Påførelse af Zinga

Surface Preparation
It cannot be stressed strongly enough that the key to Zinga’s long life is in the thorough preparation of the steel substrate to the correct specification. Please always follow the appropriate Zinga UK specification in conjunction with the Zinga Application Data Sheet although the following gives a general guide.

Firstly the surface will require to be decontaminated by steam cleaning or high pressure washing to completely remove salt, grease, old paint, loose particles etc.

With marine structures, all crustacean growth must be removed from the steel’s surface before the degreasing process begins, and not after.

If the Zinga is to be applied to old, worn galvanising, metallising or old Zinga then all that is required after decontamination is to ensure that there are no loose particles on the surface. Please contact Zinga for a full specification.

If, however, the steel is either new or has not previously been galvanised then, after washing, the surface will require to be grit blasted to a cleanliness standard of Sa 2.5. The grit used should be carefully chosen to achieve the blast profile outlined in the appropriate specification (normally between 50 and 80 microns depending on application). The chosen grit should always be able to achieve a blast roughness of 12.5 to 15 microns. It should be noted that UHP Blasting does not create a profile and should therefore not be used as the sole means of surface preparation.

 

Application
Once thoroughly mixed, Zinga can be applied by using a normal paintbrush, a short-fibre roller (not for the first coat) or a conventional or airless spray-gun. When applying Zinga by spraying it must only be thinned with Zingasolv, which is available from your nearest distributor. Please read the appropriate Application Data Sheet.

Zinga can be applied in a wide variety of weather conditions . The application surface temperature range is from -15C to +60C where conditions allow with a maximum humidity of 95% so long as there is 3C minimum between the steel temperature and the dew point. Like all coatings the substrate surface should be free from all types of contamination. Please seek advice from the Zinga UK Technical Department for extreme application environments.

The broad range of allowable application conditions that Zinga affords means that very few days are lost during projects due to poor weather i.e. the maintenance window is extended. This, combined with Zinga’s unlimited pot and shelf life, ensures minimal wastage of either time or materials during a project.

 

Coverage
Please click here for a sheet detailing the theoretical coverage and consumption of Zinga. In practice the quantity of Zinga required to coat a given area is dictated by both the required dry film thickness (dft) and the depth of the blast profile. The table below can be used to roughly estimate the quantity of Zinga required in kilograms (kg) to cover one (1) square metre assuming zero (0%) wastage. We have been informed by applicators that this chart overestimates the quantity required even when halving the wastage factor normally used but it does provide an approximate guide.

Area = 1m Blast Profile (Microns)
Dry Film Thickness (Microns) 40 60 80
60 0.54 0.59 0.65
80 0.68 0.73 0.79
100 0.82 0.88 0.93
120 0.96 1.02 1.07
160 1.24 1.30 1.36
200 1.53 1.58 1.64

Curing Mechanism and Drying Times
Once dry, Zinga requires exposure to fresh air and moisture to become fully cured. The natural porosity of the coating is dramatically reduced as curing takes place and Zinga continues to harden for a few weeks after application. Although rainwater is sufficient to trigger the curing mechanism, the process can be further accelerated by saturating the coating with fresh water using a fine water mist (Please see Water Saturation Procedure).

It is vital to note that before exposure to a saline environment (i.e. submerged in salt water or placed in a salt spray zone) any Zinganised surface will require saturation with fresh water for a minimum of two hours to properly seal it. If the coating is unlikely to be immediately exposed to salt then exposure to rain water over time will have the same sealing effect.

Approximate Drying Times (45µm dft) @ 20C:

  • Touch dry in 10 minutes
  • Dry to handle in 30 minutes
  • Dry to overcoat with Zinga in 60 minutes
  • Cured to overcoat with water-based paints in 4 hours
  • Cured to overcoat with epoxy in 24 hours

N.B. Please see notes on the Zinga Application Data Sheet for greater detail.
Topcoats
Please always strictly adhere to the appropriate specifications provided by the topcoat manufacturers in conjunction with the correct Zinga UK specification relating to the individual application.

Although Zinga can be easily over-coated with a wide range of topcoats, it should be noted when using epoxies etc. that Zinga is sensitive to solvents and all the necessary precautions should be taken to minimise its exposure to any solvents contained in the topcoats. Zinga UK regard the use of the “mist-coat/full-coat” technique as vital to prevent this happening. An MIO or equivalent epoxy sealer should first be applied in a very fine mist coat (no greater than 20-30µm) which when cured, seals the Zinga and provides a barrier to the solvent in the subsequent coat. The second full-coat of the tie-coat can be applied at the same d.f.t. as before but tight control is required to ensure the maximum combined d.f.t. of 90µm is never exceeded. Please observe the relevant manufacturers drying and curing times for the tie-coat before proceeding on to the top-coats. This is vital to ensure that all the solvent has evaporated and minimises the potential for solvent entrapment.

Some paint companies sell epoxies which are specifically designed for use as tie-coats. The resins that are used in these tie-coats are “thin” resins; hence they do not require the addition of solvent prior to spray application. Normal epoxies which do require solvent to be added before application must not be used as they increase the potential for solvent entrapment. Avoid this problem by always using a proper tie-coat.

Paint manufacturers normally specify individual primer/top-coat systems and these should always be adhered to and applied over the tie-coat.

Topcoats to avoid using in conjunction with Zinga include all alkyd-based enamels, which must never be applied over any zinc based coatings. It should also be noted that cellulose lacquers cannot be applied directly onto Zinga and an automotive MS primer must be used beforehand. High-build vinyls and chlorinated-rubber paints are extremely high in solvent content so the advice of the previous paragraphs is particularly relevant. Zinga UK recommend, where possible, the use of water-based topcoats to complement the environmentally friendly properties of Zinga.

Alufer N (another Zingametall product – see Product Range) is widely used to seal the Zinga prior to the application of topcoats.

Zinga is a truly unique coating product so if you have any query relating to compatible topcoats please contact the Zinga UK Technical Department.

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Info

Zinga Danmark

Lundborgvej 1,

8800 Viborg

info@zinga.dk

Hvorfor vælge Zinga?

Zinga kombinerer kathodisk- (galvanisk) og barrierebeskyttelse.
Det er nemt at påføre.
Kan påføres selv i dårligt vejr.
Kan påføres en renset, rustet overflade.
Zinga behøver kun minimal forberedelse af overfladen før påføring.
Har en kort tørretid.
Zinga flager ikke af, og bliver ikke skørt.
Zinga kan genlades ved efterfølgende behandling.
Zinga er ideelt til behandling af lokale skader, selv efter svejsning.

Certificeringer

Zinga Koldgalvanisering, har været brugt i over 30 år, i en lang række forskellige brancher, hvorfor der er opbygget en betydelig erfaring omkring brugen af denne.

Zinga er desuden certificeret efter en række standarder, bl.a. ISO 12944 og NORSOK Standard M-501.

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Kontakt

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