How much torque do I use? The proper amount of bolt tightness is essential for consistent leak-tight performance of otherwise properly designed Bolted Flange Joint Assemblies. "How much torque?" is a common question in industry and this is the most covenient torque calculator ever made. Alltite's new iPhone app will let you quickly and easily determine a torque specification for any standard sized ANSI flange or bolt / stud size. You can quickly slide your finger to select from a variety of stud materials, lengths, diameters and other factors such as lubricant used. The torque values are based on K factors and not just the coefficient of friction so the torque values you receive are based on science and laboratory results. Our handy cross-reference tool lets you start out by either the ANSI flange size and class or directly from stud size. Other useful features include nut sizes, flange specifications such number of bolts, bolt hole diameters, flange thickness and other helpful benefits.