In-service fatigue cracking of the propeller shafts joined by a spline-pinned construction to the engines of AN-24, AN-26, and IL-18 aircrafts
Journal Title: Frattura ed Integrità Strutturale - Year 2014, Vol 8, Issue 30
Abstract
The paper delivers a critical review of the research data on the crack initiation and crack growth patterns characteristic of the components of the spline-bolted joints between the propeller shaft and reducer shaft at An-24, An-26, and Il-18 aircrafts. Cracks in the shafts nucleated because of reduced bolt-fastening force. Actually, the bolt (bolts) failed first (also by fatigue) and then fatigue cracks nucleated and grew in the shafts, the spline surface fretting zones and/or sharp edges of the attachment (bolt-conducting) holes making the crack origin sites. The crack growth history shows itself through the regular Macro-Beach Marks, each mark sequentially pointing to the next loading event of the propeller shaft, i.e., to each next flight. The cracks cease growing for some while in the airscrews and their shafts just replaced to another aircraft. For the airscrew shafts, the critically assessed data show the crack growth period Np ranging as five to ten percent of a total running period Nf . We recommend performing nondestructive inspection of the airscrew shafts on every 250- hour running period to ensure the safety flights.
Authors and Affiliations
A. Shanyavskiy
Keywords
Related Articles
- EP ID EP94588
- DOI -
- Views 69
- Downloads 0
Time-history simulation of civil architecture earthquake disaster relief- based on the three-dimensional dynamic finite element method
Earthquake action is the main external factor which influences long-term safe operation of civil construction, especially of the high-rise building. Applying time-history method to simulate earthquake response pr...
A new method for the experimental study of fatigue behaviour of thermoplastic materials
Nowadays most industrial realities undergo a strong push to improve cost-effectiveness, productivity and quality of manufactured products. In particular we focussed our attention in the area of design of plastic structur...
Compliant actuation based on dielectric elastomers for a force-feedback device: modeling and experimental evaluation
Thanks to their large power densities, low costs and shock-insensitivity, Dielectric Elastomers (DE) seem to be a promising technology for the implementation of light and compact force-feedback devices such as, for...
Individuazione frattografica di rotture per fatica in componenti metallici con microstrutture complesse
L’individuazione frattografica delle fratture per fatica risulta spesso piuttosto complessa nei materiali che non esibiscono adeguata duttilità. Microstrutture complesse caratterizzate dalla presenza di numerosi co...
Geometric numerical integrators based on the Magnus expansion inbifurcation problems for non-linear elastic solids
We illustrate a procedure based on the Magnus expansion for studying mechanical problems whichlead to non-autonomous systems of linear ODE’s. The effectiveness of the Magnus method is enlighten by theanalysis of a...