«Совершенствование методов повышения эффективности выборочного р. Совершенствование методов повышения эффективности выборочного ремонта магистральных газонефтепроводов
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Приложение А (обязательное) Раздел 1 «Classifications of pipeline defects» Студент: Группа ФИО Подпись Дата 2БМ5А Афанасьев Р. Г. 22.05.17 Консультант кафедры ТХНГ : Должность ФИО Ученая степень, звание Подпись Дата доцент Крец В. Г. к.т.н, доцент 22.05.17 Консультант – лингвист кафедры ИЯ : Должность ФИО Ученая степень, звание Подпись Дата доцент Коротченко Т. В к.ф.н, доцент 22.05.17 Classification of pipeline defects Gas and oil transmission pipelines have a good safety record. This is due to a combination of good design, operating practices and materials. However, like any engineering structure, pipelines do occasionally fail. The major causes of pipeline failures around the world are corrosion and external interference. Therefore, assessment methods are needed to determine the severity of such defects when they are detected in pipelines. Defects occurring during the fabrication of a pipeline are usually assessed against proven and recognized quality control (workmanship) limits. These workmanship limits are somewhat arbitrary, but they have been proven over time 6 Defects of the linear part of main pipelines are subdivided into: defects of pipe; defects of insulating coatings; impermissible welding elements and structural details;; inadmissible adapters. defects that are associated with a change in the design position of pipeline, its stressed state and deformations. Defects of the pipe are divided into two categories on the degree of danger: Defects which are subject to repair (DSR) Defects of prime repair (DPR). The magnitude of the destructive pressure at the level of the test pressure and the geometrical parameters of the defect are taken as a criterion of danger. The defects of the insulation coating according to the degree of danger are regulated by regulatory documents. The minimum value of the transitional insulation R п = 10 3 Om*m 2 .resistance is used as an integral criterion for the limiting state of insulating coatings. Изм. Лист № докум. Подпись Дата Лист 108 Совершенствование методов повышения эффективности выборочного ремонта магистральных газонефтепроводов Разраб . Афанасьев Р. Г. Руковод. Крец В.Г. Консульт. И.о.Зав. Каф. Бурков П. В. Classification of pipeline defects Лит. Листов 124 НИ ТПУ гр. 2БМ5А By the type of pipe damage defects of the pipeline are divided into the defects of the wall of pipe, geometry of pipe and defects of welded seams. Defects of the geometry of pipe — the defects associated with a reduction in the pipeline cross-section due to a change in its shape. They are divided into the following groups: Corrugation — reducing the flow cross section of the pipe, accompanied by transverse alternating convex and concave walls, as a result there is loss of stability on the transverse bend with the fracture of the axis of pipeline. Corrugations on the body of the pipeline are represented in figure 1; Figure 1 — Corrugations on the body of the pipeline 6 L, W — corrugation sizes respectively along forming and on a pipeline circle, h — corrugation top height Dent - local reduction of the pipeline cross-section without a fracture of the axis, caused by a transverse mechanical action. Dent on the body of the pipeline is represented in figure 2; Изм. Лист № докум. Подпись Дата Лист 109 Classification of pipeline defects Figure 2 — Dent on the body of the pipeline 6] L, W — sizes respectively along forming and on a pipeline circle; h — depth of the dent Narrowing (ovality) — reduction of the pipe cross-section with a deviation of the pipe section from the circle. Ovality on the body of the pipeline is represented in figure 3; 0° 180° А-А 270° 90° А D min D n А Figure 3 — Ovality on the body of the pipeline 6 D n , D min — respectively the nominal and the minimum diameter of the pipeline Изм. Лист № докум. Подпись Дата Лист 110 Classification of pipeline defects Defects of pipe wall are the defects which do not change the сross-section of pipes. They are divided into the following groups: Loss of metal (continuous uniform corrosion, continuous uneven corrosion, local pitting corrosion, local spotty corrosion, local ulcerative corrosion, rib corrosion, erosion, dents in the manufacture, nicks, scuffing, flaw) — local reduction in the wall thickness of the pipe as a result of corrosion damage; The loss of metal is divided into united and single. United loss of metal is a group of two or more corrosion defects combined into a single defect when the distance between neighboring defects is less than or equal to the value of the four wall thicknesses of the pipeline in location of defects. United loss of metal is characterized by the overall area determined by the extreme points of defects from the composition of the group. It is equal to multiplication of width of the united defect W of the pipe circumference and the length of the united defect L along the axis of the pipeline. The united loss of metal is represented in figure 4. Defects are grouped according to the parameters in the database "Defect", technical reports on the diagnosis and acts of additional control are designated as "united loss of metal." Figure 4 — United loss of metal and dimensional area 6 Изм. Лист № докум. Подпись Дата Лист 111 Classification of pipeline defects Single loss of metal is a defect of the metal loss when the distance to the next metal loss is greater than the value of four thicknesses of pipe wall in the defect area. Single loss of metal is represented in figure 5. Figure 5 — Loss of the metal 6 L, W — sizes of metal loss respectively along forming and on the pipeline circle, h — depth of the loss of metal; t ost — residual wall thickness of the pipeline Rupture — mechanical damage to the wall of the pipe in the form of deepening with reduction of thickness of the wall of the pipe formed by the solid body moving on the pipe surface. Rupture is represented in figure 6; Изм. Лист № докум. Подпись Дата Лист 112 Classification of pipeline defects Figure 6 — Rupture on the wall of the pipeline 6 L, W — scratches sizes respectively along forming and on the pipeline circle; h — maximum depth of scratches; t ost — residual wall thickness of the pipeline Stratification — internal discontinuity of the pipeline metal in transverse and longitudinal direction, which separates the metal of the pipe wall into layers of technological origin. Stratification is represented in figure 7; Figure 7 — Stratification of the metal of the pipeline wall without reaching the surface 6 Изм. Лист № докум. Подпись Дата Лист 113 Classification of pipeline defects L, W — stratification sizes respectively along forming and on the pipeline circle; h ra — maximum depth of stratification Stratification with the exit to the surface (membrane rolling) — stratification that extends to the inner or outer surface of the pipeline. Stratification with the exit to the surface is represented in figure 8; Figure 8 — Stratification with the exit to the surface 4 L, L 0 — stratification sizes respectively along forming and on the pipeline circle; L B — extent of border of an exit of stratification of metal to the surface of the pipeline; d — maximum depth of the stratification Stratification in the near-weld zone — stratification adjacent to the weld (at a distance from the seam transition line to the base metal to the edge of the stratification is less than or equal to the value of the four wall thicknesses of the pipe). Stratification in the near-weld zone is represented in figure 9; Изм. Лист № докум. Подпись Дата Лист 114 Classification of pipeline defects Figure 9 — Stratification in the near-weld zone 4 L, L 0 — stratification sizes respectively along forming and on the pipeline circle; h — depth of occurrence of the stratification from the outer surface of the pipe wall; L ad — length of the adjunction bundles to the weld seam There is an additional danger associated with the possible presence in the weld of a crack formed during the application of the weld seam under the influence of delamination. Change of wall thickness is gradual thinning of the pipe wall formed in the manufacturing process of sheet metal or pipe. Change of wall thickness is represented in figure 10; Изм. Лист № докум. Подпись Дата Лист 115 Classification of pipeline defects Figure 10 — Change of wall thickness 6 L, W — sizes of change of wall thickness respectively along forming and on the pipeline circle; h — depth of the decrease of thickness; t ost — residual wall thickness of the pipeline Crack — defect in the form of discontinuity of metal, the geometry of which is determined by two dimensions (depth, extent).Crack is represented in figure 11; Figure 11 — Crack in the pipe wall of the pipeline 6 L, W — crack sizes respectively along forming and on the pipeline circle; h — depth of crack Изм. Лист № докум. Подпись Дата Лист 116 Classification of pipeline defects Defect of a welded seam (pore, crack of the weld, undercut, slag inclusion, faulty fusion) — the ring welded seam containing one and more defects: Non-fusion, crack — defects in the form of metal discontinuity along the weld, which according to the data of in-line inspection device (INID), are identified as a "discontinuity of planar type" of a spiral welded, longitudinal, transverse seam. Non-fusion is represented in figure 12; Figure 12 — Non-fusion 6 W — length of the defect in the circumferential direction; h — defect height; Slag inclusions, pores, undercut, deviation of the seam dimensions from the requirements of normative documents, flaking, which according to the INID data are identified as an "anomaly" of a spiral weld, longitudinal, transverse seam. Pores are represented in figure 13; Deviation of the seam dimensions from the requirements of normative documents is represented in figure 14. А А h W А Изм. Лист № докум. Подпись Дата Лист 117 Classification of pipeline defects W А А h Figure 13 — Pores 6 W — length of the defect in the circumferential direction; h — defect height; А А Figure 14 — Deviation of the seam dimensions from the requirements of normative documents 6 Edge displacement — discrepancy of levels of sheets (for longitudinal and spiral seams) in butt welded connections or arrangements of external and internal surfaces of walls of the welded (welded) pipes (for a cross welded seam) which by data the INID is identified as "shift" of a longitudinal, spiral welded, cross seam. Shift of edges is represented in figure 15; Изм. Лист № докум. Подпись Дата Лист 118 Classification of pipeline defects W А А h Figure 15 - Edge displacement 6 W — length of the defect in the circumferential direction; h — Edge offset depth; Angle error- welded butt joint of a pipe to a pipe (with a connecting part, with a coil), in which the longitudinal axis of the tubes are located at an angle of more than 3 degrees to each other. Oblique joint is represented in figure 16; Figure 16 — Angle error 6 α k — angle of displacement of longitudinal pipe axes Variable thickness of the abutting pipes with respect to the wall thickness of more than 1.5 is a defect (with the exception of joints, made according to special technical conditions, with the corresponding entry in the welding log as part of the executive documentation). Variable thickness of the abutting pipes is represented in the figure 17; Изм. Лист № докум. Подпись Дата Лист 119 Classification of pipeline defects W А А t 1 t 2 h=t 2 -t 1 Figure 17 — Variable thickness of the abutting pipes 6 t 1 – Pipe wall thickness No. 1; t 2 – Pipe wall thickness No. 2; The components of the non-industrial production carry to the inadmissible connecting parts: cover, adapters, and tees. Welded elements and unacceptable structural details of the oil pipeline are as follows: Repair structures, under which an increase in the defect parameters was found to be more than 10%; Repair structures not authorized for use by the Leading Document 23.040.00-KTN-011-11 or regulatory documents in force at the time of installation; Covers that touch the pipe wall; Overhead and welded patches of all sizes and types; Overhead parts from pipe parts; Temporary repair structures with the end of the service life specified in the Leading Document 23.040.00-KTN-011-11; Selections of pressure, welding points for contacts of control equipment, lugs, mechanical signaling devices for skipping diagnostic and cleaning tools with the expired service life according in the Leading Document 23.040.00-KTN-011-11; Изм. Лист № докум. Подпись Дата Лист 120 Classification of pipeline defects Welded connections, do not comply with the normative document. The welded elements and structural details, which are not specified in the technical specification for in-pipe diagnostics of the pipeline section, but have been detected by INID, are subjected to additional control and regarded as defects. Based on the results of the additional control, the classification of parts and the maximum period of their operation are established according to the Leading Document 23.040.00-KTN-011-11. By the degree of influence on the bearing capacity of the pipeline, defects are classified as non-hazardous and dangerous. Defects are on-hazardous when the estimated failure pressure of a defective pipe is not lower than the factory test pressure. The operation of the pipeline in the presence of non-hazardous defects is allowed without restrictions on the pumping modes during the inter-inspection period. Dangerous defects include: Defects of geometry located directly on the seams or adjacent to the welds, if their measured depth exceeds 3% of the nominal outer diameter of the pipe; Defects that are dangerous according to the calculation results for static strength (the design pressure of failure of the defective pipe is lower than the factory test pressure); Wall defects associated with the loss of metal, with the residual wall thickness of the pipe at the level of the technically possible minimum limit for measuring the flaw detector. The operation of the pipeline in the presence of hazardous defects is permitted when restrictions on pumping modes are imposed. Dangerous defects are subjected to selective repair in accordance with established methods of repairing. By the criterion of the need for additional control, defects are divided into those requiring and not requiring additional control 6 The choice of methods for repairing defects that do not require additional control is carried out according to the data of in-tube projectiles. Изм. Лист № докум. Подпись Дата Лист 121 Classification of pipeline defects The appointment of repair methods for defects requiring additional control is carried out according to the data of additional control. If necessary, based on the results of additional control by calculation for strength, it is possible to specify the danger of the defect. Изм. Лист № докум. Подпись Дата Лист 122 Classification of pipeline defects ПРИЛОЖЕНИЕ Б Ремонтные конструкции для постоянного ремонта Обозначе ние Ремонтная конструкция, метод ремонта Описание ремонтной конструкции, метода ремонта П1 Композитная муфта, устанавливаемая по композитно-муфтовой технологии (КМТ) П1В Композитная муфта для ремонта вантузов, устанавливаемая по технологии КМТ П1П7 Композитная муфта для ремонта отверстий, патрубков ремонтной конструкции П7, устанавливаемая по технологии КМТ П2 Обжимная приварная муфта с технологическими кольцами П3 Галтельная муфта для ремонта поперечных сварных швов П4 Галтельная муфта с короткой полостью с заполнением антикоррозионной жидкостью для ремонта поперечных сварных швов и «чопиков» с примыканием к поперечному шву 57...219 1000...2000 400 1000...3500 маx 10500 (для составной муфты) П5 Сварная галтельная муфта с технологическими кольцами для ремонта поперечных сварных швов П5У Удлиненная сварная галтельная муфта с технологическими кольцами для ремонта поперечных сварных швов и дефектов в стенке трубы, примыкающих к поперечному сварному шву и расположенных в зоне шириной до (0,75D н -100 мм) в каждую сторону от поперечного сварного шва Удлиненная галтельная муфта для ремонта гофр с заполнением антикоррозионной жидкостью П8 Муфтовый тройник для ремонта вантузов, сигнализаторов пропуска средств очистки и диагностики, отборов давления, патрубков, отверстий П9 Разрезной тройник заводского изготовления (патрубок приварен к полумуфте тройника в заводских условиях) для ремонта патрубков, отверстий 1 450 3 7 3 7 |