In a bolted joint, tightening the nut actually stretches the bolt a small amount, like pulling on a stiff spring. What Causes Loose Bolts?īolted joints are critical to the safe operation of many types of equipment in a wide range of applications, including power generation, manufacturing, mining, and transportation.

Under constant vibration from the engine of an ocean freighter, loose bolts on a large piece of mining equipment work their way off the bolted joints and roll around the hull, inflicting further damage to the equipment. A rotor with its blades separates from the nacelle and spins off a wind turbine, crashing to the ground. A pressurized bolted flange joint assembly begins to leak, creating a safety hazard.