Assessment of airshaft failures in paper reels

✍ Scribed by J Vogwell

• Book ID: 103996581
• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 503 KB
• Volume: 3
• Category: Article
• ISSN: 1350-6307
• DOI: 10.1016/1350-6307(96)00013-1

✦ Synopsis

Abstraet--Airshafls are commonly used in manufacturing processes for fitting to a reel that is used for winding rolls of material such as paper, card and plastic film. An airshaft is designed so that, on fitting into a reel, it can be readily expanded, thereby achieving a firm attachment: it may also be easily contracted prior to dismantling to facilitate removal. Their efficient design makes them ideal for quick and firm attachment onto a reel and then mounting onto bearing housings to enable the winding or unwinding of rolls of stock material with the minimum of equipment down time. The inherent shape and functionality of an airshaft means that failure by fatigue and fracture is a major concern. The airshaft, for example, has a cross-section which changes along its length and it is subjected to significant bending stresses, which alternate with rotation. The weight of the roll of material will also change appreciably during operation and, in addition, the inflated inner tube pressure further increases stress levels at critical locations. This paper analyses the service failure of a specific airshaft, from both fatigue crack initiation and crack propagation considerations, and discusses how the failure might have easily been avoided.