STORAGE, HANDLING & SHELF LIFE OF SMAW/MMAW ELECTRODES
Stick-electrodes are primarily designed & developed to obtain the most vital chemical, mechanical & metallurgical necessities of the weldments with their requisite operating behavior. They are manufactured to be within the acceptable limits of chemically combined water, consistent with the style of flux covering & Weld strength; key factors in exceptional performance of electrodes. However, prolonged storage in a highly humid atmosphere and undue increase in hygroscopic properties, impairs the original feature of stick electrodes. Thus, it is best recommended to store the electrodes free from moisture, in a safe environment & discharge them onfirst in & first out rule basis.
In certain cases, it may be reasonable to re-dry the coated electrodes, even though it may not be recommended by the manufacturer. If the flux covering exhibits an excessively high level of absorbed moisture as a result of an inappropriate state of storage or any other adverse influence (which is normally reflected while welding by the increased formation of sticky or sluggish slag covering, unsteady arc, cracking, cavity, porosity, worm holes, spattering etc.), then the electrodes needs to be dried at 80 to 110 0C for an hour before use.
Recommended Re-drying: *
Electrode's Flux Type
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AWS Class
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Drying Temp, & Time
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Holding Oven Temperature
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Cellulosic
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EXX10, EXX11 EXX10-X, EXX11X
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N. R.
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N. A.
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Rutile & Rutile - Cellulosic
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EXX12, EXX13, EXX14, EXX24
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100 to 1100C for 1hr.
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N. R.
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Acidic.
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EXX20, EXX22
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150 to 1800C for 1hr.
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--- ,, ---
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Basic - hydrogen controlled to arrive at the moisture content level 0.6% max.
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EXX15, EXX16
EXX18
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230 to 2600C for 2hrs.
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100 to 1500C
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Basic - hydrogen controlled to arrive at the moisture content level 0.4% max.
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EXX15, EXX16
EXX18, EXX18-1
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370 to 4000C for 1-hr. or
300 to 3500C for 2-hrs.
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--- ,, ---
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Basic - hydrogen controlled to arrive at the moisture content level 0.2% max.
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EXX15, EXX16-X
EXX18-X, EXXX18-X
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400 to 4500C for 1-hr.
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--- ,, ---
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Stainless steels - [Rutile]
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EXXX-16, EXXX-26
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3000C for 1-hr.
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--- ,, ---
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Stainless steels - [Rutile-Acid]
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EXXX-17, EXXX-27
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3000C for 2-hrs.
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--- ,, ---
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Stainless steels - [Basic]
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EXX-15, EXX-25
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3000C for 2-hrs.
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--- ,, ---
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[Note: *
AWL's Vacuum packed R2U (Ready To Use) electrodes are neither re-dried or baked, & are made to use straight from the electrode packet without the need of cumbrous & costly re-drying or baking procedures (within a stipulated period of up to eight hours after opening the electrode's covering) either on shop or site.]
The original cardboard boxes/containers should be kept intact thereby avoiding any physical damage while in transit/handling.
Electrodes should be in a storage room protected from direct air drafts entering through doors, ventilators or windows. Additionally they should also be kept away from contact to any walls or floor, preferably on the steel racks (not over the moisture absorbent wooden racks).
Electrode's should be kept in a cabinet or store room at 10 to 150C above the ambient temperature at (Relative Humidity) R.H. less than/equal to 60% for the room temperature of 20+20C or R.H. less than/equal to 50% at 30+50C.
ATTRIBUTES OF ADOR WELDING's R2U ELECTRODES:
1- Convenient, puncture proof, 2-Kg R2U electrodes packed safely under the multiple layer of plastic & aluminum foil.
2- R2U electrodes packets eliminate the added burden of storage, handling, re-drying or baking.
3- Original low hydrogen attribute is retained securely upto 8-hrs after opening the packet.
4- Consistent weld quality is preserved (even under the hostile weather conditions) on shop or site.
5- Reduces the risk of Hydrogen embrittlement, delayed under-bead or cold cracking.
6- Saves time and thus improve productivity.
7- Saves the cost of energy as re-drying is not required & purchase of an electrode-drying oven.
8- Shelf life of R2U electrodes will be atleast five-years. Whereas the ordinary cardboard type packaging is considered to be safe for a period of only six to twelve months.
CONCLUSION:
Experience has shown that the electrodes are a delicate commodity and thus need to be stored and handled with great care to ensure a prolonged shelf life and performance. Irrespective of the manufacturing date, non-conformities such as eccentric coating (manufacturing deficiency) electrodes, non-identifiable electrode, excessively damp or wet electrodes, soiled with hydrocarbons (oil, grease etc.), rusted iron powder or the core wire, bent or cracked electrodes, or fragile flux covering (caused by the protracted poor storage circumstances) make stick-electrodes impractical; or other wise as long as electrodes are free from the above described deficiencies and meet the demand of your welding specifications can very well be utilized merely by carrying out a performance qualification test. The care in storage & handling by the end user will be the key factor in guaranteeing the shelf life of flux coated stick-electrodes.
For further details Please contact us at .......
cmo@adorians.com
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ADORPORT/ ADORDRY-III/ III/ ADORFLUX
Reliable ovens which work consistently.
User friendly.
Portable ovens for small volumes & mother ovens with bulk holding capacity.
Special custom build available as per customers applications.
Temperature Control :Provided with thermostat control for precise setting of drying temperature required for various types of electrodes.
Flawless Welds : Totally dry welding consumables yield radiographic quality welds.
Robust construction.
Heavy duty metallic body.
Uniform heating of charged materials.
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