casing patch customized

Saltel customized patch brought an idle (2 years) well back to previous production rates.

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Published on 19 October 2022

We customized a patch based on the client’s requirements and the well’s condition. For this operation, the client was looking for a mechanical technique that would also provide a gas-tight solution for the well. 

A prolific gas producer in Southeast Asia was shut-in and idle due to a tubing leak resulting in a significant decline in the total hub production. The tubing leakage is due to oxygen corrosion cracking, sulfide stress cracking, or stress corrosion cracking.   

Gas-tight patch for tubing leak repair
Operating platform for tubing leak repair.

Saltel industries is always determined to meet the challenging downhole expectations of the client. Therefore, after the tubing leak detection results and considering all the challenges in this tubing leak scenario, we decided to opt for a customized patch.

Operational PhasechallengeSolution
Leak detectionLeak geometryDiamond shape leak up to 1in (patch supported)  
Patch DeploymentRig availability   
Limited space 
SLB ACTive CT (Coiled Tubing) 
Patch design 150 degC working temperatureNickel-based alloy + Fluoroelastomer skin
High salinity   
CO2 concentration
H2S concentration
Hg concentration 
Nickel based alloy 

We produced a design different from the standard patch, which was the solution for this tubing leak. 

As a result, we selected a nickel alloy as the patch material based on the root cause failure analysis (RCFA) outcome. This alloy can withstand elevated temperatures and pressure. In the same fashion as choosing the patch thickness, we had to keep two things in mind.

  • Obtaining the largest post-setting ID
  • And creating the strongest patch possible.

We further improved the design of the patch meant to isolate the tubing leak, by adding fluoroelastomer to the whole exterior. 

The patch stood up to the client’s expectations, and we derived our results. 

Consequently, the patch successfully brought this well back into production using a fast, cost-effective approach. This approach did not involve any communication between the tubing and the A-annulus. Subsequently, the patch delivered: 

  • A zero tubing leak was noted during the post-setting pressure test (tubing leak test procedure).  
  • The steel grade (nickel alloy) and fluoroelastomer skin helped to withhold the well environment.  
  • The patch was successfully deployed with accurate positioning thanks to the intelligent coiled tubing unit/method the coiled tubing method. 

The custom design gave the patch incredible versatility and fit-for-basin features unseen in the area.

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