High temperature bolting

[asvipin]

I am a beginner in mechanical design.I want to select material for a bolt and nut used in a mechanism. Design temperature is 550 degree Celsius and remaining parts are made of SS316L. So I am planning to use ASTM A453 grade 660 and grade 600 for bolt and nut respectively. But galling point of view whether these combination is good or not ? If not good please suggest good materials

Thanks in advance

 

[XL83NL]

Please provide more background information. Is this for a bolted flange joint? Piping or vessel? What gasket, what pressure (/flange pund class rating)?

 

[asvipin]

Its a small lead screw type mechanism. Rotation of bolt actuates three jaws connected to the nut. Bolt diameter will around 12mm (not finalized). If you are concerned about loading around 8KN compressive loading can come on bolt (continuous load after tightening at a temperature of 550 degree Celsius ).

 

[racookpe1978]

What is your maximum allowed temperature cycle rate (deg C/hr), duration at temperature, number of cycles per year? per month?

 

[asvipin]

Duration at 550 degree Celsius = 3 hr
Number of cycles per month = 4
Maximum allowed heating rate = 50 deg/hr

Design life of other systems are 20 years. If life of this component is less than that replacing it is also possible.