Prestressing


 

Prestressing Equipments

Strand Prestressing Hydraulic Units and Jacks

 

Hydraulic units to control the pre-stressing jacks, consisting of:

High-pressure hydraulic piston pump with high flowrate,  maximum working pressure 350 bar (test pressure 400 bar), controlled by electric three-phase motor of different power, voltage and frequency according to customer requirements.

Hydraulic circuit controlled by a solenoid valve.

Double control of stressing pressure by means of a pressure relief valve and an electric pressure switch that stops the unit to the working pressure requested.

Work pressure gauge and control pressure gauge.

Gauge pressure switch on return circuit.

Electrical panel, acoustic alarm and flashing light during working phase.

Four wheels, of which two swivel.

Oil tank complete with level and temperature indicator.

Equipment completed by Strand Prestressing Jacks, available in 4 different sizes, according the different strand size to be tensioned.

 

Prestressing Units Models

 

  • 2 Way Unit, for the control of 1 single prestressing jack. Machine available also in the “Export” 260 version, able to control only 6 ton jack, for tensioning of small strands
  • 4 Way Unit, for the control of 2 jacks, but 1 pressure circuit, to be set at each jack change
  • Automatic 4 Way Unit, for the control of 2 jacks and with 2 pressure circuits
  • Digital Hydraulic Unit, with digital indicator on panel with 4 set points, ideal for 2 jacks. Possibility to integrate a paper printer of pressure levels and connection with PC through dedicated software.

Optionals Available

 

  • Jack support arm with mechanical or electrical lifting hoist to help maneuver the stressing jack
  • Stress measuring system composed of load cell and digital indicator
  • Service of periodic testing of stressing pump and gauges

 

Single-acting detensioning cylinders

 

Single-acting detensioning jacks with different pushing forces (from 35 to 1000 ton), different strokes (standard is 200mm), chrome-plated stem and liner, complete with anti-leakage safety collar, lifting hook and 3/8’’ connector to hydraulic circuit.

 

Detensioning Hydraulic Units

Hydraulic units to control the detensioning cylinders of a prestressed elements prefabricated manufacturing line.

Hydraulic piston pump with high flowrate that works at a max pressure of 350 bar, ruled by a 3phase electric motor. Hydraulic circuit managed by 1 manual distributor for every cylinder, completed with a regulation valve for the oil flowrate.

Electrical panel, acoustic alarm and flashing light during working phase.

Four wheels, of which two swivel.

Oil tank complete with level and temperature indicator.

 

Pushing-Strand Machines

These machines help and automate the strand laying along the production lines. Our equipment for the pushing of the strands on the prestressing lines can be used interchangeably for 3/8”, ½” or 6/10” strands. Options available:

  • Automatic Shear SuperCut for strand cutting
  • Double radio command
  • Count meters and programming of cut

 

Strand Sheating

In order to neutralize the effect of strands where reduced compression stress is required, the best solution is the use of soft sheating. Easy to apply, please find below the list of different types:

  • Yellow colour soft sheath for 0,6’’ strand only, supplied in 3m packs of 300m
  • Red colour soft sheath for 3/8’’, ½’’, 0,6’’ strands, supplied in 3m packs of 600m
  • Sheath for 3×3 wire, supplied in 3m packs of 1500m

 

Strand Anchoring Clamps

Al Bianchi Anchoring Clamps are re-usable and made from high quality steel and processed through severe heat treatment,which ensure many reuses and long life. Please refer to our Prestressing Catalogue in order to check the different sizes of the clamps, Clamps types are listed below.

 

Clamps Open-Type

Re-usable open-type barrels and wedges are the most commonly used for the prestressing of strands/wires as they are practical/cheap, easy to inspect and service.

 

Automatic Strand Anchoring Clamps

The automatic clamps are easy to apply to the strand thanks to their closed design which helps protecting and keeping the various parts in their working positions

 

Joints for wires and strands

To reduce strands waste, the ideal solution is the coupler. It consists of 2 automatic clamps, whose diameter may vary, connected by a nipple.