CoatingsPro Magazine

MAY 2015

CoatingsPro offers an in-depth look at coatings based on case studies, successful business operation, new products, industry news, and the safe and profitable use of coatings and equipment.

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COATINGSPRO MAY 2015 25 4. What is the next coat of the system, and what is its recommended DFT? If the topcoat is a thick film that normally cures with strong cross-linking, such as a tank lining, the curing reaction of the topcoat could cause a cohesive split in that thick primer. 5. Most importantly, how thick is that primer? Anytime a coating is applied at more than 25 percent above its recommended thickness, stress is being built up in that film. Stress will find a way of relieving itself, usually when the steel flexes for one reason or another. This does not mean that it will crack at small increments in thickness above the recommended thickness plus 25 percent. It simply means that the possibility of crack- ing increases with the thickness of that primer. Priming Tank With Zinc Silicate Coating Q: I have the following questions related to zinc silicate and its subsequent coat: 1. What is the maximum over-coating interval for zinc silicate paint? We have completed full roof plate paint- ing and priming of a tank applying zinc silicate paint as primer. 2. What is the maximum permissible metal temperature during paint application for zinc silicate? Current metal temperature during paint application is found to be around 50° F (10° C). So what should be the percentage of extra thinning? 3. What should be the maximum permissible metal temperature and the percentage of extra thinning for intermediate coats? A: You really need to discuss this with the technical service repre- sentative of the coating manufacturer, not the sales representative. I assume you are using solvent-borne inorganic zinc. Having said that, following is some information that may help you: First, you should be applying temperature of 50° F (10° C) in daylight hours can be as high as 65° F (18° C) for the metal temperature. Under such conditions, the zinc will not cure properly, and you will get a dry, powdery flm with very little adhesion and a high degree of porosity. the inorganic zinc during nighttime, if at all possible, in order to avoid excessively fast evaporation of the solvent from the applied flm of zinc before it has had time to react properly with both the silicate liquid and the carbon steel substrate. An ambient Notes From the Blog when the going gets tough... we get tougher. Foot traffc, vehicle traffc, heat, cold, the relentless effects of weather... With these kinds of forces stacked against you, it's essential to have a coating that can rise to the challenge - one that you can have confdence in to remain strong and effective no matter how hard you use or abuse it. Wearcoat ® foor coatings defne durability. Easy to apply, easy to clean, non-slip and incredibly tough, Wearcoat ® will give you the edge you need to get the job done - safely and effciently. Call us today or check us out on the web. Our expert staff is ready to help with any coating needs you have... COATINGS FOR INDUSTRY, INC. Call us today – 215-723-0919 Fax 215-723-0911 www.coatingsforindustry.com COAT SG SERIES ANTI-SLIP COATINGS Serving the concrete fooring, structural steel, transportation and aerospace industries for over 35 years. Wr i te in Re ad e r In q u ir y #1

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