Question about Cs-0.5mo weld-build up

[Abdullah ahmed1]

Guys i need your help to answer the below

We have cs-0.5mo pipe 16mm thickness with heavy external corrosion
I recommended to use 8018-B2 electrod for weld build up with PWHT at 620c


Is the electrod right and do i need higher PWHT temp

 

[weldstan]

It is not necessarily wrong but why not use a matching E7018-A1 filler, a 200F preheat and no PWHT?

 

[Abdullah ahmed1]

I had wps for p3 to p4 i had to use it.
It will be used for 2 years then it will be replaced