Stainless Steel Welding Consumables Introduction—Flux-cored Wire
1.Welding Consumables Selection and Recommendation：
Specification of stainless steel flux-cored wire arc welding according to AWS: It is based on welding wire types, composition, welding positions, and gas shield types. The information of the tensile strength is not shown on specification. The welding wire meets the specification of side expansion ≧ 0.38mm at -196℃ when required; the letter “J” in the latter specification plus. The following relevant classification and application：
|
Classification |
Welding Method |
Gas Shield |
Current |
Welding Position |
Feautres & Applications |
|
EXXXTX-1 |
FCAW |
100%CO2 |
DC(+) |
EXXXT0-X： Flat & Horizontal welding
EXXXT1-X：
All position |
CO2 as gas shield for general welding materials |
|
EXXXTX-3 |
FCAW |
-- |
DC(+) |
Self shielded materials are generally designed to T0 grade. |
|
|
EXXXTX-4 |
FCAW |
75~80%Ar+
20~25%CO2 |
DC(+) |
Mixed gas shield possesses better welding control and weld balanced. |
|
|
EXXXTX-G |
FCAW |
not specified |
not specified |
Special purpose design |
|
|
RXXXT1-G |
GTAW |
not specified |
not specified |
All |
Special purpose design |
|
RXXXT1-5 |
GTAW |
100%Ar |
DC(-) |
All |
TIG flux-cored wire for pipeline bottom-welding, not recommended for surface welding due to blowhole and slag risks. |
|
ECXXX |
FCAW |
98%Ar+2%O2 |
DC(+) |
not specified |
Metal-cored wire possesses better deposition rate and lower depth penetration than solid wire. |
|
ECXXX |
GTAW |
100%Ar |
DC(-) |
All |
TIG metal-cored wire with no slag. |
2.Welding Operation Points：
(1)Storage Management：
Related to the storage management refers to the instruction of carbon steel flux-cored wire.
(2)Welding Precaution：
①The recommended length of the wire extension is in the range of 15~20 mm, the shorter may cause the
high melting point substance undissolved up in the flux that generates wormholes matter on the surface of the weld.
②Use mixed gas shield is better operation control and weldmetal composition balanced than CO2 when it reaches the critical condition the arc spray formation. Besides, the matchup of voltage and current, the length of wire extension no less than 15mm is to avoid wormholes on the surface of the weld.
③In addition to the guidelines of TIG rod welding when the bottom welding with the TIG flux-cored rod for full penetration welding, the matter of the slag on the top of the molten iron involved into the weldpool should be a subject in consideration.
④The tension of the stainless steel wire is larger than the carbon steel wire, and therefore, the conduit of the welding gun should not be over-bending while wire feeding. The inner conduit may not be shared with carbon steel wire in order to avoid contamination of the powder from the wire surface or drawing oil.
⑤It requires a low heat input and the welding swing width≦25mm when use flux-cored wire for the bottom-welding, in order to avoid excessive dilution rate resulting in the lower alloy content of the weld, the weld overlapping width between the welds recommended at 1/2 weld width from each.
⑥The rest, refer to the precautions of stainless steel covered electrode.
