• Find out what the grinding is for. High grinding disc use can be a sign of weld repairs or excess weld metal, although necessary preparation and specified finishing also use discs. Look at the work being done before deciding how much of that grinding could be avoided.

Setting Up and Positioning the Work

Fit-up and joint setup deserve attention because they can account for a large share of the job. Getting the parts aligned accurately and making the joint easier to reach can reduce repeated adjustments and the need to weld in awkward positions.

• Position the joint for easier welding. Where the procedure allows it, flat welds or horizontal fillets can make the molten metal easier to control and allow higher deposition rates. The benefit needs to be weighed against the time, effort and cost of turning the work. Our welding positions guide explains the differences between positions.
• Support and clamp the parts securely. Keeping the setup stable helps the joint stay aligned and reduces the need for repeated adjustments. Pipe stands and clamps can help with this, and our guide to pipe clamps for welding and fabrication explains the different types.
• Support heavy tools. A tool balancer can carry much of a heavy gun’s weight, helping the operator position it steadily while reducing fatigue.
• Protect nearby workers from arc light. Suitable welding screens help separate welding from nearby work, alongside the fume controls and welder’s protective equipment that are still needed.

Maintaining Fume Extraction

Fume extraction is normally an important part of controlling exposure during regular indoor arc welding. In UK workplaces, welding fume must be adequately controlled following a risk assessment, using suitable local exhaust ventilation (LEV) where practicable and respiratory protection where needed. The controls need to suit the work, as extraction alone may not provide enough protection.

• Check extraction before starting. Follow the manufacturer’s instructions for checking airflow indicators and filter condition, cleaning or replacing filters when required. Planning the servicing helps reduce unexpected stops.
• On-torch extraction can reduce hood adjustments. Because the extraction moves with the torch, it can help on suitable MIG/MAG work, provided it captures the fume effectively in the positions you use.

For help with sizing and setup, see our guide to choosing and maintaining fume extractors. The COSHH and LEV guide explains the compliance duties that go with using the equipment.

Where to Start

1. Measure representative jobs. Include welding, setup, handling, cleaning, inspection, repairs and waiting in your records, repeating the check across enough jobs to see the usual pattern.
2. Record weld repairs separately. Tracking both the time spent and the causes for a month will help you identify the problems that keep returning.
3. Investigate machine cut-outs. Start with the duty rating, cooling airflow and any fault indications, so you can understand the cause before deciding whether a larger machine is needed.
4. Record why welding stops and for how long. This helps separate necessary tasks from avoidable delays and shows whether a few long waits are costing more time than many short stops.
5. Fix confirmed, low-cost problems. A damaged liner, a poor work return connection or unsuitable electrode storage may be all that needs attention, so let the evidence guide what you buy.
6. Compare larger changes using your measurements. When looking at different processes or machines, include equipment, training, setup, running costs and weld quality in the comparison, then trial the change on suitable work before committing.

Frequently Asked Questions

If you are dealing with a recurring delay and would like help, use the technical enquiry form to tell us the welding process, material and what is holding up the work. We can help you assess whether a simple repair, a different consumable or a change of equipment is likely to make a difference.