Gas Well De-Liquification Workshop. Capillary Tubing Metallurgical Considerations in Application. Adams Mark Hotel, Denver, Colorado March 5-7, 2007

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1 Gas Well De-Liquification Workshop Adams Mark Hotel, March 5-7, 2007 Capillary Tubing Metallurgical Considerations in Application Ben Horn Weatherford International

2 What metallurgy is appropriate? Considerations Partial pressures of H 2 S & CO 2 Chlorides, temperature, ph Depth Evaluation applies practice outlined by Schillmoller in Selection of corrosion-resistant alloy tubulars for offshore applications Nickel Development Institute,1989 2

3 H 2 S & CO 2 Considerations Partial Pressure CO2 4% CO 2 Est +/- 500 avg pressure in tubulars PP CO 2 = 500psi X = 20 psi Partial Pressure H2S 20 ppm H 2 S Est +/- 500 avg pressure in tubulars PP H 2 S = 500psi X = psi 3

H 2 S & CO 2 Considerations 100000 Selection Guide Selection Guide Corrossion Resistant Alloy Tubulars in Gas Wells Corrosion Resistant Alloy Tubulars in Gas Wells 10000 Alloy 625 1000 Duplex 2205

4 H 2 S & CO 2 Considerations Selection Guide Selection Guide Corrossion Resistant Alloy Tubulars in Gas Wells Corrosion Resistant Alloy Tubulars in Gas Wells Alloy Duplex 2205 Partial Pressure of CO 2, psia Super Duplex Alloy 300 series From Schillmoller, 1989 Selection of Corrosion -Resistant Alloy Tubulars for Offshore Applications Partial Pressure of H 2 S, psia Instructions: 1. Calculate partial pressures of H 2 S and CO 2. PPCO2 = mole % CO 2 X pressure PPH2s = mole % H 2 S X pressure 2. Enter X and Y axes appropriately 3. Select Alloy based on Color Scheme 4. Proceed to Chloride Pitting Charts to further delineate total treatment recommendation 4

5 Chlorides, Temperature and ph Considerations Most Gas Fields are Mild or Moderate Environments BHT = F Moderate CO2, Low H2S Reasonable phs 5

6 Chlorides, Temperature and ph Considerations T<230 o F Region Of Most Oil Field Brines 6

7 Chlorides, Temperature and ph Considerations 230 o F<BHT< F<T<390 o F390 o F Region Of Most Oil Field Brines 7

8 Physical Properties Capillary Coiled Tubing Some Considerations: (1) How much pull can I place on a string before it exceeds yield stength of metallurgy? (2) How deep can I run the string? 8

9 Physical Properties Capillary Coiled Tubing Stainless Steel Tubing Stretch Calculator Capillary Technologies Engineered Chemistry TM Data Section Calculations Tubing Data Weight Calculations Tubing Material Super Duplex 2507 Tubing Weight 1440 lbs Tubing OD in Chemical Weight 198 lbs Tubing WT (wall thichness) in Pump Pressure Force 0lbs Tubing WGHT 80 lbs/1,000 ft Pull Force 0lbs Tubing Set Depth 18,000 ft Total Force to cause 80% Yield Failure 1513 lbs CAUTION Tubing Tensile Strength 120 X10 3 psi Total Force to cause Yield Failure 1891 lbs OK Tubing Yield Strength 80 X10 3 psi Total Force to cause Tensile Failure 2837 lbs OK Tubing Modulus of Elasticity 29 X10 6 psi Chemical Data Total Tubing "Effective" Weight 1638 lbs Chemical Material Chemical Dernsity WFT 97111W 8.33 lb/gal X-Section Calculations Calculations Is string full of Chemical? Y Y/N Metal X-Section Area in 2 Pump Data psi ID X-Section Area in 2 Pump Pressure 0 OD X-Section Area in 2 Pull Data lbs Elongation Calculations Pull Force 0 Tubing Elongation due to Tbg Weight 37.8 ft Temperature Data o F Tubing Elongation due to Chemical Weight 5.2 ft Ambient Temperature 80 o F Tubing Elongation due to Pump Force 0.0 ft Well Temperature 220 Tubing Elongation due to Pull Force 0.0 ft Tubing Elongation due to Temperature Effect 18.1 ft Note : Total Tubing Elongation (1) All calculations assume tubing is hanging in air with CC1-A valve in place on end of string. (2) External/Negating forces that would reduce stretch are ignored. This is a worse case stretch evaluation. (3) If "CAUTION" Shows up, Effective Weight exceeds 80% Yield Strength of Tubing - Getting close to Tubing Deform (4) If "ALARM" Shows up, Effective Weight exceeds Yield Strength of Tubing - Tubing will permanently Deform. (5) If "FAILURE" Shows up, Effective Weight exceeds Tensile Strength of Tubing - Tubing will part ft 9

organic polymer in the chemical and excretes H2S High operating pressures inside the capillary

10 Super-Duplex 2507 Tubing South Texas Application Point of Failure Failed from Pitting Inside out Occasionally, bacteria can pollute the injection chemical system Bacteria consumes the organic polymer in the chemical and excretes H2S High operating pressures inside the capillary string (by design) create high partial pressures As predictable Tubing pits and or cracks and fails 10

11 Physical Properties Capillary Coiled Tubing Conclusion Rule of Thumb Considerations: Partial Pressures H2S and CO2 Unless there is extremely high partial pressures of H 2 S most often, Standard Duplex 2205 tubing is sufficient Chlorides and ph Most often a function of Temperatures. Below 235 o F, normal salinities, Standard Duplex 2205 is sufficient for corrosion stress cracking. Above 235 o F, normal salinities, Inconel 625 is more appropriate. The closer to the line, judgement call of operator. Just need to understand the risks and consequences Depth Function of Yield strength of material and desired working range in the event of future remedial work 11

Titanium Production Tubing for HPHT Oil & Gas Wells. Jonathan Parry Chevron Jim Grauman TIMET

Titanium Production Tubing for HPHT Oil & Gas Wells Jonathan Parry Chevron Jim Grauman TIMET Overview Titanium alloy seamless pipe manufacturing & application Titanium advantages over high chrome/nickel