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Powermaster® hydraulic nuts

Powermaster® hydraulic nuts

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How a hydraulic nuts works

The operating principle of the purely axial, torsion-free application of a force has been transferred from the tool "bolt tensioning device" to the machine element "nut". In addition to the already familiar advantages of the bolt tensioning device, the hydraulic nut offers an additional time-saving benefit in the assembly and dismantling of machine parts.

Using hydraulic nuts helps you to protect your machine parts because you are able to apply defined clamping and tensioning forces without friction. These benefits result in hydraulic nuts being used for tightening bearings, for clamping rotating components or for pre-tensioning bolts that are difficult to access.

Depending on the specific application, hydraulic nuts are designed with continuous pressure application, a mechanical locking device or temporary pressure application.

Standard designs

hydraulic nuts Typ HMM10121
Typ HMM10121

with annular piston
pressure medium: oil
maximum pressure: 1000 bar
connection thread: G 1/4" axial and radial

hydraulic nuts Typ FMM07121
Typ FMM07121

with annular piston for continuous pressure application
pressure medium: grease
maximum pressure: 700 bar
connection thread: 1/8-18NPT axial and radial

hydraulic nuts Typ HMM04125
Typ HMM04125

with annular piston
rectangular design
pressure medium: oil
maximum pressure: 400 bar
chemically nickel-plated surface

hydraulic nuts Typ FMM07124
Typ FMM07124

as clamping screw
pressure medium: grease
maximum pressure: 700 bar
no additional machine element necessary

hydraulic nuts Typ FMM09127
Typ FMM09127

with control piston
no additional pump required
pressure medium: grease
control piston tangential or axial
20 Nm tightening torque for the control piston

Customized designs

There is a also the option of producing a hydraulic nut according to customer requirements in the following versions:

  • hydraulic nut with annular piston and locking nut
  • hydraulic nut with differential piston, tensioning and locking nut
  • hydraulic nut with differential piston and locking nut
  • clamping flanges

There is a large number of different equipment options for these versions.

Please send us your enquiry.