1、RCC-M-Edition 2007 SECTION IV WELDING_WELDINGSECTION IV DESIGN AND CONSTRUCTION RULESFOR MECHANICAL COMPONENTS OF PWRNUCLEAR ISLANDSRCC-MRCC-M - Edition 2007 Section IV - S S 1000 GENERAL S 1100 GENERAL PROVISIONS S 1110 PRELIMINARY VERIFICATIONS, QUALIFICATIONS AND ACCEPTANCES The use of any weldin
2、g procedures shall be preceded by the following verifications, qualifications and acceptance tests: - preliminary verification of the weldability of the materials (see S 1200), - acceptance testing of lots of filler materials (see S 2000), - qualification of the welding procedure (see S 3000), - qua
3、lification of welders and operators for that welding procedure (see S 4000), - qualification of filler materials covered by the terms of S 5000 (see S 5000), - qualification of the workshop (see S 6000). The main points at which the qualifications specified in the various chapters of this section ov
4、erlap are summarized below. - No lot of filler material may be accepted until a technical qualification data sheet has been issued for the material in question if it is covered by the terms of S 5000. This technical qualification data sheet defines the scope of a lot and also defines the conditions
5、for use of the material. - Any lot of filler material used when a welding procedure is qualified shall have been accepted in accordance with the terms of S 3143. - Welders or operators who have passed the qualification tests welding procedure shall be qualified to use that procedure within the limit
6、s set by the terms of chapter S 4000. Another welder or operator may apply the welding procedure if he has passed the qualification tests in accordance with the terms of S 4000. - The qualification of a welding procedure exempts the filler material used from the standard assembly test stipulated in
7、S 5131.3. The procedure qualification report shall take the place of the welding procedure qualification record stipulated in S 5143. n 113-2007 S 1000 / 1 RCC-M - Edition 2007 Section IV - S A change in brand or manufacturing process of a filler material need not invalidate the qualification of the
8、 welding procedure if the conditions of the paragraph dealing with the area of validity of the qualification of filler materials (S 3215, S 3315, S 3415, S 3615, S 3815), are satisfied. They do however require the requalification of the filler material in accordance with the terms of S 5000. - The q
9、ualification of a welding procedure shall have been approved at the workshop where the procedure is used. Transfer from one workshop to another or to the site shall, however, be allowed subject to the conditions laid down in S 6000. - The tests or standard test coupons required for the qualification
10、 of filler materials covered by S 5000 shall be performed by a qualification fabricating workshop in accordance with S 6000 using filler materials acceptance-tested in accordance with S 2000. Note: Hardfacing by fusion on steel is dealt with separately in chapter S 8000. S 1120 WELDING DATA PACKAGE
11、Each welding data package relates to one component. It is required for pressure retaining components and for reactor internals. It shall comprise: - an overall or outline drawing of the component, marking the position of all welded joints. In the special case of pipelines, other than those of the pr
12、imary loops, to which the concept of an overall or outline drawing does not apply, it shall be possible to identify the type of joint used, e.g. on the isometric drawings, - For components other than piping, a test coupon schedule showing the test coupon and welding sequences for the parts of the co
13、mponent, together with the interlocking stress-relieving heat treatments and inspections, - a catalogue of all joints: for each welded joint, or for each type of joint in the case of piping, the following shall be provided or specified: . a dimensional sketch, . the welding procedure or procedures u
14、sed and the relevant welding procedure data sheets, . the cumulated heat treatments, . the properly referenced qualification test coupon or test coupons which validate the welding procedure, . a recapitulatory list of qualification test coupons for the whole component with, for each test coupon, the
15、 welding procedure data sheet from which the area of validity of the qualification is derived, . a list of welding control test coupons. S 1000 / 2 n 113-2007 RCC-M - Edition 2007 Section IV - S S 1121 WELDING PROCEDURE DATA SHEETS Welding procedure data sheets enumerate and quantify all the variabl
16、es regarded as affecting the area of validity of the qualification of the procedure concerned. In the special case of mixed or heterogeneous welds (see S 3110), the welding procedure data sheet shall specify the provisions adopted (at weld edges or in the standard part of the weld) concerning overla
17、pping of passes or layers and the measures taken to ensure that overlapping is properly performed. S 1200 WELDABILITY OF MATERIALS The Contractor for the main primary system and the Manufacturer for the other components shall satisfy themselves that all the materials to be assembled by means of weld
18、ed joints are suitable for welding by the proposed procedures. The reference is provided by a covered-electrode manual butt weld of significant thickness made in the flat position; the use of other welding procedures constitutes an extension of the weldability of the material. The weldability of a s
19、teel increases with the range of possible choices of welding processes and filler materials and with the widening range of variables of the welding procedures which can be used to make satisfactory welds. The Contractor or the Manufacturer shall make use of test results already available for the mat
20、erials involved or shall, if necessary, carry out adequate additional tests. The information so obtained shall cover both the heat-affected zone and the deposited metal in their final state, that is, they shall take into account the effect of any heat treatment(s) applied after welding. The informat
21、ion shall cover the following aspects of the intended application: - metallurgical characteristics, - mechanical properties: . strength, . toughness (energy absorbed by breakage on Charpy impact test specimen, etc.), - resistance to various types of cracking: . hot, . when reheated, . cold. In parti
22、cular, mixed or heterogenous welds (cladding and buttering comprising stainless steel or Ni-Cr-Fe alloy, repairs included) shall be performed in accordance with the same conditions (preheating, postheating, etc.) as those adopted for welding with a deposited metal the same as the base metal, unless
23、justification can be provided for not doing so. This applies to the deposition of at least all of the layers capable of affecting the base metal above critical temperature AC1; - service performance. n 113-2007 S 1000 / 3 RCC-M - Edition 2007 Section IV - S The scope of this last item depends on all
24、 the various stresses applied to the joint in question (mechanical, thermal and corrosion stresses). In particular, the effects of radiation on irradiated joints and the effect of the environment on all joints shall be assessed. All data proving weldability shall be attached to the part or product q
25、ualification report in compliance with M 140 in order to supplement these reports with regard to weldability as required by M 143.4 and the note of M 143.6. S 1300 GENERAL REMARKS ON HEAT TREATMENTS S 1310 INTRODUCTION The heat treatment parameters set out in subchapter S 1300 are recommended minimu
26、m values; it is understood, that working on the basis of these values, it shall be for the Manufacturer to apply stricter standards, if necessary, in order to ensure the proper quality of fabrication and he shall be able to support by test results his choice of the heat treatment parameters associat
27、ed with the welding operations. The conditions governing the application of such treatments are specified in S 7500. The equivalent thicknesses E to be taken into account for pre and post heating operations are as follows, depending on the type of connection: S 1000 / 4 n 113-2007 RCC-M - Edition 20
28、07 Section IV - S S 1320 PREHEAT AND INTERPASS TEMPERATURE DEFINITIONS The preheat temperature is the minimum temperature in the groove immediately prior to welding or, in case of multi-pass welds, the lowest temperature of the underlying metal immediately before each pass. Interpass temperature sha
29、ll be the highest temperature of the underlying metal immediately prior to each pass. The preheat condition and the maximum interpass temperature shall be defined by the Manufaturer, mainly by reference to: - the grades and thicknesses of the materials to be assembled, - the type of joints, the test
30、 coupon restraint conditions and the welding sequences, - the welding procedures used. The minimum preheat temperature shall be determined on the basis of tests (1) so as to eliminate or minimize the hardening effects associated with phase changes by reducing the cooling rate of the weld. This prehe
31、at temperature shall be maintained over the whole welded joint until heat treatment after welding (postheating or stress relieving heat treatment). The maximum interpass temperature shall be defined on the basis of tests (2) so that the specified mechanical properties of the deposited metal are not
32、affected. (1) These tests form part of the weldability file which includes for example 1st pass hardness measurements and cracking tests. (2) These tests may for example be acceptance or qualification tests for filler materials in accordance with S 2000 or S 5000. S 1321 CARBON STEELS For equivalent
33、 thicknesses E (as defined in S 1310) greater than 40 mm, preheating to a minimum temperature of 100C is recommended, or mandatory if required in B, C or D 4000, for steels of minimum specified tensile strength Rmlower than 440 MPa in the non-stress relieved condition, e.g. steels: S 235 - S 275 P 2
34、35 GH (A 37) P 265 GH (A 42). For steels of minimum specified tensile strength Rmgreater or equal than 440 MPa in the non-stress relieved condition, e.g. steels S 355, P 295 GH (A 48) and P 355 GH (A 52), the minimum recommended, or mandatory if required in B, C or D 4000 preheating temperature for
35、equivalent thicknesses E (as defined in S 1310) equal to or greater than 20 mm, is 125C. S 1322 LOW ALLOY STEELS EXCEPT Cr AND Cr-Mo STEELS CONTAINING NOT LESS THAN 0.5% Cr - 0.5% Mo For equivalent thicknesses E (as defined in S 1310) greater than 15 mm or of specified tensile strength greater than
36、450 MPa, preheating to a minimum temperature of 125C is recommended or mandatory if required in B, C or D 4000. n 113-2007 S 1000 / 5 RCC-M - Edition 2007 Section IV - S S 1323 Cr AND Cr-Mo STEELS For equivalent thicknesses E (as defined in S 1310) greater than 15 mm or of specified tensile strength
37、 greater than 400 MPa, preheating to a temperature between 150C and 300C is recommended or mandatory if required in B, C or D 4000. S 1330 POSTHEATING The purpose of this treatment is mainly to diffuse the hydrogen and to avoid the risk of cold cracking. When preheating is required in accordance wit
38、h S 1320, postheating is then required at a temperature equal to or greater than the preheating temperature for a minimum of 60 min, except if stress-relieving heat treatment is to be performed immediately after welding without any return to room temperature. S 1340 STRESS RELIEVING HEAT TREATMENT T
39、he Manufacturer shall define the conditions for intermediate and final postweld stress relieving heat treatment, if any, in accordance with the requirements of chapter F 8000. Conditions for such heat treatment are dependent on the variables listed in F 8120 and on the welding process used. The curr
40、ently accepted holding temperatures and the times for which they are maintained (the temperature being assumed to be uniform within the range specified throughout thickness of the welded joint) and the minimum thicknesses for which the type of treatment is required are given below for information pu
41、rposes. S 1341 CARBON STEELS Thicknesses over 30 mm (the thickness refers to the parts to be welded; for welds between two parts of different thickness, the thickness of the thicker part shall be used), this limitation can be increased to 35 mm for steels with a minimum specified tensile strength Rm
42、lower than 440 MPa in the non-stress relieved condition, e.g. steels: S 235 - S 275 P 235 GH (A 37) P 265 GH (A 42). - Holding temperature: 550C to 625C (recommended minimum 575C). - Holding time: . 2 minutes per millimetre of thickness (as defined in S 7544 c) with a minimum of 30 minutes and a max
43、imum of 120 minutes. S 1000 / 6 n 113-2007 RCC-M - Edition 2007 Section IV - S S 1342 LOW-ALLOY STEELS WITH THE EXCEPTION OF Cr AND Cr-Mo STEELS - Thicknesses over 10 mm (the thickness refers to the parts to be welded; for welds between two parts of different thickness, the thickness of the thicker
44、part shall be used) with the exception of steels with a nickel content 1%. - Holding temperature: 595C to 675C. - Holding time: . 1 hour per 25 mm of thickness (as defined in S 7544 c) with a minimum of 30 minutes: beyond 2 hours it shall be held for 2 hours + (15 minutes per 25 mm over 50 mm). S 13
45、43 LOW-ALLOY Cr AND Cr-Mo STEELS MARTENSITIC AND FERRITIC STAINLESS STEELS a) 0.5% Cr - 0.5% Mo 1% Cr - 0.5% Mo 1.25% Cr - 0.5% Mo - Holding temperature: 595C to 675C. - Holding time: 1 hour for each 25 mm of thickness with a minimum of 30 minutes; beyond 5 hours it shall he held for 5 hours + (15 m
46、inutes for each 25 mm of thickness over 125 mm). b) Castings of 13% Cr - 4% Ni steel: see S 1343.a. with the following remark: - holding temperature: 595C to 620C. :remark following with the1343.a. S seesteels stainless cMartensitiMo%5.0Cr%5Mo%1Cr%25.2)c?- holding temperature: 675C to 760C. d) Ferri
47、tic stainless steels: see S 1343a. with the following remark: - holding temperature 700C to 760C. S 1400 CONSERVATION OF TEST SPECIMENS, QUALIFICATION ASSEMBLIES AND PRODUCTION WELD TEST COUPONS Discard from test coupons and test specimens of welding procedure qualification shall be kept by the Manu
48、facturer during 3 years. Discard from production weld test coupons and test specimens shall be kept by the Manufacturer until the component is accepted. n 113-2007 S 1000 / 7 RCC-M - Edition 2007 Section IV - S S 1500 DEFINITION OF WELDING PROCEDURE OPERATIONS A welding process is said to be manual
49、if the welding torch or electrode is hand-guided by the welder. A welding process is said to be partially mechanized if the operator can intervene during the course of welding. A completely mechanized, automatic or robotized welding process is one in which no human intervention is possible during the course of the welding operation. S 1600 TO S 1800 NOT USED S 1900 CONTINUED VALIDITY OF QUALIFICATIONS TRANSITIONAL PROVISIONS Subject to compliance with
