smartTensioner BoltTensioner Configurator

Maximal stroke

The maximal stroke descibes the max. movement of the BoltTensioners piston. It should be sufficient to cover setting effects in the flange conatct surfaces as well of plastig behaviour of the sealings. Especially hollow metal sealings require some way.
We recommend to use our automatic PistonStrokeLimitation (see opotions below) to avoid excessing the max. stroke.

Maximum foot print

The contact pressure between the BoltTensioner and your application should be monitored carefully. If it is too high, the surface of your parts might be damaged. If you provide us with information about the material of your contact part (e.g. flange), we will be happy to assist you.


If the contact pressure is too high but the diameter can not increased anymore due to geometric restrictions, we will mill the spacer on both sides. This allows low contact pressure in combination with 100% tensioning.

After reaching target pressure and the max. axial bolt force, the nut is turned manually using a torque wrench turning the integrated 1/2" shaft adapter. The gear drive has been designed for rough and difficult environments allowing to loosen even rusty or dirty nuts. The adapter shaft and the gears are made of high grade steel. The maximum torque applying to the nut, depending on the thread size, is about 300Nm. Using a cordless nutdriver is also possible.

After reaching target pressure and the requested axial bolt force, the nut is turned manually using a tommy bar and the integrated nut adapter that encloses the hexagonal nut..

After reaching target pressure and the maximum axial bolt force, the nut is turned automatically by an integrated high-torque motor. Controlled by the integrated pump, the Automatic NutGearDrive allows operating the whole tensioning and de-tensing process without any manual interaction. In addidtion, during the tensiong process the nut is stepwise tightend while the pressure is slightly realeased. This is the fastest way to tension a bolt and to get the lowest setting losses. More information is available on request.

The gears are made of high grade steel. If the provided motor torque should not be sufficient, an additional 1/2" shaft adapter allows turning the nut with a wrench.

Manual piston return

After use, the piston of the BoltTensioner might not be in it's initial position. It therefore needs to be pressed back using an appropriate press, e.g. with a plain vice (not included). We only recommend this option for seldom used tensioners.

Spring piston return

Since all smartTensioner BoltTensioeners feature an integrated pump, the overall amount of oil in our hydraulic systems is very low. This allows us to use integrated springs to automatically pull the piston back in it's initial position after use. This system does not need any manual interaction. The BoltTensioner is always ready to use.

Hydraulic piston return

For bigger tensioners or tensioners with long stroke, we recommend our HydraulicPistonReturn-system. After manually operating an integrated valve, the pump is used to press the piston back in it's initial postion. More information available on request.

Small Pump - 1

Our smallest pump recommended for threads up tp M36 / 1 1/2". Weight: 1.5 kg. All pumps include a sophisticated torque-motor in combination with a pressure sensor. The maximum pressure (correspinding to the maximum bolt force) can be adjusted. In operation, the pump display shows the current pressure. The pump functions can be controlled using the integrated panel or an external, weireless control device with the smartTensioner Software.

Medium Pump - 2

Our medium pump recommended for threads up tp M72 / 3". Weight: 2.5 kg. All pumps include a sophisticated torque-motor in combination with a pressure sensor. The maximum pressure (correspinding to the maximum bolt force) can be adjusted. In operation, the pump display shows the current pressure. The pump functions can be controlled using the integrated panel or an external, weireless control device with the smartTensioner Software.

Large Pump -3

Our biggest pump recommended for threads bigger than M72 / 3". Weight: 4.0 kg. All pumps include a sophisticated torque-motor in combination with a pressure sensor. The maximum pressure (correspinding to the maximum bolt force) can be adjusted. In operation, the pump display shows the current pressure. The pump functions can be controlled using the integrated panel or an external, weireless control device with the smartTensioner Software.

The AutomaticOutletValve allows operating the pump pressure valve automatically or with our (wireless) pump control software. It is very useful if at some point during the tensiong process the individual BoltTensioner pressure needs to be reduced, e.g. for tensiong many bolts at once in certain pressure steps.

The AutomaticOutletValve is required for fully automated bolt tensioning.

The NutAdapterSpring allows to mount the BoltTensioner in any position of the hexagonal nut. If the nut adapter should not match the nut, it is shifted upwards. After the turnimng the adapter, it will glide on the nut supported by a spring.

The PistinStrokeLimitation is a strongly recommended feature: If the piston should be moved beyond it's allowable stroke, it might leave the cylinder. With smartTensioner, this is not dangerous situation because the amount of compressed oil is very low and no elastic components (hoses) are used. However, pressing the piston back will destroy the sealings. The PistonStrokeLimitation automatically stops the pump when the piston has reached it's max. position.

Our pumps can be operated by a small panel on the top of the pump. However, using several pumps at once is easier using our smartTensioner pumpControl-Software: Available on a tablet PC (included), it allows controlling all pumps at once and synchronizes the pumps against each other to ensure even force distribution. More information available on request.