ABSTRACT
Since the compressive stresses in jackbolts can be more than twice the main bolt tension stress, it is important to choose jackbolt materials that can carry the main bolt stress at the corresponding design temperature. There are many materials that can carry high compressive loads at elevated temperatures; the problem is cost. For example, raw material for jackbolts for temperatures to 600°F may cost $1.00/lb. Material for 850°F may cost $3.00/lb; material for 950°F, $5.00/lb; and material for 1000-1200°F, $14.00/lb.
