Monday, October 4, 2010

Blasting and Painting Procedure

1.0 Scope
1.1 This construction procedure covers the control of materials and the procedure to be followed in the course of surface preparation, painting/coating application, inspection and safety requirements for aboveground piping for Field Surface Facilities Project of Melut Basin Oil Development Project, Sudan. Detailed specifications and/or equipment shop drawings shall be used in conjunction with this procedure.

2.0 Reference Documents
2.1 Owner’s specification
PDOC-SP-MEC-013 Specification for External Painting & Protective Coatings
PDOC-SP-MEC-032 Specifications for Internal Coating, Tanks, Vessels, Piping
PDOC-SP-CIV-019 Specification for External Painting and Protective Coating For Structural Steel
PDOC-SP-PPL-004 Specification for Fusion Bond External Epoxy Coating for Steel Pipe
2.2 SSPC Steel Structure Painting Council Standard,
SSPC-SP1 Solvent Cleaning
SSPC-SP2 Hand tool Cleaning
SSPC-SP3 Power Tool Cleaning
SSPC-SP5 White Metal Blast Cleaning
SSPC-SP7 Brush Off Blast Cleaning
SSPC-SP10 Near White Blast Cleaning
SSPC-PA1 Shop, Field, and Maintenance Painting
SSPC-PA Guide 3 A Guide to Safety in Paint Application
SSPC-PA2 Measurement of Dry Paint Thickness with Magnetic Gauges

3.0 Material Control
3.1 All materials send to the job site should be inspected in accordance with the procedure for material’s loading, unloading, storage and distribution. In addition, coating material shelf life shall be checked for expiry date.
3.2 All coating materials shall be delivered to the job site in original unopened containers with labels intact.
3.3 Each container of paint shall be clearly marked or labeled to show paint identification, date of manufacture, batch number, analysis of contents, identification of all toxic substances, and special instructions
3.4 Coating material shall be stored in a location that is protected from the elements, well ventilated and free from excessive heat, open flame, or other sources of ignition in accordance with the manufacturer recommendation and CONTRACTORS procedure.
3.5 Type of blasting abrasive shall be approved by OWNER.
3.6. Sand blasting abrasive cleaning shall be used by the CONTRACTORS which by any means must abide to the OWNERS Specifications.
3.7 Sandblast sand shall be fresh water washed, controlled particle size, high silica content sand, with sharp angular surfaces and no soft particles to ensure fast, positive cleaning action with a minimum of dusting when used to blast clean metal surfaces. Under no circumstances shall it contain clay particles or any other extraneous matter.

4.0 Inspection Equipment
4.1 The following inspection equipment shall be kept available during blasting and painting operations:
a) A temperature gauge and a hygrometer
b) Surface profile gauge
c) Wet film thickness gauge
d) Dry film thickness gauge (for DFT measuring25 µm to 5 mm)
e) Holiday detector
NOTE: Surface profile Gauge & Dry film Thickness must be able to gauge flat and round surfaces.

5.0 Blasting And Coating Equipment
5.1 The type of surface preparation by power tools or painting blasting and coating equipment shall be as per specification, coating material manufacturer’s recommendation and as approved by OWNER including as follows:
5.1.1 Power tool cleaning equipment
5.1.2 Dry abrasive blasting equipment
5.1.3 Air spray equipment
5.1.4 Airless spray equipment ( if necessary )
5.1.5 Brushes
5.1.6 High density battery powered light for internal coating
5.1.7 Ventilation equipment
5.2 All the equipment shall be ready and checked as being in good within working order prior to and during blasting and coating operations and shall be kept in a sufficiently clean condition to avoid surface and/or coating contamination.

6.0 General
6.1 Work shall be done by qualified personnel in a neat and workmanlike manner conforming to all applicable OWNER specification. CONTRACTORS to carry out any type of surface preparation and painting or coating qualification prior proceeding with actual work.
6.2 All coating shall be done in accordance with manufacture’s recommendations. Where specifications contained herein conflict with manufacturer’s recommendations the conflict shall be referred to OWNER for written clarification prior to the commencement of work.
6.3 The numbers of coating and the thickness of coating should be in accordance with approved IFC drawing or Owner’s specification listed in chapter 2.

7.0 Atmospheric Conditions
7.1 The applicator shall measure the ambient conditions at regular intervals prior to and during of any type of power tooling or blasting painting/coating, and keep records of prevailing temperature, humidity and dew point.
7.2 No surface preparation or application of material may take place when steel surface temperatures are less than 3c above the dew point or above 50c at the time of coating.

8.0 Surface Preparation
Surface preparation shall be in accordance with paint manufacturer’s instruction and project specification, whether blast cleaning, power tool, hand tool or solvent cleaning.
8.1 General
8.1.1 Surface preparation shall be done in accordance with Steel Structures Painting Council surface preparation specifications defined in Steel Structures Painting Manual Volume 2.
8.1.2 The blast cleaning abrasive (sand) shall be determined by the test methods in SSPC-AB 1 (Mineral and Slag Abrasives) specification in order to comply with the SSPC-10 standard. Only abrasive approved by the OWNER will be acceptable for use as a blast medium.
8.1.3 The abrasive shall be dry and free from oil, grease, dust and other impurities. Re-usable abrasive shall be clean and reasonably sharp, contain no rust or noticeably worn abrasives.
8.1.4 Alternative surface preparation methods may be approved when dry blast cleaning is unsafe or impractical.
8.1.5 Blast cleaning shall not be permitted where adjacent areas or equipment are not sufficiently protected from contamination by abrasive dust or debris.
8.1.6 Blast cleaning shall not be permitted in areas close to painting operation to prevent contamination of wet paint film by dust and grit
8.1.7 All organic substance such as oil, grease, and other contaminants shall be removed in accordance with per specification prior to blasting operations.
8.1.8 All rough welds, burrs and sharp surface projections shall be ground smooth and all weld spatter shall be removed prior to blasting operations.
8.1.9 The compressed air supply used for surface preparation must be of sufficient pressure and volume to prepare the surface to the degree specified and shall be free of oil and water.
8.1.10 During blasting, the rise face flanges must be protected at all time. This should be done by covering the rise surface with a round plate that covers exactly the rise surface diameter.
8.2 Near-white Metal Blast Cleaning
8.2.1 Near- white metal blast cleaning shall be in accordance with SSPC-SP10 “Near white metal blast cleaning” (ISO 8501-1 Sa2.5).
8.2.2 SSPC-SP10 “Near white metal blast cleaning” shall be used for the surface preparation of external and internal coating for atmospheric protection of above ground steel structures, tanks vessels, piping systems, and pipelines.
8.3 Power-tool Cleaning
Power-tool cleaning shall be to a visual standard in accordance with ISO 8501-1 St3. Power-tool cleaning shall be done using abrasive or wire-type power discs. Power-tool cleaning shall extend a minimum of 25mm distance into adjoining coated surfaces.
8.4 Hand-tool Cleaning
Hand-tool cleaning is the least effective of the surface preparation methods, but it may be used for touch-up/repair maintenance with certain surface-tolerance coating systems. Hand-tool cleaning shall be a visual standard in accordance with ISO 8501-1 St 2. Cleaning shall be done with brushes, scrapers, sanders or other hand impact tools.
8.5 Solvent Cleaning
Solvent cleaning shall be done in accordance with SSPC-SP1 “Solvent Cleaning’ on the surface examined for the presence of oil or grease.

9.0 Mixing and Thinning
9.1 Paint shall be mixed in accordance with manufacturer’s instruction and as per specification
9.2 Mixing method shall be applied in accordance with the paint manufacturer recommendation.
9.3 All pigmented paint shall be strained after mixing except where application equipment is provided with strainers. Strainers shall be of a type to remove only skins and undesirable matter but not to remove the pigment.
9.4 Where a skin has formed in the container, the skin shall be cut loose from the sides of the container, removed and discarded. If the volume of such skin is more than 2% of the remaining paint, the paint shall not be used.
9.5 Mixing in open containers shall be done in a well ventilated area away from sparks or flames.
9.6 Paint shall not remain in spray pots, painter buckets, etc., overnight, but shall be stored in a covered container and re-mixed before use.

10.0 Painting/Coating Application
10.1 General
10.1.1 Painting/coating shall be applied in accordance with the paint manufacturer’s instructions and this procedure. Whether air spray, airless spray or brush.
10.1.2 Field painting on steel surfaces. Surface preparation shall be finished in accordance with this procedure Section 8.0 before application of primer.
10.1.3 Field painting on shop coating. Any previously applied shop coating must be dry and free of dirt, oil, and other contaminants.
10.1.4 Shop coated steel members shall preferably be field painted after erection of such members is completed. Steel members may be field painted on the ground before erection, provided such painting is touched-up where damaged, with the same number of coats and types of paints after erection. The top coat shall be applied after erection.
10.1.5 When the type of paint for field coating is not specified, it shall be approved and verified whether the paint to be used is compatible with the shop applied coat(s).
10.1.6 Surfaces (other than contact surfaces) of fabricated assemblies which are accessible before erection but which will not be accessible after erection shall receive all field coats of paint before erection.
10.1.7 All field welds and all areas within four inches of welds shall be cleaned before painting, using surface preparation methods at least as effective as those specified for the structure itself; all welds shall either be blast cleaned, or thoroughly power brushed.
10.2 Spray Application
10.2. 1 All spray application of paint whether air, or airless spray, shall be in accordance with the following:
10.2. 2 The equipment used shall be suitable for the intended purpose, shall be capable of properly atomizing the paint to applied, and shall be equipped with suitable pressure regulators and gauges. The equipment shall be maintained in proper working condition at all times.
10.2. 3 Paint ingredients shall be kept uniformly mixed in the spray pots or containers during paint application either by continuous mechanical agitation or by intermittent agitation as frequently as is required.
10.2. 4 Paint shall be applied in a uniform layer with a 50% overlap at the edges of the spray pattern, and 20 to 25 cm away from the surface.
10.2. 5 Brush or daubers shall be painted for cracks, crevices, blind areas of all rivets and bolts, and all other inaccessible areas.
10.2. 6 Paint manufacturer’s instructions regarding pot life, drying/curing intervals between successive coats and final curing periods before assembly or transport, shall be followed.
10.2. 7 Each layer of paint shall be allowed to dry for a period of time within the limits prescribed by the paint manufacturer, before the next layer is applied.
10.2. 8 No coating shall be applied to edges prepared for field welds or within 50mm of these edges, except for a prefabrication or welding (shop) primer which shall be limited to a maximum 25 microns.
10.3 Airless Spray Application
10.3. 1 Airless or high pressure spray application of paint shall be in accordance with all of the provision of Section 10.2.1 And in addition shall comply with following:
10.3. 2 The air pressure to the paint pump shall be adjusted so that the paint pressure to the gun is proper for optimum spraying effectiveness in accordance with paint manufacture’s recommendation.
10.3. 3 The trigger of the gun should be pulled fully open during all spraying to insure proper application of paint.
10.3. 4 Airless paint spray equipment shall always be provided with an electric ground wire in the high pressure line between the gun and the pumping equipment. Further, the pumping equipment shall be suitably grounded to avoid the build-up of any electrostatic charge on the gun. The manufacturer's instruction should to be followed regarding the proper use of the equipment.
10.4 Brush Application
10.4. 1 Brush application shall be done in areas which cannot be properly sprayed and for touch up maintenance where spray application is not practical.
10.4. 2 Brush shall be of a type and size which permits proper application of paint. Round or oval brushes are most suitable for irregular surfaces such as bolts, weld, pitted steel, etc. Wide flat brushes shall be used for large flat areas.
10.4. 3 Paint shall be worked into all corners and crevices.
10.4. 4 Rugs and sags or other defects will not be permitted

10.5 Critical Internal Coating
10.5. 1 For critical internal coating of tanks /and vessels, all crew supervisors, abrasive blasters and paint coating applicators shall be fully conversant with all aspects of the blasting and coating operations. All equipment i.e. lights, air extractor’s to conform to safety requirements.
10.5. 2 The method of application used shall be governed by the coating manufacturer’s recommendation for the particular coating being applied. Method of application shall also be considered by the immediate vicinity where work will be carried out.
10.5. 3 Warning notes shall be clearly paint specified on the external surface of all internally coated vessels: “INTERNALLY COATED – DO NOT WELD – HANDLE WITH CARE”.
10.6 Detailed Painting System
10.6.1 The detailed painting system shall conform to the Owner approved IFC drawings and Painting Manual which CONTRACTORS should submitted prior proceeding the works.
10.7 Check list Details
10.7.1 For the check list details refer to Blasting Painting/coating Inspection and Test Plan.

11.0 Drying/Curing
11.1 All drying and re-coat times shall be that specified by manufacturer.
11.2 Curing shall conform to the manufacturer’s recommendations. Force curing shall only be done in accordance with manufacturer’s recommendations.
11.3 Paint shall be protected from rain, condensation, contamination until dry to fullest extent practical.
11.4 No paint shall be subjected to immersion before it is thoroughly dried or cured.

12.0 Inspection and Testing
12.1 General
It shall be the responsibility of contractor to conduct the test and inspection as follows in accordance with paint manufacturer’s application instruction and project specification. OWNER shall monitor all tests performed by Contractor.
The following tests shall be performed at start-up and at specified intervals.
12.2 Environment Check
12.2.1 Before commencing work on surface preparation and coating, the atmospheric temperature and relative humidity shall be measured in order to determine the dew point. Relative humidity readings shall be measured a maximum interval of 2-hour.
12.2.2 Following determination of the dew point, the steel surface temperature shall be measured at regular 2-hour intervals. The steel surface temperature shall be 3ºC or more above the dew point during surface preparation as well as during coating.
12.3 Visual finished coating
12.3.1 The finished coating surfaces shall be of uniform color and free from pinholes, peeling, sags, and runs. etc.
12.4 Film Thickness Measurement
12.4.1 The dry film thickness of individual coats and of the total coating system shall be checked at 5 random locations over areas representative of the work in progress. There shall be a check of at least one area on each horizontal, vertical and curved surface. For internal coating of tanks and vessels, a minimum of 10 random areas shall be checked.
12.4.2 With the exception of areas such as welds, crevices, etc. the specified minimum dry film thickness shall not be exceeded by more than 50%.
12.4.3 Dry film thickness shall be measured with a coating thickness gauge suitable for given type of coating thickness range and substrate material (magnetic or nonmagnetic).
12.4.4 CONTRACTORS shall insure that all the inspection, measuring and test equipment has a valid calibration certificates.

13.0 Repair Of Damaged Areas
13.1 Damaged painting and coating, and/or coating which does not pass the holiday detection test shall be repaired and retested to the satisfaction of OWNER
13.2 The coating materials used for repair and maintenance shall be the same as the original materials
13.3 The surface preparation method for repair will depend upon the size of areas to be coated and the repair coating materials required.
13.4 The area of the coating damage or holiday, along with the adjacent area of coating for a minimum of 25 mm on all sides shall be thoroughly prepared /abraded.
13.5 The painting repair method shall be as per paint manufacture’s specifications.
13.6 Repair coating shall be applied so that the final coat overlaps the surrounding sound coating for a minimum 25 mm.

14.0 Safety
14.1 Safety in blasting and painting operations are paramount. Both operators and supervisors must be fully conversant with all safety requirements associated with blasting and cleaning, scaffolding and access platforms, ventilation in enclosed areas, as per project safety manual.
14.2 All spraying equipment shall be earthed, all high lines checked daily, operators shall wear all approved safety equipment at all times when spraying operations are in progress, and warning signs erected when blasting work is in progress.
14.3 Protection of working area environment please refer to HSE plan.
15.0 Quality Record and Inspection Report
15.1 Daily reports shall be assured on all painting activities and recorded on blasting / painting inspection reports. These records shall be maintained and monitored by QC engineer who together with OWNER shall sign on all inspection reports which are included in the inspection and test procedures.

16.0 Revision Note
16.1 This procedure shall be revised if it is found to be inadequate for purposed work upon completion of engineering/new construction practice/new site information or as requested by OWNER.

7 comments:

  1. PDOC-SP-MEC-013 IS A INTERNATIONAL STANDARD

    ReplyDelete
  2. gud post..it helps me..in safety..

    ReplyDelete
  3. am a spray painter 4rm nigeria 8years exprience in blasting n painter,if u r looking blaster n spray painting job just Email me on CHINEDUROYAL@YAHOO.COM

    ReplyDelete
  4. I need job of sandblaster and painter

    ReplyDelete