The Value of Inspecting Bolts Visually

Inspecting your bolts is an important job. Secure bolted joints have a direct impact on the reliability, performance and safety of your operations. However, physical bolt inspection can also be a labor-intensive and time-consuming activity. Our customers have reported that visual bolt inspections offer cost-savings and performance benefits compared to traditional maintenance methods which require that workers check each bolt with a torque wrench.

Tightening SmartBolts |
Inspections of SmartBolts are completed quickly with a visual check of the indicator color.

Visual bolt inspections are up to 10X faster. When many bolts need to be inspected, there is considerable value in reducing the time required to inspect each bolt.

In the open-pit mines of Chile, mobile stacking conveyors transport and stack ore for future processing. These conveyors are supported by a series of truss frames spanning hundreds of meters. SmartBolts installed in structural joints of the truss frame provide visual indication that the critical joints are secure so the conveyor can operate reliably and continuously. Without a visual inspection method, costly shutdowns would be required for maintenance personnel to inspect hundreds of bolts with torque wrenches. 

Visual bolt inspections are hands-free. In cases where bolts are difficult to access, visual inspection enables a worker to perform inspection without touching the bolts.

Eaton integrated SmartBolts into its Pow-R-Way III and Pow-R-Flex busway products, which distribute electricity in commercial and industrial facilities such as data centers. Maintenance must be performed on a regular basis to ensure the critical bridge joint bolts remain tight. Previously the entire busway needed to be de-powered so workers could physically check each joint connection with a torque wrench. Now, SmartBolts provide a visual indication that each bridge joint is secure, and the busway can remain operational during the inspection process.

Visual bolt inspections promote safe work practices. Sometimes, bolts are in hazardous places. While security of these bolts is critical to operations, it’s also critical to ensure personnel are not placed in harm’s way.

US Farathane, a leading US plastics manufacturer, relies on visual inspections of SmartBolts to ensure mold bolts are properly tight while ensuring a safe working environment for its employees. At USF plants, massive machines use hundreds of tons of pressure to create plastic parts. The parts are shaped by mold dies bolted to the machine, some weighing as much as 30 tons. These bolts must be checked at each changeover. SmartBolts make it possible for employees to visually inspect that the heavy dies are securely bolted to the platens while avoiding the need for workers to climb into the machines with special tools and wrenches.

Visual bolt inspections are more accurate. Traditional inspection methods often use torque measurement, which is unreliable because of hidden friction factors. SmartBolts bypass this limitation by measuring bolt tension directly.

Concerns about the accuracy of bolt installations led the National Weather Service (NWS) to choose SmartBolts for use in 159 NEXRAD weather radar sites. At each site, radar originates from a rotating antenna dish 28 feet in diameter which operates 24-hours per day. The bolts that secure the antenna pedestal are critical to keeping the radar system properly aligned. NWS engineers concluded that the use of torque wrenches resulted in unpredictable levels of bolt tension, so the NWS switched to SmartBolts to ensure bolt installations were accurate and the radar system would remain reliable. Now, SmartBolts safeguard the most critical bolted joints in the NEXRAD system.

Visual bolt inspections provide increasing value over time.   A regular and comprehensive bolted joint inspection plan can ensure that your equipment remains reliable, high-performing and safe for many years to come.  Unfortunately, traditional inspections using torque wrenches are often too expensive, difficult, or time-consuming to conduct as frequently as necessary. These issues can be solved by using visual tension indicating SmartBolts. Visual bolt inspections provide immediate benefits that reduce both the short and long-term costs associated with maintenance, and improve your operations so they can perform at their optimal level. How much time and money could you save by switching to SmartBolts?