Advantages of Stud Tensioning & Hydraulic Tensioners

When you hold a stud or a bolt, it is hard to imagine that this sturdy object can act as a spring. In fact, the fasteners in a bolted joint do just that. They must be stretched at assembly with enough force to keep the joint firmly clamped together when it is placed in service. The joint can fail if the load in the studs is too low, too high, or if it is not uniform from stud to stud.

HTI's Hydraulic Tensioners and Hydraulic Stud and Bolt Tensioning Systems are the simple and efficient answer to this problem. It is the tightening method that will help you control the significant costs resulting from incorrectly tightened studs.

Typical Hydraulic Tensioner Applications Include:

Pipeline Flanges
Pressure Vessels
Valves and Pumps
Manways
Heat Exchangers
Diesel Engines
Cranes
Presses
Steam and Gas Turbines
Shaft Couplings
Coal and Rock Grinders
Catalyst Reactors
Wind Turbines

HTI's Hydraulic Tensioners and Hydraulic Stud and Bolt Tensioning Systems offer these important benefits:

Accurate and Repeatable Stud Loading:

The theory and practice of tightening with Hydraulic Tensioners and Hydraulic Stud and Bolt Tensioners is simple. A Hydraulic Stud Tensioner is a special purpose hydraulic cylinder. The tension it applies to a stud is a direct function of the area of the hydraulic cylinder and the hydraulic pressure supplied by the Pump. Since we closely control these variables, the stud tensioning is highly accurate.

Uniform Stud Loading:

Even loading in each stud is important, especially in applications with gaskets. HTI recommends multiple Hydraulic Stud Tensioners for applications with more than one stud. These Hydraulic Tensioners are inner connected to each other and to the pump. As the hydraulic pressure increases, the tension in each stud is the same, and the flange comes together simultaneously and evenly.

Time and Labor Saving:

Multiple Hydraulic Stud Tensioners, working together, save time. Using Hydraulic Tensioners is usually faster than using hydraulic torque wrenches. Compared to torque, using one Hydraulic Tensioner for every four studs on the flange, or "25% cover" will typically cut the tightening time by fifty percent (50%). With one Hydraulic Tensioner for every two studs, or "50% cover", the time can be cut by an additional one-third (33%).

Ease of Use and Safety:

Hydraulic Tensioners and Hydraulic Stud and Bolt Tensioners have a high power-to-weight ratio. They are lighter, less bulky and much easier to use than torque tools. One operator can work most applications with less effort. The operator handles the Hydraulic Tensioner parts (Load Cell, Puller Bar and Bridge) separately. The weight of any one of these parts is usually significantly less than the weight of the hydraulic wrench, and socket, for the same stud size and tightening capacity.

Hydraulic Stud and Bolt Tensioners are quiet and are safer to use than slugging wrenches or bolt heaters. The air, or hand-operated, Hydraulic Pumps are in-herently explosion proof.

Increased Stud Life:

Hydraulic Stud Tensioning eliminates thread galling and seizing. When using Hydraulic Tensioners, the threads and nut contact surfaces do not see the high contact pressures that cause galling.

Hydraulic Technology can help you find a solution to all of your hydraulic tensioning needs. One of HTI’s solutions is a hydraulic hand pump. Call us at: (936) 494-2000, email or use our contact us form to learn more about HTI and its services.