Mobilize Shorted Casing Questions Blog

Shorted Pipe Casing? What to know BEFORE you Mobilize.

Shorted Pipe Casing? What to know BEFORE you Mobilize.

Like many of your assets, no two pipe casings are alike. As you evaluate your ILI (In-Line Inspection) reports or CP (Cathodic Protection) data, you may find anomalies that require further inspection of your casings. Often times, information on the casing may be hard to come by or even finding vent pipes can be difficult.

Options for Metallically Shorted or Electrolytically Coupled Casing

There are a few options in the market for how to deal with a metallically shorted or electrolytically coupled casing:

  1. Clear the short
  2. Inject with Vapor Corrosion Inhibitor (VCI),
  3. Fill with a high dielectric fill material.

But before you make that decision, there are some questions that should be answered which can save a lot of time and money later.  Do a pre-job inspection of the casing!

Casing Inspection Questions to Answer Prior to Project

Too often, a project is planned and the contractor gets to site to complete the project and one or more of these questions, not understood before arriving, will delay or possibly eliminate the method planned. On the other hand, if these questions are answered, there will almost never be a situation where the planned application cannot be accomplished.

Once these questions are addressed, a method and materials proposal can be designed to meet the needs of that particular casing. Remember, every casing is different!

Either your team, or a contractor can usually answer the following questions:

  1. General Casing Information
    1. Measured distance between vent pipes
    2. Estimated volume of annular space
    3. Estimated elevation change between ends
  2. Camera Inspection of Vent Pipes
    1. Vent pipe diameter
    2. Casing penetration size at the vent pipe
    3. Wax or other material visible in the casing/vent pipe
  3. Casing Airflow
    1. Does air flow from low side and out the high side vent pipes
    2. Is there any water discharge during this test and if so, how much (Zerust does not propose to push any standing water out of the casing as that should be done just before the VCI injection)
  4. Casing Pressure Test
    1. Does not hold 1 psi
    2. Holds 5 psi for 10 minutes
    3. Holds 5 psi then drops
    4. Is the casing a candidate to fill without excavation
  5. Site Access Information
    1. Road type and speed limit, or waterway/railway details
    2. Side to stage fill equipment
    3. Side to stage discharge
    4. Traffic control required

Need Corrosion Protection for Casings? The Zerust Oil & Gas Team is Here to Help!

Zerust has developed a unique blend of corrosion inhibitors and gels that is injected into the annular pipe casing space. The Zerust corrosion inhibitors protect the carrier pipeline both in direct contact, using Soluble Corrosion Inhibitors and also through Vapor Corrosion Inhibitors that protect the entire annulus vapor space.

Click Here for Protection of Shorted Casings

The staff at Zerust Oil & Gas are here to custom design a corrosion mitigation solution that is specific to your given asset. Contact us today to find out how we can help extend the life of your equipment.

Click Here to Get in Touch

Protection of Shorted Casings

Types of Casing Fillers – Advantages and Disadvantages

Cathodic Protection and VCI Gel Filled Pipe-Casings for Corrosion Protection

How the Zerust Process Works from Start to Finish

Evolution of VCIs in the Oil & Gas Industry Editorial with Business View Magazine

Effectively Combating Corrosion