FE 02-13 Intro to Testing

Nội dung text: FE 02-13 Intro to Testing

1. Testing 1. Hydrocarbons rising under pressure 2. Gauge measuring pressure variation • The formation test is the final proof of a well's profitability
2. Wireline Formation Test • A quick, inexpensive way to measure pressures at specific depths • Useful for investigating oil and gas shows, taking quick readings of hydrostatic and flow pressure, and confirming porosity and permeability data from other logs • They allow general predictions for zone productivity and may be used in planning more sophisticated formation tests • Run on conductor line and may be run with a logging sonde (SP or GR or CCL) or with a bottomhole pressure gauge • The test tool is made up of a rubber pad with a valve in it, a pressure gauge, and testing chambers and sampling chambers interconnected by valves
3. Repeat Formation Tester (RFT) • A readout of formation pressure can be obtained a number of times • At anytime 2 chambers in the tool may be filled with fluids
4. Drill Stem Test (DST) • Has become a kind of temporary, partial completion of the well that provides data on several feet or several hundred feet of producing formation • The main goal of drill stem testing is pressure data
5. DST Procedures 1. Mud in the wellbore is well circulated and conditioned 2. A cushion of water or compressed gas, usually nitrogen, is often placed in the drill stem when the DST tool is run in 3. After the pressure charts are loaded and the DST tool is laid out and ready to run 4. The proper length of anchor pipe is tripped in to situate the test assembly at the chosen depth 5. All test assembly parts are then added. Sometimes drill collars are made up above the tool as a precaution against collapse if no cushion is used
6. DST Procedures 10. The strength of this first flow is estimated. From this estimate the number and lengths of the flow and shut-in periods for the rest of the test are chosen. 11. Most DST’s include two flow and shut-in periods, the second round being given more time than the first. Some longer tests have three rounds. Each round includes a flow period followed by a shut-in period to record hydrostatic formation pressure. The short first round clears out any pressure pockets in the wellbore and removes mud from the drill stem.
7. End of Topic