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WG on Determination of Fluid Loss Screen Life. API SC 10 Scott Jennings 25 June, 2013 2013 Exploration and Production Standards Conference on Oilfield Equipment and Materials. Current Situation. Currently, Sec. 10 Static fluid-loss tests
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WG on Determination of Fluid Loss Screen Life API SC 10 Scott Jennings 25 June, 2013 2013 Exploration and Production Standards Conference on Oilfield Equipment and Materials
Current Situation • Currently, • Sec. 10 Static fluid-loss tests • The screens shall be replaced when they show visible plugging, wear, • damage, or distortion. (API RECOMMENDED PRACTICE 10B-2 • SECOND EDITION, APRIL 2013) • Problems noticed when testing FLAs for acceptance criteria & comparing FL data with SC. • API spec for Blade Wear: • Discard if mass loss >10 %
Review • Average of 11 tests • ARAMCO vs SC A = 15.3% • ARAMCO vs SC B = 45.8% • ARAMCO vs SC C = (-13.6%)
Used FL Screens • 13 used screens weighed (metal backed) • Ave. 20.33 gr. • High 22.59 gr. • Low 19.31 gr. • 5 screens selected for water flow test • Weight (high and low) • Visibility (best and worst) • Water gravity flow test • 165 grams of water flow through cell (SG-1.00) • 3 test times recorded (sec) • Rates calculated (ml/sec)
Future Work 21.99 New 4.03 Any Interest to Pursue?
Needed volunteers to run the non perforated disk backed screen • CSI • ran 30 tests • Chandler Engineering • designed water test Apparatus • Saudi Aramco (perforated disk) • ran 10 more test (total 30 tests) • 10 tests with Latex cement
CSI Testing • Procedure from previous testing used • Newer non-backed screens used • Two slurries tested
Slurry #1 • 16.4 ppg Class H + 0.3% bwoc fluid loss additive • Ten fluid loss tests run • Initial fluid loss: 46 ml • Final fluid loss: 37 ml • Initial screen weight: 19.202 g • Final screen weight: 19.252 g • Initial average water flow rate: 8.02 ml/sec • Final water flow rate: 0.26 ml/sec
Slurry #2 • 16.4 ppg Class H + 0.2% bwoc fluid loss additive • Ten fluid loss tests run • Initial fluid loss: 207 ml • Final fluid loss: 215 ml • Initial screen weight: 19.252g • Final screen weight: 19.594 g • Initial average water flow rate: 0.4 ml/sec • Final water flow rate: 0.11 ml/sec
Pre Slurry #2 Post FL #2 Post FL #3
Post FL#4 Post FL #5 Post FL #6
Post FL #8 Post FL #9 Post FL #10
3 Choices • Change complete screen every time • Costly • Change the 325 mesh screen every time (split rings) • 60 mesh screen half thickness ring 325 mesh on top and blank ring on top. Need perforated disk type for strong backing • Use Plastic FL screen tester to determine flow rate • Continue with screens currently provided
Water Tests Variable Results • Aramco flow rate • 3.95 ml/sec screen backing • 4.03 ml/sec perforated backing • Chandler flow rate • 1.96 ml/sec screen backing • CSI flow rate • 1.69/1.83 ml/sec screen backing
Choice 2 Split ring New 325 mesh screen every test Metal support ring 60 mesh screen or Perforated disk 325 mesh screen
Choice 3 – Use Fluid Loss Screen TesterDrawings by Chandler Engineering
Work Continues with Water Tester Fabrication in Progress
Lab – Lab Results • Variables running the test are: • Technician – accuracy of performing FL test • Pressure delivered • Screen • Visibility • Weight • Flow rate
Initial Findings • Labs discard screens at technician discretion (Vis.). • Unattended test lead to higher degree of uncertainty. • Tech. around but not totally on top of test. • N2 source should have a defined min. starting supply pressure for the static test. • regulated pressure down to 1000 psi diff. • 1200 psi on stirred FL apparatus
Flow Rate Determination Procedure (New Screen) Weigh FL screen dry Soak in water for 2 mins. Assemble FL cell Fill cell with 165 gr. Water SG=1.00 Open drain valve and start clock simultaneously Stop clock and record time when water level has left the inside of the cell. Dry with compressed air Repeat steps 4-7 four more times
Initial Study • 26 new screens weighed (metal backed) • Ave. 21.99 gr. • High 22.24 gr. • Low 21.52 gr • 5 screens selected for water flow test • Water gravity flow test • 165 grams of water flow through cell (SG-1.00) • 5 test times recorded (sec) • Rates calculated (ml/sec) • Best match to average was selected (screen no. 5)
New FL Screen no. 5 Selected 20 FL Tests Performed • 10 slurries selected 115-283 cc’s/30 mins. • Screen weighed before FL test • Water Flow Rate determined before FL test • 2 tests made 30 mins. • Same 10 slurries repeated 120-215 cc’s/30 mins. • Screen weight increased from 22.01 to 22.08 gr. • 4 tests made 30 mins. • Can continue if SC 10 is interested.
Flow Rate Determination Procedure (Used Screen) • Weigh FL screen dry • Soak in water for 2 mins. • Assemble FL cell • Fill cell with 165 gr. Water SG=1.00 • Open drain valve and start clock simultaneously • Stop clock and record time when water level has left the inside of the cell. • Dry with compressed air • Repeat steps 4-7 twomore times