Technical Specification Document
SPC-ENG-042: Surface Preparation Procedure for Carbon Steel
Field
Value
Document Code
SPC-ENG-042
Revision
1.0
Issue Date
2023-11-10
Prepared by
A. Fernandes
Reviewed by
M. Kouadio
Approved by
L. Yamada
Department
Engineering - Coatings Division
1. Introduction
This specification outlines the technical requirements for surface preparation of carbon
steel substrates prior to protective coating application, applicable to maintenance and
small-scale refurbishment projects under Division 5 contracts.
2. Scope
The procedure applies to all project scopes involving tank internals, piping systems, and
structural components where carbon steel is the base material. Work must comply with ISO
8501-1 and ExxonMobil GP 56-02-02 or GP 56-02-11 depending on the project type.
3. Equipment & Materials
- Abrasive blasting machine (Graco EcoQuip 2 EQs)
- Industrial air compressor (minimum 185 CFM)
- Surface profile gauge (Testex or Elcometer 224)
- Clean air supply and dust extraction system
- Personal Protective Equipment (PPE) as per HSE-PRO-09
4. Surface Preparation Process
4.1 Degreasing shall be done using SSPC-SP1 solvent cleaning methods.
4.2 Substrates must be abrasive blasted to a minimum Sa 2½ finish.
4.3 Surface profile must be within 40–75 µm as measured with replica tape.
4.4 Substrates must be visually clean and free of dust, rust, oil, and mill scale.
5. Environmental Conditions
- Relative humidity: Must be below 85%
- Steel temperature: Must be at least 3°C above dew point
- Ambient conditions must be monitored continuously using calibrated instruments
6. Inspection & Hold Points
- Surface cleanliness to be verified by Level II Coating Inspector
- Hold Point: Blasting completion prior to coating application
- All inspection records must be logged under form QC-09-SPC
7. Safety Considerations
- Use of certified PPE is mandatory
- Work in confined spaces requires a permit and atmospheric testing
- Follow safe blasting procedures in accordance with HSE-GDL-13
8. References
- ISO 8501-1: Visual Standards for Surface Cleanliness
- SSPC-SP1: Solvent Cleaning
- ISO 8503-5: Surface Roughness Measurement
- GP 56-02-02: Painting for New Construction (ExxonMobil)
- GP 56-02-11: Coatings for Maintenance and Other Small Projects (ExxonMobil)