CHDT

Cased hole dynamics tester

Casing is no barrier to accessing your reservoir

The CHDT cased hole dynamics tester conducts multiple pressure measurements and collects fluid samples behind the casing in a well.

In a single trip, the CHDT tester

drills through a casing and into the formation
performs multiple pressure measurements
recovers fluid samples
effectively plugs the hole made in the casing to restore pressure integrity.

In a single run, the CHDT tester can drill up to six holes (one per station) and at each station perform multiple pressure tests and acquire multiple high-quality fluid samples.

350-degF temperature rating

20,000-psi pressure rating

Pressure integrity fully restored during single-trip formation testing

The CHDT tester seals against the casing and uses a flexible drill shaft to penetrate through the casing and into the formation.

Explosives use eliminated to avoid casing damage and compromised measurements

Unlike conventional cased hole formation testers, the CHDT tester does not use explosive charges to penetrate the casing and cement to establish communication with the formation.

Instead, the tester seals against the casing and applies a flexible drill shaft, with built-in instrumentation simultaneously monitoring pressure, fluid resistivity, and drilling position and parameters for real-time quality control of the operation. Drilling can reach beyond the invaded zone, into the formation to access virgin formation fluid.

By drilling instead of using explosives, you won’t apply explosive shock and create casing burrs that can compromise the seal between the tester and casing for obtaining valid pressure measurements or extracting fluid. Explosives also damage the well and formation and cannot provide control of the penetration depth.

Complete resealing of casing holes

The CHDT tester installs a corrosion-resistant plug following testing and sampling to seal the hole in the casing. The mechanical metal-to-metal seal is rated to a differential pressure of 10,000 psi to eliminate the need for remedial casing repair or a cement squeeze.

Interpretation

The CHDT cased hole dynamics tester conducts multiple pressure measurements and collects fluid samples behind the casing, including effectively plugging the hole drilled in the casing to restore pressure integrity. Our reservoir evaluation experts meet with you to design the tester configuration and specify test procedures for determining productivity and permeability along with fluid extraction and sampling. We monitor in situ pressure and fluid measurements in real time to ensure that the job objectives are met. Our multidisciplinary interpretation experts then work with you as needed to leverage this data with advanced workflows and access to proprietary software, including the Techlog wellbore software platform.

Because the CHDT tester efficiently drills through the casing and cement to access the formation and its fluids—unlike traditional cased hole formation testers, which rely on explosive charges to establish communication with the formation—there is no explosive shock compromising the seal between the tester and the casing to prevent obtaining valid pressure measurements, conducting pretests, or sampling fluids. Conventional cased hole pretests are also difficult to analyze because the penetration depth of the explosive charges is uncontrolled.

The InSitu Fluid Analyzer real-time downhole fluid analysis system can be deployed with the CHDT tester to comprehensively measure the sampled fluid at reservoir conditions, spanning direct indicators of fluid sample purity to extensive downhole fluid analysis.