Dear Sir,

For one of our application we found the corrosion at valve seat of non return valve of Reciprocating pump having MOC as Duplex stainless steel ( 2205 ).
The details are as follows :

Equipment : Reciprocating pump of material duplex steel ( 2205 carrying MALEIC ACID

Pressure : Suction - 120 psi
Discharge - 4000 psi

Concentration : 32 to 45% mix with 38% normal

The specific gravity of Maleic acid is 1.17 at 30 degrees C

To avoid the corrosion at valve seat we are working on proposal of welding the Hastelloy 22 on duplex steel.

If you could elaborate / comment on above proposal wrt :

- Which welding rod is useful for welding hastelloy 22 on Duplex steel ( 2205 )
- What welding procedure should we follow ? ( GMAW / SMAW )
- Any post weld heat treatment is needed ?
- What should be the weld thk ? ( Weld overlay thk / no. of layers )

Waiting for your reply,

vaiku