THE INGAA FOUNDATION, INC.

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1 THE INGAA FOUNDATION, INC. 10 G Street, NE, Suite 700 Washington, DC (202) FAX (202) INGAA Foundation Workshop Square Bevels and Camber Issues in Double Jointed Pipe June 18, 2008 Purpose The purpose of this workshop was to educate and inform the community about a need for standards and measurements as they relate to double joined pipe. On June 18, 2008 representatives from the INGAA Foundation member companies met in Houston, Texas to discuss this issue. The list of attendees is included in Appendix A. Current Issue In order to save costs associated with welding and coating in the field, the pipeline industry has seen increased use of double jointed pipe or utilized 80 foot joints. Double jointed pipes are lengths of pipe (app. 40 ) that are joined by welding. The pipe is being manufactured to at least API 5L standards and welded in accordance to API 1104 accepted procedures, however due to the worst-case scenario out of square regulations, which allow a 0.2% offset per length of pipe, camber issues of up to 11 inches per 80 feet of pipe are possible. When these crooked pipes are joined and sent for coating, the camber issues cause damage to the coating equipment, affects the quality of the pipe coating application and is a potential safety hazards to coating workers. The double-jointed pipe can also cause transportation difficulties getting to the project site. Figure 1- Diagram of the worst-case scenario, double-joined pipe issue In addition to the technical issues, contractual issues also arise due to this problem. If the pipe is manufactured within the specifications throughout the process, it is difficult to assign fault and costs. The result is additional process delays and resource costs which by some estimates are as high as several hundred thousand dollars. These delays also cause more issues such as delays in service schedules and angry landowners trying to fully utilize their property.

2 Figure 2- A double-jointed pipe with a visible camber issue Potential Causes 1. Pipe Rolling There do not appear to be any camber issues with spiral pipes, however straight seam pipes have repeatedly caused problems. The problem could possibly be attributed to the particular cold expansion method used to expand the pipe. The two methods are: Hydrostatic Expansion- It is observed that hydrostatic cold expansion typically produces a uniform camber with a bias because of the seam weld. Mechanical Expansion- This type of expansion can result in the development of hooked ends, due to the clamping mechanisms. Hooked ends may be causing the camber issues with double joined pipe. Even if a pipe has a hooked end, when considering the entire length of the pipe, it often falls within the present API 5L offset specifications. INGAA Foundation, Inc. 10 G Street, N.E. Suite 700 Washington, D.C (202) FAX (202) www. ingaa.org

3 To address this issue, there is a new API 5L 44 th Edition specification to be implemented in October 2008 that will set a maximum offset of inches within 48 inches of the end of a pipe. For further clarification and illustration, a copy of this specification is given in Appendix B. Figure 3- Flat edge held along a pipe indicating a pending camber issue 2. Cutting Procedures When the bevels on the pipes are cut there is no preference given to seam placement. Additionally, some pipes are cut square to the earth, while other pipes are cut square to the pipe axis. Finally, sometimes both ends of the pipe are cut at once, square to each other, while other times the ends are cut independently. This can result in a randomness of the camber problem. The lack of standard cutting procedure may be contributing to the double jointed camber issues. The double joining facilities make their own bevel before they weld cuts, and are usually done with respect to the pipe axis. This alignment is then checked using a large level or t-square based on the last four feet of pipe. This could be contribute to the camber issues, however the new API 5L 44 th edition specification may solve this problem.

4 Figure 4- An exaggerated look at the different cutting procedures. The image on top is of bevels cut square to the earth, parallel to each other. The image on the bottom is of bevels cut square to the pipe axis. 3. Transportation It was agreed that the handling of the pipe during transportation from the pipe mill probably isn t enough to cause the camber issues. The pipe goes directly from the double joining rack or facility to the coating plant and no transportation of any distance is needed. In the field, camber issues don t pose a problem because pipe is bent for installation anyway and the specifications for the field are less stringent. Possible Solutions 1. Tightened Pipeline Specifications Many companies have proprietary standards for pipes that they are including in their contracts with manufacturers that tighten the camber specifications. Some pipe manufacturers seem to have no issues with specifications tighter than API 5L and are already producing at these company standards, however others may not be willing to manufacturer at specifications other than API 5L for all pipe sizes and wall thicknesses. Some alternative specifications already being utilized include: 0.15% offsets ½ inch offset for 40 feet of pipe 5 / 8 inch offset for 40 feet of pipe No double jointed issues were reported by companies using these specifications. 2. Increased Quality Control INGAA Foundation, Inc. 10 G Street, N.E. Suite 700 Washington, D.C (202) FAX (202) www. ingaa.org

5 While pipes with camber issues still fall within API specifications, coating facilities could potentially identify troublesome pipes and take them out of the racks. However, this poses many problems. It is difficult to take pipes out of the machinery and many facilities don t have a process set up to easily offload the rejected pipe. Increases in rejected pipe will also decrease the amount of pipe available for production which delays deliveries to the job site. Finally, the double joining contractor is not in the business of pipe inspection and this added burden will lead to much higher costs. 3. Coat Pipes Before Double Joining It is possible to coat pipes before double joining, but it would require an extra process and cost to then manually coat the welds either at the welding rack or in the field. 4. Helical Pipe Helical pipe can be manufactured in 80 foot sections and pose no problem to coating machines. The issue with helical pipe is that some of the weld seams are on the bottom of the pipe. However, this may not be an issue as putting the seams on the top quarter of the pipeline may not be applicable anymore for internal corrosion of dry gas pipelines. 5. Stagger Seam Welds approximately 180 degrees to Counter Offsets There are standards that set how close pipe seams can be in order to counter crack propagation between joints. Additionally, pipe seams are not usually placed on the bottom of the pipe, in order to minimize selective seam internal corrosion on wet systems and to better control fracture behavior during a rupture. At least one company has adopted an opposite policy, placing weld seams on the bottom of the pipe to protect against third party damage. Regardless of top or bottom seam placement, staggering seams has not been a solution in the past, however as mentioned above, this may be an out-dated practice given new welding practices and spiral welded pipe. Moving Forward It is important to find a solution to the double jointed pipe camber issues. It s entirely possible that the new API 5L hooked-end standard will solve the issue, however this is not known for certain. Further analysis is needed within the industry to analyze the costs of this issue and the money that would be required to fix the problem. It seems as though some companies have already found some working solutions, however many of the specifications and procedures are proprietary. It was suggested that INGAA collect company cost information and specifications anonymously, so that it can be available to the industry. Further workshops on the issue may also be needed.

6 Appendix A Workshop Attendees Name Company David A. Fisher Labarge Pipe & Steel Company dafisher@labargepipe.com David L. Johnson Panhandle Energy David.Johnson@sug.com David Taylor Transcanada Pipeline david_taylor@transcanada.com Dennis Harwig Edison Welding Institute dharwig@ewi.org Dennis J. Patterson Bi-Con Services Inc. djpatterson@bi-conservices.com Dennis Langston Spectra Energy jdlangston@spectraenergy.com Donald Merchant Williams don.w.merchant@williams.com Frank Smith El Paso Corporation frank.a.smith@elpaso.com Glenn Smotek Bayou Companies glenns@bayoucompanies.com Greg Tencer El Paso Corporation greg.tencer@elpaso.com Harold Kraft Alliance Pipeline harold.kraft@alliance-pipeline.com Humberto Munoz Bayou Companies humbertom@bayoucompanies.com James Nelson Kern River Gas Transmission Company james.nelson@kernrivergas.com James Hickman Centerpoint Energy James.Hickman@centerpointenergy.com Jerry Shaw Williams Jerry.Shaw@Williams.com Jon Barfield El Paso Corporation Jon.Barfield@elpaso.com Kate A. Szilagyi INGAA kszilagyi@ingaa.org Ken McDougall U.S. Pipeline kmcdougall@uspipeline.com Kevin Geroy Gas Transmission Systems kevingeroy@gtsinc.us Jeff Kittka National Fuel Gas kittkaj@natfuel.com Larry W. Christmas Panhandle Energy larry.christmas@sug. com Lee D. Walker El Paso Corporation lee.d.walker@elpaso.com Lisa Beal INGAA lbeal@ingaa.org Mike E. Kress Bayou Companies mikek@bayoucompanies.com Mike Langston Price Gregory International mlangston@pricegregory.com Mike Morgan El Paso Corporation mike.morgan@elpaso.com Mark L. Hereth Process Performance Improvement Consultants mlh@p-pic.com Nadir Sidi INGAA nsidi@ingaa.org Nathan Ames Edison Welding Institute nate_ames@ewi. org Neil Hruzek Commercial Coating Services International neilh@commercialcoating.com Rex Littrell Spectra Energy rclittrell@spectraenergy.com Richard Hoffmann INGAA rhoffmann@ingaa.org Robin Reed Transcanada Pipeline robin_reed@transcanada.com Steve Rapp Spectra Energy scrapp@spectraenergy.com Ted Smith Questar Ted.Smith@Questar.com Terry D. Boss INGAA tboss@ingaa.org Troy L. Ruflin Williams Troy.L.Ruflin@Williams.com Von McAllister Kern River Gas Transmission Company Patrick.McAllister@kernrivergas.com INGAA Foundation, Inc. 10 G Street, N.E. Suite 700 Washington, D.C (202) FAX (202) www. ingaa.org

7 Appendix B- Selection from API Specification 5L/ISO 3183

8 INGAA Foundation, Inc. 10 G Street, N.E. Suite 700 Washington, D.C (202) FAX (202) www. ingaa.org

Guidance for Specification and Purchase of Segmentable Induction Bends and Elbows

Proceedings of the 2012 9th International Pipeline Conference IPC2012 September 24-28, 2012, Calgary, Alberta, Canada IPC2012-90094 Guidance for Specification and Purchase of Segmentable Induction Bends