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PICKLING GEL

During welding of stainless steel the weld and the adjacent area to the weld will become exposed to the air at elevated temperature. The result will be oxidation ranging from light tinting to a blue and black scale. A corresponding chromium depletion in the metal below the oxide also occurs. If this is not removed, corrosion will be the result. Unitor Pickling Gel is used to remove this oxides and the underlying chromium depleted layer. It also removes surface micro slag particles and other contaminates which may cause local corrosion. Pickling restores completely the materials corrosion resistance.

8. Pickling residuals and rinse water should be neutralised to pH-7 i.e. with Neutralising Agent, and then rinsed with water. For the deposit of heavy metals, local water pollution control regulations should be consulted 9. The bottles must be stored in an upright position with the lid tightly closed. Storing temperature 20°C. Storage temperature higher than 45°C must be avoided since this accelerate the ageing process.

Weld

Discoloration/oxidation of surface

Chromium depletion

Application

Pickling products are hazardous substances that must be handled with care. The pickling area should be ventilated. Users should wear protective gloves and face visor. Ref.: Safety Data Sheet. 1. Pretreat oxides; slag and weld defects mechanically, preferably when the welds are still warm and the weld oxides less hard.

2. Give the area to be pickled time to cool down to below 40°C after welding. 3. Organic contaminants such as grease, oil and paint have to be removed. 4. Stir the gel to a smooth consistency and spread a thick layer on to the work piece using the brush supplied. 5. The work piece should be cold when the gel is applied, although the air temperature must not be below + 5°C (41°F). Do not pickle in direct sunlight. 6. The gel should be allowed to remain for at least 50 minutes. For Mo-alloyed steels this time should be extended. If necessary the gel may be allowed to remain on the work piece over night as there is no risk for corrosion. 7. After appropriate time, rinse off the reminding gel using fresh water. If necessary brush the weld with a stainless steel wire brush.

3.01

Stir the gel before use

Apply with the brush

Leave the paste to work

Remove with water

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