1. COATINGS FOR STEEL & CONCRETE
Purpose : Concrete to be protected for chloride attack in aggressive environment (marine/Industrial area)

2. STEEL SELECTION & COATINGS
Corrosion resistant steel reinforcement Bass (CRS bars)
Method developed by CECRI (Central Electro Chemical Research Institute Karaikudi, TN)
Inhibited cement slurry coating system
Cement polymer composite coating system

3. Fusion bonded epoxy coated rebar (FBECR)
Hot dip galvanizing
Epoxy - phenolic Interpenetrating polymer network (IPN) coating
Truncated inhibited slurry cement base coating (used in KRCL)

4. CORROSION RESISTANT STEEL
SAIL – HCR bass
TISCO – TISCON – CRS
- TISCON – TMT
They have dual micro structure
with inter surface tempered
& at outer surface Ni, Chromium, Copper & Phosphorous also added.

5. CEMENT SLURRY COATING Derusting – Dipping in acidic, alkaline, water
Phosphating – phosphate jelly for temp protection between de-rusting and cement slurry coating
Cement slurry – 2 coats of OPC cement slurry & inhibitor solution
Cost /MT

6. CEMENT – POLYMER COMPOSITE COATING SYSTEM (CPCC)
Surface preparation – sand blasting
Coating – one coat of Rapid setting primer (dipping or brush)
After 30 minutes – cement polymer sealing coat
Dried for 6 hours
Cost /MT

7. FUSION BONDED EPOXY COATING (FBEC)
Degreasing & Cleaning by shot blasting or grit blasting
Heating – Approx temp 2300
Coating – Bar fed in coating bath where epoxy powder sprayed electrostatically. Epoxy powder melts, flows, gels, cures, cools and produces uniform coating
Forced cooling by water spray
Cost /MT

8. HOT DIP GALVANISING
Galvanising is the process of deposition of zinc over surface of rebars
Removal of oil, grease etc by dipping into caustic solution & rising
Scale rust removed by pickling in H2SO4/HCL & rising with clean water OR
Sand blasting done alternatively
Immerse bars in molten zinc (98.5% pure) at specified temp of 450C
Rebars dried
Successful where carbonation risk is there but not suitable for chloride attach.

9. TURNCATED INHIBITED CEMENT SLURRY COATING FOR DRY CLIMATE
Partial CECRI system
Cost = 500/per MT
Clean by wire brush etc
One coat cement slurry (1 kg cement cc of inhibitor solution) by dipping or brushing
Dry for 24 hrs in shade
2nd similar coat and dry for 24 hrs in shade

10. RECOMMENDED COATING FOR CONCRETE
Aggressive environment
(Sieve, VS, Exten)
Non aggressive environment
Important structure
Other structure
(Mild/Moderate)
Cement – polymer composite crating(CPCC) OR
CPCC OR
Turncated inhibited cement slurry coating
Fusion bonded Epoxy crating
Inhibited cement slurry coating

11. 1st coat of IPN by brush/spray 2nd coat with 4-8 hem Cured for 48 hrs
EPOXY PHENOLIC IPN (INTERPENETRATING POLYMER NETWORK) (Developed by CBRI Roorkee)
Sand blasting
1st coat of IPN by brush/spray
2nd coat with 4-8 hem
Cured for 48 hrs
Epoxy phenolic ipn
Part A – Resin component
Part B – hardener component
Added 1:1 by volume & vigorous stirred for 5-10 minutes

12. COATINGS FOR CONCRETE Epoxy phenolic IPN Crating
Integrated 4 – coat system – CECRI
Epoxy coating
Coal tar coating

13. EPOXY IPN COATING Preparation of IPN polymers Two different resins
A medium viscosity epoxy resin
An aromatic armine
Cross linked & phonotic resin obtained

14. INTEGRATED FOUR COAT SYSTEM
Epoxy polyamide Iron oxide – 1st coat
Epoxy polyamide MiO – 2nd coat (porous)
Epoxy polyamide TiO2 – 3rd coat
Epoxy polyamide aliphatic – 4th coat (tough polymer)
Cost – 320/M2

15. EPOXY COATING Thickness of coating – 8 to 15
Curing by amines or polyamides
They are classified as under
Solvent base epoxy
Thin thixotropic liquid epoxy based primer
Thick epoxy coating applied by spray.

16. COAL TAR FOR EPOXY They have properties of both coaltar & epoxy
Good adhesion with concrete & chemical resistant
Two coats (total thickness 150 – 200 u) applied by rollers or airless spray.

17. SELECTION OF CONCRETE COATING
Aggressive
Non aggressive
Sub structure – coal tar epoxy
Not required
Super structure – Epoxy phenolic IPN or CECRI four coat
Blended cement can be used
Dense concrete with sufficient cover enough
Clean R/f bar be used.