What is Well Testing?
Well Test a period of time during which the production of the well is measured to gain more information from the farthest reaches of the reservoir.
Well testing is fundamentally the collecting of “data” from a newly drilled or established oil & gas well.
The major purpose of testing a well drilled into a formation is to determine the ability of the formation to produce reservoir fluids. The basic test method is to create a pressure drawdown(pressure reduction) in the well bore which causes fluids to enter the well bore.
The simultaneous measurement of flow rate and the pressure in the well-bore during production(flowing) or the pressure build-up during a shut in the period can be used to deduce accurate reservoir characteristics for the purpose of reservoir evaluation.
The objectives of an exploration well test usually fall into three major categories:
Reservoir description
-to provide a proper model describing flow from a reservoir.
-Including fluid sampling, measuring the initial pressure.
Reservoir evaluation
-to determine if the reservoir parameters are satisfactory for commercial and economical production.
-Including estimation for reservoir volume, evaluating the well permeability and skin effect and identifying reservoir boundary.
Reservoir management
-to optimize continued production from the reservoir.
-Data collected from “established” wells provides an update on any changes to the well flow characteristics since its initial production, and therefore will also play an important part in future reservoir management decisions.
Well Testing classifications
Productivity tests
-Obtain and analyze representative samples of produced fluids
-Measure reservoir pressure and temperature
-Determine inflow performance relationship and deliverability
-Evaluate completion efficiency
-Characterize well damage
-Evaluate workover or stimulation treatments
Descriptive tests
-Evaluate reservoir parameters
-Characterize reservoir heterogeneities
-Assess reservoir extent and geometry
-Evaluate hydraulic communication between wells
Well test equipment
1,Wellhead X-mas tree
2,Surface Safety valve
3, Desander
4, Upstream data header
5, Choke manifold
6, Midstream data header
7, Three-phase separator
8, Surge tank
9, Oil transfer pump
10, Gauge tank
11, Oil tank truck
12, Flare system
