Product Data Sheet Show all documents

Sika® FerroGard®-325 Duo

Hybrid anode for corrosion mitigation

Sika® FerroGard®-325 Duo is a zinc based discrete sacrificial anode placed outside  concrete repaired areas in reinforced concrete structures which are corroding as a result of chloride ingress.
Sika® FerroGard®-325 Duo is a dual technology anode based on the use of a galvanic anode in both an impressed and sacrificial anode function
Sika® FerroGard®-325 Duo discrete anodes are placed into sound chloride contaminated concrete outside of any concrete repaired areas.
The anode works in 2 phases:
1st phase - an impressed current is driven from the Sika® FerroGard®-325 Duo anode to the steel using a temporary power supply. During this stage, the reinforcement’s passive film is strengthened and aggressive ions are drawn away.
2nd phase - at the end of the 1st phase the power is removed. The anode then acts as a long term sacrificial anode preventing further corrosion.

  • No long term power supply needed
  • A variety of sizes to suit the structure and life expectancy
  • Initially delivers an impressed current using a temporary power supply
  • Creates a passive environment during impressed current activation, draws aggressive ions to the anode and the passive film is strengthened around the reinforcement.
  • Acts as a sacrificial anode without the requirement for an external power supply
  • No long term maintenance
  • Further passivating charge can be applied if required.
  • Minimal long term costs
  • Performance can be monitored
  • Cost effective long term durable corrosion control solution
  • No risk of hydrogen embrittlement ( Design dependant)
Product Data Sheet Show all documents

Usage

  • ONLY TO BE APPLIED BY A SIKA NEW ZEALAND APPROVED CONTRACTOR
  • Targeted or global protection of reinforced concrete structures suffering corrosion damage induced by chlorides and/or carbonation.
  • For reinforced and pre-stressed concrete structures such as bridges, car parks, coastal structures, industrial structures and residential high rise.
  • The treatment of pre-stressed elements, such as bridge beams. This is a unique feature of Sika® FerroGard Duo anode system as there is no risk of hydrogen embrittlement when designed properly.
 

Advantages

  • No long term power supply needed
  • A variety of sizes to suit the structure and life expectancy
  • Initially delivers an impressed current using a temporary power supply
  • Creates a passive environment during impressed current activation, draws aggressive ions to the anode and the passive film is strengthened around the reinforcement.
  • Acts as a sacrificial anode without the requirement for an external power supply
  • No long term maintenance
  • Further passivating charge can be applied if required.
  • Minimal long term costs
  • Performance can be monitored
  • Cost effective long term durable corrosion control solution
  • No risk of hydrogen embrittlement ( Design dependant)

Packaging

25 anodes per box

Colour

Cylindrical zinc core covered in an activated coating, separate white spacers and an integral titanium connecting wire.

Product Details

Product Information

Chemical Base

Zinc compound

Shelf Life

5 years from the date of production

Storage Conditions

Product must be stored in original, unopened and undamaged sealed packaging in dry conditions at temperatures between +5 °C and +30 °C. Always refer to packaging. Do not allow contact with oxidizing materials.

Length

165 mm

Diameter

18 mm

Zinc Weight

270 g
System information

System Structure

Other anode sizes are available with different zinc contents and profile:

Name

Zinc content

Sika® FerroGard®-310 Duo

60 g

Sika® FerroGard®-315 Duo

120 g

Sika® FerroGard®-316 Duo TS120 g
Sika® FerroGard®-320 Duo190 g
Sika® FerroGard®-330 Duo380 g
Technical Information

Charge Capacity

>125 to 1000 kC*

*Dependent on local conditions, including chloride concentration, concrete properties, humidity and temperature.

Current Density

Typically for Sika® FerroGard®-325 Duo, 100 mA/m2* per unit in induced current mode and thereafter 1 to 2 mA/m2* in Galvanic mode.

Application

Application Information

Ambient Air Temperature

+5 °C min

Substrate Temperature

+5 °C min
Application steps

APPLICATION

Reference must also be made to the full Method Statement which is summarised below:

Sika® FerroGard®-325 Duo anodes are installed following guidelines in EN 12696:2012 and CEN/TS 14038-2:2010 (E).

The anodes are typically positioned at a density of 4–9 /m2 of surface concrete. Spacing between anodes: 350–500 mm.

Install into pre-drilled 30 mm diameter holes (depth according to length of anode +30 mm) and using Sika® FerroGard®-300 DuoCrete embedding mortar.

Electrically connect each anode to a feeder wire which runs to the temporary power supply for the impressed current stage of the treatment (typically 1 week). During this period  the anodes will distribute ~50–500 kC/m2 steel surface.

After 1 week remove the feeder wire from the temporary power supply and connect to the reinforcement steel. In this final stage the anodes operate in a galvanic mode maintaining the steel in a passive state.

The size of each treated area on a structure may be varied to suit the client's requirements.

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