STG 4000-2K

Electro-hydraulic two-circuit high-pressure automatic control system for fully automatic pressing of hubs onto shafts and separating

Especially for fully automatic pressing and loosening of joints on shafts, Schaaf, GmbH & Co. KG developed the Electro-hydraulic two-circuit high-pressure control system STG 4000-2K. In areas where a 100 % functionality, safety and repeat accuracy is necessary the system performs at its best.

It stops the tightening processes at target/ actual deviations and indicates clearly an error message if the press input was not met. This eliminates hub and shaft damages. While pushing on and extending a hub the pressure transformer and distance measurement sensor constantly monitors and records the process (such as pressure time, pressure way, pressure pressure diagram). The system is designed for the industrial use and is sturdy, compact, maintenance free and durable.

STG 4000 2K


  • 100% fulfilment of the press fitting requirement
  • 100% process control and immediate securing of the stop of the tightening process in plan/actual deviations
  • Error reports in plain text if the process requirements are not complied with
  • No hub damage, no shaft damage
    Permanent monitoring of the pushing and the extension of the hub via a number of pressure transformers and distance measuring sensors.
  • Pressure/time, pressure/distance, pressure/pressure diagrams can be output as a QA protocol
  • Free occupation of parameters for tightening and loosening
  • Robust, compact, maintenance-friendly and long-life construction designed for industrial use
  • Password-protected parameter input
  • Parameterised time control and pressure monitoring for switching pressure free after tightening

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Electro-hydraulic two-circuit high-pressure automatic control system for fully automatic pressing of hubs onto shafts and separating


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STG 4000-2K areas of application


The SCHAAF STG 4000-2K can be extended by the following options, amongst others:

  • Radio remote control
  • A number of radial pressure connections
  • Barcode reader
  • Printer
  • Fully automatic cable roller

Areas of Application

The SCHAAF STG 4000-2K is ideally suited for: Tightening and loosening of oil press fits (e.g., ships‘ propellers, steering units, gearwheels, flywheels, coupling hubs, roller bearings, hydraulic couplings and overload protection devices), where 100% sequence of function, safety and repeat precision are necessary.


Quality Assurance

All STG 4000-2K are checked for 100 % process security. During order handling, they are accompanied by ongoing quality assurance measures and supplied with extensive documentation.



The SCHAAF STG 4000-2K are user-friendly, safe and correspond to the latest technical know-how. Our highly motivated employees will be pleased to coach your staff in working with the automatic control system and general interconnections in the press fit in situ or at our works.

In this way, all the process parameters can be entered optimally in order to achieve maximum process monitoring and safety. Naturally, the STG 4000-2K are supplied ready for operation.

Related Accessories

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High-pressure generators optimally matched to our high-pressure tools.

Hydraulic high-pressure accessories specially adapted to the function.


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Industry-specific special solutions:

All SCHAAF products offer an individual solution for every industry.

STG 4000-2K proves particularly effective for:

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