I have always heard that for assembly of bolted joints in heat exchanger, pressure vessel etc, it is always better to use Nickel Based Lubricant compound versus Copper based or Moly based. I am talking with reference to application in a conventional Petroleum Refinery only. Bolting material being B7, B16, B8. Does anyone know why nickel based lubricant would make a better choice vs copper or Moly based.
Thanks
