英文版管道安装方案范例.doc

SINOPEC TCCAttachment-method 21.2 Piping installation and construction scheme1.2.1 major construction methods1、 the construction method for metal pipinga、 piping installation and construction proceduresl pipelines prefabrication proceduresConstruction preparationsmaterial take-overpipelines surface rust removingmarkingmeasures check-upmaterial cuttingbevel machiningweld joints inspectioncoupling and alignmentspot weldcheck-up(weld joints preheating) weldingvisual inspectionPWTcheck and inspection (dimension, hardness, NDT) pressure testprotectionidentificationl piping installation procedures on the siteDelivering prefabricated piping spools to the siteinside pipes cleaningtubing and support installationpiping spools coupling and alignment and spot weldcheck (dimension, weld opening) (preheating) weldingvisual inspection(PWT) inspection (dimension, hardness, NDT) inside pipes purgingsystem pressure testcorrosion proof and insulationb、 piping cleaning before constructionl It is necessary to carry out proper surface cleaning of piping regarding specific material and filth conditions, and precautions measures for avoiding environment pollution shall be performed in advance before the cleaning. l For carbon steel and low alloy steel it is necessary to remove the loose scale and eroding by grit blasting. l For stainless steel it is acceptable to remove surface iron matter at first, and therefore cleaning remnant foreign matters by grit blasting. l It is not allowed to share grinding wheels and files for repairing stainless steel or non-ferriferous material and carbon steel material. l Should be there weld slugs or like that impurity left, it is necessary to use steel brush for cleaning, while to use stainless steel wire brush for stainless steel piping. c、 piping cuttingl It is necessary to adopt bevel machine in notching for piping and fittings, while using semi-automated cutting machine for steel plates. l It is necessary to use gauge to check opening angle for steel plates and fittings. Whenever there is different thickness for both coupling plates (between piping and fittings, piping and plates) it is necessary to machine or grind to needed angles based on drawings or standard maps regulations. l For material cutting it is necessary to tailor according to cutting material sizes defined as in figures, while prior supervising unit approval is required when cutting material length is not indicated. l It is necessary to confirm marking before cutting commencement, and it is to adopt crayon or special pens to mark material code when two segments to be cutted, and to mark pipelines serial number, weld joints serial number at once after steel spools cutting. And it is required to remove the incisions and spurs left by steel material cutting, boring and opening using grinding wheel.l It is necessary to use bevel machine or like that machining methods for steel ducts beveling. If there sleeve tubes are required, it is to adopt oxyacetylene torch cutter for opening for carbon steel pipes while using plasma cutter for opening and using angle polisher for grinding afterwards for stainless steel. l For stainless steel sheets, after cutting by power shearing machine or shearing lathe it is necessary to use manual grinding wheel for trimming along cutting edges. d、 piping bendingl When performing pipelines hot bending or cold bending, it is necessary to fill and tamp with fine sand, which shall be high temperature proof silicon sand with proper grade and purity. Yet lead pipes are not allowed to fill with sand. l Normally, the bending radius of piping is bigger than the external radius 3.5 times. l For whatever profile section of piping, the difference between the maximum external radius and the minimum external radius shall not exceed the normal piping external radius -8% when piping is undergoing internal pressure, while shall not exceed 3% when piping is undergoing external pressure. And bended pipelines shall be free of ripples, cracks, overheated and lamination phenomena. e、 support fabrication and installationl It is necessary to fabricate piping support according to dimensions prescribed by design drawings and perform rust removing and primer painting, and keep properly with alloy steel material marks after completing fabrication.l For finished pipelines support, it is necessary to remove weld knurls and slags and adopt grinding wheeling machine for trimming edges when cutting steel plates, shaped steel and piping by cutters. l For finished pipelines racks, it is necessary to identify their designated numbers with visible marks for distinction purpose. l The position of installation point shall be designated as per design drawing or guided by supervising officer for correct installation. Upon the installation attention shall be paid to following issues that whether tightly connected to components or locked up fast joined with pipelines if using clamps. l Upon pressure test and in the process of installation it is necessary to adopt proper protection measures concerning spring devices and etc. special equipment for avoiding enduring overweight load. l U-shaped screw cap shall be locked up as per drawings. l It is necessary to make sure that any obstruction to removable parts resulting in dysfunction is removed. l The orientation, clearance of binding spot and sliding surface shall be in compliance with requirements prescribed in drawings. l It is not allowed to painting such special sliding surfaces as stainless steel plates, graphite plates and etc. fittings. l Upon the installation of anti-violation device and tension resistant support pole spherical surface bearing, the prior confirmation of its properness is needed before welding commencement. l For rigid suspending racks, it is necessary to perform the welding under tight coalition condition. l For rigid support, the supporting surfaces shall be fully touched and clearance is prohibited for assuring weight of supporting pipes. l During pipelines construction process it is necessary to set up temporary support and carry out the construction simultaneously for avoiding concentrating bearing load on certain point and reducing root efficiency resulted from attaching several branch tubes to one pipe, meanwhile it is not allowed to make nozzles of equipment as support or carry out erection standing on nozzles. The branch tubes shall be welded only after detailed drilling, angle shearing and grinding as per branch tubes shearing angles. l Where setting up steel beams for support, it is not allowed to directly assemble by drilling the steel beam that bears main load on the basis of disparate pipelines dimensions and it is necessary to set up according to pipe support position and type as showed in figures. l It is not allowed to secure the pipelines temporary support by spot welding randomly on equipment, pipelines and piping for avoiding causing equipment and pipelines impairment. l It is not allowed to directly secure piping support above expanded iron plates, checkered sheet iron or grid plates, but it is necessary to secure to existing or added girders beneath. l It is necessary to compare every group of supports with drawings for making sure that all components are installed and at proper position including temporary support applying to pressure test. l For all support components with screw threads, it is necessary to check their operability or potential damages and replace the damaged members in time. l For nuts locks and temporary locking accessories of screw components, it is all necessary to check their compliance with prescribed requirements. l It is necessary to adjust orientation of the spring for its load and motion graduations are exposed to easily picked up position, and replace the impaired scales in time, but prior to the replacement, it is needed to mark the correct position of scales to be replaced on the spring shell, so that replaced scales may tally with previous locations. l For designing making use of fluids devices as pipelines positioning, say oil pressure anti-violation device, it is imperative to check degree of tightness and fluids volume, should there fluids be found insufficient, it is needed to inform the supervising units for replenishing. l For certain sliding supports with sliding surfaces being fabricated by graphite, steel or steel to steel, it is imperative to carry out construction as per drawings strictly, and special attention shall be paid to requirements relating to reserved clearance and pre-dislocation. l Upon completing the pressure test, all devices applied to the test, for example locking devices of spring support and temporary supports, shall be removed. l For spring supports, it is needed to check to make sure that the load movement indicator is close to previously designed cold location and pipelines are at correct height. l For supports with positioning devices, say anti-violation device and etc., it is also required the movement indicator. f、 piping installationl Construction of all ground pipelines shall be carried out strictly based on design drawings, the requirements with respect to dimension tolerance are as follows: regarding linear distance the allowed tolerance shall not exceed 3.2mm for pipelines with nominal diameter less than 250mm（including）, while 4.8mm for pipelines with nominal diameter ranging from over 300mm（including）till 900mm.l For seam steel pipes the vertical weld seams must be staggered and keeping away from manifold nozzles. l In the course of coupling and connecting fittings, it is necessary to use spacer plate for the space on welding spotl The opening of weld piping manifold nozzles shall not be less than the internal radius of branch tube joint at connected end, while not bigger than the internal radius 4.8mm.l When prefabricating pipelines, it is needed to reserve 50mm relating to spot welding location for coupling and connecting on the site. l Prior to welding reinforcement plates to steel pipes for branch tubes or pipelines, it is needed to make 1 or 2 6mm openings for the purpose of exhausting and pressure testing during welding. And the reinforcement plates shall tightly joined with steel pipes, the maximum clearance shall not exceed 1.6mm。l The maximum levelness tolerance of pipelines shall not exceed 6.4mm，while the height tolerance for two ends of pipelines shall not be more than 6.4mm。l For piping of pipe racks attention shall be paid to pre-stress shrinking and stretching and it is necessary to carry out welding after shrinking or stretching as per designated securing location in figures, and special attention shall be given to the joint of pipe interface with rack interface. l The pipelines passed heat treatment test shall keep away from flames or arcing. l During the process of pipelines group welding on the site it is required to use crayon or painting pens to mark map number and seal welding joint serial number for easily performing random NDT and installation. l For piping spools finished pre group welding it is needed to mark pipelines serial number as well as blind seal and tightly bind pipes ends using plastic bags (pipe cover). l Prior to pre-welding pipelines on the site it is imperative to remove and clear inside pipes foreign matters, say slag, for assuring inside pipes cleanness. l Prior to the site erection it is necessary to clear rust and other foreign matters from all flanges, should there exist any scratch on interface, it is needed to repair the surface to smooth and even condition. l Prior to installation of valves at the site it is necessary to purge using high-pressure air, and at the beginning of purging it is forbidden to open the valve. After clearing surface, it is to open valve and purge pipe inside and close at once upon completing purging. And it is required to repair rusted and impaired flange surfaces. l There is a requirement for workers to report to technicians at once after they found out that there are air vent pipe, draining pipe and piping with slope not indicated in drawings. l Whenever there is a disagreement between piping assembling and other steel structures, it is forbidden to cut steel structures randomly and a report to design and construction departments shall be required. l When erecting orifice plates attention shall be paid to fluids and fluids orientation, the pressure difference hole shall be upwards if there are gas fluids in pipelines while the hole shall be downward if there are liquid fluids in pipelines. l When connecting shrinkable hoses, it is needed to maintain its flexibility, and shrinking or stretching is forbidden for avoiding impairing its normal functioning. l For cast iron valves and flange valves of big diameter, there is a danger causing valve flanges damage owing to deformation of flange surface and uneven tightness of bolts, so it is necessary to check flange surfaces to be coupled to make sure there is no distortion resulting from improper welding, prior to the installation. l Special attention shall be paid to pipelines to be connected with equipments, there must be proper temporary support for avoiding causing equipment dysfunction, excess deformation, even damage resulting from enduring resistant stress, bending stress and vertical stress.l For piping spools and fittings required internal lining, it is needed to blind seal the both ends upon completing purging pipes. g、 pressure test of pipelinesl Unless otherwise specified, all pipelines to be pressure tested shall be inside purged using clear water prior to the test. l Prior to purging, it is required to segregate parts not to be tested from tested parts for avoiding test water entering equipment inside. l When purging using water, it is needed to improve test water momentum as possible and perform purging by segments. Whenever there are valves, it is better to close valves and open flanges for small foreign matters and iron dross running off flanges and close down flanges after making sure that there are no foreign matters in water.l Prior to purging, measures aiming at protecting instruments within the system shall be took, and orifice plates, nozzles, filtering mesh, throttles and check valves trims shall be removed and kept properly, that shall be restored upon finishing the purging. l The purging using water shall be carried out continually, when there are no designing regulations, the purging test is passed through visual test of compliance of water color and transparency at exit with that of entrance. l Prior to testing, verify the testing package, including checking the extent of test, positions of blocking as well as the use of various kinds of fittings.l For gas medium line, the water weight must not exceed the stress load of supports or the line itself.l For some lines, in case that the design might not consider the pressure test using water and permanent supports cannot endure water weight, adequate temporary supports shall be used. If spring supports are not strong enough to support the water weight, temporary supports must be engaged.l Prior to testing, check whether each testing package is provided with adequate draining facilities and all vents are open.l Prior to testing, check line supports are correctly and firmly fitted with respect of position, material and quantity.l Where the orifice plates may block water or gas following, such orifice plates shall be fitted after testing.l Where the testing package includes flex joints, it is required to verify whether the temporary guide is necessary.l We prefer to use water for pressure test. However, if the use of water may harm the system, we will use gas or other liquid according to design requirements.l The following requirements shall be met for testing of austenitic stainless steel piping systems. No.ItemRequirement1PH682CL-40PPm and below3CL22PPm and below4ferrite content 0.5PPm and below5temperature1640l Piping systems shall be subject to pressure test after fitting. Where equipment is incorporated into the testing package, the test pressure must not be higher than the allowable value to the equipment or its internals, whichever is the smaller.l Pneumatic test shall be applied to vacuum lines. Unless otherwise required by design, the test pressure shall be 0.1Mpa in all cases. l The pressure test special for equipment is performed offsite, so equipment shall be blocked at the nozzles connecting with lines that are to be tested.l Test shall not be carried out in case that the ambient temperature is less than 5.l Pressure gauge to be used in the pressure test shall have been calibrated, with precision not less than Grade 1.5. And it is appropriate that the range of the gauge is the same as the value of test pressure. The gauge may be fitted at low positionthe discharge of pump, or high position but the static hydro pressure shall be considered.l Vents shall be open while water is being charged into line system so as to discharge all air inside piping system. After water overflows the vents, close and lockout the vents. Pressure shall be raised slowly after the system is full of water. While pressure is equal to expected value and remains unchanged, check whether there are leaks on welds, flanges and threaded joints.l During testing, slowly raise the pressure up to a half of the test pressure value (hereafter referred to as TP); after that, the pressure shall go up at a rate of 1/10 of TP every 10 minutes till it is equal to TP. The pressure shall be maintained at TP for 10 minutes during which soap solution is to be spread on welds, flanges and threaded joints for leak check, prior to pressure is released down to the design pressure.h、 Inspection of Piping Workl Ma