In chemical processing, gasketed pipe flanges are crucial to preventing leaks, spills and fugitive emissions. It is critical that reliable fasteners are used to maintain the integrity of the joints. However, when a chemical plant in Alabama was experiencing hazardous leaks approximately every two weeks at a particular flange, it discovered that improperly tensioned bolts were to blame.
"Improper tension can lead to premature bolt failure and, in this case, expensive and dangerous leaks," said Jay Palmer, technical sales and engineering adviser at Valley Forge & Bolt. "Using a fastener that can measure clamp load from within the bolted joint can help determine why the improper tension is occurring and assist with solving the problem."
Engineers at the chemical plant reached out to Valley Forge & Bolt to provide a solution to the bolting issue. Valley Forge engineers studied the application and recommended the company's proprietary Maxbolt
The solution worked because -- unlike conventional fasteners -- Maxbolts have a built-in gauge, easily visible on the end of each bolt, that senses and displays clamp load of the bolted joint. Accurate to within +/- 5 percent, the gauge allows plant managers and maintenance staff to easily read joint tension at any time. This vital ability to constantly measure the tension helped prove to the plant's personnel why the previous bolts had been falling out of tension and then validated the long-term solution.
The plant's team installed the 48 Valley Forge Maxbolts on the problematic gasketed pipe flange. The unit was placed into service for 48 hours, then shut down for inspection. "The Maxbolts displayed the residual clamp load and indicated it was dramatically lower than the installed load," said Palmer. "This showed the customer that, a mere two days after installation, bolts were already in need of retorquing."
Staff at the chemical plant retorqued the studs to the original tension. As a result of the proper installation and the staff 's ability to easily see when retorquing was needed, the flange has been in operation for one year with no recurrence of leakage. The case demonstrated that using the correct fastener for the application, made the right way, can solve even chronic leaks.
Valley Forge & Bolt manufactures patented bolting products for critical applications. Products are widely trusted for their unrivaled quality, extraordinary performance and enduring reliability.
For more information, visit www.vfbolts.com or call (800) 832-6587.