Our recommendations regarding shelf life are based on two facts:
1. We havet an internal shelf life limit of 5 years, because the products may become obsolete. There may have been changes in material requirements and / or welding performance during the years.
2. Deterioration due to the effect of moisture:
Electrodes packed in hermetically sealed packages, like Esab´s vacuum pack, are not effected and can be stored more or less for ever, provided the vacuum is not lost. Other types of packages gives much less protection. If electrodes, or flux, are stored in a dry environment, that is air with relative humidity around 40% or less, very little deterioration takes place. In high humidity atmosphere moisture pick-up and deterioration is rather rapid. Rebaking of stainless and mild steel basic and low hydrogen electrodes and flux will restore their properties.
Flux in big-bags and electrodes on fully loaded pallets will not be affected by moisture as rapidly as flux in smaller containers or electrodes in loose packades. The moisture has to be transported from the atmosphere into the material, and this is a rather slow process.
All together the 3 year rule is a good rule and material more than 5 years old has to be stored under dry condtions if to be used. Mechanical properties and chemical composition of the weld metal are not affected by storage time.
Best regards,
Claes Gillenius
Development Engineer, MMA. (Spec. stainless and non Fe-alloys)
Direct tel: +46 (0)31 509315
Mobile +46 (0)707532012
Company ESAB AB
Address Box 8004, 402 77 Gothenburg, Sweden
Lindholmsallén 9
Company reg number 556005-7738
| "pgoswami" <pgoswami@quickclic.net> Sent by: materials-welding@googlegroups.com 2010-02-04 07:17
|
|
Hi Louis & Yanferizal,
Thanks for your query and answers.
Discussion thread, (MW-3238, Sept-2009) Shelf life of Low hydrogen electrodes provides some snapshots of intense discussion on the above topic.
It's true that boiler or pressure vessel codes or structural welding codes do not specify the shelf-life or expiry dates of welding electrodes. For example, ASME Nuclear Codes Sec-III, Clause & NB, NC-2440 specifies that:- Suitable storage and handling of electrodes, flux, and other welding materials shall be maintained. Precautions shall be taken to minimize absorption of moisture by fluxes and cored, fabricated, and coated electrodes.
The shelf-life of welding electrodes to a great extent depends on electrode manufacturer's methods, quality control procedure and how electrodes are handled. Depending on the coating type, packing (hermetically sealed or not), storing methods and ambient conditions, humidity etc, electrodes may last long or less. However as a good practice and based on electrode manufacturer's guidelines it may be worth considering:-
· Solid Wires, GTAW/GMAW-No shelf Life.
· Cored Wire –FCAW- No shelf life
· SMAW – The rule should be FIFO (First in First Out). Electrodes where the coating shows sign of flaking, cracks etc certainly should be discarded without much thoughts. Electrodes not older than 2-3 years but in good condition may be used. If required the diffusible hydrogen test could be repeated. Electrodes older than 3 years generally should not be used as a good engineering rule.
· SAW Fluxes- Shelf life 2-3 years maximum subject to the flux condition and amount of fine particles/dust generated and behavior during welding
It would be definitely useful to get the inputs from other forum members, especially from consumable manufacturing industries.
Thanks.
Pradip Goswami, P.Eng
88,Garth Trails Crescent
Hamilton,Ontario, L9B2X1,Canada
Email-pgoswami@sympatico.ca
Email-pgoswami@quickclic.net
Tel-905-679-9677
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of A D
Sent: Wednesday, February 03, 2010 12:39 AM
To: materials-welding@googlegroups.com
Subject: Re: [MW:4192] Welding Electrode Expire Date
| Hi, Electrode (SMAW) expiry detail is not given by any codes. May be you can check with your electrode manufacturer. wire consumables (without flux) is not issue for expiry, we can use anytime if we keep in proper storage. In stick electrodes, flux may be loosened (unbounded) due to long storage. Louis --- On Wed, 3/2/10, yferizal@gmail.com <yferizal@gmail.com> wrote: From: yferizal@gmail.com <yferizal@gmail.com> Subject: [MW:4187] Welding Electrode Expire Date To: materials-welding@googlegroups.com Date: Wednesday, 3 February, 2010, 8:13 AM Dear All, Anyone could inform me the welding electrode expiration date since manufacture (eel 1 year, 2 year etc) it is not mentioned in the electrode certificate. Is there any statement in Code/standard for this? Best Regards, Yanferizal Powered by Telkomsel BlackBerry® -- To post to this group, send email to materials-welding@googlegroups.com To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com For more options, visit this group's bolg at http://materials-welding.blogspot.com/ The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents. |
Your Mail works best with the New Yahoo Optimized IE8. Get it NOW!.
--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
This communication and any files transmitted with it contain information which is confidential and which may also be privileged. It is for the exclusive use of the intended recipient(s). If you are not the intended recipient(s), please note that any disclosure, copying, printing or use whatsoever of this communication or the information contained in it is strictly prohibited. If you have received this communication in error, please notify us by e-mail or by telephone as above and then delete the e-mail together with any copies of it. ESAB does not accept liability for the integrity of this message or for any changes, which may occur in transmission due to network, machine or software failure or manufacture or operator error. Although this communication and any files transmitted with it are believed to be free of any virus or any other defect which might affect any computer or IT system into which they are received and opened, it is the responsibility of the recipient to ensure that they are virus free and no responsibility will be accepted by ESAB for any loss or damage arising in any way from receipt or use thereof.
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding-unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
No comments:
Post a Comment