Valve World Americas - April 2016 19 www.valve-world-americas.net

It takes training and dedication to close the 10% gap seen in flange leakage in meth-ane. CH4 is one of the hardest things to seal because of the size of the molecule.

A good practice that has tremendous help in other industries is good bolting. One of the major failure modes of all failed joints is not achieving proper gasket load during installa-tion. In a study from the FSA 68% of gasket failures were under compression of the gas-ket. The best way to ensure proper compres-sion (gasket load target) per flange is using a calculated torque value. Many maintenance crews are still utilizing “hand” tightening of joints that leaves no clear method of verifying

correct loading. Another part of good bolt-ing practices that is often overlooked is uti-lizing a hardened flat washer under the bolts to increase torque accuracy. A non-smooth surface between the interface between the bottom of the nut and top of the flange can result in inaccurate load transfer with torque resulting in under compression.

The Fluid Sealing Association has played an active role in assisting industry to lower leaks and become more productive while improv-ing the environment. For more good bolting practices refer to the FSA gasketing manual that covers these and other common gasket issues to reduce to total number of failures.

The EPA has estimated that almost 50% of all Methane leaks in the Natural gas system come from 300,000 miles of pipelines in the transportation and distribution sector. A report in 2015 published in Environmental

Science and technology focused on leakage measurements from 45 compressor stations including transmission and storage. The report measured a total of 219 non-com-pressor connections with an average leak rate of 0.2 SCFM (Standard cubic feet per minute). That leak rate prorated for the United States system with a flanged connec-tion every 10 miles (30,000 connectors) and using the cost at @$5 TCF (thousand Cubic Feet), results in a $525 per connector loss or $15,750,000 losses for the industry per year.

After analyzing the data a serious 80/20 rule appears in regards of bad actors. Only 17% of the connections measured are over the average of .2 SCFM (with a leak rate of 0.49 SCFM and the remaining 83% Average leak-age is 0.09 SCFM). Also just the top 10% of these flanges measured average .93 SCFM – account for almost 40% of the entire leakage. Using the $5 TCF, that is $2400 per flange or only 3,000 flanges in the total system account for over $7 million each year in loss product.

The answer to this issue is in the mainte-nance of the pipeline and one of the main ways to solve it is to focus on good practices.

Methane and Pipeline FlangesMethane (CH4) is the second largest greenhouse gas emitted in the United States. In 2013, CH4 accounted for about appr. 10% of all U.S. greenhouse gas emissions from human activities. Methane's lifetime in the atmosphere is much shorter than carbon dioxide (CO2), but CH4 is more efficient at trapping radiation than CO2. Pound for pound, the comparative impact of CH4 on climate change is 25 times greater than CO2 over a 100-year period.

By Ron Frisard, Vice Chair of the Packing Division and the Gaskets Division – Fluid Sealing Association

Best Practices

TRANSMISSION VALVES

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Any pipeline. Any product. Anywhere.Cameron provides complete solutions tailored to customer needs, considering product, environment, region, and budget concerns. Our skilled service team and international distributor network safely support optimal transmission operations with quick access to service technicians, replacement valves, and spare parts. Additionally, we simplify procurement and warranty processes by o� ering complementary actuators, gears, and valve accessories, increasing uptime and productivity.

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About the AuthorRon Frisard graduated from Northeastern University in Boston with a degree in Mechanical Engineering Technology in 1989. Before joining Chesterton, Ron worked for Newport News Shipbuilding designing propulsion systems for aircraft carriers. He has worked for the A.W. Chesterton Company for the last 25 years in all facets of the Mechanical Packing. Ron has held positions in Application Engineering, Research & Development, and Global Training before accepting a position with Global Marketing as a Field Product Manager. He is currently responsible for packing, gasketing, and live loading Marketing and Training. The training is targeted to end users and the global Chesterton sales force on technical knowledge and industry trends. Ron has presented at many conferences including the Electric Power Research Institute (EPRI), the American Society of Mechanical Engineers (ASME), and Valve World in Europe. Ron has also had articles published onpump packing performance and troubleshooting. Ron is active in software development with many programs to his credit and lately has been the driving force in creating the Global Training Portal, an online webcast and information website for the Chesterton global sales force. Ron has been an active member of the Fluid Sealing Association, including Vice Chair of the Packing Division and the Gaskets Division. Ron has also written multiple articles for the FSA on good maintenance practices.