CoatingsPro Magazine Supplements

Equipment 2018

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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30 EQUIPMENT 2018 COATINGSPROMAG.COM By R. Prasanna, Deputy General Manager — QMS at Essar Projects (India), Ltd. Specification and Inspection Play a Vital Role in Coating Steel Structures is article provides some basic concepts for young corrosion engineers to improve skills on coating specification and inspection that will impact structural steel painting work. is brief and simple presentation promotes understanding as a foundation for future development. T he coating specification w ill determine the entire scope of any coating project. Specifically, for a painting project, this is broken dow n into three broad categories: the product to be used, the surface preparation required, and application of the product. The Product "Sole spec" sheets are written specifically for a certain product. is is a situation where "shall " or an equally stern term will be used to refer to the product to be used. In some instances, a few options may be provided, as indicated by the word "may," where a substitute or alternative is acceptable, provided all requirements are satisfied. Surface Preparation e most commonly accepted industry standards pertaining to surface preparation have been devised by several national and international bodies (e.g., NACE International and SSPC: e Society for Protective Coatings). ese standards are used when assessing the readiness of a surface to receive a coat of paint. ese surface preparation standards range from solvent cleaning — SSPC Surface Preparation (SP) 1 — to industrial blast cleaning — NACE No. 8/SSPC-SP-14. e proper anchor pattern is essential for optimal coating adhesion. Each standard defines the method of cleaning as well as criteria for evaluating the outcome. Because surface preparation is such a tremendously important step in the process (an improperly prepared surface is a surefire way to shorten the coating's service life), specification sheets must either stipulate the required level of surface preparation or direct the contractor to a product data sheet that does so. Please note that a product data sheet by itself is not a technical specification. Application Coating application is another section of the specification that should heavily reference specific product data sheets. e ambient conditions, number of coats, and mil thickness required for a successful application should be spelled out in that document. e specification should also identify the method to be used for coating application. If a specific formulation (e.g., a 100 percent solids formulation) is called for, this section should also include any notes on required application equip- ment, such as plural component pumps. e contractor should also be made aware of any other challenges that may arise during the application process in this section of the specification sheet. e paint specification must stipulate which products are required (or product characteristics that must be satis- fied) and how they need to be applied, as well as the surface preparation required for the job. ese are the core elements of a paint specification. Understanding the Basic Concepts of a Painting System e various superimposed coats within a painting system must, of course, be compatible with one another. ey all may be the same generic type or different types (e.g., chemical resistant types, such as a recoatable polyurethane finish coat, may be applied onto epoxy primers and intermediate coats). As a precaution, however, all paints within a system should normally be obtained from the same manufacturer and used in accordance with the manufacturer's recommendations. An important factor in the coating system is the defini- tion and measurement of the dry film thickness (DFT). Generally, DFTs are checked on the completed paint system, although individual films may be checked separately. Usually, nominal DFTs are specified, but sometimes minimum values are quoted. Equipment

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