Tankguard Zinc

Product description

Tankguard Zinc is a two-pack, moisture curing, ethyl silicate based zinc-rich lining that complies with the compositional requirements for SSPC Paint 20 level 1 and ISO 12944. This product is supplied with ASTM D520 Type II zinc dust.

Recommended use

As a lining for protection of tanks for chemicals and potable water onshore, offshore and on ships. A separate resistance list is available. Resistant to cyclic dry temperatures up to 400ºC.

Film thickness and spreading rate

                                                                                         Minimum                  Maximum                    Typical

Film thickness, dry (µm)                                               50                               170                              100

Film thickness, wet (µm)                                              75                               250                              150

Theoretical spreading rate (m²/l)                             13,4                              3,9                                6,7

Approvals

The Norwegian Institute of Public Health (Nasjonalt Folkehelseinstitutt) has approved Tankguard Zinc for use in contact with potable water.

Physical properties

Colour Grey

Solids (vol %)* 67 ± 2

Flash point 16ºC ± 2 (Setaflash)

VOC 463 gms/ltr UK-PG6/23(97). Appendix 3

Gloss Flat

Water resistance Very good

Abrasion resistance Excellent

Solvent resistance Excellent

Chemical resistance Excellent within pH-range 6-10

Flexibility Good

*Measured according to OCCA Monograph No. 4

Hong Kong rules:

Category of paints -Tank lining coatings; VOC 500 gms/ltr HK EPD method (Ready to use); Exempt compound - N/A; Specific gravity: 2.59 gms/ltr (A+B); Both VOC and Specific gravity values provided are typical values, subject to changes when different colour involved.

Surface preparation

All surfaces should be clean, dry and free from contamination. The surface should be assessed and treated in accordance with ISO 8504.

Bare steel

Cleanliness: Blast cleaning to Sa 2½ (ISO 8501-1:2007). Roughness: using abrasives suitable to achieve grade Fine to Medium G (30-85 µm, Ry5) (ISO 8503-2)

Other surfaces

The coating may be used on other substrates. Please contact your local Jotun office for more information.

Condition during application

The temperature of the substrate should be min. 5°C and at least 3°C above the dew point of the air, temperature and relative humidity measured in the vicinity of the substrate. Zinc ethyl silicate paints require moisture for curing. At low humidity the curing will be improved by gently sprinkling fresh water over the paint film, and/or by artificial humidification of the surrounding atmosphere.

Application methods

Spray Use airless spray or conventional spray

Brush Recommended for stripe coating and small areas, care must be taken to achieve the specified dry film thickness.

Application data

Mixing ratio (volume) 3:1

Mixing 18,5 kg/2,6L Jotun Zinc 100, Comp B (zinc dust) to be poured slowly into 7,8 litres Tankguard Zinc Comp. A (Base) during mechanical mixing. Stir until lump free and pass through a 60 mesh sieve.

Pot life (23°C) 8-12 hours (Reduced at higher temp.)

Thinner/Cleaner Jotun Thinner No. 4/25

Guiding data airless spray

Pressure at nozzle 10 MPa (100 kp/cm², 1400 psi)

Nozzle tip 0.46-0.58 mm (0.018-0.023")

Spray angle 30-80°

Filter Check to ensure that filters are clean.

Note Adjusting spray pattern and drying may sometimes become necessary. Use max 5% Jotun Thinner No. 4 (fast evaporation) when temperature is low and Jotun Thinner No. 25 (slow evaporation) when temperature is high.

REMARKS: Thinner should be added after mixing components.

Drying time

Drying times are generally related to air circulation, temperature, film thickness and number of coats, and will be affected correspondingly. The figures given in the table are typical with:

• Good ventilation (Outdoor exposure or free circulation of air)

• Typical film thickness

• One coat on top of inert substrate

* Relative humidity at 5°C: 80%, at 10°C: 70%, at 23°C: 60%, at 40°C: 50%

1. Fully cured film to be verified by MEK test (ASTM D 4752-87) and Coin test: Scrape the coating fiercely with a coin, a shining metallic lustre indicates a through cured coating.

1. For touch up by itself only. Touch up coating to be thinned 15% with Jotun Thinner No. 25

2. Provided the surface is free from zinc salts and other contamination prior to application, there is normally no overcoating time limit. Best intercoat adhesion occurs, however, when the subsequent coat is applied before preceding coat has cured.

The given data must be considered as guidelines only. The actual drying time/times before recoating may be shorter or longer, depending on film thickness, ventilation, humidity, underlying paint system, requirement for early handling and mechanical strength etc. A complete system can be described on a system sheet, where all parameters and special conditions could be included.

Typical paint system

For interior of tanks:

Tankguard Zinc 1 x 100 µm (Dry Film Thickness)

Other systems may be specified, depending on area of use

Complete curing :

Tankguard Zinc must be completely cured before the tank is put into service. In order to achieve this the following procedures can be used:

Apply 100 µm Tankguard Zinc

Let the paint dry/ cure with good ventilation for 4 hours at 80-90% relative humidity and minimum 5°C.

Spray water (seawater is preferred) on the coating and leave the tank closed. Repeat the water spraying 3 - 4 times during a 48 hours period

Remove the water and let the tank dry.

Complete curing should be verified by MEK test (ASTM D 4752-87) and Coin test: Scrape the coating fiercely with a coin, a shining metallic lustre indicates a through cured coating.

Storage

The product must be stored in accordance with national regulations. Storage conditions are to keep the containers in a dry, cool, well ventilated space and away from source of heat and ignition. Containers must be kept tightly closed. The component A must be stored below 25°C. The product component B is zinc dust and has no strict limitation's for storage. SHELF LIFE: 6 months at 23°C for Comp. A. , 4 years for comp. B, subject to re-inspection thereafter. Higher temperatures during storage may reduce the shelf life and may lead to gelling in the tin.

Handling

Handle with care. Stir well before use. Continuous stirring during application will prevent the heavy zinc pigment from settling.

Packing size

10.4 litre unit: 7.8 litres Comp. A in a 10 litre container and 18,5 kg/2,6 litres Jotun Zinc 100, Comp B (zinc dust) in a 20 litre container.

Health and safety

Please observe the precautionary notices displayed on the container. Use under well ventilated conditions. Do not breathe or inhale mist. Avoid skin contact. Spillage on the skin should immediately be removed with suitable cleanser, soap and water. Eyes should be well flushed with water and medical attention sought immediately.