eeJB4708-2000钢制压力容器焊接工艺评定EN.doc

中华人民共和国行业标准中华人民共和国行业标准 Industrial Standard of the People s Republic of China JB 4708 2000 JB T 4709 2000 JB 4744 2000 钢钢制制压压力力容容器器焊焊接接工工艺艺评评定定 钢钢制制压压力力容容器器焊焊接接规规程程 钢钢制制压压力力容容器器产产品品焊焊接接试试板板 的的力力学学性性能能检检验验 Welding procedure qualification for steel pressure vessels Welding specification for steel pressure vessels Mechanical property tests of product welded test coupons for steel pressure vessels Issuance 15 08 2000Implementation 01 10 2000 Issued Jointly byThe State Bureau of Industry 本英文版为内部资料 仅供参考 以中文 版为准 The Chinese version of standards has precedence to their English translations which are only for internal reference The State Bureau of Petroleum and Chemical Industry Notice for the Issuance of Four Industrial Standards such as Welding Procedure Qualification for Steel Pressure Vessels etc No SMIB 2000 401 All sectors involved This is to notify that in accordance with the Approval Procedures of Pressure Vessel s Industrial Standards as stipulated by the State Quality if the welding seam widths in both sides are equal then the face whose surface covering welding seam is first finished is the front face 3 13 Root bend The bend because of the tensile surface of the test piece is the reverse side of the welding seam 3 14 Side bend The bend because of the tensile surface of the test piece is the transverse section of the welding seam 4 General principles 4 1 The welding procedure qualification should be based on reliable steel welding properties and finished before welding products 4 2 The general process of welding procedure qualification is drawing up the welding procedure instruction welding test pieces and manufacturing test samples inspecting test pieces and samples measuring if welded joints have the required utility properties submitting welding procedure qualification record and evaluating the welding procedure instruction The welding procedure qualification verifies the correctness of welding procedure drawn up by the welding unit and judges its capability 4 3 For the T type joints and angle joints whose cross section have been welded all but their interior defects can not be detected and the manufacturing unit has no capability to ensure the welding throughout then the modeling test piece should be manufactured for welding procedure qualification and the welding shall be allowed only after affirmation by dissection test 4 4 The equipment and instruments for welding procedure qualification have to be in normal operating condition steels and welding materials have to be conformed to the relevant standards the unit s skillful welder can operate the unit s welding equipment to weld test pieces 5 Welding procedure qualification regulations for butt and fillet welding seam 5 1 The butt welding test piece should be adopted when carrying out the butt welding procedure qualification The qualified butt welding procedure is suitable for the fillet welding seam When evaluating the welding procedure of no pressure fillet welding seam the fillet welding test pieces can be only adopted The test pieces shapes are showed in figure 1 a The plate butt welding test piece b The pipe butt welding test piece 1 The butt welding test pieces a The plate fillet welding test piece b The plate and pipe fillet welding test piece 2 The fillet welding test pieces Figure 1 The test pieces shapes for welding procedure qualification 5 1 1 The qualified welding procedure of the plate butt welding test pieces is applicable to the pipe butt welding seam and vice versa 5 1 2 The qualified welding procedure of the plate and pipe fillet welding test pieces is applicable to the plate fillet welding seam and vice versa 5 2 The welding procedure elements are divided into the important factor additional factor and minor factor 5 2 1 The important factor refers to the welding procedure factors which may affect welded joints tensile strength and bend strength 5 2 2 The additional factors refer to the welding procedure factors which may affect welded joints impact toughness If the impact test is stipulated the additional factors have to be added 5 2 3 The minor factors refer to the welding procedure factors that have no marked influence on the stipulated mechanical properties 5 3 Qualification regulations 5 3 1 The welding method 5 3 1 1 Re qualification is indispensable if changing the welding method 5 3 1 2 the important additional and minor factors of the welding procedure qualification for various kinds of welding methods see table 1 a When changing any important factor it is necessary to evaluate the welding procedure qualification again b When adding or changing any additional factor the test pieces for additional impacting toughness have to be tested according to the added or changed additional factors c When changing minor factors re qualification of the welding procedure qualification is unnecessary but the welding procedure instruction should be drafted again 5 3 1 3 The same seam can be qualified separately according to each welding method or welding procedure when it is welded by adopting the two or more welding methods or by the welding procedure which has different important and additional factors and it can also be qualified comprehensively by adopting the two or more welding methods welding procedures and welding pieces When being applied to the weldment after comprehensive qualification qualification one or more welding methods welding procedure can be adopted but their important and additional factors should be remained unchanging according to the relevant regulations for each welding method or welding procedure determines the effective range is suitable for weldment thickness 5 3 2 Base metals The standard shall class for the base metals classification and groups according to the chemical composition mechanical properties and welding properties see table 2 5 3 2 1 Grouping regulations a When the important and additional factors remain unchanged the qualified welding procedure of one grade base metal may be suitable for the other grade base metals in the same group b The qualification for the base metals in group VI 2 is suitable for the base metals in group II 1 c In the same classification number the qualification for base metals with higher group number is suitable for the welded joints made of the base metals in this group and the base metals with lower group number d Apart from the circumferences that is regulated in b and c if there is change in base metals group number there have to have a re qualification 5 3 2 2 Classification qualification regulations For welded joints made from base metals with different classification even if each base metal has been qualified re qualification for the welded joints is necessary But the qualification of the II classification or VI 1 VI 2 group base metal with the same steel grade is suitable for the welded joints from the same classification or the same group base metal and the I classification base metal 5 3 2 3 Qualification regulations of the steel grades not including in table 2 a The grade of steel included in National Standards or Industrial Standards should be classified into their corresponding classifications and groups or into new classifications and groups according to their chemical composition mechanical properties and welding properties And the welding procedure qualification should be carried out for the steel grades that are not included in National Standards or Industrial Standards b For the foreign steels the welding procedure qualification should be carried out to each steel grade named as its National standard regulation on its first application If its welding properties have been known and its chemical composition mechanical properties are equivalent to that of one steel grade in table 2 and the welding procedure qualification for that steel code has been finished then the welding procedure qualification for this foreign steel can be exempted It can be classified into the classification and group of that steel grade in the unit s technology documents 5 3 3 Post welding heat treatment 5 3 3 1 Classifications of the post welding heat treatment 5 3 3 1 1 The base metals with classification No VII is divided into a Do not carry out post welding heat treatment b Carrying out the solid solution treatment or stabilization heat treatment after welding 5 3 3 1 2 The base metals except classification No VII are divided into a Do not carry out post welding heat treatment b Carrying out post welding heat treatment when temperature is lower than the lower transformation temperature c Carrying out the post welding heat treatment when temperature is higher than the upper transformation temperature for example normalizing d Carrying out the post welding heat treatment firstly in temperature higher than the upper transformation temperature then in temperature lower than the lower transformation temperature e g tempering after normalizing or quenching e Carrying out the post welding heat treatment between the upper and lower transformation temperature 5 3 3 2 Welding procedure re qualification is necessary if changing the kind of post welding heat treatment 5 3 3 3 When the impact test is specified The welding procedure qualification is needed if changing the range of temperature and the time of the post welding heat treatment But the gas welding is the exception The post welding heat treatment of the test pieces should be generally same as that of the welded pieces in the manufacture the heating temperature of test pieces should not violate the regulations of the corresponding standards or technology documents When carrying out the post welding heat treatment with the temperature below the lower transformation temperature the test pieces holding time should be no less than 80 of the welding pieces amounted holding time during its manufacturing process 5 3 4 Test pieces thickness and welding pieces thickness The effective extent of welding pieces thickness for which the qualified welding procedure of butt welding test pieces is suitable following the regulations of table 3 and 4 if the base metals of the test pieces are in IV 2 group and the strength type low alloy steel whose lower limit of the standard tensile strength are larger than 540 MPa Others the steels should follow the regulation of table 5 and 6 5 3 4 1 For the electric arc welding of welding rod submerged arc welding gas tungsten arc welding and gas metal arc welding if the impact test is specified for welding pieces in the case of T 8mm the minimum of the effective extent of the welding pieces base metals thickness after test pieces had been assessed as qualification should all be 0 75T it would be treated according to the original regulations if the test pieces have been processed by post welding heat treatment in temperature above the upper transformation temperature or the austenite base metals have been processed by solid solution treatment after welding 5 3 4 2 If the welding pieces are within the circumference of table 7 the maximum of the effective extent of welding pieces base metals thickness should follow the regulations in table 7 after test pieces had been assessed as qualification Table 3 The regulation on the test pieces base metals thickness and welding pieces base metals thickness mm The effective extent suitable for welding pieces base metals thicknessThe test pieces base metals thickness TMinimumMaximum T 1 5T2 T 1 5 T 81 52 T and no thicker than 12 T 80 75 T1 5 T Table 4 The regulations on the test pieces welding seam metals thickness and welding pieces welding seam metals thickness mm The effective extent suitable for welding pieces welding seam metal thickness The test pieces welding seam metals thickness t MinimumMaximum t 1 5No limitation2 t 1 5 t 8No limitation2t No thicker than 12 t 8No limitation1 5 t Note t represents thickness of the welded welding seam metal by the same welding method or welding procedure Table 5 The regulation on the test pieces thickness and welding pieces thickness carrying out the test pieces mechanical properties test and transverse bending test mm The effective extent suitable for welding pieces base metals thickness The effective extent suitable for welding pieces welding seam metal thickness The test pieces base metal s thickness T MinimumMaximumMinimumMaximum 1 5T2 TNo limitation2t 1 5 T 101 52 TNo limitation2t 10 T 3852 TNo limitation2t 385200 No limitation 2t t 20 385200 No limitation200 t 20 Limited to multi run welding of welding rod electric arc welding submerged arc welding gas tungsten arc welding and gas metal arc welding Table 6 The regulation on the test pieces thickness and welding pieces thickness carrying out the test pieces mechanical properties test and longitudinal bending test mm The effective extent suitable for welding pieces base metals thickness The effective extent suitable for welding pieces welding seam metal thickness The test pieces base metal s thickness T MinimumMaximumMinimumMaximum 1052TNo limitation2t Table 7 the test pieces thickness and the regulation on welding pieces thickness in special condition mm The effective extent suitable for welding pieces base metals thickness The serial No The welding pieces condition The test pieces base metals thickness MinimumMaximum 1When the welding rod electric arc welding submerged arc welding gas tungsten arc welding and gas metal arc welding are used as the root welding it can be assessed singularly at the moment 13 Qualified according to the qualification results of others welding procedures for welding seams continual filling 2The part butt welding pieces which were welded 38 No limitation 3Repairing welding make up welding 38 No limitation No specifying the impact test for the base metal whose classification is VII 6 The base metal s thickness of the thicker edge No limitation 4 The unequal thickness butt welding test pieces should be assessed by the equal thickness butt welding test pieces Except the base metal whose classification is VII 38 The base metal s thickness of the thicker edge No limitation According to the test pieces or welding pieces condition following the corresponding regulations in tables 3 5 6 and article 5 3 4 1 5 3 4 3 If the test pieces conform to the welding conditions in table 8 the maximum thickness suitable for welding pieces after test pieces have been assessed as qualification are specified in table 8 Table 8 Regulations on the test pieces thickness and welding pieces thickness in special welding condition mm The maximum thickness suitable for welding pieces The serial No The test pieces welding condition Base metalWelding seam metal 1Except gas welding the test pieces being processed by post welding heat treatment over the upper transformation temperature 1 1T 2When test pieces are single run or multi run welding if the thickness of any one of its welding bead is thicker than 13mm 1 1T 3Gas weldingT 4Electroslag welding1 1T 5When the test pieces thickness is thicker than 150mm and adopting multi run welding of welding rod electric arc welding submerged arc welding gas tungsten arc welding and gas metal arc welding except the short circuited transition 1 33 T1 33t 6When the test pieces thickness is thinner than 13mm and adopting gas metal arc welding with short circuited transition 1 1T 7When the test pieces welding seam metal s thickness is thinner than 13mm and adopting gas metal arc welding with short circuited transition 1 1t According to the test pieces or welding pieces condition following the corresponding regulations in tables 4 5 6 and article 5 3 4 1 5 3 4 4 There is no limitation on the welding pieces thickness effective extent when the qualified welding procedure for butt welding test pieces is applied to the fillet welding pieces There is no limitation on the welding pieces thickness effective extent when the qualified welding procedure for fillet welding test pieces is applied to the non pressure fillet welding pieces 5 3 4 5 After finishing the compound qualification the effective extent of the welding pieces base metal s thickness should be determined by single welding methods or welding procedure qualification 6 Welding procedure qualification regulations for corrosion resisting bead welding 6 1 Re qualification is indispensable if changing the bead welding method 6 2 If the thickness of the test pieces base layer T is less than 25mm the qualified welding procedure is suitable for welding pieces whose base layer s thickness T is no less than T or equal to T If the test pieces thickness T is no less than 25mm the qualified welding procedure is suitable for welding pieces whose base layer s thickness is no less than or equal to 25mm too 6 3 The welding conditions for re qualification of the corrosion resisting bead welding see table 9 Table 9 Welding conditions for re qualification of the corrosion resisting bead welding ClassificationThe bead welding conditions Gas welding Welding rod electric arc welding Submerged arc welding Gas metal arc welding Gas tungsten arc welding Electroslag welding The bead welding layer s thickness The bead welding layer s thickness is thinner than the qualified minimum thickness Changing the classification of the base layer s metal Base metal The thickness of the base layer steel is beyond the regulation of 6 2 Changing welding rod s specifications only considering the later two digits of its classification Changing welding rod s diameter when carrying our the first layer bead welding Adding or canceling additional filler metal Changing the steel grade of the welding wire or steel strip Changing the welding flux s specification or the mixing proportion of the mixing welding flux Filler metal Changing the solid welding wire to the shielded cored welding wire or vice versa ClassificationThe bead welding conditions Gas welding Welding rod electric arc welding Submerged arc welding Gas metal arc welding Gas tungsten arc welding Electroslag welding Welding position Exc