Having been recently involved deeply in this subject, let me give you the long version - bear with me all pipelines, flowlines and risers fabricated in accordance with API 1104 (all welds on API 1104 pipelines, flowlines and risers must be 1 00% radiographed or ultrasonically tested), must be hydrotested in accordance with API 1110 (maybe other codes depending on your location), which in turn refer to ASME B31.4 or 31.8. ASME 31.4 permits a "waiver" of a hydrotest on “tie“tie-in” welds between two sections of piping that have been previously tested in accordance with the code provided that the weld has undergone u ndergone 100% NDT (see Section 437.1.4 (b) Testing Tie ins, ASME B31.4 2002 Edition). Now, if you are talking about about plant piping, very similar. All piping fabricated in accordance accordance with ASME B31.3 must be hydrotested in accordance with ASME B31. The latest edition of B31.3 permits the same waiver of a hydrotest as 31.4 on “Tie“Tie-in” welds between two sections of piping that have been previously tested in accordance with the code. ASME B31.3 only requires 5% random radiography radiography (or UT) on piping in “Normal Fluid Service” (whihc means hydrocarbon service up to 2500 flange rating) You didn't ask, but will throwi throwi n that API RP14E, only recommends 10% radiography on class 150 to 600lb ANSI rated flanges, 20% on 900 to 1500lb ANSI rated flanges and 100% on 2500 and above. Most companies will have a procedure to perform a "golden weld", but at the end of the day it's what we always referred to as a final tie-in and basically you do a 100% RT or UT NDT on the weld in lieu of pressure testing it. Do you think I have recently been involved with these?
Greg Lamberson Consultant - Upstream Energy Website: www.oil-gas-consulting.com
MJCronin (Mechanical)
6 Apr 07 9:29
LBouzid.... There are no ASME recommendations, but there are usually many recommendations from the company PR office.... Always have plenty of room room around the "golden weld" location for for dignitaries, corrupt politicians politicians and evil lawyers, hangers-on and wannabees. Set up a refreshment area... Put up a tent for the press. Give the poor welder a bath and money for new clothes. Contact the local high school marching band..... See page 4 of this link: http://www.bp.com/liveassets/bp_internet/globalbp/globalbp_uk http://www.bp.com/liveassets/bp_internet/ globalbp/globalbp_uk_english/reports_and_ _english/reports_and_ publications/frontiers/STAGING/local_assets/downloads/bpf11p01-05contsnews.pdf And this one... http://azer.com/aiweb/categories/magazine/ai124_folder/124_articles/124_bp_d http://azer.com/aiweb/categories/magazine /ai124_folder/124_articles/124_bp_develop evelop ments.html
-MJC
dcasto (Chemical)
6 Apr 07 14:50
I was at a TRRC seminar on pipeline safety and during the Q&A at the end, someone asked about a repair of a line with a joint of tested pipe and the inspection as prescribed. His question came down to this, how many joints could he install in a row before he needed to a hydrotest? The reponse was great. The head of the commision said, " you could build a 100 mile line from scratch with that technique and we could not stop you. But we'd find 1000 other things to make your life so unbarable you'd wish you would have. (like show me you written policy on the subject and we will hammer it for years)" So there is a question of Generally Accepted Engineering Practices that will come into play and the owners risk assesment. GregLamberson (Petroleum)
7 Apr 07 0:52
Bottom line is, theoretically, you can install a pipeline without a golden weld, but most often the case is, you cannot. Either you have more than 1 test section, you don't for some reason, have flanges on each end, there are a variety of reasons that require a golden weld - they are the norm, not the exception. There is nothing wrong with golden welds and they are allowable by code (see Section 437.1.4 (b) Testing Tie ins, ASME B31.4 2002 Edition).
Greg Lamberson, BS, MBA Consultant - Upstream Energy Website: www.oil-gas-consulting.com
GasGuy (Mechanical)
20 Apr 07 1:02
GregLamberson: You mentioned "The latest edition of B31.3 permits the same waiver of a hydrotest as 31.4 on “Tie-in” welds between two sections of piping that have been previously tested in accordance with the code." I have been unable to find this in B31.3-2004. Could you give me a reference please? GregLamberson (Petroleum)
20 Apr 07 8:11
GasGuy My apologies, I have the 2002 edition, I don't have the 2004 edition, but would be surprised if it did not contain the same provision. In it, section 345.2.3 Special Provisions for Testing states..."The final weld connecting piping systems or components which have been successfully tested in accordance with para. 345 need not be leak tested provided the weld is examined in-process in accordance with para. 344.7 and passes with 100% radiographic examination in accordance with para. 344.5 or 100% ultrasonic examination in accordance with para. 344.6...."
Greg Lamberson, BS, MBA
Consultant - Upstream Energy Website: www.oil-gas-consulting.com
25362 (Chemical)
20 Apr 07 9:59
GregLamberson, not belonging to this engineering field, kindly confirm for my own education whether a "golden weld" means a tie-in that has been 100% radiographed, or 100% U/S inspected, or subjected to a magnetic particle inspection ? GregLamberson (Petroleum)
20 Apr 07 10:34
A golden weld is a weld that has not been included in the hydrotest for a variety of reasons, but has been subjected to complete NDT. We used to refer to these simply as final tie-ins, which is a much more accurate description. There is nothing special nor golden about the welds.
Greg Lamberson, BS, MBA Consultant - Upstream Energy Website: www.oil-gas-consulting.com
Gator (Industrial)
20 Apr 07 23:43
Pasted below (in no particular order) are some relevant comments posted to my PipingDesign group from February this year. I'm not sure if this addition will help. The group is a closed, email-based list, so I can't just post a URL. Paul www.pipingdesign.com
======================================================= Hi Guy's, with regard to the 'Golden Weld' theories going around, the latest bit of info is that such welds are now called 'Closure Welds' as the old term is not representative, in this technically correct world of today. Anyway, being an 'old bod' I will stick to the term for the sake of continuity. In my experience with Golden Welds is that they were always treated with the utmost repect for the obvious reason, that they were not proof tested by going through the hydrotest process. As for the substitue measures that can be taken with such welds, there are many and usually there is a method statement generated and approved by the Client to spell out the process for completing such welds. I have in the past been involved with the witnessing
of such welds and it is usually up to the Welding Engineer to decide on what length to go with these joints, in the past I have had to follow a whole variety of stringent controls to ensure that the welds were carried out in the best possible way. Some of the measures are as follows: 1). A qualified Inspector being present throughout the welding operation to confirm the visual condition of the weld at all stages of completion. 2). A visual inspection of the root of the weld, this was achieved by leaving the final length of root bead open, (100mm), for a visual inspection with a pen light, to ensure defects such as lack of root fusion were not present. 3). Controlled sequential welding was applied to lessen the unnecessary stress that could be put into the weld by not applying such method. 4). The Hot Pass of the weld was sometimes MPI'd or DPI'd, dependant on the pre-heat requirements or the material being welded.(never the root as it is too sensitive an area and it is best to be covered over with the hot pass bead as quickly as possible for added strength). 5). Heat inputs were sometimes taken at certain intervals during welding by the Inspector, as would be during a Weld Procedure Qualification test, using 'Tong testers'/stopwatch/tape measure/calculator, to ensure that the welder was working within the peramaters stipulated in the relevant welding procedure. 6). Joint interpass temperatures would be taken with a digital thermometer at the end of each pass, to ensure that the interpass tempareture was in line with the welding procedure tolerances. 7). Finally, when the 'Golden Weld' was completed there would be a whole range of NDE to complete such as Visual inspection, MPI or DPI, Radiographic AND Ultrasonic Inspection, both prior to and after Post Weld Heat Treatment, (if PWHT was applicable). Still being in the business after 35 years, I look in dispair today when it is notedthat such critical joints are not treated with the same respect today. It is in my book better to be safe than sorry by going the extra yard with the controls, in such critical instances. ======================================================= Speaking from the Inspector standpoint, I might only add one thing.
The processes for treating final closure welds are well spelled out in some construction codes which I would consult for strict compliance purposes. For instance, ASME B31.3 has extensive directions which I have seen often change the decision on whether or not to hydrotest when it is at all possible. As for the golden term...I learn something new everyday! ======================================================= In a new piping fabrication/installation/replacement jobs, generally all the weld joints are hydroteted (along with other NDT methods) in phases. However, sometimes due to some layout/site problems, it is almost impossible to do hydrotest of the final weld joint. We refer that weld joint as golden joint. Generally, Dye penetrant test of root weld, radiographt etc.. is used for quality control of that joint Say, something like a hook-up to an existing line etc.. ======================================================= Golden weld means, InA tie-in work whatever joints were welded at the fabrication shop,Balance weld must be only one joint at site welding.This weldind joint cal be called as golden joint.This joints should be 100% confidence with the all NDT.Welder could be very very experienced man. ======================================================= This must be the modern day replacement for the fabled golden rivet from shipbuilding days. When inspecting a golden weld be sure not to bend over.
unclesyd (Materials)
20 Apr 07 23:57
Gator, You forgot the Golden Spike in RR construction. We have never had any problem with getting the AI to OK NDT tests in lieu of a hydrotest upon completion of the closure weld. Gator (Industrial) See http://en.wikipedia.org/wiki/Golden_rivet, it's referenced there.
21 Apr 07 0:05
