For the pressure vessel defined in the problem specified in the table, redesign the bolt specifications to satisfy all of the following requirements.
€¢ Use coarse-thread bolts selecting a class from Table 8€“11 for Probs. 8€“41 and 8€“43, or a grade from Table 8€“9 for Probs. 8€“42 and 8€“44.
€¢ To ensure adequate gasket sealing around the bolt circle, use enough bolts to provide a maximum center-to-center distance between bolts of four bolt diameters.
€¢ Obtain a joint stiffness constant C between 0.2 and 0.3 to ensure most of the pressure load is carried by the members.
€¢ The bolts may be reused, so the yielding factor of safety should be at least 1.1.
€¢ The overload factor and the joint separation factor should allow for the pressure to exceed the expected pressure by 15 percent.
Problem 8-33, the figure illustrates the connection of a steel cylinder head to a grade 30 cast-iron pressure vessel using N bolts. A confined gasket seal has an effective sealing diameter D. The cylinder stores gas at a maximum pressure pg. For the specifications given in the table for the specific problem assigned, select a suitable bolt length from the preferred sizes in Table A€“17, then determine the yielding factor of safety np, the load factor nL, and the joint separation factor n0.

A ............. 20 mm
B ............. 20 mm
C ............. 100 mm
D ............. 150 mm
E ............. 200 mm
F ............. 300 mm
N ............. 10
pg 6 ............ MPa
Bolt grade ........... ISO 9.8
Bolt spec. .......... M12 × 1.75