B7 Studbar is commonly used in pipe flange connections.  We sell 6 foot lengths but can also cut to your required length.  ASTM A193 Plain finish   B7 has similar strength to SAE grade 5 fasteners, however, it is specifically used in high temperature and pressure applications.   Thread = 8 TPI for diameters larger than 1"      A Certificate can be requested at the time of ordering.