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Sec~8 8 Repairs, Alterations, and Rerating of Piping Systems 管道系统 维修,改造及重新核定


8 Repairs, Alterations, and Re-rating of Piping Systems 8.1 Repairs and Alterations 8.2 Welding and Hot Tapping 8.3 Re-rating


8.1 Repairs and Alterations


8.1 Repairs and Alterations 维修和改建 8.1.1 General 大纲 由于维修,改造阶段不同于新建, 原则上符合ASME B31.3要求, 而不是实际 根据. 在不能满足ASME B31.3时,管道工程师或授权检验员应遵循API 570 指导来代替按照 ASME B31.3严格要求. The phrase “principles of ASME B31.3” has been employed in API 570, rather than “in accordance with ASME B31.3.”


8.1.2 Authorization 授权 1. 2. 3. 4.

所有维修及改建工程开始前应经检查员授权. 管道改造工作可能有必要事先咨询并通过管道工程师审批 检查员可以指定任何检查点(包括停留点). 在对修护单位能力满意之下,一般例行维修及程序,授权检验员可事先给予 有限的授权.


8.1.2 Authorization 授权 1. 2. 3. 4.

所有维修及改建工程开始前应经检查员授权. 管道改造工作可能有必要事先咨询并通过管道工程师审批 检查员可以指定任何检查点(包括停留点). 在对修护单位能力满意之下,一般例行维修及程序,授权检验员可事先给 予有限的授权


109) Authorization for alteration work to a piping system may be given by the inspector after: a) b) c) d)

Notifying the jurisdiction and getting their approval Consulting API 570 and getting the approval of the owner-user Consultation with and approval by a piping engineer Discussing with and consent by an examiner

110) A repair procedure involving welding requires that the root pass of the weld be inspected before continuing the weld. A "hold" on the repair is required at this point. Who designates this "hold?“ a) b) c) d)

A metallurgist The owner-user An API 570 inspector The welder supervisor


111)What type of repairs and procedures may the inspector give prior general authorization to continue (provided the inspector is satisfied with the competency of the repair organization)? a) b) c) d)

Major repairs and minor procedures Limited or routine repairs and procedures Alterations and re-ratings Minor re-ratings and alterations

112)Who approves all proposed methods of design, execution, materials, welding procedures, examination and testing of in-service piping? a) b) c) d)

The jurisdiction or the piping engineer as appropriate The analyst and the operator as appropriate The examiner and the piping programmer as appropriate The inspector or the piping engineer as appropriate


8.1.3 Approval 正式批准  所有管道维修, 改造建议的方法,应得到授权检验员或管道工程师审批.  运转管道,在线焊接必须的到业主/用户批准.


运转管道, 在线焊接必须的到业主/用户批准


运转管道, 在线焊接必须的到业主/用户批准


8.1.4 Welding Repairs (Including On-stream) 焊接维修(包括运转中管线) 8.1.4.1 Temporary Repairs 临时修理 管道工程师设计 一个分割两半焊接全面包围圈套筒或箱式外壳可施加在损 坏或腐蚀的区域.临时外壳和维修的设计应管道工程师批准. 纵裂纹不能以这种方式进行修复, 除非管道 工程师已确定,纵裂纹不会在围 圈套筒延伸. 在有些情况, 管线工程师有必要咨询断裂分析师


如果局部维修(例如;点蚀或针孔状) 可以运用半圆扣板或钢板,角焊方式罩盖 修复部位. 上述修护方法的前提为;  SMYS < 40 000psi (275 MPa) 最小屈服强度  API Standard 579-1/ASME FFS-1-通过适用性评价 作业要求:  修复版尺寸不能大于管半径  两个修复最小距离间隔为 √(Dt)


纵裂纹不能以这种方式进行修复(半圆弧板或钢板-角焊), 除非管道 工程师 已确定,纵裂纹不会在围圈套筒延伸


All repair and welding procedures for on-stream lines shall conform to API 2201. 运转管道焊接维修应当符合 API 2201要求


分割连接器或补修板 的修补运用前提要求 满足SMYS/FFS 两项要求


Annex C (informative) Examples of RepairsC.1 Repairs 修补

GMAW / SMAW 焊接方法: 当室温小于10oC,焊接ASTM A-53, Grades A and B; A-106, Grades A and B; A-333; A-334; API 5L钢材或等同焊材时应当使用低氢焊条(AWS EXX16 or E-XX18) 在焊接其他低级碳钢材料(在询问工程师下使用) :  如果使用低氢焊条,焊接时母材温度可以低至0oC. 焊接方法:  垂直焊缝-C2,C3 焊接方向应Vertical-up 垂直向上 / 焊条直径≤ 4mm /  横向焊接-C1 焊条≤4.8mm / 焊缝应当有根部衬背. 如受修复的管道已彻 底用超声波的方法检查和具有足够的承受焊接焊弧厚度衬板可以免除.


Used ≤Φ4.8mm, Low Hydrogen electrode.

≤Φ4.8mm, with backing strip.


8.1.4.2 Permanent Repairs 永久修复 如有缺陷, 可以把缺陷完全去除, 按照 8.2 以焊接填充形成的沟槽. 插入修 复板可用于修复损坏或腐蚀的区域,如果满足以下要求:  全熔透坡口焊缝  一类与二类管道修复焊缝必须 100% 射线探伤或超声波测试  修护板可以以任何形状,必须拥有一寸(25mm)半径圆角 . ASME PCC- 2 焊接修理管道系统的更多信息


8.1.5 Non-welding Repairs (On-stream) 非焊修复 局部减薄部分或圆周线缺陷临时修理,可能通过安装适当的设计和应用 非焊外壳(例如螺栓钳,非金属复合管套,金属和环氧树脂包裹,或其他非 焊接的临时修理) 检修期间或其他适当的机会,采取适当的行动把临时修复复原,以恢复原 始的完整的管路系统


8.2 Welding and Hot Tapping 焊接, 热连接


8.2.1 General 所有维修及改装焊接应按照ASME B31.3的原则来进行. 运转管道焊接, 热连接应参考 API 2201 进行. 8.2.2 Procedures, Qualifications, and Records 程序,评定与记录 所有维修及改装焊接应按照ASME B31.3的原则来进行. 焊接工艺,焊工资质应当按照ASME B31.3要求.

Charlie Chong/ Fion Zhang/ He Jungang / Li Xueliang


8.2.3 Preheating and PWHT预热和焊后热处理 8.2.3.1 General 参照API 577指导预热和焊后热处理. 8.2.3.2 Preheating 预热温度用于焊接维修应按照适用的规范的合格的焊接工艺. 临时修理,可以经过管道工程师审批例外. 改装或修理管道系统时预热不低于300oF(150oC)可能被视为替代新建管线 焊接规范焊后热处理要求. 预热不可能用于防止环境开裂


预热不可能用于防止环境开裂. 当使用的预热的替代焊后热处理要求时,需要和管道工程师协商,考 虑 (1) 潜在的环境开裂和 (2) 足够的焊后韧性..


8.2.3.3 PWHT 焊后热处理 焊后热处理应使用管道系统的维修或改装的适用要求如ASME 参考 8.2.2.2 预热作为代替焊后热处理的指导. 局部焊后热处理取代 360o 全面围绕热处理,以下要求应当符合:    

程序经管道工程师开发并得到审核通过, 充分考虑材料,焊接与应力等因素 前期焊接,焊接预热温度至少150oC / (全程) 焊接时保持此温度. 局部焊后热处理覆盖面至不小于两倍管道厚度,按照管道厚度,形状合理 安装至少两个或更多热电偶  热处理受处理区域,受热范围应包含;任何管道分支连接或其它附件,  遵照规范执行,而不是耐环境开裂为目标.


8.2.4 Design 设计 对接接头应为全熔透坡口焊缝. 8.2.5 Materials 母材 在维修或改建所用的材料是质量符合适用的规范已知的,可焊接的材质. 8.2.6 NDE 焊接修护或改装的无损探伤要求验收应按照适用的规范和业主/用户的规格. 表面和内部缺陷NDE检查应按照ASME 锅炉和压力容器 第五节 ASME BPVC Section V


8.2.7 Pressure Testing 压力试验 经过改建和主要维修通常需要压力测试.参考ASME PCC-2 压力测试的更多信息.  当压力测试是没有必要或不实际,无损检测可以用来代替压力测试  无损检测用来代替压力测试必须得到授权检验员/管道工程师的咨询与同意. 当最终闭合焊缝不实际进行的压力试验时,损检测用来代替压力测试必须同时满 足以下条件:  新的或替换的管道通过压力测试(或NDE代替)并按照适用的规范审查,设计,  封闭焊缝必须是全熔透对焊,例外为: Class 150(500oF) 能用滑动式法兰设计/ 承插焊法兰或承插焊活管接(Union)尺寸NPS 2或更少Class 150(500oF) .  最终关闭对焊应为100%RT或角度束超声波探伤,  MT或PT表面探测. 用户应当指明超声横波检验员必须拥有相关的工业超声横波探伤资质.


http://www.pipeliners-uk.com/photo3_10.html


http://www.pipeliners-uk.com/photo3_10.html


8.3 Re-rating 重新评级 重新评级管道系统的通过改变(1) 温度等级或 (2) 最大允许工作压. 必须满足以下要求:    

通过管道工程师或授权检验员计算审核, 重新评价应当符合新建规范要求, 检查记录验证管道系统符合当前工艺,压力要求以及适当的腐蚀预留厚度, 重新评估系统是否应当按照新建规范做管道泄漏测试(除了不带来材料强度 变化的温度更改不需要做管道泄漏测试),

     

泄压装置设置;适当的设定压力,并有相应的排泄能力, 重新评级,被授权检验员或管道工程师接受, 所有的管道系统中的组件符合压力,温度等级, 管道系统有足够的灵活性适应重新评级后的温度变化, 适当的工程记录更新, 实际的冲击试验证明(在规范要求下);最低工作温度达到规范韧性要求.


OPEN


107)When making repairs and alterations to piping systems, the principles of __________ or the code to which the piping system was built shall be followed: (2013 June) a) b) c) d)

ASME B31.3 API 570 API 574 ASME B&PV Code

108)Repair and alteration work must be done by a repair organisation as defined in API 570 and must be authorised by the __________ prior to its commencement: a) b) c) d)

Jurisdiction Inspector Owner-user Examiner


109)Authorisation for alteration work to a piping system may be given by the inspector after: a) b) c) d)

Notifying the jurisdiction and getting their approval Consulting API 570 and getting the approval of the owner-user Consultation with and approval by a piping engineer Discussing with and consent by an examiner

110)A repair procedure involving welding requires that the root pass of the weld be inspected before continuing the weld. A "hold" on the repair is required at this point. Who designates this "hold?â&#x20AC;&#x153; a) b) c) d)

A metallurgist The owner-user An API 570 inspector The welder supervisor


111)What type of repairs and procedures may the inspector give prior general authorisation to continue (provided the inspector is satisfied with the competency of the repair organisaton)? a) b) c) d)

Major repairs and minor procedures Limited or routine repairs and procedures Alterations and re-ratings Minor re-ratings and alterations

112)Who approves all proposed methods of design, execution, materials, welding procedures, examination and testing of in-service piping? a) b) c) d)

The jurisdiction or the piping engineer as appropriate The analyst and the operator as appropriate The examiner and the piping programmer as appropriate The inspector or the piping engineer as appropriate


113) Who must give approval for any on-stream welding? a) b) c) d)

Owner-user Jurisdiction Examiner Analyst

114) An inspector finds a crack in the parent metal of a pipe adjacent to a support lug. The pipe was being inspected after a 5 year run. Before repairing, he should: (2013 June) a) Notify the jurisdiction prior to the start of any repairs b) Write a detailed procedure for the repair organisations use in repairing the crack c) Consult with the piping engineer to identify and correct the cause of the crack. d) Consult with a metallurgist prior to writing a procedure to repair the crack.


115) A full encirclement welded split sleeve designed by a piping engineer may be applied over a damaged or corroded area of a pipe. This is considered a temporary repair. When should a permanent repair be made? a) If the owner-user designates the welded split sleeve as permanent, it may remain. b) A full encirclement welded split sleeve is permanent if okayed by the inspector. c) A full encirclement welded split sleeve is considered a permanent repair. d) A permanent repair must be made at the next available maintenance opportunity.


116) What type of defect, corrosion, pitting and / or discontinuity should not be repaired by a full encirclement welded split sleeve? a) b) c) d)

A longitudinal crack A circumferential crack Pits that are one half through wall General corrosion in the longitudinal direction.


117) If a repair area is localised (for example, pitting or pin-holes) and the specified minimum yield strength (SMYS) of the pipe is not more than __________ psi, a temporary repair may be made by fillet welding a properly designed plate patch over the pitted area: a) b) c) d)

30,000 psi 55,000 psi 40,000 psi 36,000 psi

118) Insert patches (flush patches may be used to repair damaged or corroded areas of pipe if several requirements are met. One of these is that an insert patch (flush patch) may be of any shape but it shall have rounded corners with __________ minimum radii. a) b) c) d)

0.375" 0.50" 0.75" 1"


119)An inspector finds a pin-hole leak in a weld during an on-stream inspection of a piping system. A permissible temporary repair is :a) b) c) d)

The use of plastic steel to seal off the leak Driving a wooden plug into the hole Screwing a self tapping screw into the hole The installation of a properly designed and fabricated bolted leak clamp.

120)Temporary leak sealing and leak dissipating devices shall be removed and the pipe restored to original integrity: a) b) c) d)

As soon as the piping system can be safely removed from service At a turnaround or other appropriate time When the leak seal and leak dissipating device ceases to work As soon as possible â&#x20AC;&#x201C; must be done on a safe, emergency shut-down basis


123)All repair and alteration welding to piping systems shall be done in accordance with the: a) built b) c) d)

Exact procedures of ASME B31.3 or to the code to which it was Standards of ASME B31.1 or the code to which it was built Principles of ASME B31.3 or the code to which it was built Ideals of ASME, NBIC, or API standards

124)Welders and welding procedures used in making piping repairs, etc. shall be qualified in accordance with: a) b) c) d)

ASME B31.3 or the code to which the piping was built NBIC or the system to which the piping was built NACE or the method to which the piping was built ASTM or the law to which the piping was built


125)The repair organisation responsible for welding shall maintain records of welding procedures and welder performance qualifications. These records shall be available to the inspector: a) b) c) d)

At the end of the job After the start of welding Following the start of welding Before the start of welding

126)Preheating to not less than __________ 째F may be considered as an alternative to post weld heat treatment for alterations or repairs of P-1, piping initially post weld heat treated as a code requirement (may not be used if the piping was post weld heat treated due to environmental cracking prevention). a) b) c) d)

150 200 300 350


127)When using local PWHT as a substitute for 360-degree banding on local repairs of PWHT'd piping, which of the following items is NOT considered. a) The application is reviewed, and a procedure is developed by the piping engineer b) The locally PWHT'd area of the pipe must be RT'd or UT'd c) A preheat of 300oF or higher is maintained while welding d) The PWHT is performed for code compliance and not for environmental cracking 128)Piping butt joints shall be: a) b) c) d)

Double spiral fillet welds Single fillet lap welds Double fillet lap welds Full-penetration groove welds


129)When should piping components that need repair be replaced? a) b) c) d)

When enough time remains on a turnaround to allow replacement When repair is likely to be inadequate When the cost of repair is as high as renewal When replacement is preferred by maintenance personnel

130)Fillet welded patches (lap patches) shall be designed by a) b) c) d)

An engineer The inspector The piping engineer The repair organisation


131) Fillet welded lap patches (overlay patches) shall leave: a) b) c) d)

No membrane stresses Right-angle corners Rounded corners Burnished corners

132) Materials used in making welding repairs or alterations __________ be of known weldable quality: a) b) c) d)

May Shall Should Can


133)Acceptance of a welded repair or alteration shall include __________ in accordance with the applicable code and the owner-user's specification, unless otherwise specified in API 570. a) b) c) d)

Nominal Pragmatic Sizing (NPS) NBE Safeguards Nondestructive examination

134)After welding is completed on a repair or alteration, __________ in accordance with API 570 shall be performed if practical and deemed necessary by the inspector. a) b) c) d)

NPS Safety sanctions BE A pressure test


135)When are pressure tests normally required? a) b) c) d)

Pressure tests are normally required after alterations and any repair Pressure tests are normally required after alterations and major repairs Pressure tests are normally required after major and minor repairs Pressure tests are normally required only as specified by the owner-user

136)When a pressure test is not necessary or practical, what shall be utilised in lieu of a pressure test? a) b) c) d)

NPS Nondestructive examination Vacuum visual examination NBE


138) When it is not practical to perform a pressure test of a final closure weld that joins a new or replacement section of piping to an existing system, several requirements shall be satisfied. Which of the following is NOT one of the requirements? a) The closure weld is a full-penetration fillet weld between a weld neck flange and standard piping component or straight sections of pipe of equal diameter and thickness, axially aligned, and or equivalent materials. For design cases up to Class 150 and 500oF, slip-on flanges are acceptable alternates. b) MT or PT shall be performed on the root pass and the completed butt weld. Fillet welds must have PT / MT on the completed weld. c) The new or replacement piping is pressure tested. d) Any final closure butt weld shall be of 100 % radiographic quality; or angle-beam UT may be used, provide the appropriate acceptance criteria is established.


137)Special procedure in place of a pressure test after an alteration or repair may be done only after consultation with :a) b) c) d)

The operators and the repair organisation The inspector and the piping engineer The jurisdiction The examiner and the inspector

139)Which of the following is NOT a requirement for re-rating a piping system by changing the temperature or the MAWP: a) The existing pressure relieving devices are still in place and set as they were originally b) Calculations are performed by the piping engineer or the inspector c) Piping flexibility is adequate for design temperature changes d) A decrease in minimum operating temperature is justified by impact test results, if required by the applicable code.


178)When making a repair utilising a welded full encirclement repair sleeve and the sleeve material is different from the pipe material, you should: a) b) c) d)

Consult the piping engineer Use a weld rod matching the higher strength material Use a weld rod matching the lower strength material Use an alloy weld rod such as Inco-A

179)What type of electrode should be used when welding a full encirclement repair sleeve? a) b) c) d)

Low-hydrogen electrode Low-phosphorous electrode Low-chrome electrode Low-nitrogen electrode


C.1 Repairs Manual welding utilizing the gas metal-arc or shielded metal-arc processes may be used. When the temperature is below 50 째F (10 째C), low-hydrogen electrodes, AWS E-XX16 or E-XX18, shall be used when welding materials conforming to ASTM A-53, Grades A and B; A-106, Grades A and B; A-333; A-334; API 5L; and other similar material. These electrodes should also be used on lower grades of material when the temperature of the material is below 32 째F (0 째C). The piping engineer should be consulted for cases involving different materials.


180)Which of the following welding electrodes is low-hydrogen ? a) b) c) d)

E6010 E7016 E7011 E7014

181)When welding a small repair patch, the diameter of electrodes used should not exceed a) b) c) d)

1/8" 3/16" 5/32" 1/4"



Api570 chapter 8