Title: Coatings
1Coatings Directional Boring
2Coatings Directional Boring
- Design Considerations (data collection)
- Contributed coating failures
- Pre-Operation steps
- Post-Operation steps
3Design Directional Boring Coatings
- Data Collection for coating selection
- Surrounding Environment
- Soil composite
- Location
- Foreign lines
- Other pipelines
- AC Transmission towers
- Timeframe
4Design Directional Boring Coatings
- Powercrete
- 12 to 15 mils of FBE (Fusion bonded Epoxy) 3M
6233 - Concrete polymer base outer coat 20mils per
application, two applications normally used - Typically 55 to 60 mils coating thickness
- FBE Dual coat
- 12 to 15 mils of 3M 6233
- 20 mils of a Dual coat application of 3M 6352
- Typically 35 mils total coating thickness
5Design Directional Boring Coatings
- Time frame considerations
- Powercrete hand applied, 4 joints per 2 hours
can be coated - FBE Dual coat assembly line, 3000 feet in
three hours
6Design Directional Boring Coatings
- Durability
- Powercrete UV protected, more abrasive
resistance in comparison to the FBE dual coat - Recommended practice
- Abrasive environment use the Powercrete
application, - In well known normal soil application, FBE dual
coat acceptable and probably more cost effective
7Design Directional Boring Coatings
- Coatings Case history - Failures
- The most popular coating failure -
- Cathodic Shielding
- Rock formation
- Pipe wedge next to a rock formation at the point
of coating holiday - Disbondment coating
- Coating becomes disbondment from the surface of
the pipe, but shields the CP from the surface of
the metallic structure exposed under the coating
8Cathodic Shielding - Rock
CP
CP
ROCK
Pipeline
CP
9Cathodic Shielding Coating Disbondment
CP
Pipeline
CP
10Design Directional Boring Coatings
- Coatings Case history - Failures
- Thickness of coating application
- The thicker of the coating, less durable, more
brittle
11Harlem RD Bore Coating Failure
12Design Directional Boring Coatings
- Coatings Case history - Failures
- Powercrete
- Flexibility Degrees per pipe diameter
- 1.4 for 35 mils
- .75 for 55 mils
- FBE Dual Coat
- Flexibility Degrees per pipe diameter
- 2.8 for 35 mils
13Design Directional Boring Coatings
- Coatings Case history Failures
- FBE Dual coat more flexible than Powercrete
- But,,,
- Powercrete more impact resistance than FBE
14 Design Directional Boring Coatings
- Powercrete application adhesive bond to the FBE,
and the dual coat 3M will result of complete pull
out of coating application from the metal surface
due to, coating flexibility angle being too great - In a normal pulling process, coating will be
disbondment by layers and normally does not
result in total removal
15 Design Directional Boring Coatings
- Girth Welds
- Two part Liquid Epoxy used
- Protal 7200 - 50 or greater
- Protal 7125 - 50 or less
- R95 Powercrete J (new)
- Pipe Preparation
- Sand blasting NACE 2 or SSPC-SP10
16Northern Loop Hoover Bore Girth Welds
17Design Directional Boring Coatings
- Transmission Class pipeline
- ECDA
- Pipe thickness design
- SYMS
- ICDA
- Internal Coupons
- Probes
- Inclination angle consideration
- Do not get greater than the Critical Inclination
angle - Inline Inspection smart pigging
18Pre-Operation Steps
- Columbia Gas needs to inspect all coated pipe
line at the coating mill before the pipe is
coated - Corrosion Technicians are being trained, KTA
certified - Communication should be placed to Corrosion FLL
by Supply chain - Need to consider cost of technician or coating
inspector to work order budget
19Corrosion Department InspectingPowercrete
application for Maumee River Crossing
20 Pre-Operation Steps
- Pipe Inspected in the field by the corrosion
department - Determine any coating defects due to shipment
- Pipe and girth welds coatings inspected in the
field by the corrosion technicians - Dew point readings
- Pipe Temperature
- Chloride check
- DFT
- WFT
- Observe Jeeping process recommend voltage
setting
21Post Operation Steps
- Survey Coating and CP
- CP
- CIS Close Interval survey
- External Coupons used
- Coating
- DCVG Direct Current Voltage Gradient
- ACVG PCM Alternate Current Voltage Gradient
- Cost of survey new steel pipe by corrosion
department should be considered on the work order
budget
22Thank You Any Questions??