1、DEUTSCHE NORM November 1998 Evaluation of resistance of steel products to hydrogen induced cracking (HIC) English version of DIN EN 10229 DIN EN 10229 ICs 77.060 Descriptors: Steel, HIC, testing. Bewertung der Bestndigkeit von Stahlerzeugnissen gegen wasserstoffinduzierte Ribildung (HIC) European St
2、andard EN 10229 : 1998 has the status of a DIN Standard. A comma is used as the decimal marker. National foreword This standard has been prepared by ECISS/TC 1. The responsible German body involved in its preparation was the Normenausschu Eisen und Stahl (iron and Steel Standards Committee). EN comp
3、rises 15 pages. No part of this standard may be reproduced without the prior permission of N Deutsches Institut fr Normung e. V., Berlin. :utb Verlag GmbH, D-i0772 Berlin, has the exclusive right of sale for German Standards (DIN-Normen). Ref. No. DIN EN 10229 : 1998-1 English price group 08 Sales N
4、o. 71 08 04.99 EUROPEAN STANDARD EUROPISCHE NORM NORME EUROPENNE EN 10229 March 1998 ICs 77.060 Descriptors: Steel, HIC, testing. English version Evaluation of resistance of steel products to hydrogen induced cracking (HIC) Evaluation de la rsistance des produits en acier la fissuration induite par
5、lhydrogne (HIC) Bewertung der Bestndigkeit von Stahlerzeugnissen gegen wasser- stoffinduzierte Ribildung (HIC) This European Standard was approved by CEN on 1998-03-02. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European St
6、andard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national stand- ards may be obtained on application to the Central Secretariat or to any CEN member. The European Standards exist in three official versions (English, Fren
7、ch, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, the Czech Republic,
8、 Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, and the United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de
9、 Stassart 36, B-1050 Brussels O 1998. CEN - All rights of exploitation in any form and by any means reserved worldwide for CEN national members. Ref. No. EN 10229 : 1998 E Page 2 EN 10229 : 1998 Contents Foreword 3 Introduction . 4 1 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 3 4 4.1 4.2 4.3 4.4 5 6
10、 6.1 6.2 6.3 7 7.1 7.2 7.3 7.4 7.5 8 8.1 8.2 8.3 8.4 9 10 Scope 4 Definitions 4 sample . 4 test piece . 4 section . 5 crack 5 hydrogen induced crack . 5 separation between cracks 5 isolated crack . 5 crack system 5 extent of cracking . 5 stepwise crack . 5 Principle of the method . 6 Test solutions
11、6 Test solution A . 6 Volume ratio . 7 Reagent purity . 7 Apparatus . 7 Test Pieces . 7 Location and orientation . 7 Size 8 Preparation 8 Test procedure . 9 Test batch 9 Degreasing 9 Test piece exposure . 9 De-aeration and saturation 9 Test period . 10 Evaluation of test pieces . 10 Blisters . IO Te
12、st piece sectioning . 10 Preparation of sections 10 Evaluation of cracking 11 Test solution B (synthetic seawater) 6 Ratio calculations 11 Test report 12 Page 3 EN 10229: 1998 Foreword This European Standard has been prepared by Technical Committee ECISSTTC 1 “Steels - Mechanical and physical tests“
13、 the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 1998, and conflicting national standards shall be withdrawn at the latest by September 1998. A
14、ccording to the CENICENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Port
15、ugal, Spain, Sweden, Switzerland and the United Kingdom. Page 4 EN 10229 : 1998 Introduction The need, today, to drill deeper to find oil and natural gas and the procedures that are being used in many fields to enhance oil and gas recovery are resulting in an increase worldwide in the number of fiel
16、ds considered “sour“. This in turn is leading to an increasing demand from oil companies for steels resistant to sour conditions. Flow lines or gathering pipelines in sour fields may be transporting crude oil or natural gas containing significant amounts of hydrogen sulphide (H2S) and water. Additio
17、nally there is increased recognition of the importance of sour operating conditions in pressure vessels and structural steel work. On steel, the presence of water with H,S can cause corrosion. Atomic hydrogen generated by the corrosion reaction can be absorbed into the steel and lead to cracking of
18、the product. Cracks on adjacent planes may link up to form through thickness “steps“ and in some instances surface blistering may occur. Hydrogen induced crackings occurs (HIC) without any applied stresses. The test described in this European Standard is not intended to duplicate service conditions,
19、 nor show how a material will perform in service. It is an accelerated corrosion test designed as a reproducible procedure capable of evaluating the resistance to hydrogen induced cracking. NOTE : A draft “Corrosion Protection - Carbon and allow steels for use in H2S containing environments in oil a
20、nd gas production - Materials requirements and test method“ being currently prepared by CEN/TC 262 “Protection of metallic materials against corrosion“ uses also the term “Step wise cracking (SWC)“. 1 Scope This standard specifies a method of evaluation of the susceptibility to hydrogen induced crac
21、king (HIC) of steel products with nominal thicknesses equal to or greater than 6 mm. NOTE : This standard may be applied by agreement to products with nominal thicknesses lower than 6 mm. This standard does not cover resistance to other types of corrosion such as for example stress corrosion crackin
22、g. 2 Definitions For the purposes of this standard, the following definitions apply. 2.1 sample A sufficient quantity of material taken from the product for the purpose of producing three test pieces, for example : Ring in case of tubes, part of plates. 2.2 test piece Part of the sample with specifi
23、ed dimensions, machined for submission to the test. Page 5 EN 10229: 1998 2.3 section The part which is cut from each test piece after testing, metallographically prepared and examined in order to assess the cracking present. Three sections are taken per test piece. 2.4 crack A more or less planar v
24、oid discontinuity in the steel. 2.5 hydrogen induced crack A crack below and approximately parallel to the surface of the product, initiated and propagated by the action of hydrogen in the steel as a result of contact with a wet sour medium. 2.6 separation between cracks The shortest straight line d
25、istance between two cracks. 2.7 isolated crack A crack separated from the next crack by more than 0,50 mm, with a minimum length equal or greater than 0,i mm (see figures 1 and 2). 2.8 crack system A combination of two or more cracks, each of which is within 0,50 mm of next crack (see figures 1 and
26、2). 2.9 extent of cracking The magnitudes of the longitudinal and transverse components of a crack or crack system are referred to as “the longitudinal extent of cracking E,“ and “the transverse extent of cracking E,“, respectively (see figure i). NOTE : All hydrogen induced crack systems have longi
27、tudinal and transverse components. 2.10 stepwise crack Crack system in which the transverse component is equal to or greater than 0,l mm. Page 6 EN 10229 : 1998 3 Principle of the method The method consists of exposing test pieces without any applied stress to a corrosive medium for a period of 96 h
28、 followed by evaluation of the test pieces. The corrosive medium is a H2S saturated solution which may be either an acidified sodium chloride solution (test solution A see 4.1) or a synthetic seawater (test solution B see 4.2). Other intermediate solutions may also be agreed between purchaser and su
29、pplier. 4 Test solutions 4.1 Test solution A The acidified sodium chloride solution shall be prepared by dissolving 50 g of sodium chloride (NaCI) and 5 g of glacial acetic acid (CH,COOH) in 945 ml of water. The initial pH shall be 2,7 f Oll before H,S is introduced. 4.2 Test solution B (synthetic s
30、eawater) To prepare 10,O I of synthetic seawater, dissolve 245,34 g of sodium chloride (NaCI) and 40,94 g of anhydrous sodium sulfate (Na,SO,) in 8 I to 9 I of water. Add slowly with vigorous stirring, 200 ml of solution B1 and then 1 O0 ml of solution B2. Dilute to 10,O I with distilled or deionize
31、d water. Adjust the pH to 8,2 f Oll with Oll M sodium hydroxide (NaOH) solution or Oll M hydrochloric acid (HCI) before H,S is introduced (see note). NOTE : Only a few millilitres of NaOH solution should be required. a) Solution B1 The solution shall be prepared by dissolving the indicated amounts o
32、f the following salts in water and dilute to a total volume of 7,O I : Mg Cl, 6 H2O : 3 889,O g (= 555,6 911) CaCI, (anhydrous) : 405,6 g (= 57,Q g/l) SrCI, 6 H20 : 14,8g (= 2,l g/I) The solution shall be stored in well-stoppered glass or other chemically inert material containers for a time not exc
33、eeding 6 months. b) Solution B2 The solution shall be prepared by dissolving the indicated amounts of the following salts in water and dilute to a total volume of 7,O I : KCI 486,2 g (= 69,5 911) NaHCO, 140,7 g (= 20,l 911) KBr 7094 9 (= 10,o 911) BO3H3 lg10 g (= 2,7 g/I) NaF 2,1 g (= 0,3 g/I) Page
34、7 EN 10229: 1998 The solution shall be stored in well-stoppered glass or other chemically inert material containers for a time not exceeding 6 months. 4.3 Volume ratio The ratio of the volume of test solution to the total surface area of the test pieces shall be between 3 ml/cm2 and 6 ml/cm*. 4.4 Re
35、agent purity The purity of the gases shall be 993 % minimum per volume. All chemicals shall be of reagent quality. The water shall be distilled or deionized. NOTE : The conductivity of the water should not normally exceed 5 pS/cm. 5 Apparatus Testing shall be carried out in apparatus which meets the
36、 specific requirements for HIC tests and shall take full account of the safety procedures necessary when using toxic hydrogen sulphide gas. The basic equipment of the apparatus shall include the following : - a test vessel and supports made of chemically inert material such glass or polytetrafluoret
37、hylene (PTFE) ; - equipment to maintain the standard temperature during the test ; - devices to measure gas flow rates ; - a trap to avoid backstreaming of air which could give oxygen contamination of the test atmosphere. This could be, for instance, a vessel with sodium hydroxide solution to bind t
38、he surplus H,S. 6 Test pieces 6.1 Location and orientation 6.1.1 Samples from which the test pieces will be machined shall be removed from the material to be assessed by any appropriate method. If the samples are flame cut, they shall be of sufficient size such that test pieces can be machined well
39、away from the heat affected zones. Page 8 EN 10229 : 1998 6.1.2 Three test pieces shall be prepared from the sample (see 2.1) with the main axis in the longitudinal or in the main deformation direction : a) for welded tubes test pieces shall be taken from weld and in an angle distance of 90“ and 180
40、“ to the weld : b) for seamless tube test pieces shall be circonferentially staggered by 120“ : c) for other product, location and number of test pieces shall be agreed at the time of enquiry and order. 6.1.3 A method shall be used to maintain the identity of the test pieces. This identification sha
41、ll be made at on one or on both small surfaces. 6.2 Size If not otherwise specified, the dimensions of the test pieces shall be as follows : Length L = 100mm i2 mm Width b = 20 mm f 0,5 mm Thickness a = full material thickness less a maximum of 1 mm on each surface for products with nominal thicknes
42、ses from 6 mm up to 30 mm. The thickness of the test piece shall be at least 50 % of the nominal thickness with a maximum of 30 mm. For product with thickness lower than 6 mm or greater than 30 mm the dimensions of test pieces shall be defined at the time of enquiry and order. 6.3 Preparation 6.3.1
43、Mechanical flattening of curved test pieces shall not be permitted. All test pieces shall be pre-machined to final dimensions plus 0,25 mrn on width (b) and thickness (a). The final 0,25 mm shall be removed equally from opposite faces and in stages using a wet wheel surface grinder or equivalent. 6.
44、3.2 The four principal faces of the test pieces shall then be prepared using standard metallographic preparation methods to a final 320 grit finish. 6.3.3 If testing is not to be carried out during the same day the test pieces shall be stored in a dessiccator. It is recommended that storage should n
45、ot exceed 24 h. Page 9 EN 10229 : 1998 7 Test procedure 7.1 Test batch When test pieces are tested in batches, the number of test pieces that make up a test batch shall be limited only by the volume of the test vessel and the solution volume/test piece surface area ratio (see 4.3). 7.2 Degreasing Al
46、l test pieces shall be degreased in a suitable solvent immediately prior to testing. Degreasing shall be considerated as satisfactory if the following test is satisfied : A drop of distilled water, which is placed on the test piece surface after degreasing, must spread out, .e. wet the surface witho
47、ut forming beads. After degreasing, the test piece shall only be handled using degreased tongs or clean gloves. 7.3 Test piece exposure 7.3.1 The test pieces shall be stacked with the faces which were parallel to the original surface of the product vertical in the test vessel, spaced in accordance w
48、ith figure 4 by distancers (made of glass, PTFE or similar material) normally not less than 5 mm apart and 5 mm minimum from the test vessel walls. 7.3.2 The temperature of the test solution shall be maintained at 23 “C f 2 “C for the period of the test. 7.3 3 Testing shall be carried out using one
49、of the test solutions specified in accordance with clause 4. The test solution to be used shall be agreed at the time of enquiry and order. 7.3.4 Care shall be taken to ensure that all joints of the apparatus are gas tight and hence avoid any possible loss of saturation in the test solution or introduction of oxygen. 7.4 De-aeration and saturation 7.4.1 The solution shall be de-areated by purging with nitrogen at a minimum rate of 100 cm3/min per litre of solution, for at least 1 h. 7.4.2 After de-aeration H,S shall be bubbled through the test solution to achieve and mai