Frequently Asked Questions

SMAW (Shielded Metal Arc Welding) is a manual arc welding process that is often called stick welding. It is one of the most popular welding processes used today. Its popularity is due to the versatility of the process and the simplicity and low cost of the equipment and operation. SMAW is commonly used with such materials as mild steel, cast iron, and stainless steel. The process requires a consumable electrode that is coated in flux (stick rod) to lay the weld, and an electric current is used to create an electric arc between the electrode and the metals that are being welded together. The electric current may be either an alternating current or a direct current from a welding power supply. While the weld is being laid, the electrode’s flux coating disintegrates. This produces vapors that provide a shielding gas and a layer of slag. Both the gas and slag protect the weld pool from atmospheric contamination. The flux also serves to add scavengers, deoxidizers, and alloying elements to the weld metal.

In stick welding (SMAW), the most commonly used welding electrode is low hydrogen 7018. It is covered with flux which is hygroscopic (easily absorbs moisture from the air). This flux coating burns and converts into a shielding gas that protects the weld pool from atmospheric contaminants such as hydrogen, nitrogen, oxygen and others. If these contaminants enter the weld pool they will cause defects such as cracking, and porosity (worm holes.) These defects can create a weak point at which the weld may fail under stress or load.

Low-hydrogen 7018 rods are just what their name states…low hydrogen. They allow very little hydrogen into the weld pool unless they have been stored improperly and contaminated by moisture. Moisture allows hydrogen into the flux, which is then introduced into the weld pool adversely. This moisture contamination is super-heated during the welding process, converts into steam and then bubbles up to the surface leaving an open pocket in the finished weld bead. So at that particular spot the weld is weaker because it is not a solid bead. This will happen at the beginning of the bead with each new rod used, and diminish as the rod heats up and burns the moisture out as it is being consumed.

Moisture-contaminated rods may make a good-looking weld at first, but they will be subject to longitudinal cracking either right after welding, or later on (longitudinal cracking occurs where a crack begins at one point and follows the length of the weld). Defects may also be noticed by a visiting welding inspector as described by one of our seasoned welders here:

Don't Make the Welding Inspection Mad!

Many welding job sites and shops do not follow proper electrode storage guidelines set forth by welding electrode manufacturers and the American Welding Society.

For specific storage and rebake temperature guidelines, we recommend contacting the welding consumable manufacturer directly. It is also important to check with local welding codes and/or ask a welding inspector to provide some information. Welding standards change frequently, and each manufacturer often provides a different recommendation regarding welding electrode storage. Check the packaging and also manufacturer websites for information. Keen offers a wide range of products to handle almost any welding consumable storage requirement.

Generally, there are two processes involved with the proper maintenance of stick welding electrodes: holding (also called storing) and rebaking (also called reconditioning).

The holding process refers to the short-term* or long-term** heated storage of welding electrodes to maintain factory-fresh dryness. Storing the rods at elevated temperatures prevents atmospheric moisture contamination of the electrode’s hygroscopic flux coating. There are various temperature requirements according to the type of electrode and also that are also set forth by welding codes. For specific holding temperature guidelines, please contact the manufacturer of your consumable.

The rebaking process refers to the short-term*, high-temperature heating of welding rods that have been or may have been contaminated by atmospheric moisture. The rebaking process “reconditions” the welding rod, meaning it bakes out the moisture that has entered the coating thus restoring the electrode so it is suitable for reuse.  Many large shops have a rebake rod oven in the tool crib in which electrodes coming back from the field are procedurally rebaked as a precaution to remove any moisture, and then put into a holding oven for long-term low-temperature storage for reuse. For specific rebake temperature guidelines, please contact the manufacturer of your consumable.

* - In relation to our products, we consider short-term to mean 8 hours or less.

** - In relation to our products, we consider long-term to mean 24 hours/day 7 days/week.

Keen rod ovens are specifically designed according to the temperature range of the process, and the amount of electrodes to be stored. The standard holding ovens are designed to accommodate a maximum temperature of 550F and the rebake ovens are designed to reach 999F. The higher-temperature ovens have larger wall thicknesses to accommodate more insulation, explosion proof latches and digital programmable temperature controllers. The large, floor-positioned holding ovens feature basic digital temperature control, and the bench and portable ovens have analog temperature control or constant input without thermostatic control.

Portable welding electrode ovens are designed primarily for short-term holding, not long-term holding. Portable units are commonly used by individual welders in the field to keep electrodes dry at the welding station. Typically, welders are provided electrodes that are stored in a larger, long-term holding oven at the tool crib. They load up their portable for a day’s work, and any that are left at the end of the day are returned to the crib for rebaking or long term storage. The portable is shut off until the next time it is used in the field.

Yes. Keen holding ovens from 200 lbs capacity and up are designed to be run 24 hours/day, 7 days/week. The idea is to keep all unpackaged electrodes at elevated temperatures all the time to preserve the integrity of the electrode and to ensure optimal welds.

Use this formula: Watts / Voltage = Amps

The AWS specification for carbon steel electrodes (AWS A5.1), E70XX maximum limit is 4 hours.

For the AWS 5.5 specification, please see below:

One welding rod storage myth perpetuated by some in the industry is that an old refrigerator equipped with a light bulb will sufficiently heat the covering on low-hydrogen electrodes to the consumable manufacturer recommended storage temperature range of 225-300F. Most light bulbs do not provide sufficient heat to bring the electrodes up to the proper temperature to stave off moisture contamination in the covering.

Another myth that we have come across over the years is that storing welding electrodes in a freezer will keep the rods dry. This of course is a myth because as soon as the rods are removed from the freezer they will be a magnet for any atmospheric moisture that exists in the air and produce condensation on the coating.

It is always best to review instructions on the manufacturer’s packaging, and to consult the manufacturer for guidelines of if you have any questions pertaining to proper storage.  Please note that not everyone is informed about welding rod storage, even in customer service departments at major manufacturers. It is best to speak with an experienced welder or inspector that knows AWS SMAW specifications and proper industry-approved storage guidelines.

Welding electrodes are manufactured to be within acceptable moisture limits consistent with the type of covering and strength of the weld metal to be used with the electrode. They are then packaged in a container which has been designed to provide the degree of moisture protection considered necessary by the industry for the type of covering involved.

Some common handling mistakes of welding rods are:

• Exposing to atmospheric moisture beyond the consumable manufacturer’s suggested time limits
• Storing rods in opened factory packaging
• Opening the container from the wrong end
• Tossing the rods around which can crack the low hydrogen coating on the welding rods thus rendering them useless
• Exposing to abrupt temperature fluctuations, particularly from cold to warm areas – condensation may be drawn to the coating
• Exposure to grease or dirt which also contains moisture

Poor arc direction, excess spatter, poor shielding, lack of penetration and porosity are common results that occur when welding rod coatings have been contaminated by moisture.  Another common occurrence is “fingernailing” which is a term used to describe uneven burn-off on one side of the welding rod. This is often due to moisture contamination in one area of the electrode causing it to burn off more slowly than other areas.

Porosity: formed by entrapment of discrete pockets of gas in the solidifying weld pool. The gas can be formed in a variety of ways: poor gas shielding, surface contaminants such as moisture, grease, rust. Porosity can also result from insufficient deoxidants in the parent metal, electrode of filler wire.

Wormholes: A severe form of porosity caused by heavy contamination of the weld pool as a result of surface contamination or welding with damp electrodes. Under radiograph, they appear as elongated pores and are indicative or a large amount of gas that has formed in the weld which is trapped by the solidifying weld metal.

Hydrogen: Contributes to cracking in the solidified weld. In combination with high tensile stresses and sensitive steels, hydrogen can cause cold cracking several hours or days after the weld is complete. For structural welding using high strength steels, consumables that give low hydrogen levels are often used. These types of consumables are prone to moisture pick-up and must be stored at elevated temperatures.

Visually inspect the rod coating to determine if the color has changed during storage. Any discolored welding rods should be discarded or your supplier should be contacted. Also visually inspect for physical damage to the coating that may have occurred during handling. Any sections of the rod coating that may have been damaged will render the rod useless and it should therefore be discarded.

Check the consumable packaging for information, your local supplier and/or the manufacturer of the consumable you purchased. Please note that not everyone is informed about proper welding rod storage, even in customer service departments at major manufacturers. It is best to speak with an experienced welder or inspector that knows AWS SMAW specifications and proper industry-approved storage guidelines.

Proper storage procedures should be followed for all types of welding electrodes. Please consult the consumable manufacturer for specific instructions. It is generally accepted that the same storing and rebaking procedures for low-hydrogen welding rods also apply to stainless steel welding rods. Cellulosic electrodes should not be stored in an oven because moisture exposure does not have a detrimental effect on performance. If non-low-hydrogen rods have been exposed to moisture, they can be heated in a rod oven at low temperatures only (100-120°F).

This can present some problems, and the consumable manufacturer must always be contacted before storing multiple types of electrodes together in a single rod oven. Welding electrodes are manufactured to have a specific range of moisture content. For example, low-hydrogen rods have a moisture content of approximately 0.1 – 0.4 percent. Cellulosic rods on the other hand have a moisture content of 4 to 6 percent. If these two types of electrodes are stored in the same oven, the lower moisture content low-hydrogen rods will absorb moisture from the higher moisture content cellulosic rods. It is important to note that cellulosic rods are not to be stored long term in a rod oven, and are only heated at low temperatures (100-120°F) if they have been exposed to humid air for an extended period of time.

We manufacture all of our TIG filler wire storage ovens, TIG filler rod cabinets and all other products in the USA. Our facility is located in Hammond, Louisiana and we have been producing products for the worldwide welding industry since 1923. Although it has undergone several expansions, we still operate in the same facility as we did almost one hundred years ago. Our team has always been and remains dedicated to the welding industry – one of the great industrial trades.

For those companies that seek to establish procedures for filler material preparation before welding and to implement good practices to avoid contaminants that cause adverse effects in the final weld, Keen TIG filler wire storage ovens and cabinets provide an ideal solution in a variety of ways. Using our TIG filler rod storage ovens provides continuous, heated storage at low temperatures which is an ideal environment for TIG filler rods and wire because the problem of humidity is eliminated. Many customers store their TIG straight length and cut to length filler wire in the factory packaging  inside the oven, and even at 150F the humidity level is negligible. The key is evenly distributed heat across the entirety of all TIG filler wire being stored, an impossibility using less effective heating methods such as cabinet with a light bulb. Maintaining cleanliness of filler materials and by providing your clients proof of compliance with specific welding codes demonstrates that your filler material preparation control procedures are thorough and professional. 

We have been developing innovative welding consumable storage products in the USA for almost 100 years. Over the decades, as many industries flourished and the welding industry in general experienced changes and growth, Keen has been there providing solutions for all types of welding professionals seeking to enhance and improve their processes. The variety and depth of our product line represents the evolution the welding industry has experienced over the decades, and exemplifies our dedication to the welding industry as a whole. Customers choose Keen because we have a solution for almost any requirement when it comes to welding consumable storage.

Our process begins with the customer. We utilize the latest in 3D CAD/CAM technology to produce our designs. Many of our products have been custom designed for a specific customer’s need, only to later become a standard product that is sought out by other customers with similar requirements. Our ability to customize has driven our product line growth as we catered to the unique needs of industries and customers. Implementing the latest in ERP software has streamlined our processes, and we produce our assemblies from American-made steel through all fabrication processes including punching, forming, welding, assembly, powder coating and baking testing and so on. Everything we produce is made in the USA at our facility in Hammond, LA.

Control of  GTAW TIG filler material is an essential part of the entire welding process and is often overlooked. Atmospheric moisture and hydrocarbons found in lubricants can contaminate TIG filler material and enter the final weld causing worm holes and porosity. It is important to establish procedures for proper storage and control of TIG filler rods to prevent adverse effects; avoiding moisture, dust, oils, handling with unclean hands, dirty boxes, etc. is critical to prevent corrosion in filler materials. Proper TIG filler wire storage can also reduce pre-weld preparation time and improve efficiency downstream.

Our TIG filler wire storage products category comprises a wide variety of capacities which demonstrates the unique needs of GTAW welding professionals. From the portable KT-50-36 to the forced-convection KT-20FC-36, Keen TIG GTAW TIG filler rod storage ovens can be very different and are suited to specialized requirements. Our standard KT-99 available in 3 shelving configurations is very popular with the growing aerospace and aviation market, two industries in which both weld quality and proper TIG filler rod storage are crucial. We offer several small capacity models like the KT-4-36 and K-360-36 which are dependable bench top models, and the KT-54NH and KT-30NH are heavy-duty unheated storage cabinets for simple organizational needs and to keep dust and over handling away from the TIG filler wire. The TIG filler wire storage cabinets are also lockable.

For the ultimate in contaminant-free storage, customers involved with critical welds sometimes choose the inert gas purge models like the kT-99NP and K-1000M&TNP. Nitrogen and argon are the standard mediums for contamination-free storage because these gases are relatively inert – they neither react with stored materials nor carry moisture - and because they can be isolated and purified relatively inexpensively. Because argon and nitrogen have a lower-specific gravity than air, when introduced into the oven they immediately purge air that may contain contaminants or moisture. Keen inert gas purge welding ovens are often used for highly sensitive applications in the nuclear marine and aerospace industries.