管道施工规范(ASMI).doc

C O N T E N T S PAGE1.GENERAL1.1Scope31.2Specific Job Requirements31.3Codes and Standards31.4Related Engineering Specifications31.5Units32. GENERAL REQUIREMENT2.1Qualification42.2Material43.FABRICATION3.1General53.2Cutting53.3End Preparation63.4Alignment and Trimming73.5General Requirement for Welding113.6Welding Rods113.7Welding123.8Marking203.9Storing204.ASSEMBLING AND ERECTION4.1General214.2Flanged Joint224.3Threaded Joint224.4Mechanical Joint226. INSPECTION, EXAMINATION AND TESTING6.1 Extent of Inspection, Examination and Testing 6.2 Non-Destructive Examination 28 7. PRESSURE TESTING-PROCESS8. COATONG AND WRAPPING OF PIPING 9. CLEANING AFTER PIPING ASSEMBLING AND ERECTION 311.GENERAL1.1ScopeThis procedure covers the general requirements for the piping construction work, including test and inspection of plant to be carried out by China National Chemical Engineer NO.7 Construction Company Ltd (hereinafter referred to as CC-7).1.2Specific Job RequirementsSpecific job requirements which are attached to this procedure cover modifications to this specification, Customers special or local requirements as well as specific job data pertinent to this specification. Where Specific Job Requirements are in contradiction to this specification, Specific Job Requirements shall govern.1.3Codes and StandardsInternational codes and standards supplementary in related to this specification shall be as follows:(1)ASME B31.3 Process Piping(2)ANSI/ASME B1.20.1 Pipe Threads, General Purpose (Inch)(3)ASME/ANSI B16.5 Pipe Flanges and Flanged Fittings(4) ASME Boiler and Pressure Vessel Code, Section V(5) Section II part C Material Specifications-Welding Rods, Electrodes and Filler Metals(6) Section IX Qualification Standard for Welding and Brazing Procedures, Welders, Brazers, and Welding and Brazing operators1.4Related Engineering SpecificationsThe related BASF-YPC Company Ltd. Specification to supplement this specification are as follows:(1) RPI 94/1 General Requirements for BASF Technology Projects(2) 40-010-00-0-0-00-003 Positive Material Identification(3) 50-010-00-0-0-00-003 Piping Material Specification(4) 50-010-00-0-0-00-004 Steam Tracing & Winterization(5) 50-010-00-0-0-00-006 Piping Identification System(6) 50-010-00-0-0-00-009 Pressure Testing-Process & Utility Piping (7) 50-010-00-0-0-00-024 Welding and Non-Destructive Examinations of Piping Systems (8) 50-010-00-0-0-00-025 Shop and Field Fabrication ,Installation and Handling-Process and utility Piping (9) 50-010-00-0-0-00-034 Pipe Support 1.5UnitsThe AA/AE Unit shall be applied as the measurement system for documents and drawings. Nominal size of piping components shall be measured in Inches, for which the abbreviation is NPS. Nominal flange rating shall be as per the applied codes and standards.2.GENERAL REQUIREMENT2.1Qualification(1)Persons who are engaged for welding including tack welding and support welding work shall have passed the welding performance qualification test before commencement of welding works and shall be performed in accordance with ASMEB31.3para.328.(2)Welding Procedure Specification and the Procedure Qualification Record shall be approved by TEC and owner before commencement of welding work. Production welding shall not commence before receipt of written approval and authorization to start welding.(3)Persons who are engaged for pipe-fitting, assembling, erection work, shall be fully trained and shall have the qualification of Employer.License, certificate, pass or qualification issued from Authorities, if available, shall be effective.(4)The inspector nominated for the job must be a specialist or an expert in respective examinations and licensed or qualified by an internationally recognized Association and/or by any statutory requirement applicable.2.2Material2.2.1Piping Materials shall be in accordance with DOC.No.50.010.AA.0.0.00.5012.2.2It is applicable to use other alternate materials which shall be approved by TEC and owner.2.2.3Selection of welding rod shall be in accordance with Welding Procedure Qualification test Record (PQR) unless otherwise approved by TEC and owner.2.2.4Quality certificate of technical gas to be used for the work such as argon gas, propane gas, etc. shall be provided with approval of TEC before work starts.3.FABRICATION3.1General3.1.1Fabrication requirement shall be in accordance with ASME B31.3 unless otherwise specified.3.1.2Fabrication shall be executed in accordance with the related Engineering Specification and the drawings, document stated in Par. 1.4 and 2.3 of this specification.3.1.3The bolt holes of flanges shall be located symmetrically from a vertical center line in a horizontal pipe line, and from plant north in a vertical pipe line unless otherwise indicated in the drawing.3.1.4Marking of piping materials shall be in accordance with Para.10,0 in Doc.No.50.010.00.0.0.00.0253.2Cutting3.2.1Cutting line shall be marked on pipe. Where the material marking will become invisible after cutting, additional material marking shall be provided.3.2.2In the case of gas cutting, cutting surface shall be ground off to remove any edge and roughness and be made flush and smooth so as not to harm welding quality. 3.2.3In the case of gas cutting, cutting slug sticked inside pipe shall be completely removed, especially for boring of pipe for weld branch.3.3End Preparation3.3.1End preparation for butt weld shall be in accordance with Table 3.3.1, or any other which meets the WPS.(1)Welding Bevels for Butt WeldsTable 3.3.1Unit: mmThickness of PipeType of EndShape of Groovett 22Double-V10 2.51.6 0.819 2t37.5 2.5(2) Shape of beveling other than mentioned in Table 3.3.1 shall be in accordance with the WPS approved by TEC and owner. .3.4Alignment and Trimming3.4.1Root gap for butt-weld shall be in accordance with the WPS.3.4.2In the case of butt welding pipe and/or fitting having unequal wall thickness, of which the difference is more than 3 mm in outer surface and/or 1.5 mm in inner surface, the end of the thicker pipe shall be trimmed by grinding as per the Fig. 3.4.2 (a), (b) and (c) shown below. The gradient of this trimming shall be less than 30 between worked and unworked parts shown as below.Unit: mm Over 2 or 0.5 x tm (a) Whichever is lesswhichwhichever is lessMax. 30 tm1.5 or Over tmMax. 30(b)1.5 or Overtm or Over In case ultrasonictest to be appliedMax. 30 tm(c)tm :required minimum wall thickness of pipe.Fig. 3.4.2Note:In the case that “Special End Detail” is specified in the Specification H-103 for the pipe and/or fitting of which the nominal wall thickness is 30 mm and over, the end preparation shall be in accordance with such provision.3.4.3Branch connections which abut the outside surface of the run pipe shall be contoured for groove welds which meet the WPS requirements see Fig. 3.4.3 (a) and (b).Branch connection which are inserted through a run opening shall be inserted at least as far as the inside surface of the run pipe at all points see Fig. 3.4.3 (c).gmmgg0 mm - 3 mm(a)(b)(c)_Tb_Tb_Tbg=Root gap per WPS_m=The lesser of 3.2 mm or 0.5TbFig. 3.4.33.4.4 When a pipe having a longitudinal weld seam is used in a horizontal line, the pipe shall be laid so that the longitudinal weld seam is not on bottom or top of the pipe. (These should be located at least 45o from the bottoms of the pipe).Allocation and relation among circumferential, longitudinal and other (branch, support, etc.) welds are shown in the Fig. 3.4.4 (a), (b) or (c).(1) Circumferential jointL1L2L1C.LC.L Note : L1 100mm L2 50mm or 6 x Tw which is greater Tw: Pipe Wall thickness Fig. 3.4.4 (a)(2) Branch pipe and weld line on run pipeLLL1Fig. 3.4.4 (b)Notes:1.L and L1 show the distance between both toes of the bead.2.L shall be three times the pipe thickness or over.3.L1 shall be more than 100mm.(3)Support/Shoe and weld seam of main pipeDetail “A”“A”When a support is welded to a bend or pipe, the weld shall not cross the weld of the bend or pipe. Both sides shall be roundly welded.LLWelding SupportWelding ShoeLLNote : L shall be minimum 6 mm.Fig. 3.4.4 (c)“A”3.6General Requirement for Welding3.6.1Requirement and criteria for welding shall be as follows, unless otherwise specified in the drawings:(1)Welding shall be performed in accordance with WPS. (2) Welding shall not be carried out in adverse weather conditions where there is impingement of rain, snow, sleet storm or excessive wind at the working area, unless appropriate and adequate protection is provided.(3) The level shall be fully cleaned so that there is no rust, oil, paint, sand, moisture, etc. remaining. Where a bevel is not to be welded immediately it shall be protected to prevent contamination.(4) All slag, weld spatter and flux remaining on any bead of welding shall be removed before the next bead is deposited.(5)Spatter, slag, etc. on the weld or in the heat affected zone, shall be thoroughly removed to the metal surface.(6)Arc strikes on base metal shall be avoided at all times. Arc strike shall be ground flush and liquid penetrant tested. Any defect shall be ground out and weld repaired.(7)Material of wire brush shall be properly selected for working carbon steel respectively. They shall always be kept separate and never used on anything other than the designation.(8)Welding for a welded joint valve shall be carried out with the valve opened.(9)Weld internal protrusion at the weld neck joint of an orifice flange, shall be removed flush and smooth with a grinder. Any concavity in the root, shall be weld repaired and ground flush and smooth. (10)All welds including socket welding shall be performed at least 2 layers weld and end point of weld at each layer shall be changed (stagger). (11)Welding of dissimilar metals shall be carried out at fabrication shop if possible.3.7Welding Rods3.7.1Brand name of welding rod to be used at shop and site shall be approved by TEC and owner before work starts and that shall be used only.3.7.2 Each welder shall be immedatory provided with a portable dryer to shop/Field work after withdrow electrode from main oven container.3.7.3 Baking and Holding temperature of electrode shall be performed with manufactures recommendation.3.8Welding3.8.1Tack welding shall be carried out as follows:(1)Both root and bridge tack welding method may be applied.(2)Avoid wrong fit-up which would cause residual stress.(3)Keep the correct root gap by using spacers according to WPS.(4)Welding condition of tack welding shall be in accordance with WPS.(5)Provide sufficient external pipe clamps or internal spiders for setting up.(6)Ensure the contact surface of the clamps or spiders are made of the same base metal, or an inert compound.(7)Bridge tack shall never be hammered off. Bridge tacks shall be removed by grinding or gas cutting. Gas cutting shall only be performed at the upper part of the weld toe and flush surface of base metal by grinding, and then a liquid penetrant examination shall be carried out. Any defect shall be ground out and weld repaired. 3.8.2Butt joint welding of pipes shall be performed as follows:(1)Welding shall be performed in accordance with WPS.(2)Circumferential butt welding shall be performed without the use of a backing ring unless specified in WPS.(3)Before welding of the root, both ends of the root tack weld bead shall be prepared with a grinder as shown in the following illustration in order to make complete fusion. L1: Max 15mm for NPS 24” Max 40mm for NPS24”Fig. 3.8.23.8.3Branch connections shall be made by using the fittings as specified in the Doc.No.50.010.AA.0.0.00.501.However, where the branch is to be welded directly to the main run in accordance with Doc.No.50.010.AA.0.0.00.501.or Piping Arrangement Drawing, welding shall be performed, unless otherwise specified, shown in following Fig. 3.8.3:Tm*_Th 6 mm _0.5 Tr_ThThe surface of the weld metalshall be finished flush by grinding or drilling. 2 NPS 1 1/2 NPS 3 mmTmBranch Pipe Size* :Specified as per WPS_Th_Th_Tb_Th_Th_Tb_Tb_Tb_Tb(2)(1)(3)(4)(5) OutletAtc*_Tr3 - 5 f Vent hole 45tc* _0.5 Tr3 - 5 f Vent holeA_Trtc*Unit: mm*tc 4545351.6 - 3.2Fig. 3.8.3Notes:1.Throat thickness “tc” shall be of 0.7Tb (minimum 6.4 mm).2. The symbols used in these figures are as follows:_Th: nominal thickness of run pipe_Tb: nominal thickness of branch pipe_Tr: nominal thickness of reinforcement pad3.At first, weld part and prepare the weld surface with a grinder, then weld the part .4. Where reinforcement is necessary, it is indicated in the Piping Arrangement Drawing and Notes for Piping Drawings.3.8.4Fillet welding of pipe to slip-on and socket weld flanges shall be performed as shown in following Fig. 1.4 T min.Fig. 3.8.4Unit: mmconcentrically set1.4 T min.Any weld metal into the bore of the pipe shall be removed by grinding or filing to make it flush with the inside diameter.1.4 T min.3.01.4 T min.TTt(a) Slip-on(b) Slip-onT1.6 - 3.2t(c) Socket Weld1.4 T min.3.01.4 T min.TTNotes:1.T: thickness of pipet : thickness of flange hub2.If 1.4 T is larger than t, t shall be taken.3.8.5Socket welding of pipe components other than flanges shall be performed as shown in following Fig. 3.8.5:Fig. 3.8.5T = nominal wall thickness1.6 - 3.2cxTcx (min.) = 1.25T but notless than 3.2 mmUnit: mmcx 3.11Marking3.11.1All piping components for which welding has been completed shall bear the painted marking with the identification symbol of the welder as confirmation.3.11.2Spool piece No. shall be clearly marked on fabricated components.3.12StoringInside of fabricated components shall be cleaned by air blowing, then openings of fabricated components shall be covered with suitable materials so as not to enter the foreign matters such as sand, mad, etc. into piping components. Gasket surface of flange, thread, welding bevel shall be protected from any damage due to cleaning work and handling of storing.4.ASSEMBLING AND ERECTION4.1General4.1.1Before assembling of piping, actual tolerance causing from foundation, steel structure, equipment installation work shall be considered for the piping assembling work.4.1.2Excessive stress shall not be allowed to the nozzles of rotating machine when the flange of fabricated component is connected, such work shall be carried out in the presence of person in charge of the mechanical work. And openings such as flanged joints of a pump, compressor, etc. shall be kept covered with thin metal plate or other solid blinds with a handle to prevent dust and/or foreign material from entering into the machine.4.1.3If hot work to be performed in the vicinity of instrument control or power cable duct, an adequate protective cover shall be provided in advance so as not to damage the cables.4.1.4When work is carried out in the vicinity of piping made of, or lined with special materials such as plastics, rubber, glass, etc., care shall be taken so as not to damage them.4.1.5Valves shall be assembl