1、 Standard Material Requirements Metallic Materials for Sucker-Rod Pumps for Corrosive Oilfield Environments This NACE International standard represents a consensus of those individual members who have reviewed this document, its scope, and provisions. Its acceptance does not in any respect preclude
2、anyone, whether he or she has adopted the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not in conformance with this standard. Nothing contained in this NACE standard is to be construed as granting any right, by implication or otherwise, to m
3、anufacture, sell, or use in connection with any method, apparatus, or product covered by letters patent, or as indemnifying or protecting anyone against liability for infringement of letters patent. This standard represents minimum requirements and should in no way be interpreted as a restriction on
4、 the use of better procedures or materials. Neither is this standard intended to apply in all cases relating to the subject. Unpredictable circumstances may negate the usefulness of this standard in specific instances. NACE assumes no responsibility for the interpretation or use of this standard by
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6、 health, safety, environmental, and regulatory documents and for determining their applicability in relation to this standard prior to its use. This NACE standard may not necessarily address all potential health and safety problems or environmental hazards associated with the use of materials, equip
7、ment, and/or operations detailed or referred to within this standard. Users of this NACE standard are also responsible for establishing appropriate health, safety, and environmental protection practices, in consultation with appropriate regulatory authorities if necessary, to achieve compliance with
8、 any existing applicable regulatory requirements prior to the use of this standard. CAUTIONARY NOTICE: NACE standards are subject to periodic review, and may be revised or withdrawn at any time in accordance with NACE technical committee procedures. NACE requires that action be taken to reaffirm, re
9、vise, or withdraw this standard no later than five years from the date of initial publication and subsequently from the date of each reaffirmation or revision. The user is cautioned to obtain the latest edition. Purchasers of NACE standards may receive current information on all standards and other
10、NACE publications by contacting the NACE FirstService Department, 1440 South Creek Dr., Houston, TX 77084-4906 (telephone +1 281-228-6200). Reaffirmed 2012-06-05 Reaffirmed 2006-03-11 Reaffirmed 2000-03-28 Revised October 1994 Approved January 1976 NACE International 1440 South Creek Drive Houston,
11、TX 77084-4906 +1 281-228-6200 ISBN 1-57590-099-8 2012, NACE International NACE Standard MR0176-2012 Item No. 21303 MR0176-2012 NACE International i _ Foreword This standard specifies metallic material requirements for the construction of sucker-rod pumps for service in corrosive oilfield environment
12、s. American Petroleum Institute (API)(1(1) Spec 11AX1 provides dimension requirements that ensure the interchangeability of component parts. However, that document does not provide material specifications or guidelines for the proper application of various API pumps. API RP 11AR2 does list the gener
13、al advantages and disadvantages of the various pump types and lists the acceptable materials for barrels and plungers; and API RP 11BR3 supplements API Spec 11AX by providing corrosion control methods using chemical treatment. This NACE standard is intended for end users (e.g., production engineers)
14、 and equipment manufacturers to supplement the use of the aforementioned API publications. This standard was originally published in 1976 and was revised in 1994 by NACE Task Group T-1F-15 on Sucker-Rod Pumps for Corrosive Environments, a component of Unit Committee T-1F, “Metallurgy of Oilfield Equ
15、ipment.” It was reviewed by Task Group T-1F-28 and reaffirmed by T-1F in 2000, and was reaffirmed in 2006 by Specific Technology Group (STG) 32, “Oil and Gas ProductionMetallurgy;” and in 2012 by STG 32. This standard is issued by NACE International under the auspices of STG 32. In NACE standards, t
16、he terms shall, must, should, and may are used in accordance with the definitions of these terms in the NACE Publications Style Manual. The terms shall and must are used to state a requirement, and are considered mandatory. The term should is used to state something good and is recommended, but is n
17、ot considered mandatory. The term is used to state something considered optional. _ (1) American Petroleum Institute (API), 1220 L St. NW, Washington, DC 20005-4070. MR0176-2012 ii NACE International _ NACE International Standard Material Requirements Metallic Materials for Sucker-Rod Pumps For Corr
18、osive Oilfield Environments Contents 1. General 1 2. Description of Tables .1 3. Barrel Selection .2 4. Pump Selection 2 5. Maintenance Record System .3 References 14 Appendix A: Economic Benefits (Nonmandatory) 14 Appendix B: Case-Hardening Processes for Steel Pump Barrels for a Corrosive Environme
19、nt (Nonmandatory) . 15 TABLES: Table 1: Classification of Metal-Loss Corrosion for Sucker-Rod Pumps(A) 4 Table 2: Recommended Materials for Mild Metal-Loss Corrosion Environments .5 Table 3: Recommended Materials for Moderate Metal-Loss Corrosion Environments 6 Table 4: Recommended Materials for Sev
20、ere Metal-Loss Corrosion Environments 7 Table 5: Typical Mechanical Properties of Pump Barrel Materials .8 Table 6: Typical Mechanical Properties of Plunger Materials 11 Table 6.1: Typical Chemical Composition of Spray Metal 12 Table 7: Typical Materials for Cages . 12 Table 8: Typical Materials for
21、 Pull Tube, Valve Rod, and Fittings 13 Table 9: Typical Composition and Hardness of Cast Cobalt Alloys Used for Valve Parts . 13 Table 10: Typical Composition and Hardness of Sintered Carbides Used for Valve Parts 13 _ MR0176-2012 NACE International 1 _ Section 1: General 1.1 An adequate chemical tr
22、eatment program using a selection of proper corrosion inhibitors and application techniques is necessary for optimum performance of sucker-rod pumping equipment in a corrosive environment. However, control of direct attack on pump materials may be accomplished by materials selection alone or by mate
23、rials selection in combination with chemical treatment. 1.2 The recommended materials in this standard are presented in tables and listed in order of preferred usage in six different environments with varying degrees of corrosiveness and with and without possible abrasion. The listed materials have
24、performed satisfactorily when used in the specified environments. These material recommendations are based on field experience. 1.3 This standard is not intended to preclude the development and testing of new materials that might improve sucker-rod pump performance. It is the responsibility of the u
25、ser to fully evaluate the performance of any new material prior to its use. 1.4 The designations and mechanical properties of the materials covered by this standard are listed in selected tables. _ Section 2: Description of Tables 2.1 The specific quantities of water, hydrogen sulfide (H2S), and car
26、bon dioxide (CO2) that are used to classify the corrosiveness of a fluid as mild, moderate, or severe are detailed in Table 1. 2.1.1 Explanations of the mild, moderate, and severe metal-loss corrosion classifications provided in Table 1 are intended to be a guide for the user. Currently, there is no
27、 clear consensus on which combination of produced fluids constitutes mild, moderate, or severe corrosive environments for subsurface pumps. There can be amounts of H2S, CO2, and water that do not clearly fall into one of the three combinations. The users operating experiences coupled with analysis o
28、f failures should be used to develop the appropriate classification. 2.1.2 The three corrosion classifications are identified by amounts of water, H2S, and CO2 in the produced fluids. There are other constituents in the fluid that can influence corrosion. General comments on these constituents follo
29、w: 2.1.2.1 OxygenOxygen can be very destructive to the system. If oxygen is discovered, every attempt should be made to free the system of oxygen, or at least bring it to below 50 ppb dissolved oxygen. Severe corrosion can be expected above 50 ppb dissolved oxygen. 2.1.2.2 ChloridesHigh chlorides ca
30、n lead to pitting corrosion. High-chloride service conditions should be assumed to exist when the total dissolved solids exceed 10,000 mg/L and/or total chlorides exceed 6,000 mg/L. 2.1.2.3 H2S (Sour Service)Sour service conditions should be assumed to exist when H2S is present in the system at part
31、ial pressures equal to or greater than 0.35 kPa absolute (0.050 psia). When operating in sour service, the material for subsurface pump fittings (connectors, bushings, etc.) should conform to the requirements of NACE MR0175/ISO 15156.4 2.1.2.4 Water ContentGenerally, if the water content is greater
32、than 20%, the fluid exists as a water phase with oil droplets. If the water content is less than 20%, an oil phase with water droplets can exist. Inhibitors should be used if the water content is greater than 20%. 2.1.2.5 TemperatureThe higher the temperature, the greater the rate of corrosion. Temp
33、erature below the crystallization point of paraffin results in deposition of a film of paraffin that may act as a corrosion barrier. 2.1.2.6 pHThe pH at bottomhole conditions is frequently lower (more acidic) than that measured at the surface. After acidizing, the pH should be monitored to ensure th
34、at the fluid does not attack chrome plate if chrome plate is used in the pump. MR0176-2012 2 NACE International 2.1.2.7 PressurePressure does not have a direct influence on the general corrosion rate. However, the system pressure influences the partial pressures of H2S and CO2, which have an effect
35、on the corrosive nature of the fluids. 2.1.2.8 VelocityGenerally, the higher the velocity of produced fluids through the pump, the greater the metal loss because of erosion-corrosion. 2.1.2.9 AbrasionAbrasion results not only from produced fluids but also from corrosion byproducts (e.g., iron sulfid
36、e). If the fluids contain greater than 100 ppm solids, conditions are considered abrasive. 2.2 General definitions of mild, moderate, or severe corrosive environments follow: 2.2.1 Mild metal-loss corrosive environment: Corrosion attack on downhole equipment, rods, and tubing is evident but equipmen
37、t may last several years (more than three years) either with or without inhibitor treatment before corrosion-related failures occur. 2.2.2 Moderate metal-loss corrosive environment: Corrosion rates and time-to-failure are between mild and severe. 2.2.3 Severe metal-loss corrosive environment: Corros
38、ion rates are high and corrosion failures occur in less than one year unless effective inhibitor treatment is applied. 2.3 Recommended materials for sucker-rod pumps to be used in mild, moderate, and severe metal-loss corrosive environments are listed in Tables 2, 3, and 4, respectively. The tables
39、are each divided into two degrees of abrasion (i.e., “no abrasion” and “abrasion”) for each of the three corrosive environments. 2.4 A determination of the correct environmental classification for the selection of the materials to be used in a particular well should be made by an experienced corrosi
40、on or materials specialist. 2.5 The recommended pump barrels and compatible plungers are the first items shown under each environment. A plunger can be used with more than one barrel, but this could alter the preferred order of usage. 2.6 The tables showing barrel/plunger combinations also show the
41、recommended material selections for valves, cages, pull tubes, valve rods, and fittings. 2.7 Materials for all parts are listed in preferred order based on optimum operating costs as determined by field experience rather than expected pump life or initial cost. In some instances, performance of thes
42、e recommended materials can be similar. The total costs of pump repairs and proper material selection are discussed in Appendix A: Economic Benefits (Nonmandatory). _ Section 3: Barrel Selection 3.1 Mechanical properties of the various pump barrel base materials and available surface-conditioning re
43、quirements of barrels are given in Table 5. 3.2 There is no significant difference in corrosion performance between the D1 and D4 non-hardened steel barrels. 3.3 Generally, the corrosion performance of the four different case-hardened barrels is comparable. Case-hardening processes recommended for s
44、teel pump barrels to be used in H2S environments are discussed in Appendix B: Case-Hardening Processes for Steel Pump Barrels for a Corrosive Environment (Nonmandatory). _ Section 4: Pump Selection 4.1 Interrelated factors, other than the corrosive and abrasive natures of the produced fluids, that s
45、hall be considered when selecting materials for a sucker-rod pump include: 4.1.1 Type of pump; MR0176-2012 NACE International 3 4.1.2 Barrel length and diameter; and 4.1.3 Seating depth and required material strength. 4.2 For a given pump size and seating depth, the strength requirement for a barrel
46、 in a top hold-down pump is greater than that for a barrel of a bottom hold-down pump. This is the result of a top hold-down pump having a greater pressure differential across the barrel. 4.3 Materials should be selected from Tables 2 through 10 to meet the strength and hardness requirements dictate
47、d by the type of pump and anticipated operating conditions. 4.4 Tables 5 through 8 list many of the materials by specific alloy number. 4.4.1 When selecting pumps, the purchaser should be aware that common names, brass for example, are often used to describe alloys of significantly different compositions and properties. 4.4.2 Specific alloys should be designated as shown in the tables to prevent substitution of trade name materials with different composition, which has resulted in repetitive failures in the past. _ Section
