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Storage and handling of submerged arc wel-
ding fluxes
Elgaflux and Cromaflux fluxes are supplied as stan-
dard in 25kg moisture resistant plastic bags, 25kg
hermetically sealed aluminium-coated plastic bags,
25kg plastic lined moisture resistant paper bags and
600kg coated fabric BigPac bags. All fluxes have a
guaranteed low as-manufactured moisture content
that can be maintained by observing the following
recommendations for storage and handling.
Transport
Flux is normally supplied on plastic shrink wrap-
ped pallets with a net weight of 1000kg or 1200kg.
BigPac bags are supplied individually on shrink
wrapped pallets. Transportation should be carried
out in covered vehicles and direct exposure to rain
and snow avoided.
Main storage
Agglomerated and fused fluxes should be stored in
their original, undamaged packaging under properly
maintained climatic conditions as follows :
•Temperature 15-35
o
C
•Relative humidity As low as possible,
maximum 70%
Stored under these conditions the lifetime for agglo-
merated fluxes is 3 years and that for fused fluxes 5
years. Stock control should encompass the first-in,
first-out principle.
Storage and handling in the workshop
When handled and stored according to conditions
described above, flux can normally be used direct
from the bag. For non-critical applications, flux may
be stored on the shopfloor in unheated flux hoppers,
provided these are closed units and protect the flux
from open contact with the prevailing atmosphere.
For critical applications, shopfloor storage should
be in heated flux hoppers maintained at 120-150
o
C.
Flux in opened bags, not used during an 8 h period,
should be placed in a storage cabinet or heated flux
hopper, at 120-150
o
C.
Recycling
Unused flux recovered from the welding area must
be cleaned from mill scale, slag, metal particles
and other impurities by use of a suitable fine-mesh
sieve, before being recycled.
Addition of new flux to that being recycled should
be done regularly, in the ratio 1: 3
Redrying
The need for redrying only arises under two
circumstances:
1. If the flux has picked up moisture due to unfavou-
rable storage and handling, and needs to be restored
to its original condition.
2. For critical applications demanding guaranteed
very low weld metal hydrogen levels, redrying of
the flux is recommended.
Redrying should be carried out in an appropriate
oven with free air circulation or purpose made
drier, as follows:
Agglomerated fluxes 300-350
o
C for 2 h
Fused fluxes 150-250
o
C for 2 h
The most important factor here is for the complete
flux bed to reach the given temperature. Redried flux
that is not for immediate use should be stored in a
storage cabinet or heated flux hopper, maintained
at 120-150
o
C.