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.