A collection of recently edited and up-dated technical guidance documents from the CED Coatings group has recently been published in the member’s area of the Institute of Corrosion website. Each document includes extensive referencing to relevant standards and other sources of information. A summary of these documents is presented here. Please note that to access the members area you will need to register or re-register by filling in the on-line form at https://www.icorr.org/members-area.
CED/CT01 Inspection and testing – Surface preparation and organic coating-related inspections
This document discusses the purpose of inspection, the specific areas that a paint inspector might check, the relevant standards and methodologies, the reasons behind the various requirements, and the equipment used. Subject areas include: pre-coating (visual inspection, surface profile checks, extraction of soluble salts, surface cleanliness checks, ambient monitoring) and post-coating (coating thickness checks, adhesion testing, holiday detection). The focus is on those methods which are considered the best, or most commonly used, but an emerging test for post-coating corrosion protection monitoring, namely electrochemical noise measurement, is included as an Appendix.
CED/CT02 Surface Preparation Methods
CT2 provides an insight into the types of preparation methods that are available, the equipment used and how this is related to industry standards. The three common surface preparation methods, i.e. abrasive blasting, hand and power tool, and water jetting, are discussed, with particular attention given to water jetting, which is less well-known than the others. The advantages and disadvantages of each method are also highlighted.
This document provides an insight into the available coating application methods and the equipment used. The various application methods described are: brush application, roller application, spray application (including air-, airless-, HPLV-spraying, auto-deposition, and rotating discs and bells), dip coating and flow coating.
CED/CT04 Paint: a definition and generic organic coating types
This document provides an insight into the generic organic coating types that are available, highlighting the types and compositions of the coatings. It begins with a brief definition of what comprises a paint system and an outline of why, when and where anticorrosive paint is used. It provides definitions of resins (e.g. alkyd, epoxy, polyurethane/acrylic urethane, vinyl esters, and silicone-based resin systems), pigments and extenders, solvents, additives (driers, thixotropes, UV absorbers, de-foamers, wetting agents). Some examples of complete paint systems (primer, stripe coat, intermediate coat or coats, and finish coat) are also given.
CT05 defines the technique of thermal metal spraying, placing it in context and noting the relevant surface preparation standards. The methodology is then described in detail, including flame spray and arc spray. Properties such as abrasion resistance, galvanic protection, longevity and the permeability of thermal metal spray to water are discussed. This is followed by a section covering the appropriate uses of TMS, as well as noting where it is NOT recommended.
CED/CT06 On-site and off-site application of intumescent fire and corrosion protection coatings for steel structures
This document provides a definition of intumescent coatings and highlights the key issues concerning specification and use of the types of coating appropriate in particular contexts. It also covers, certification, development and handling of the coating, and preparation of the substrate surface, together with the advantages and disadvantages of off-site or on-site application.
An emphasis on the corrosion protection aspects of the intumescent system, and information on the types of system that will be effective in this context, are included in the sub-section on environment. A large number of sources of further information are included towards the end.