Low-Hydrogen Electrode Storage Condition

Date 11-23-2004 20:17

We have received our new copy of AWS D1.1:2004. I have been reviewed some sections to find changes. I read points 5.3.2.1 and 5.3.2.2 They made me get confused because they make a contradiction

Point 5.3.2.1 say "Immediately after openning the hermetically sealer container, low-hydrogen electrodes shall be stored in ovens helds at a temperature of at least 120 C. On the other hand the point 5.3.2.2 say "After hermetically sealed containers are opened, the electrode exposure to the atmosphere shall not exceed the values shown in column A. Table 5.1". We are employing E7018 so the max period of exposure are 4 Hours.
As you can see. the statement of point 5.3.2.2 is opposed to 5.3.2.1
so I don't know how interpret them. The client request me that we have to baked the electrodes after remove them of package and I tell him that we have 4 hours of allowable exposure time after package is open.
the code AWS D1.1 is mandatory in the project. We don't have electrode manufacter specifications.
I would like to know others points of view
Thanks.
Miguel

By thcqci

Date 11-29-2004 13:58

If you open a hermetically sealed cannister of E7018 rods, you do not need to bake them before use. You place them in your rod oven and then electrodes that are removed may not be exposed past times listed in D1.1. Whatever means works for tracking exposure time should be acceptable as long as it is effective. After excess exposure, then rods shall be re-baked or disposed of. We do not have a baking oven so exposure past time limits means trashing the rods (could get expensive if not controlled). We never leave rods out of the oven past dinner break or quitting time. Rods are placed in designated portion of the oven and the next morning may be re-issued. Rods removed from our oven are placed in rods holders (designed for that use) not cardboard boxes, buckets, sweaty back pockets, etc. Re-baking at the elevated temperature is mandatory as longer drying at around 250°F is not sufficient to remove possible moisture contamination. Also please note, rods may be re-baked only once, then if over exposure limits are exceeded, they must be disposed of. That is my opinion and I hope that helps.