Apparatus and method for analyzing well fluid sag
US6584833B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 2002 |
| Grant date | Jul 1, 2003 |
| Priority date | — |
| Expiry date | May 30, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2203/0676
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method are disclosed for measuring or analyzing dynamic and static sag caused by settling of weighting materials in drilling fluids or other solids bearing fluid. The apparatus comprises a tube and shear shaft assembly that allows for a controlled rate of shear to be applied to a sample of the fluid for testing. During a test, the assembly is placed on a pivotal holder at an angle. The assembly has pistons at the pivot center of the assembly which accommodate expansion and contraction of the test fluid due to changes in temperature and pressure, thereby allowing the test fluid to be heated, cooled and pressurized to simulate subterranean wellbore conditions without changing the center of mass of the test fluid. When weight material settles down the inclined assembly, the center of mass of the assembly changes resulting in changing torque or moment about the pivotal holder. The resultant moment is measured by energizing external coils arranged to provide a uniform magnetic field. The bulk average settling rate is determined using the measured coil current rate of change.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.