GB/T 13401-2017 PDF English


Search result: GB/T 13401-2017_English: PDF (GB/T13401-2017)
Standard IDUSDBUY PDFLead-DaysStandard Title (Description)Status
GB/T 13401-2017315 Add to Cart Auto, < 3 mins Steel buttwelding pipe fittings -- Technical specification Valid
GB/T 13401-2005949 Add to Cart 6 days Steel plate butt-welding pipe fittings Valid
GB/T 13401-1992839 Add to Cart 6 days Steel plate butt-welding pipe fittings Obsolete

GB/T13401-2017 (GBT13401-2017): PDF in English

GB/T 13401-2017 GB NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA ICS 23.040.60 J 15 Partially replacing GB/T 12459-2005, GB/T 13401-2005 Steel buttwelding pipe fittings - Technical specification ISSUED ON: FEBRUARY 28, 2017 IMPLEMENTED ON: SEPTEMBER 01, 2017 Issued by: General Administration of Quality Supervision, Inspection and Quarantine; Standardization Administration of the People's Republic of China. Table of Contents Foreword ... 3  1 Scope ... 5  2 Normative references ... 5  3 Order content ... 6  4 Materials ... 7  5 Manufacturing ... 8  6 Heat treatment ... 12  7 Inspection and testing ... 14  8 Welding repair ... 23  9 Surface protection and packaging ... 24  10 Product quality certificate ... 24  Annex A (normative) ... 26  Additional requirements ... 26  Annex B (informative) Raw materials to manufacture pipe fittings ... 28  Steel buttwelding pipe fittings - Technical specification 1 Scope This Standard specifies technical requirements such as order content, materials, manufacturing, heat treatment, inspection and testing, welding repair, surface protection and packaging, and product quality certificate for steel buttwelding pipe fittings (hereinafter referred to as pipe fittings). This Standard is applicable to pipe fittings specified in GB/T 12459. Other pipe fittings may refer to this Standard for use. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB 150.4-2011, Pressure Vessels - Part 4: Fabrication, inspection and testing, and acceptance GB/T 222, Method of sampling steel for determination of chemical composition and permissible variations for product analysis GB/T 223 (all parts), Iron, steel and alloy - Chemical analysis methods GB/T 228.1, Metallic materials - Tensile testing - Part 1: Method of test at room temperature GB/T 229, Metallic Materials - Charpy Pendulum Impact Test Method GB/T 2975, Steel and Steel Products - Location and Preparation of Test Pieces for Mechanical Testing GB/T 4334, Corrosion of metals and alloys - Test methods for intergranular corrosion of stainless steels GB/T 4336, Carbon and low-alloy steel - Determination of multi-element contents - Spark discharge atomic emission spectrometric method (routine method) b) Material level of pipe fittings (see 4.2); c) Nominal size (standard or designated; when the outer diameter is selected as GB/T 12459 series II, it shall be marked "-II"), nominal wall thickness (see 4.2.2 of GB/T 12459-2017); d) Structure, seamless or welded (if not specified, the fitting manufacturer can choose any kind); e) Product standard number, GB/T 12459 and GB/T 13401 (including version number); f) Number of pieces; g) Required additional requirements (see Annex A) or supplementary requirements. 4 Materials 4.1 The raw materials for manufacturing pipe fittings include seamless pipes, straight seam electrofusion welded pipes, plates, bars and forgings. The chemical composition shall meet the requirements of Table 1. The pipe fitting manufacturer shall conduct chemical composition analysis of the raw materials used according to the melting furnace number. Analysis method is according to GB/T 223 or GB/T 4336, GB/T 11170, to ensure that it meets the requirements of Table 1. The allowable deviation of chemical composition analysis of the finished product shall meet the requirements of GB/T 222. 4.2 The contents represented by pipe fitting material level codes are as follows: a) CF is the abbreviation of carbon steel fitting, that is, carbon steel pipe fitting. The following number is the minimum tensile strength of pipe fitting. The letter K in the suffix represents that the level must be guaranteed to pass the impact test at 20°C. b) AF is the abbreviation of alloy steel fitting, that is, alloy steel pipe fitting. The following figures use characteristic figures familiar in the industry. The letter G in the suffix indicates that the level has higher tensile properties. c) LF is the abbreviation of low temperature steel fitting, that is, low temperature steel pipe fitting. The following number is the minimum tensile strength of the pipe fitting. The suffix letters K1, K2, K3 and K4 represent the lowest operating temperature at -20°C, -46°C, -100°C and -196°C respectively. d) SF is the abbreviation of stainless steel fitting, that is, stainless steel pipe 6.3 When the following conditions are met, heat treatment is not necessary: a) Carbon steel pipe fittings (excluding carbon steel pipe fittings in low- temperature steel) that thermoforming and final forming temperature is between 700°C~980°C and are placed in still air and cooled; b) Forged carbon steel pipe fittings (excluding carbon steel pipe fittings in low-temperature steel) that are less than or equal to DN100, the final forming temperature is between 700°C~980°C and are placed in still air and cooled; c) Pipe fittings manufactured by direct cutting using raw materials that have been heat treated before exiting the factory. 6.4 For carbon steel welded pipe fittings with a nominal wall thickness greater than 19mm and welded after thermoforming (excluding carbon steel pipe fittings in low-temperature steel), if the requirements of 6.3a) are met, it can adopt post- weld stress relief heat treatment. 6.5 For carbon steel welded pipe fittings with a nominal wall thickness less than or equal to 19mm and welded after thermoforming (excluding carbon steel pipe fittings in low-temperature steel), if the requirements of 6.3a) are met, after negotiation between the supplier and the purchaser, it may not conduct thermoforming. However, the suffix letters -NH shall be added after the delivery document and the material level of pipe fittings marked by physical object, such as CF415K-NH. 6.6 For austenitic stainless steel pipe fittings, after negotiation between the supplier and the purchaser, thermoforming is not required. However, the suffix letters -NH shall be added after the delivery document and the material level of pipe fittings marked by physical object, such as SF304-NH. 6.7 The heat treatment furnace shall be equipped with an automatic temperature measuring and recording device. A complete record can be obtained. The effective heating zone of the heat treatment furnace is measured according to the regulations of GB/T 9452. The temperature uniformity of the effective heating zone is ±14°C. 7 Inspection and testing 7.1 Mechanical properties 7.1.1 Sample of mechanical properties 7.1.1.1 The sample shall be prepared from the pipe that has been heat treated (or is formed without heat treatment). It can also be obtained from the sample inspection piece by piece according to NB/T 47013.4 or relevant specifications. Level I is conforming. 7.3.3 In addition to the provisions of 7.3.5, when the weld of the welded pipe fitting is completed by the pipe fitting manufacturer, the full length of welds of welded pipe fittings shall be inspected according to NB/T 47013.2 or relevant specifications. Level II is conforming (excluding stud end manufactured in the method in 5.6). 7.3.4 In addition to the provisions of 7.3.5, for welded pipe fittings made of straight seam welded pipes, if the weld has been 100% radiographically inspected by the welded pipe manufacturer and conforming for level II, the welds of pipe fittings can no longer be inspected by radiography, unless otherwise required. If the weld of the welded pipe is not 100% radiographically inspected by the welded pipe manufacturer, then the full length of the weld of welded pipe fittings shall be inspected according to NB/T 47013.2 or relevant specifications. Level II is conforming. 7.3.5 For welded pipe fittings that do not require weld radiographic testing, after negotiation between the supplier and the purchaser, the radiographic testing is not required for the welds. However, the suffix letters -NX shall be added after the delivery document and the material level of pipe fittings marked by physical object, such as CF370-NX. 7.3.6 In addition to the above regulations, non-destructive testing can be carried out according to the content negotiated by the supplier and the purchaser. For example, magnetic powder, penetration and ultrasonic testing required separately. 7.3.7 Operators engaged in non-destructive testing shall pass the test according to TSG Z8001 or related standards and obtain corresponding qualifications. 7.4 Metallographic inspection Each batch of austenitic-ferritic duplex stainless steel pipe fittings shall undergo a metallographic inspection. Inspection method is according to GB/T 13305. The metallographic structure of pipe fittings in delivery state shall be austenite and ferrite. The austenite content shall be 40%~60%. For welded pipe fittings, the austenite content in the weld area is negotiated between the supplier and the purchaser. 7.5 Hydrostatic test This Standard does not require a separate hydraulic test for pipe fittings. All pipe fittings shall be able to withstand the hydraulic test pressure required by the applicable piping code for seamless pipes with the same nominal size and c) The length is not more than 1/8 of the nominal diameter. 8.2 Before welding repair, defects shall be removed by cutting, shoveling or grinding. According to the material, carry out magnetic particle testing or penetration testing on the removed part, so as to ensure complete removal of defects. 8.3 During welding repair, welding consumables that match the base metal shall be selected. The welder who has obtained the corresponding welding qualification shall perform welding in accordance with the welding procedure specification. 8.4 After weldin.......
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