Coatings – Directional Boring Tim Jenkins

Coatings – Directional Boring Design Considerations (data collection) Design Considerations (data collection)  Contributed coating failures Pre-Operation steps Pre-Operation steps Post-Operation steps Post-Operation steps

Design – Directional Boring Coatings Data Collection for coating selection Data Collection for coating selection  Surrounding Environment  Soil composite  Location  Foreign lines – Other pipelinesOther pipelines AC Transmission towersAC Transmission towers  Timeframe

Powercrete – 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 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 Design – Directional Boring Coatings

Time frame considerations – Time frame considerations – Powercrete – hand applied, 4 joints per 2 hours can be coated Powercrete – hand applied, 4 joints per 2 hours can be coated FBE – Dual coat – assembly line, 3000 feet in three hours FBE – Dual coat – assembly line, 3000 feet in three hours Design – Directional Boring Coatings

Durability – Durability – Powercrete – UV protected, more abrasive resistance in comparison to the FBE dual coat Powercrete – UV protected, more abrasive resistance in comparison to the FBE dual coat Recommended practice – Recommended practice –  Abrasive environment use the Powercrete application,  In well known normal soil application, FBE dual coat acceptable and probably more cost effective Design – Directional Boring Coatings

Coatings Case history - Failures Coatings Case history - Failures The most popular coating failure - The most popular coating failure -  Cathodic Shielding  Rock formation Pipe wedge next to a rock formation at the point of coating holidayPipe 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 coatingCoating becomes disbondment from the surface of the pipe, but shields the CP from the surface of the metallic structure exposed under the coating Design – Directional Boring Coatings

Cathodic Shielding - Rock

Cathodic Shielding – Coating Disbondment

Coatings Case history - Failures Coatings Case history - Failures Thickness of coating application – Thickness of coating application –  The thicker of the coating, less durable, more brittle Design – Directional Boring Coatings

Harlem RD Bore – Coating Failure

Coatings Case history - Failures Coatings Case history - Failures Powercrete – Powercrete –  Flexibility – Degrees per pipe diameter  1.4° for 35 mils .75° for 55 mils FBE – Dual Coat – FBE – Dual Coat –  Flexibility – Degrees per pipe diameter  2.8° for 35 mils Design – Directional Boring Coatings

Coatings Case history – Failures Coatings Case history – Failures FBE Dual coat more flexible than Powercrete FBE Dual coat more flexible than PowercreteBut,,, Powercrete more impact resistance than FBE Powercrete more impact resistance than FBE 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 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 In a normal pulling process, coating will be disbondment by layers and normally does not result in total removal Design – Directional Boring Coatings

Girth Welds – Girth Welds –  Two part Liquid Epoxy used  Protal ° or greater  Protal ° or less  R95 – Powercrete J (new)  Pipe Preparation –  Sand blasting – NACE 2 or SSPC-SP10 Design – Directional Boring Coatings

Northern Loop – Hoover Bore Girth Welds

Transmission Class pipeline Transmission Class pipeline ECDA ECDA  Pipe thickness design  %SYMS ICDA ICDA  Internal Coupons  Probes  Inclination angle consideration  Do not get greater than the Critical Inclination angle  Inline Inspection – smart pigging Design – Directional Boring Coatings

Pre-Operation Steps Columbia Gas needs to inspect all coated pipe line at the coating mill before the pipe is coated 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 Corrosion Technicians are being trained, KTA certified Communication should be placed to Corrosion FLL by Supply chain Communication should be placed to Corrosion FLL by Supply chain Need to consider cost of technician or coating inspector to work order budget Need to consider cost of technician or coating inspector to work order budget

Corrosion Department Inspecting Powercrete application for Maumee River Crossing

Pipe Inspected in the field by the corrosion department 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 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 Pre-Operation Steps

Post Operation Steps Survey – Coating and CP 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