COATING APPLICATION "DO'S AND DON'TS"

Do's and Don'ts 

Even the right coatings are often doomed to failure before they are applied.  There are many reasons for this, such as:

• Over reliance on the contractor.  Plants usually do not employ anyone with this specialty expertise and so there is an over-reliance on the contractor for coating material selection and specification writing.  Although many industrial coating contractors are sufficiently  knowledgeable regarding correct surface preparation and coating application, the contractor usually does not have adequate background or knowledge of how the equipment will operate, what the specific jobsite scenario will involve, and the condition of the steel surfaces to receive the coating.
• Lack of information on the equipment condition and anticipated range of operating temperature.  Is the steel surface heavily corroded or pitted?  Will it be in cyclic or intermittent service?  Will it operate below the dewpoint?   
• Lack of information regarding on-site restrictions on methods of surface preparation.  Will dry abrasive blasting be allowed?  What means of protection from grit and dust would allow use of abrasive blasting?  What is the cost of this? 
• Lack of a detailed written coating specification  
• Lack of a pre-job meeting where all parties review the specification and come to agreement on timing, scope, materials, method(s) of surface preparation, method(s) of coating  application, special needs regarding protection from weather, special needs regarding work on vessel or piping while in operation, inspection hold points 
• Lack of third party inspection

All of these details can result in confusion on the contractor's part, improper selection of the coating material, improper surface preparation and coating application, or all of these.  We have found that problems result most often from inadequate flow of information and details.  Plant personnel often do not understand what details are necessary to draft the specification, nor is there typically the correct expertise readily available to gather the information, select the proper coating material and draft the specification

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