• Internal pipework coatings used an incorrect specification of coatings materials
• Pipework had multiple areas of corrosion
A narrow single-track road required use of the CSC mobile welfare units. All site inductions, method statements, permits and site briefings from site agent and framework delivery manager were conducted before work commenced.
The internal pipework coatings were found to be out of specification as the previous coatings were not DWI-approved. Many areas of corrosion were identified on the pipes.
The sump was emptied, scaffold erected, the tank dried and made ready for the coating removal.
The old coatings were removed by trained CSC Services operatives, who used calibrated shot blast equipment. The nozzle man and team used the correct grade of blast media to achieve the specified surface profile and cleanliness needed to accommodate the paint specification.
All coatings were removed via shotblast before the our in-house NACE Level 2 coatings inspector tested the cleanliness (SA21/2 ) and surface profile, which was 75 microns in this instance. Climate control equipment was employed to achieve the required temperature and humidity for the coating removal and application.
Pipework coating used was BASF Masterseal M808, a DWI-approved polyurethane coating, applied in 3 coats – a stripe coat to all flanges, nuts and bolts followed by two no. coats applied between 150 – 300 microns per coat. All coatings were applied in accordance with current BASF IFU (Instructions For Use) and safety data sheets. Temperature and humidity monitoring and thickness gauge tests were documented, and time stamped photographs taken for each applied coat.
A final spark test and inspection by our coatings inspector concluded the Quality Assurance information needed for the quality plans, which include all equipment calibration certification, data logger cure information, coating records, coating batch numbers, dates and storage information and temperatures. The pipework coating was cured for 7 days at +20o before the whole tank was cleaned and returned to the client.