SLEDGEHAMMER: This crude method is frequently used in attempts to tighten bolts or studs larger than 1" diameter. It gives little control over the amount of torque, is very inconsistent, and is common cause of hand, arm, leg and back injuries.

THERMAL TIGHTENING: This method employs costly stud heaters which require holes in the bolts/studs. Heat is applied, then the nut tightened. Tightening depends on the shrinkage which occurs as the bolt/stud cools. This is extremely time consuming.

HYDRAULIC TENSIONING: Most hydraulic tensioning schemes (hydraulic nut shown here) are not capable of establishing heavy preloads, can be very expensive, and are not suitable in limited workspaces. Most hydraulic tensioners require extra long studs. Also, bolt tension is lost when the load is transferred to the hex nut.

CRANE WRENCH: For larger nuts, overhead cranes or chain hoists are often used to apply heavy force on large wrenches. This is very inaccurate, awkward, time consuming, and very unsafe. Loosening, when required, can be very difficult.

HYDRAULIC WRENCH: Hydraulic wrenches can provide consistent torque (although 30-40% errors in bolt tension are typical), but are heavy, awkward to place and move and require expensive power units and cumbersome hoses. Using hydraulic torque wrenches may cause thread galling.