In jacketed piping systems, spacer/spider rings are used to maintain uniform annular area and to support core pipe. I understand that the length of jacketed spool may be selected based on buckling critical load limits. With varying lengths of jacketed spools but maintaining the same spacer locations, we get different loads which appear on spacer rings.

I am trying to understand that How limited these loads should be? Sure, it would depend on the material and geometry of spacer ring...... a rod or plate of certain length/thickness may be used.......is there an allowable range for such loads? Just want to know what is the practice in this regard.

Need your experienced thoughts / ideas on the subject matter.

Regards,
SkyofStars