Rock Compressibility System

The Rock Compressibility System CT-RCM subjects a saturated core plug to controlled confining pressure, pore pressure and axial stress and measures the resulting volume change, from which pore-volume and bulk compressibility are calculated. The results feed reservoir compaction, subsidence and material balance analysis. Plugs of 1 in, 30 mm and 1.5 in diameter and up to 4 in length are tested at up to 100 MPa confining pressure, 100 MPa pore pressure and 100 MPa axial stress, from ambient to 150 °C.

How it works

The specimen is sealed in the pressure vessel and confining and pore pressure are brought to the starting state. The operator then runs a loading and unloading path, for example one that follows the stress path of the reservoir during production, while the pore-fluid control and volumetric measurement track pore-volume change at each pressure step. In-vessel strain sensors read axial strain directly, so compaction is measured on the sample itself and uniaxial-strain compressibility tests can be run; the method accounts for inelastic behavior of the rock.

Reported outputs are pore-volume change versus pressure and the calculated pore-volume and bulk compressibility. Wetted construction is stainless steel or Hastelloy, and the system runs on 220 VAC, 50 Hz. The pressure envelope and specimen size are configured per project.

What is included

• Pressure vessel for 1 in, 30 mm and 1.5 in plugs up to 4 in long
• Pore-fluid control
• Volumetric measurement
• In-vessel strain sensors for uniaxial-strain tests

Specify for your project

• Plug diameter and length
• Maximum confining pressure, pore pressure and axial stress, up to 100 MPa each
• Test temperature, ambient to 150 °C
• Stress path to be followed: hydrostatic or uniaxial strain, loading and unloading steps
• Pore fluid and wetted material, stainless steel or Hastelloy
• Site power supply

This description defines the product family. Guaranteed performance, included hardware, exclusions, interfaces and acceptance criteria are stated only in the project-specific technical proposal and approved datasheet.

Features

• Core Diameter: 1 inch, 30 mm and 1.5 inches
• Core Length : up to 4 inches
• Max pore pressure : 100 Mpa
• Max confining pressure : 100 Mpa
• Max axial stress : 100 Mpa
• Working temperature : ambient to 150° C
• Material: Stainless steel or Hastelloy
• Power supply: 220VAC, 50Hz

Benefits

• Includes in-vessel strain sensors for uniaxial-strain compressibility tests
• Simulates actual reservoir production stress path
• Accounts for inelastic behavior of reservoir rock
• Measures compaction directly from axial strain