Moyno 280XT Elastomer. Operational Guidelines

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1 Moyno 280XT Elastomer Operational Guidelines

2 Moyno 280XT Elastomer Operational Guidelines Index 1. Overview Field Test Observations Recommended Operational Compressions... 3 Adjusting the Temperature Range Based on Actual Shop Fit... 4 Sensitivity of Operational Compression Recommendations... 4 Differential Pressure Loading XT Fit Recommendations The designs and specifications for the tools described in this instruction manual were in effect at the time this manual was approved for printing. National Oilwell Varco, whose policy is one of continuous improvement, reserves the right to discontinue models at any time, or to change designs and specifications without notice or without incurring obligation.

3 1. Overview One of the purposes of the 280XT field test program was to establish relationships between reliability and operational loading that would form the basis for Operational Guidelines upon 280XT commercialization. Operational compression (e.g. fit ) is of particular interest with 280XT because its high compressive strength will induce more stress into the elastomer for a specific compression level than will a softer elastomer. Field performance and reliability during the program was excellent if both the operational compression and differential pressure loading recommendations were followed, so a high degree of confidence has been gained concerning the appropriateness of the recommendations contained in this document. 2. Field Test Observations The following was learned during the field test program: The minor diameter of 280XT stators has always gotten larger during use, reducing operational compression. Compression set and wear are the root causes of the observed diameter change and their contribution to the change will vary based on the application. This result is not common in power section elastomers and it s a reflection of 280XT s excellent fluid compatibility. The increase in 280XT minor diameter is desirable since it dovetails with the natural tendency for wells to get hotter with increased measured depth. As temperatures increase, 280XT naturally decreases its operational fit to reduce elastomer stress. An elastomer that has experienced compression set does not fully rebound to its initial shape after loading. It s thought that in a power section the majority of the compression set is realized in the first hours of operation and the rate of change will decline after that. 280XT stators continued to produce significant power and torque even after a clearance fit was obtained. High ROPs were also obtained with operational fits below 1%, so elevated operational fits are not needed for fast drilling. Only one stator failed during the test program and its operational fit exceeded 3%. 2. Recommended Operational Compressions Based on the above, the following green operational compression range is considered optimal, while the other zones are acceptable, but suboptimal and they therefore may result is reduced performance. Compression % Comments = ~ 0.5 to 1.0% This range is considered sub-optimal but acceptable. Due to observed 280XT wear rates the possibility exists that a clearance fit will be obtained during the run. Field tests, however, indicate that this may not necessarily result in an observable decline in ROP. = ~ 1.0 to 2.0% This is the preferred, optimal compression range. Based on observed wear rates, it s expected that operational compression will be maintained during the entire run. = ~ 2.0 to 2.5% This range is above optimal levels and operational data is insufficient to comment on life expectancy. The initial compression represents a worst case loading, which will likely get into the green zone after hours of operation as compression set is realized. The tables on pages 5 and 6 identify the temperatures at which the above compressions would be realized for the models that have been evaluated. The temperature ranges for each fit are not absolute and will change based on the actual rotor and stator dimensions. They should therefore be used for reference and size selection purposes only. The actual temperature ranges associated with each zone can be estimated by using the Change in range for shop fit change number in the far right column. The example on page 4 shows how this is done: downhole@nov.com 3

4 Moyno 280XT Elastomer Operational Guidelines Adjusting the Temperature Range Based on Actual Shop Fit: Model = 475M Actual shop fit = Change/0.001 = 5.3 F Nominal Shop fit = Discussion: The shop fit is tighter than nominal. The 2 temperature range should be moved 21 F to the left due to the tighter fit (i.e. 5.3 F x 4 = 21.2 F). The new green zone range is ~ F instead of the nominal F. Sensitivity of Operational Compression Recommendations The operational temperatures for which operation of a specific 280XT power section fit is recommended are not absolute. In other words, if the recommended temperature range is F, going from 225 F to 230 F does not mean that the stator will experience damage at 230, but not at 225 F. Inaccuracies in measurements and the contribution of other operational loading conditions will also affect the temperature range in which 280XT can be used. A good practice is to reduce the loading provided by another operational factor, say differential pressure or flow rate, if the calculated operational fit is at or above the top of the recommended temperature range. Differential Pressure Loading 280XT field testing has shown that a differential pressure loading of up to 100 psi/stage at 250 F produces a desirable combination of ROP and reliability. Although this loading level is the same as that recommended for UF114, 280XT has drilled at rates much higher than UF114, sometimes drilling over 3,000 ft in 24 hours. This is due to 280XT s enhanced mechanical properties that improve the ability of a conventional power section to respond to instantaneous bit torque demands and increase the effective transfer of power to the formation. The graph below describes the maximum recommended pressure/stage for 280XT for different operational temperatures. Loading recommendations change based on temperature due to an elastomer s natural tendency to loose strength as operational temperature increases. Pressure / Stage psi (kpa) 150 (1035) 125 (860) 100 (690) 75 (515) 50 (345) Max Recommended Differential Pressure / Stage (170) (66) (79) (93) (107) (121) (135) (149) (163) (177) (191) Operational Temperature o F ( o C) 4

5 4. 280XT Fit Recommendations (October 2012) 475M4563 o F M o F M7826 Std Std o F M o F 475M o F M o F 475M91040 Std STD o F M6780 Std Std Nominal Shop Fit Minor Diameter Average Rotor Diameter Change in range for shop fit change o F o F o C Operational Compression =~0.5 to 1.0% =~1.0 to 2.0% =~2.0 to 2.5% compression 5 downhole@nov.com

6 Moyno 280XT Elastomer Operational Guidelines 280XT Fit Recommendations (Continued) 650M91040 Std Std o F 675M o F 675M o F M5650 o F Shop Nominal Fit Std o F 675M o F M7821 HT Std Std o F 675M7829 HT o F 675M o F M7833 HTS o F 675M7835 HTS o F 675M o F M o F M o F 800M o F Minor Diameter Average Rotor Diameter Change in range for shop fit change o C Operational Compression =~0.5 to 1.0% =~1.0 to 2.0% =~2.0 to 2.5% compression 6

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8 Downhole Solutions Drilling Solutions Engineering and Project Management Solutions Corporate Headquarters 7909 Parkwood Circle Drive Houston, Texas United States Phone: Fax: Industrial Solutions For a complete list of NOV Downhole locations, visit us online: Lifting and Handling Solutions Production Solutions Supply Chain Solutions National Oilwell Varco has produced this brochure for general information only, and it is not intended for design purposes. Although every effort has been made to maintain the accuracy and reliability of its content, National Oilwell Varco does not warrant the accuracy or completeness of any data or information contained herein. National Oilwell Varco in no way assumes responsibility for any claim or liability for any loss, damage or injury related to or arising from the use and/or interpretation of the data and information contained herein. The user retains full responsibility for all inferences drawn or decisions made in connection with any such information and data or interpretations of such information and data, and all applications for the material described are at the user s risk and are the user s responsibility. Tubular and Corrosion Control Solutions Well Service and Completion Solutions One Company... Unlimited Solutions downhole@nov.com National Oilwell Varco D MKT-001 Rev. 01

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