By Bret Halley, Chief Operating Officer
The process of mating a bolt and nut together in tension has a long history, there have been plenty of changes in design and standardizations, but in tightening – most bolts still get torqued in some fashion. From centuries old wooden manufactured bolts and nuts hand fitted together, to modern day alloys made to many standards, most problems dealt with in the fastener applications are not developing or maintaining the design load in the torqueing process.
When analyzed, the manufacturing process controls, all the various bolting standards, material selection and design of equipment – the engineering level is detailed, documented and quite effective. Fastener installation however, relying on measurement of twisting force rather than equipment design load being achieved, does affect equipment reliability in our world today. Valley Forge has seen application after application improve with some form of design load verification. Application which have used our MaxBolt™ or SPC4™ Load Indicating fasteners, have data logged and enjoyed an added benefit of real time joint loading. Knowing what load is present in the fastener, or entire joint, no matter what tensioning system is used to install, increases product reliability, speed of installation and safety. Inspection of load rather than torque is attained in seconds with some load indicating systems. The International Fastener Institute (www.indfast.org) equates “nearly 95% of fastener failures are the result of poor fastener selection or improper installation”. With technology changing in the last couple of decades, torqueing or wondering if a fastener is loaded to design, is “old school” compared to engineered products on the market in the 21st century.
Valley Forge & Bolt’s history in supporting customers has driven us into ways we can inspect for load rather than just installing to a torque value. Not only do we think tightening fasteners to a verified load is the best way to solve problems for customers, we are building the future with being able to supply customers with ways to verify fasteners are correctly loaded. Our patent list is growing with specialty products, all centered on solutions to increase the odds of actually achieving and maintaining design load. The vision and goal of Valley Forge building load indicating fasteners, faster, better and cheaper is becoming a reality.
The Clarkester™ Tester for proving torque develops load in mill lining systems, is now a stocked item at Valley Forge with demand and results in the mining community. Information on load rather than torque is being discussed more often and products are readily available from Valley Forge and various other suppliers. ASTM F 2482 has laid the base rules for product classified as Load Indicating Externally Threaded Fasteners. As more sites and application benefit with the use of load for installation over torque, we push for engineered manufacturing to drive cost out and open the market to more than bolts labeled as critical in application. Predictive maintenance with the use of load in the fastener is being tested with instigating cracks in loaded fasteners. There is more to do and tests are underway with Wired and Wireless systems, temperature limits of reading bolts (currently reading at 640 F) and gauges. The future of fasteners is loaded, and we look forward to moving away from being torqued!
