Beam Pumping Workshop Houston Texas October 4 7
Beam Pumping Workshop Houston, Texas October 4 - 7, 2005 Premium MMS-NR (AISI 4138 M) Sucker Rods Alejandro F. Ameglio – Head Technical Services Tenaris Rods Division
Contents • Chemical Analysis • Mechanical Properties • Laboratories Tests • Field experiences • Conclusions 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 2
Chemical Analysis Element Grade UHS-NR (4330 M) Grade MMS-NR (4138 M) Grade Plus (1530 M) C (Carbon) 0. 30 -0. 35 0. 38 -0. 43 0. 31 -0. 36 Mn (Manganese) 0. 70 -0. 95 1. 10 -1. 40 1. 4 -1. 6 S (Sulfur) 0. 025 Mx. P (Phosphorus) 0. 025 Mx. Si (Silicon) 0. 15 -0. 35 0. 20 -0. 40 0. 25 -0. 40 Ni (Nickel) 1. 65 -2. 00 0. 30 Mx. 0. 15 Mx Cr (Cromium) 0. 80 -1. 10 0. 60 -0. 90 0. 2 Mx Mo (Molibdenum) 0. 20 -0. 30 0. 25 -0. 35 0. 05 Mx V (Vanadium) 0. 035 -0. 07 0. 04 -0. 07 0. 10 -0. 15 Nb Cu (Copper) 0. 025 -0. 045 0. 25 Mx. As it can be observed, main difference between Grades UHS-NR and MMS-NR is the Nickel (Ni) content. 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 3
Mechanical Properties Grade UHS-NR (4330 M) Grade MMS-NR (4138 M) Grade Plus (1530 M) YTS (ksi) 115 Min. UTS (ksi) 140 -160 Normalized Thermal process Partially tempered Mechanical properties are the same for all Grades 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 4
Lab Tests A set of lab tests were done to evaluate the performance of the different steels at corrosive environments • CO 2 (“sweet” corrosion) • SSC (Sulfide Stress Cracking) Resistance • Localized attack in H 2 S environments Two steels were tested: AISI 4330 M and AISI 4138 M 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 5
Results of Lab tests Lab Tests v At CO 2 environments both steels showed approximately the same performance. v Besides that, AISI 4138 M showed a lower corrosion potential compared with the AISI 4330 M. v Analyzing the behavior of them at H 2 S environments, both showed a poor performance. v None 1/15/2022 of them are recommended for sour service. Premium MMS-NR (AISI 4138 M) Sucker Rods 6
Field history Field experience A major company operates a field at Neuquen Basin (Río Negro Norte Field) v. Going trough a natural declination process, wells were changing the ALIFT systems from ESP to Rod Pumping. v. Main • • characteristics of the field are: Depths: 8200 -9800 ft (2500 -3000 m) Production rates: 300 -600 bfpd (50 -90 m 3/d) Water cuts: 10 -40% Vertical wells v Load levels make Grade D rods not applicable at the first stage of field development 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 7
Field evolution Field experience 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 8
Field evolution Field experience Major problems were related with sucker rod failures 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 9
Field data analysis Field experience As the failures rates were constantly increasing, it was decided to do a complete analysis of the field data A task force that included production engineers and specialized technicians studied data including: • Fluid analysis • Annulus gas determinations (H 2 S and CO 2) • Bacterial measurements (SRB-Sulfate Reducers Bacteria) • Failure analysis (all of the rod failures were analyzed) • Operating conditions (spm, loads, etc) • Handling & care practices, make-up procedures, etc. 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 10
Field data analysis - Conclusions Field experience v Annulus gas determinations showed a low content of CO 2 (partial pressure < 3 psi). From this point of view, there is no a corrosion problem v However, CO 2 in fluid analysis were detected (concentrations between 40 -70 mg/lt) v No H 2 S were detected, neither SRB (Bacteria). v Failure analysis indicated a corrosion-fatigue process as the responsible for the rod breaks. v NACE MR 0175 (carbon steels or low alloy steels should not contain more than 1% of Ni) v As a final conclusion, a change in the steels of HS sucker rods were decided (from AISI 4330 to AISI 4138) v Those wells whit loads level less than 130% (SF=0. 8) (Grade D) will be installed with Grade D rods 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 11
Field evolution after AISI 4138 rods Field experience 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 12
Rod body failures evolution Field Experience 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 13
Premium MMS-NR (AISI 4138) failures evolution Field experience 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 14
Grade of sucker rods installed Field Experience 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 15
Conclusions Ø This material has shown to have a better performance at corrosive environment than the other type of high strength sucker rods previously tested. ØA reduction in the pulling interventions rate (increase in service life) has been observed. Ø Even with a “sweet” corrosive environment (CO 2), and because of its reduced content of Nickel (Ni), the material is less susceptible to corrosion-fatigue processes that were affecting the other type of sucker rods. Recommendations ü As with all of the high strength rods in a corrosive environments, an effective corrosion inhibition program must be applied. ü Besides that, with loads level less than 140% (SF=0. 8) Grade D rods are also an alternative that should be considered 1/15/2022 Premium MMS-NR (AISI 4138 M) Sucker Rods 16
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