Dear Experts,

Please advise me the stellite welding (Hardfacing) of cast alloy M35-1 (UNS N24135) Control valve plugs  (Monel 400)
The valve used @ OIL RIG, Design Temperature 600 Degree Centigrade & Design Pressure 150 Bar

Do you have WPS for stellite welding (Hardfacing)
1.   What is the suitable welding method & process

2.   What is the suitable stellite grade for shop and field (Stellite 6, 12, & 21)

3.   During welding  what are the parameters to be considered

4.   How to prevent the hairline cracks

5.   What is the preheat, post heat and PWHT Requirements