Transcript B4 A Corrosion Protection of Pipe Casings

Corrosion Protection
of
Shorted or Contaminated
Pipe Casings
Presented by:
Kelly Baker, Zerust Oil & Gas
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AGENDA
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Introduction
What are VCIs
Pipe Casings
Current Practices
Vapor Corrosion Inhibitors
Questions
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Reducing Corrosion
Corrosion cannot be
eliminated, it’s mechanism
can only be slowed down
Failure prevention provides a
better return on investment
than "failure management"
What are Vapor Corrosion Inhibitors?
A corrosion inhibitor is a substance when added in a small concentration to an
environment reduces the corrosion rate of a metal exposed to that environment.
Contact Corrosion Inhibitors
• The radiator fluid in your car is a good example of inhibitors being used to
provide corrosion protection. In this case the radiator fluid is in direct contact
with the metal surface.
• There is also a special kind of inhibitor called a volatile corrosion inhibitor.
Volatile (or Vapor) Corrosion Inhibitors
• Volatile Corrosion Inhibitors (VCI), are compounds transported in a closed
environment to the site of corrosion by volatilization from a source.
• In their “natural state” (room temperature), the VCI can be a solid, liquid or gas.
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Vapor Pressure
• The pressure exerted by the gas in equilibrium with a solid or liquid in
a closed container at a given temperature is called the vapor
pressure.
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How Do VCIs Work?
Barriers
• Acts as a barrier layer between the metal and the environment.
• Adsorption can be either physical (electrostatic) or chemical
(sharing electrons)
Definition Cont.
VCI molecules fill space and deposit on all
surfaces.
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Can work for immersed surfaces
Not a ‘coating’
Does not change the metallurgy
Not permanent
Can be painted/welded
Non-toxic
Can be designed for the service
Not “NEW” Technology
Environmentally friendly
Requires no cleaning prior to assembly
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VCIs have been sold through
major retailers for years
Several ‘consumer market’ products you can try
• Lowes
• Cabellas
•Flambeau
•Kobalt
•…others
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Cased Crossings
Cased Crossings
Good or Bad?
Comments
Corrpro
• From a corrosion point of view, casings should simply be avoided
Kinder Morgan
• The disadvantages from a pipeline corrosion point of view are many;
– additional design and construction costs
– additional maintenance
– monitoring of electrical isolation
• the problems associated with electrical shorts, including;
– remediation
– additional monitoring
– increased loads on the cathodic protection (CP) systems
Panhandle Energy
• I believe that there are no benefits to cased crossings
Problems
Metallic Shorts
Contaminants
Protection Options
• Cathodic Protection (CP)
• Wax fill
• Vapor Corrosion
Inhibitors (VCI)
NACE - SP200-2014 Steel Cased Pipeline Practices
Appendix “A” – Options for Mitigation of Carrier Pipe Corrosion in the Casing Annulus
• A3.2 Option #1: Inject the casing with Corrosion Inhibiting Gel Filler
• A3.3 Option #2: Apply a Multiphase Vapor Corrosion Inhibitor System
PHMSA – D.1.1.2 (references NACE SP200)
Multi-phase
Dry
Multi-phase
Wet
VCI Gel
Pre-mix
VCI Gel
Gel set-up can plug penetrations
PHMSA
VCI Gel
Gel set-up can be manipulated
VCI Gel
Dual action protection
Results
Placeholder for data
Results
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Diameter of Carrier and Casing pipes?
Length of the Casing?
Is the casing shorted?
Estimated volume of water/solids in the casing?
Has a pressure test of the casing been done? Results?
Vent pipe size and penetration size through the casing?
Vent pipe connection – which one is top and which one is
bottom?
8. Condition of the end seals (if known)
9. Will owner be digging and repair/replace the seals? Age and
type?
10. Elevation difference along the length of the casing?
Summary
1. VCI’s are a cost effective alternative to
traditional corrosion protection methods.
2. VCI’s can be applied to most casings through
the vent pipes.
3. VCI’s are effective at protecting both in contact
areas and the vapor spaces.
4. VCI’s for casing applications are approved by
both NACE and PHMSA.
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Thank you!
Questions?
Kelly Baker
[email protected]
832-465-5668
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