1. Scope:
This procedure describes the surface preparation & painting work requirements of Vessels manufactured by Engineering Company for buildings, plants and refineries.
2. Referenced Documents:
> SAES-H-001 Coating Selection & Application Requirements for Industrial Plants & Equipment .
> SAES-H-101V Approved Saudi Aramco Data Sheets-Paints and Coatings
> Supplementary Specification For External Coating (From Client)
> Painting Instructions to Vendors for Pressure Vessels/Heat Exchangers (From Client or EPC)
> Approved General Arrangement Drawings.
3. Responsibility:
Production Engineer/Painting Supervisor or his designee shall be responsible for surface preparation & paint application work of vessels . QC Painting inspector shall monitor and verify the surface preparation and painting work as per approved procedure .
4. SURFACE PREPARATION AND PAINTING PROCEDURE GENERAL:
Different brands or types of paints shall not be int er – mixed. Before starting any painting work, ensure that all the surface is free from oil, grease and other contaminants . Prior to blasting and painting operations protective devices such as clothes, screens, movable walls / partitions shall be provided to cover the surfaces & parts not requiring painting & those parts which would be subjected to damage ca used by abrasives during blast cleaning. Particular attention shall be given to protect the flange gasket seating faces for eventual damage during blasting. Care should be ta ken to avoid interference with the execution of other works.
5. Fabrication/Surface Preparation Requirements for Internal Protective Coating:
5.1 All surfaces shall have a smooth contour, free from discontinuities, crevices and sharp projections . All internals shall be fully welded and sharp projections shall be rounded to a minimum radius of 3 mm.
5.2 All welds on surfaces to be coated shall be continuous with a smooth transition from the weld metal to the base material and shall be completely free from surface or surface breaking flaws.
5.3 All surface irregularities, spatter and weld flaws shall be remedied by grinding.
5.4 The amount of grinding performed shall be judicious and performed only to the extent necessary to prepare the weld surface and surrounding metal surfaces. Over- grinding, which would result in decreasing the wall thickness shall be avoided.
5.5 All welds and welded attachments shall be completed prior to commencing coating activities. All pressure testing shall be completed and accepted before surface preparation and coating activities commence.
5.6 Details for internal coating are provided in V- 2151-301-A-703 Surface Preparation and Internal Coating Procedure .
6. Surface Preparation:
6.1 Abrasive material shall be kept dry and clean and coating inspector shall
decide if substrate requires solvent or detergent cleaning. Weld spatter & sharp edges shall be removed by grinding.
6.2 The surfaces to be painted or coated shall be completely free from dirt, dust, grease, oil & other foreign matter. if present shall be remove d by means of suitable solvent , degreaser or water washing. Do not use kerosene, diesel or other degreaser that ma y leave an oil y film. Excessive layers of rust shall be removed by chipping.
6.3 The compressed air suppl y used for blast cleaning shall be free from water, moisture, oil & other contaminations. The air compressor used for blasting shall be provided with adequate separators & traps . QC painting inspector Shall check and approve the air quality at the start and mid – point of each 8 -hour intervals by bl otter test method .
6.4 The compressor shall be kept running at least 5 minutes & then the pressure shall be set @ 50 psig & blotter or absorbent paper shall be hold at a distance approximately 45 ∼ 60 cm in front of the blast nozzle during air flow. Satisfactory result shall be no water or oil contamination visible on the blotter paper. Garnets used for blasting shall be free from oil , grease, moisture etc.
6.5 Meteorological conditions shall be monitored, verified, record ed and blasting operation shall not be performed under the following conditions:
� When metal surface temperature is less than 3°C above the dew point temperature of the surrounding air.
� When the relative humidity of the surrounding air is greater than 85%
� When the surface temperature is greater than 50 °C as specified in paint manufacturer data sheet.
� When the air temperature is less than 10 °C.
� When there is likelihood of an unfavourable change in weather Conditions after blasting/painting.
� When the available light is less than 500 lux.
6.6 Blast cleaned surfaces shall be checked for anchor pattern by using press-o-film for traceability and permanent record. The degree of cleaning shall be in accordance with the applicable paint specification. Surface found unacceptable or unsuitable shall be reblasted and reinspected again.
7. Paint application:
7.1 Coating materials shall be kept and stored in protected well – ventilated environmental conditions at storage temperature recommended by the paint manufacturer’s data sheets. Temperature sensitive and self polymerization paints must be stored in air conditioned or as per manufacturer’s data sheet.
7.2 All coatings shall be thoroughly mixed and thinned until it is homo genous or in accordance with paint manufacturer’s instructions/technical data sheets just prior to coating application. The quantities over 5 Litre, a power stirrer shall be used.
7.3 For optimum performance surfaces to be painted shall be completely dry and free from burr, flux, scale, rust, weld spatters and all other contaminants which will be ca used for premature paint coating failure.
7.4 Paint shall not be applied when there is a deposition of moisture in the form of rain, condensation, frost etc on the surface.
7.5 After blasting, dust & abrasive particles shall be thoroughly removed from surfaces by vacuum cleaning or blowing with clean dry air before application of paint coating. All blast cleaned surfaces shall be
immediately coated with the specified primer bu t not later than (4) hours after blasting to avoid any corrosion forma ti on or recontamination occurs.
7.6 Paint shall not be applied under the following conditions:
When metal surface temperature less than 10° C or above 50°C or as per recommended Saudi Aramco data sheet.
� When surface contains oil, grease, dirt, rust or other contaminants.
� When the metal surface temperature is less than 3°C above the dew point temperature of the surrounding air.
� During strong wind to bl ow sand, salt spray or to ca use dry spray and disturb the spray pattern.
� During rain or wind y conditions unless operations are performed under suitable cover to protect from weather conditions.
7.7 In Multicoat applications, primer, intermediate and top coats shall be of contrasting colors. If more than 1 application is required to achieve required thickness of particular coat (primer, intermediate, final) then these may be of same colour.
7.8 All welding areas, nuts , bolts and difficult areas shall be brush applied stripe coated to minimize the missing areas. Dry film thickness shall be within the minimum and maximum range and measured with Microtest magnetic gauge.
7.9 Each coat shall be applied uniformally over the entire surface . Top coat shall be free from application defects such as runs, sags, drips, dry spray or foreign matter and uniform in appearance . Paint which have gelled or skinned shall not be accepted and Skips, runs, etc. shall be avoided. When these occur, the y shall be brushed out and surface shall be recoated.
8. Inspection:
8.1 QC Inspector shall monitor blasting & coating to ensure they are performed according to this procedure . Other quality checks viz., Blasting & Painting equipments inspecti on, Calibration, lnprocess inspection etc. shall be done as per above Refrenced Standards.
8.2 The dry bulb temperature & wet bulb temperature shall be taken by whiriling hygrometer/pscychometer. Meteorological conditions, like dew point, metal temperature, humidity shall be measure and recorded at start of each shift and on four hour intervals during surface preparation, painting and curing operations.
8.3 The surface shall be allowed to dry thoroughly prior to applying the top coat. To aid in avoiding pinholes & bubbles occurring in the intermediate coat of epoxy, a mist – coat thinned 10 to 20% should first be applied to the inorganic zinc primer.
8.4 Dry film thickness of each coat shall be measured and recorded using Microtest magnetic gauge. At least five spot readings shall be taken for every 10 sq .meter of paint ed surface area. On each spot an average of 3 readings shall be ta ken. On surface area less than 10 sq. meter at least 5 spot readings shall be ta ken. All the gauges used for measurements and meteorological data shall be duly calibrated.
9. Repair & Touch Ups:
All damaged areas, due to handling etc. shall be repaired as per the paint manufacturer’s recommendations provided in paint data sheets & surface preparation and application requirements in the relevant AP CSs. The required surface preparation, as per paint data sheet, shall be done before any touch -up/repair painting.
10. Documentation:
After completion of blasting and painting, final report attachment E shall be prepared by QC Painting Inspector, verified by QC Engineer and presented to the client inspector for review and sign.
11. Attachments:
Attachment – A Paint System Tables
Attachment – B Quality Control Equipment Check Sheet
Attachment – C In-Process Inspection Sheet
Attachment – D Paints/Coatings & Equipment Log
Attachment – E Blasting & Painting Inspection Report Format
Attachment – F 175-091 900
Attachment – G Approved Coating Material List (Table-B)
Attachment – H Painting Instructions to Vendors for Pressure Vessels / Heat Exchangers
NOTES:
- Saudi Aramco approved paint manufacturer and paint products shall be used. Coating materials which have be en approved shall be select ed from paint suppliers as listed in Table B.
- Repair/Touch up shall be as per paint data sheets or manufacturer’s recommendations.
- Acceptance range of dry film thickness (DFT) check shall be in accordance with SSPC-PA2
- All paints used on one item shall be from the same manufacturer. Substitution or intermixing of coating products from different manufacturers is not permitted.
- Personnel protection shall be considered as insulated surface .
- The bottom of the base plate of equipment supports shall be painted as per APCS-1B
- Bolts & nuts for insulation support shall be coated with the same paint system as attached parts. Bolts & nuts for insulation support on shell shall be painted with the paint system on shell.
- Flange surfaces (excluding gasket contact surfaces) and bolt holes shall be coated.
- Name plates and machined surfaces shall be masked off for protection from coating. Back side of name pl ate bracket including shell surface also shall be completely painted. ODE to provide enough space or access to back side of name pl ate bracket.
- Vendor’s standard color is allowed for internal coating system, unless otherwise specified.
- Applicable paint systems and paint products are highlighted in the table and table is revised in accordance with S-OOO-13A0-001.
- Data sheets of applicable paint products will be shown to assigned inspector at the time of inspection.
Here is one example of paint system table.
NOTES:
1. APCS 1A with final color Aluminum RAL 9006 shall be applied for surfaces without insulation and without fire proofing.
2. If the vessel is insulated, yellow paint shall be applied to the surface outside of insulation.
3. The bottom of the base plate of equipment support shall be painted as per APCS-1B.
4. Yellow paint shall be applied to lifting devices, and maximum lifted weight shall be indicated on each lifting devices.
5. This is Inorganic Zinc coating system and final color not availabe in Aluminum RAL 9006 with paint manufacturer.