Covered Electrodes For Stainless Steel

Stainless Steel Welding Consumables IntroductionCovered Electrodes

 

1.Welding Consumables Selection and Recommendation


  Definition of Stainless Steel materials according to AWS: The content of chromium (Cr) > 12% the Fe content higher than other alloys. Welding material is mainly based on a match of the parent material, the engineering design requirements, the environment of the workpieces, and any other requirements of PWHT and welding methods as a basic selection.

 

  It belongs to the field of the iron-based high alloy steel, the heat input control, the preheat temperature, and the weld temperature between the welds all are relatively important, in order to avoid excessive burning of components, carbonation over-precipitated to reduce corrosion resistance, grain over-extensive, structural brittle phase precipitation and other problems.


  It is due to the engineering requirements for the Austenitic stainless steels; it is usually specified the content of ferrite number (Fn). The measures are generally testified under Ferrite Detector (real measures), the table lookup (table of the chemical composition), and metallographic analysis.

 

  Classification of Stainless Steel covered metal arc welding specification according to AWS A5.4, is based on the composition, welding current, and welding position, but without the information of tensile strength on specification. The following is an overview of the relevant classifications and applications:


 

Classification

Welding Current

Welding Position

Features & Applications

EXXX(X)-15

DC(+)

All

  It is usually designed for basic covered fluxes, spatters, and slag removal worse than -16, but better mechanical properties, generally used at -196℃ the super-low temperature environment.

EXXX(X)-16

AC & DC(+)

All

  General types for titanium oxide low hydrogen covered design.

EXXX(X)-17

AC & DC(+)

All

  It replaces Ti with Si on design for covered electrodes in order to obtain finer transition droplets and weld flatness, especially in the vertical and overhead welding the weld convexity more even than -16

EXXX(X)-26

AC & DC(+)

F,H-Fillet

  The welding material for the horizontal fillet welding for excellent weld flatness.


Marks: For all welding positions, the vertical and overhead welding positions recommended using ≦4.0mm

 

 

2.Welding Operation Points:


(1)Storage Management


①It requires an appropriately dry warehouse for storage in order to avoid high humidity (≧80% R.H) and high heat temperate (≧30℃) coexisting environment, resulting in the excessive moisture absorption on the electrodes.

 

Most of the stainless steel covered electrodes are low-hydrogen system, which must be dried at high temperature prior to use, and placed in a thermostat-container or a low temperature oven at 100~150℃ for storage. Use with a small amount each time from the storage to reduce the moisture concerns in the covered flux for the weld blowhole matters. Please refer to the instructions of the dry conditions in the appendix.

 

 

(2)Welding Precaution


①The core rod of the stainless steel covered electrode is mostly made of stainless steel material. The slower heat conductivity and higher coefficient expansion, and therefore, it causes the resistance of the core rod at height while the excessive welding current through; the covered flux generates heat in red and the condition of flux comes off. 

 

When the welding current is excessive or the welding speed too slow, it causes the chromium carbide precipitation, the structure brittleness, the corrosion resistance and cracking on the weld.

 

Oxidation film, water vapor, oil pollution, skin, surface spraying and other intermediates on the parent metal workpiece that would increase the gas content of the weld metal and cause the blowhole on the weld. Besides, cleaning the surface of the workpiece prior to welding.

 

It maintains a short arc welding in order to avoid water vapor and nitrogen dissolved into the weld that generates blowholes.

 

The swing arc may not exceed 3 times of the electrode diameter while welding by weaving mode to ensure the melting quality of the weld. 

 

The deformation of the workpiece after welding is bigger than carbon steel materials. Therefore, it requires a jip and symmetrical welding method to prevent the workpiece deformed.

 

Outdoor welding, it requires wind protection process if the wind speed exceeds 3 m/s, in order to avoid the outside air/gas into the weld that generates blowhole matters.

 

⑧Preheat and weld temperature suggests to maintain at 16~150℃ while welding in Austenitic Stainless Steel, the rest in accordance with welding regulations and WPS.

 

⑨When weld a dissimilar material joint by stainless steel 309, the carbon equivalent or the excessive dilution rate matters of the parent metal is to cause the weld cracking. Therefore, it requires a low heat-input welding or surface spreading on carbon steel/alloy steel/cast iron ahead, and then does weld two different parent metals.

 

⑩Without the content of ferrite in full austenitic stainless steel, it is strictly required the heat input for the hot cracking matter on the weld. 

 

View:

SS-309

不銹鋼SMAW銲接
AWS A5.4 E309-16
JIS Z3221 ES309-16
EN --
GB T983 E309-16

SS-308LT

不銹鋼SMAW銲接
AWS A5.4 E308L-16
JIS Z3221 ES308L-16
EN ISO 3581-A E 19 9 L R 1 2
GB T983 E308L-16

SS-308

不銹鋼SMAW銲接
AWS A5.4 E308-16
JIS Z3221 ES308-16
EN ISO 3581-A E 19 9 R 1 2
GB T983 E308-16

SS-307HM

不銹鋼SMAW銲接
AWS --
JIS --
EN --
GB --

SS-307

不銹鋼SMAW銲接
AWS A5.4 E307-16
JIS Z3221 ES307-16
EN ISO 3581-A E 18 9 MnMo R 1 2
GB T983 E307-16

SS-309Nb

不銹鋼SMAW銲接
AWS A5.4 E309Nb-16
JIS --
EN --
GB T983 E309Nb-16

SS-312

不銹鋼SMAW銲接
AWS A5.4 E312-16
JIS Z3221 ES312-16
EN ISO 3581-A E 29 9 R 1 2
GB T983 E312-16

SS-316

不銹鋼SMAW銲接
AWS A5.4 E316-16
JIS Z3221 ES316-16
EN ISO 3581-A E 19 12 2 R 1 2
GB T983 E316-16

SS-316LT

不銹鋼SMAW銲接
AWS A5.4 E316L-16
JIS Z3221 ES316L-16
EN ISO 3581-A E 19 12 3 L R 1 2
GB T983 E316L-16

SS-318

不銹鋼SMAW銲接
AWS A5.4 E318-16
JIS Z3221 ES318-16
EN ISO 3581-A E 19 12 3 Nb R 1 2
GB T983 E318-16

SS-347

不銹鋼SMAW銲接
AWS A5.4 E347-16
JIS Z3221 ES347-16
EN ISO 3581-A E 19 9 Nb R 1 2
GB T983 E347-16

SS-385

不銹鋼SMAW銲接
AWS A5.4 E385-16
JIS Z3221 ES385-16
EN ISO 3581-A E 20 25 5 Cu N L R 1 2
GB T983 E385-16

SS-410

不銹鋼SMAW銲接
AWS A5.4 E410-16
JIS Z3221 ES410-16
EN ISO 3581-A E 13 R 1 2
GB T983 E410-16

SS-430

不銹鋼SMAW銲接
AWS A5.4 E430-16
JIS Z3221 ES430-16
EN ISO 3581-A E 17 R 1 2
GB T983 E430-16

SS-2209

不銹鋼SMAW銲接
AWS A5.4 E2209-16
JIS Z3221 ES2209-16
EN ISO 3581-A E 22 9 3 N L R 1 2
GB T983 E2209-16

SS-2594

不銹鋼SMAW銲接
AWS A5.4 E2594-16
JIS --
EN ISO 3581-A E 25 9 4 N L R 1 2
GB T983 E2594-16

SS-2595

不銹鋼SMAW銲接
AWS A5.4 E2595-16
JIS --
EN ISO 3581-A E 25 9 4 W N L R 1 2
GB T983 E2595-16

SS-308H

不銹鋼SMAW銲接
AWS A5.4 E308H-16
JIS Z3221 ES308H-16
EN ISO 3581-A E 19 9 H R 1 2
GB T983 E308H-16

SS-309MoL

不銹鋼SMAW銲接
AWS A5.4 E309LMo-16
JIS Z3221 ES309LMo-16
EN ISO 3581-A E 23 12 2 L R 1 2
GB T983 E309MoL-16

SS-317L

不銹鋼SMAW銲接
AWS A5.4 E317L-16
JIS Z3221 ES317L-16
EN --
GB T983 E317L-16

SS-410NM

不銹鋼SMAW銲接
AWS A5.4 E410NiMo-16
JIS Z3221 ES410NiMo-16
EN ISO 3581-A E 13 4 R 1 2
GB T983 E410NiMo-16

SS-308L

不銹鋼SMAW銲接
AWS A5.4 E308L-16
JIS Z3221 ES308L-16
EN ISO 3581-A E 19 9 L R 1 2
GB T983 E308L-16

SS-309L

不銹鋼SMAW銲接
AWS A5.4 E309L-16
JIS Z3221 ES309L-16
EN ISO 3581-A E 23 12 L R 1 2
GB T983 E309L-16

SS-310

不銹鋼SMAW銲接
AWS A5.4 E310-16
JIS Z3221 ES310-16
EN ISO 3581-A E 25 20 R 1 2
GB T983 E310-16

SS-316L

不銹鋼SMAW銲接
AWS A5.4 E316L-16
JIS Z3221 ES316L-16
EN ISO 3581-A E 19 12 3 L R 1 2
GB T983 E316L-16