DHSV locked open to restore access

1920X1080 JANG225682 – Well Stroker (218) – Offshore – Platform, Angola

Well type

Oil producer

Deviation

Vertical at DHSV depth

Max temperature

131 °F / 55 °C

Max pressure

200 psi.

Background

An International Oil Company (IOC) operating in Angola faced a critical challenge with a leaking Downhole Safety Valve (DHSV) that could not be opened from the surface.  Traditional solutions like a slickline intervention were unsuitable due to potential subsequent inner diameter (ID) restriction, which would limit further operations.

The well, a vertical oil producer, operated under challenging conditions with a pressure of 200 psi and a temperature of 131°F (55°C). 

A solution was urgently needed to restore well access and resume production.

Operation

Welltec was tasked with deploying a tailored intervention within a 20-day period. 

Utilizing advanced tools, the operation began with the Well Miller®, equipped with a custom brush, to clear significant corrosion blocking the valve. 

A Well Key® Dimple Tool was subsequently deployed to precisely deform the DHSV’s flow tube, in effect locking it open. 

The process concluded with the Well Key® Friction Grip and Well Stroker®, which engaged and shifted the deformed flow tube to secure the open position.

Furthermore, the Well Tractor®, Welltec Swivel®, Release Device, and Casing Collar Locator, ensured precise, effective intervention.  Surface Read Out (SRO) data facilitated precise monitoring and control of the downhole sequence, optimizing the capture of debris and the operation’s overall success.

Achievements

The intervention restored full well access, enabling the IOC to perform the mud kill displacement, clean out the well, and resume production. 

By avoiding any internal diameter restrictions, future interventions remain unhindered.  The innovative use of Welltec’s tools demonstrated exceptional engineering adaptability, saving time and costs while ensuring operational safety. 

II

The design and deployment of the successful run with Welltec’s Dimple Tool & Key eliminated dependence on TRSV-specific lock open tools.

Client feedback

Products applied

Welltec Tractor hero

Well Tractor®

The original tractor with 30 years of experience

Well Stroker

Well Stroker®

For actuation

- Well Key Dimple Tool hero

Well Key®

Dimple Tool

- Well Key Friction Grip hero

Well Key® Friction Grip

For shifting sleeves without profiles

Welltec Swivel hero

Welltec® Swivel

Mitigate the torque

Welltec Release Device (WRD) Hero

WRD®

Welltec® Release Device

Casing Collar Locator (CCL)  hero

Casing Collar Locator (CCL)

For depth correlation

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