How Many Stud Tensioners Do I Need?
You can tension most applications with one Hydraulic Stud Tensioner. Using additional Tensioners gives the benefit of even flange closure and speeds up the job. Thus, on applications with multiple studs, HTI recommends using enough Hydraulic Stud Tensioners to provide between 25% and 50% “cover”. This means one Hydraulic Stud Tensioner for every fourth, or every other, stud.
With less than 25% cover, the tensioning should usually be done in three steps. That is, one pass around the pattern at one-third tension, a second pass at two-thirds tension, and a final pass at full tension. With 25% or more cover, the studs can usually be taken to full tension in one pass, significantly reducing the processing time.
Stud Tensioners for Circular Flanges
On circular flanges, HTI recommends using at least four Hydraulic Stud Tensioners and, preferably, 25% or 50% cover. For example, on a flange with 36 studs, use four, nine (25% cover), or eighteen (50% cover) Hydraulic Stud Tensioners. For accuracy and speed, some applications require 100% “cover”.