Welding A333Gr6 to 4130

[cjgrass]

We need to develop a wps to weld A333 grade 6 to 4130 to ASME XI. Could you help with recommendations for filler metal GTAW root and hot pass and SMAW fill/cap and pre heat. i don't see anything in the welding spec's that calls out PWHT? The material size is 4 inch sch 160.
Thanks in advance.

 

[metengr]

By the way, you mean Section IX. What is the thickness of the base materials above? What service condition - low temp? What is the heat treatment condition of 4130?

You need the answers to the above before you start on a WPS.

 

[weldstan]

Assuming low temp, ERNi-1 and E7018-1. Recommend buttering the 4130 and PWHT prior to making the joining weld.

 

[cjgrass]

Thank you for your responses. The thickness of material is 0.625" 3.5"OD pipe. The MTR states ASTM A519, HOT ROLL-QUENCH-TEMPER. Service is low-temp impacts @-50 required.

 

[metengr]

Ok, I would follow weldstan's recommendation on filler metal. Preheat should be
450 deg F. Butter the 4130 side of the weld joint using the GTAW process, PWHT at 1175 to 1200 deg F. Slow cool, complete the rest of the joint with E7018-1 using SMAW.

 

[cjgrass]

Thank you sirs.

 

[sandeepKumar63]

You can use ER70S-6 for Tig root run. Ask the consumables supplier to provide the filler wire with -50 Deg impact and verify before use that its meet your specification. For fill and cap go with E-7018-1 as recommended by weldstan.
You might get high hardness in the 4130 HAZ with coarse grain which can affect your toughness & NACE requirement if any.
Choose a PWHT temp atleast 30 Deg C below than the tempering temp used for the 4130 HT. Refer your MTC.